Technical Paper 347 

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MISSION/DATA -BASE IMAGERY CORRELATION

TECHNIQUES (M/DICT)

E.SeweII

Raytheon Company/Autometric

A. Harabedian

Human Factors Research, Inc .

and

T. E. Jeffrey U.S. Army Research Institute

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HUMAN FACTORS TECHNICAL AREA

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U. S. Army

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October 1978

App rov.d for pubI~c reI~ .se , d’itr~but’on unI,m t

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U. S. ARMY RES EARCH INSTI T UTE

FOR THE BEHAVIORAL AN D SOCIAL SCI ENC ES

A Field Operating A gency under the Jurisdiction of the

Deputy Chief of Staf f for Personnel

Wit 11AM L. IIAUSER

JOSEPH ZEIDNER (

~~IoneI . US Army

Technical Director ( olnnl4nder

Research accomplished under contract to

the Department of the Army

Raytheon Compan y

Human Factors Research , Inc .

NOTICES

DISTRIBUTI ON Pr.mary d,str,but,on of th~ report hu biIr

~ made by ARt PIe.ie iddress correipondifl.5

co~

,cern ng d’str buipon of reports to U. S Army Rsie.rch Insi tu te for the BSh.vorsI md Soc .I Sc.,ncu.

ATTN PERI P 5001 E s.’r

~~~~ A~enue . AIe,ancj. a , Vgna 22333

FINAL DISPOSITION TNs n oon may be distroysd when t i no longer needed P1.., do not ritu,’ i t o

the U S. A ”v’~ RIIeirch Institut, for the Bih.v or.I md Soc el Science s

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LQ.IL, In. fndn g~ in th~~ report •n, not to be constr ued as an oft c .l D.p.rtm.nt of the Army position . unhist so dssgn e?sd by Ot her .uthOn~~

.d documents

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rrr ~ r*!ft InCA’rIoN OF THIS PAGE (VP ..’ 0... Enr.,.4)

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~J RE RI DOCUMENTATION PAGE READ II4STRUCTIONS

______________________________________________ 

BEFORE COMPLETBIG FORM

3. RECI~~~~~’

~ t. ILt U-k t$ CATAL OO NUM•ER j 2 . GOVT ACCESSION NO 

T ,R4” 

Technical e - —

REPORT C~~~~~~ 1. TITLI (— ‘ J _ L NIIJ OO COVERED

TECHNIQUES ~ r/DIC1~~. 1 May ~~73 ~~~~ 30 Apr 6 074 ~~

JIISSION/pATA—BASE IMAGERY CORRELATIOfr ( — —J Final Rep ’t s

— 

I _________ ...... ORD. .‘~~~~~ ‘,WUNSEft 1 / ______ 

FR74_ 1497 / _ _ _ ~~~~~~~~ — I

~~~~~~UTRAC,~ ON GRANT NUMSIN(.)

~~~~~ ~~~~ ell ,iRaytheon Company/Autometric ; ______

A. ,i1arabed~~~4, Human Factors Research , Inc.; and ~~~~~~~~~~~~~~~~~~~~~ T./~effreyç~~RI ____________________________

P.,,r u ~~~1W~~~~RGAM IZA Tl ON NAM E AND ADDRESS ID PROG ~MLN’.P GJ T TASK

Raytheon Company , Equipment Division V ANEA ~~~~~~~~~UNIT NUM•~~~S

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O6A , I2Q1~2~.Ø6A72lj Boston Post Road

Wayland , Massachusetts 01778 

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II. CONTROLLING OFFICE NAME AND ADDRESS L—~ 5 5flT VAIBi

Department of the Army Oct~~~~ ~~78J

Office of the Assistant Chief of Staff for GES

Intelligence (DAMI) , Washington , DC 20310 56

54. MONITORING AGENCY NAME S AODRESS(If dSff.,w I 1,00, Cw,troIISnd Offic.) IS. SECURITY CLASS. (of lbS. ,.por t)

U.S. Army Research Institute for the Behavioral Unclassified

and Social Sciences (PERI) ______________________________

5001 Eisenhower Avenue 55.. DECLAS SIFICATIO N/OOWNGRADINO / SCHEDULE

Alexandria , VA 223 33 

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IS. DISTRIBUTION STATEMENT (of lbS. R.po~t) /

Approved for public release; distribution unlimited.

Il. DISTRIBUTION STATEMENT (of (ho .b.fr.c( wt.r.d In Block 20. If dlff.r.,t fr o., R.porr)

IS SUPPLEME NTARY NOTES

IC. KEY CORDS (Co .iSi nu. 00 ~~~~~~ .Sd. If n.c...or~ .d Id00(Ifr by block n.,mb.r)

Coordinate determination Target acquisition Analytic transformatioc

Stereoscop ic data—base photographs SLAR imagery program

Imagery correlation IR imagery

Analytical Photogrammetric Target transfer

Positioning System (APPS) Television display

20 ~~~ TI5AC? (C.&Sn.w 00 ,0 0

~~ 00 OI~~ It ~~~~~~~~ ~

d Id.nSI~~ by block .....bw)

‘\The Analytical Photogrammetric Positioning System (APPS) was developed

to determine accurate target location data. APPS operators t ransfer target

locations from mission images to a vertical data—base photograph in determining target coordinates.

The speed and accuracy with which experienced interpreters of side—

looking radar , infrared , and television images transferred annotated locations

(continued)

Unclassified DO CORN COIlION OP NOV IS IS OBSOLETE

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SECURITY CLA SSIPtC*~~~ W or THIS P405 n :1 Dw. tntw.~~

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________ 

Unclassif ied ___________

~~~C L I RITY CLA SSIi ~~~~A T I O 55 OF iHISIAG E ~

TA., 1), U2 £ni.i.d)

20. (continued)

from such sensor images to a vertical data—base photograph were determined .

Annotated locations used were A—Type (those on or near a terrain feature

identifiable on mission and data—base images) and B—Type (those 200 or

more meters distant , on the ground , from such mutually identifiable features). Transfer techniques were of two kinds : (1) direct transfer in

which visual correlation of mission and data—base images was used ; (2) in—

direct transfer where the required point was transferred using a photogram—

metric transformation method employing auxiliary çoints that were mutually

identifiable on mission and data—base images.

Results from nine interpreters are sunmiarized below :

PROPORTION OF TRANSFERS BY ERROR RANGE (METERS)

A—Typ e Locations B—T ype Locations Transfer

Technique 25% 50% 75% 25% 50% 75%

Direct 0—21 0—34 0—52 0—39 0—75 0—130

Indirect Same as above 0—35 0—54 0—64

The improved accuracy of the indirect method for B—Type locations requires

more time . Direct transfer required about 1.3 minutes per target on the

average while indirect transfer per target on the average was five times

that amount or 6.5 minutes per target. -

Uri c lps~ ified SECuRI t Y CLA ~~S iFiCA T ~~OI OF T i c POO l Iii .,, fi,

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Technical Paper 347

MISSION/DATA BASE IMAGERY CORRELATION

TECHNIQUES (M/DICT)

III V~Its lecit., E. Sewell

s,

~ S.CIIW 

~ Raytheon Company/Autometric

A. Harabedian

Human Factors Research , Inc.

and

I, .. ._...__._.__ 

~

!tTsis~

ro1,na’uJlLln cosu T. E. Jeffrey

U.S. Army Research Institute

L

~~~~~ 1 

HUMAN FACTORS TECHNICAL AREA

Submitted as complete and Approved By:

technically accurate , by:

Edgar M. Johnson Frank J. Harris, Acting Director

Technical Area Chief ORGANIZATIONS AN D SYSTEMS

R ESEARCH LABOR ATORY

Joseph Zeidner

TECHNI CAL DIR ECTOR

U.S. ARMY RESEARCH INSTITUTE FOR THE BEHAVIORAL AND SOCIAL SCIENCES

5001 Eisenhower Avenue, Alexandria, Virginia 22333

Office. Deputy Chief of Staff for Personnel

Department of the Army

October 1978

Army Project Number Contract OAHCI9.73.C.0050

20162106A721 Surveillance Systems

Approsed for pubIC rile. .; distribution unlimitsd.

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ARI Research Reports and Technical Papers are intended for sponsors of

R&D tasks and other research and military agencies. Any findings ready for

implementation at the time of publication are presented in the latter part of

the Brief. Upon completion of a major phase of the task , formal recommendations for official action normally are conveyed to appropriate milita ry

agencies by briefing or Disposition Form.

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FOREWORD _________________________________

The Human Factors Technical Area is concerned with the demands of

the future battlefield for increased man—machine complexity to acquire ,

transmi t , process , dissemina te , and utilize information . The research

is focused on the interface problems and interactions within command

and control centers and is concerned wi th such areas as topographic

produc ts and procedures , tac ti cal syrnbology , user—oriented systems ,

information management , staff operations and proced ures , and sensor

systems integration and utilization .

One critical aspect of intelligence information from aerial sensor

is the accurate location of targets. Recentl y, the Army has developed

the Analytical Photogrammetric Positioning System (APPS) which provides

an improved capability for target positioning. However , there are several unknown factors in this system associated with the human interface. The present publication deals with the determination of the

speed and accuracy with which operators can transfer terrain position s

di splayed by side—looking airborne radar , infrared , and television sensor systems to small scale data base vertical phot ographs. A technique

for improving the performance accuracy of the operator of the APPS is

described. The “indirect transfer ” method resulted in a substantial

improvement in location accuracy not only f or conventional photography ,

but also for radar and infrared imagery and , in addition , provides the

operator with a measure of the transfer accuracy.

Research in the area of sensor systems integration and utilization

is conducted as an in—house effort augmented through contracts with organization s selected for their uni que capabilities and facilities for

research on sensor systems. The present study was conducted by personnel f rom Raytheon Company/Autometric and Human Factors Research Inc .

under contrac t DAHC19—73—C—0050 with program direction from Dr. Abraham

H. Birnbaum. The effort is responsive to requirements of Army Project

2Q 162 106A72 1 , the U .S. Army Engineer Topogra ph ic Lab ora tory, Ft. Bel—

vo ir , Va ., and the Assistant Chief of Staff for Intelli gence . Special

requirements are contained in Human Resource Needs 73—65 and 74—19.

‘JO~ EPH ZR.I

~~ ER

~ Thnica1 Director
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MISSION/DATA—BASE IMAGERY CORRELATION TECHNIQUES (M/DICT)

BRIEF

Requirement:

To determine how fast and accurately experienced operators can

transfer target positions from side—looking radar imagery , infrared

imagery , and a static TV display of pho tograp hic imagery to data base

pho tograph y. To develop techniques and proced ures tha t assis t the

Analy tical Photogrammetric Positioning System (APPS) operator to

correlate mission imagery with data base imagery and so enhance the

accuracy with whi ch he can tr ansfer targe ts fro m mission to da ta base

imagery.

P rocedu re:

Three alternative transfer approaches were evaluated early in the

program with the objective of selecting one that would assist the

operator in accurately transferring targets : Optical— mechanical scaling

and restituting equi pment; electr3nic image correlation techniques; and

analytical transformation techniques. An analyt ical transformation

techni que (indirect t ransfer) was determined to be the mos t useful for

transferring targets f rom a variety of reconnaissance imagery.

Mission and data base imagery was selected , and a pilot experiment

was conducted to establish the procedures for the main experiment. In

the main experiment nine subjects directly and indirectly transferred

20 poin ts from three types of side—looking radar and two types of infrared

imagery to data base pho tography. Eigh t subjec ts direc tly transferred

20 points from a static TV display of a vertical pho tograp h to a data

bas e photograph .

Findings :

Ind irect trans fer substantially impr oved th e loca tion accuracy of

targets that were not close to or on a feature identifiable on both

the mission and data base imagery . This improved accuracy was achieved

wi th a cost in time : the average time per target was 6.5 minutes for

the indirect transfer and 1.3 minutes for the direct transfer.

Targe t transfers can be made with useful accuracy to a photo data

base from radar and infrared reconnaissance image ry having a wide range

of scales and ground resolutions . The results of limited experimentation

with a TV disp lay were encouraging: though limited to a relatively high

resolution vertical photograph , transfer accuracy was excellent.
Utilization of Findings :

Opera tional personnel can use the test results in estimating

the accuracy with which targets can be transferred from side—looking

radar and infrared imagery to data b.~se photographs.

The indirec t transfer technique can be used to increase the ver—

sat ility of the APPS for handling a variety of reconnaissance sensor

images. Not only will the accuracy of transfer be improved for targets

in a reas of sparse or conf using image de ta i l , bu t the operator will

be provided with coordina te residuals which are a measure of the transfer accuracy. The availability of these residuals should give the

operator a greater degree of confidence in his work than when using

the direc t transfer technique . For many targets , especially those

appearing on non—p :otographic sensor records , reliable transfers would

not be possible without the indirect technique.

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MISSION/DATA—BASE IMJtGERY CORRELATION TECHNIQUES (M/DIC’r)

CONTENTS __________________________ _______________________________

Page

INTRODUCTION 1

Remote Sensors 1

Background 3

OBJECTIVE 4

METHOD 4

General 4

Developmen t of Experimental Materials 5

Transfer Pro ced ure 7

Point Location Standards 9

Location Error Computation 9

Pilot Experiment 10

Main Experiment 10

Preparat ion of the Data for Statistical Analysis 11

RESULTS 15

Locat ion Errors 15

Point Transfer Times 38

SUMMARY AND DISCUSSION 39

CONCLUSION S 43

RECOMMENDATIONS 43

APPENDIX A. ANALYTICAL PI-IOTOCRAIINETRIC POSITIONING

SYSTEM (APPS) 45

B. INVESTIGATION OF ALTERNATIVE TARGET TRANSFER

TECHNIQUES 49

DISTRIBUTION 55

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LIST OF TABLES

Table 1. Experimental design for the SLAR mission imagery . . . 12

2. Experimental design for the IR mission imagery . . . . 13

3. Number of points on which e

~9h subject ’s error

and t ime scores were based 14

4. Mean location error (me t*rs) for the AN /APS—94

imagery——A points 15

5. Analysis of variance ~~f location errors (meters)

AN/APS—94 imagery——A points 16

6. Mean locat ion error (meters) for the AN/APS—94

imagery——B points ’ 18

7. Analysis of variance of location errors (meters)

AN/APS—94 imagery——B points 18

8. Mean location error (meters) for the AN /APQ— 97

imagery——A points 20

9. Analysis of variance of location errors (meters)

AN/APQ—97 imagery——B points 20

10. Mean location error (meters) for the AN/APQ—97

imagery——B points 22

11. Analysis of variance of location errors (meters)

AN/APQ—97 imagery——B points 22

12. Mean location error (meters) for the AN/APQ— 152

imagery——A points 24

13. Analysis of variance of location errors (meters)

AN /APQ—l52 imagery—-A points 24

14. Mean location error (meters) for the AN/APQ—l5 2

imagery——B points 26

15. Analysis of variance of location errors (meters)

AN/APQ— 152 imagery——B points 26

16. Mean location errors for the AN/APQ—l52 imagery——

points in mountains 28

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17. Analysis of var iance of location errors (meters)

AN /APQ—152 imagery points in mountains 29

18. Mean location error (meters) for the AN/AAS—24

imagery——A points 29

19. Analysis of variance of location errors (meters)

AN /AAS—24 imagery——A points 30

20. Mean location error (meters) for the AN/AAS—24

Image ry——B points 32

21. Analysis of variance of location errors (meters)

AN/AAS—24 imagery——B points 32

22. Mean location error (meters) for the AN/AAS—27

imagery——A points 34

23. Analysis of variance location errors (meters)

AN/AAS—27 imagery——A points 34

24. Mean location error (meters) for the AN/AA S— 27

imagery——B points 36

25. Analysi6 of variance of location errors (meters)

AN /AAS—27 imagery——B points 36

26. Mean t ine (minutes) to transfer points from each

type of mission imagery 39

27. Summary of results foc location errors 41

LIST OF FIGURES

Figure 1. APPS stage p lates over datagrid 7

2 . Cumulative percentage of location error : AN/APS—97

imagery——A points; direct and indirect technique

combined 17

3. Cumulative percentage of location error: AN/APS—94

imagery——B points 19

-. . Cumulative percentage of location error : AN/APQ—97

imagery—-A points; direct and indirect technique

combined 21

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5. Cumulative percentage of location error: AN/APQ—97

imagery——B points 23

6. Cumulative percentage of location error: AN/APQ— 152

Imagery——A points; direct and indirect technique

comb ined 25

7. Cumulative percentage of location error: AN/APQ —1 52

imagery——B points 27

8. Cumulative percentage of location error: AN /AA S—24

imagery——A poi’~ts; direct and indirect technique

combined 31

9. Cumulative percentage of location error: AN/A.AS—24

imagery——B points 33

10. Cumulative percentage of location error: AN /AAS—27

imagery——A points; direct and indirect technique

combined 35

11. Cumulative percentage of location error: AN /AAS—27

imagery——B points; direct and indirect technique

combined 37

12. Cumulative percentage of location error: TV imagery . 38

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MISSION/DATA—BASE IMAGERY CORRELATION TECHNIQUES (M/LiICT)

INTRODUCTION

Remote Sensors

For several decades the aerial camera has been the primary sensor

for collec ting tactical and strategic intelli gence of denied areas.

Aerial films used in these cameras are capable of storing millions of

bits of information in a form readily interpretable by image analys ts.

Even unskilled personnel can read useful information from an aerial

pho tograph beca use the images of ground objects look like the objects

themselves. This seeming ly perfect sensor has two major disadvantages:

it will not pene trate clouds , fog or smoke ; and it requires the object

to be well illumina ted , preferably by the sun . Even though this latter

disadvantage can be overcome somewhat by using pyrotechnic and electronic

flash eq uipment and low—li gh t level amplifiers , photography is essentially a day time reconnaissance tool.

Two other remote sensors are becoming increasingly important to

mili tary reconna issance to suppl emen t aer ial photograph ic reconnaissance. One is side—look ing airborne radar (SLAR) equipment and the

other is infrared (IR) scanner 2quipment. A third reconnaissance tool

that has promise is airborne television ~

..‘hich ; rovides real—time reconnaissance plus the possibility of low—light level operations .

Side Looking Radar — Side looking radars are capable of all—weather ,

day or night operation. They detect the presence and location of

physical objects by transmitting a short pulse of electromagnetic energy

in the direction of the object and sensing the energy as it is reflected

back from the object; the narrower the beamwi dth , the shorter the pulse ,

the smaller the area in which the beam strikes and reflects , the higher

the resolution. Though higher fr equencies usually provide better resolution , they are mor e suscep tible to a tmosp her ic attenuatlons .

Radars are classif ied as either conventional (non—coherent) or

coherent systems . The conventional radars use a physical antenna of

lim ited size . The range resolution of these systems depends upon pulse

wid th and is , essen tially , a cons tant for a particular system. Azimuth

resolution is dependent upon antenna bean width and deteriorates with

range . Coherent systems use a synthetic antenna aperture generated by

the motion of the aircraft. The resolution of such systems may be constant in range and azimuth , and is significantly better than that of

conventional systems . Coheren t systems record a D oppler phase h istory

and require coherent processing to convert the recorded signal data to

a high resolu tion graphic. Both the conventional and coherent systems

may have a moving target indication (MTI) capability .

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When ope r ated in the MTI mode , the radar equipment produces two

records——the fixed target indicator (FTI) record , whi,:h ...s the more

familiar radar record and a subdued FTI record on which the moving targets are imaged. The subduing of the radar background causes the returns from the moving targets to stand out more clearly . Moving objects

can thus be detected and recorded even though the radar would be unable

to detect the same objects if they were stationary .

Infrared — Even though IR imagery looks like photographic imagery there

is more difference than meets the eye , especially in its geometry and

its spectral sensitivity. A short description is given of the special

proper ties of IR that make it unique in providing certain kinds of

intelligence information.

Infrared radiation is electromagnetic energy of wavelengths between the visible and the microwave regions of the spectrum; that is,

0.72 — 1000 microns . All objects whose temperatures are above absolute

zero (Q0 Kelvin or —273 ° Centigrade) emit inf rared radiation . Like

visible light , inf rared radiation travels in straight lines outward

f rom the sou rce; it can be focused by lenses or m irrors; it can be dis—

persed by prisms ; and it is propagated in a vacuum as well as in physical media such as liquid s, gases , or solids. The amoun t and spectral

distribu tion of the radiation emitted by an object depends upon its

temperature and surface characteristics. Much of the radiation emitted

by an object is not available at the detecting equipment due to atmospheric at tenuation . The atmosphere does no t ab sorb un iformly all

infrared waveleng ths. Instead , mos t absorption occurs at definite waveleng ths or “bands ”. Thus , there are areas of the spectrum , called

window reg ions , wh ere the atmosphere is effectively transparent. To

detect in frared r adiation after it has passed through an atmosp heric

pa th , detector s that are sensitive to radiation in these window regions

must be employed .

The surface temperature of oblects depends , among o ther th ings ,

upon their physical str uc ture , compos ition , and ab ility to absorb solar

radiation. Of course , the su rface temperatures of va rious ob jec ts on

the ea rth ’s surface are different. Since the temperature and surface condi tions of objects on the earth ’s surface differ , their infrared characteristics also differ in intensity and spectral distribution.

For reconnaissance pu~ poses , infra red radiation is recorded on

film b y an electro—optical u~ vlce called a scanner , which de tects

radiation over a very small angular field of view . Since most reconnaissance systems require large area coverage , the small field of view

is made to cover a large area by scanning it across the ground . The

scanner ’s de tector outpu t is used to intensity—modulate a glow tube or

a cathode ray tube. The ligh t from the tube is then focused on film

Ia a manner which reproduces the original scan . The dens ity of the

film image is thus proportional to the detector output , or more basically, to the apparent temperature of the area on the ground within

the field of view at any one instant. The result is a thermal map

whi ch shows variations in the surface temperature of the terrain below

the aircraf t.

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Television — Airborne television (TV) can be used for military operations in many ways. One use is in low—light level conditions. Sys—

tems have been built for nighttime use for navigation , reconnaissance

and strike missions in counterinsurgency operations. The output of

th e system can be viewed locally on a CR1, transmitted to a remote TV

receiver or recorded on film by means of a recording camera. Use can

be made of a high resolution return beam vidicon for imaging the scene

of interest. This record also can be viewed locally on a CRT or trans—

mitted to a remote image recorder or display . Further , TV can be used

for transmitting photographic, radar , infrared , or other graphical

records from one station to another.

Photography — Conventional photography is the prime remote sensor reconnaissance tool for-daytime and clear weather operations . Since optimum

ground resolution is provided by photography it Is an obvious choice

for data bases. A data base must have high ground resolution and high

geometric fidelIty so photography from precision cartographic cameras

is preferred . Usually , data bases are made from six—inch focal length,

9” x 9” format photographs that have been related to each other and to

ground control through aerotriangulation.

Background

Autome tric completed for ARI a study to determine how fast and

accurately points could be transferred from various types of reconnaissance photographs to a photo data base . In that study it ~

‘as

learned tha t grou nd resolution and background density are two major

factors in transfer accuracy .

It was found that , w ith one excep tion , ground resolution of the

mission image ry did not appear to be a significant factor. The reason

seemed obvious . Because most reconnaissance photographs (mission

image ry) have scales considerably larger tha n the 1:100 ,000 data base

scale cur rently being recommended for the APPS , their ground resolutions are be tter than that of the data base. In the transfer process

the limiting factor apparently was the ground resolution of the data

bas e , not the ground resolution of the mission imagery. The one excep tion , where ground resolu tion was a significant fac tor , was the Far

posltion of the Low Pan mission imagery. The ground resolution for

that photography was so poor that even a small degradation caused a

significan t loss of the detail useful for accurate point transfer.

Someth ing akin to ground resolution becomes a signif icant factor

when work ing with non—photographic sensor records. Since SLA R and IR

sensors record informa tion that is different from that recorded by the

pho tographic camera (radar reflectance , temperature of objects) there

a re many images on the non—photographic mission imagery that do not

h~ ve corresponding Images on the photographic data base. For example ,

a building Imaged by a camera would not . ,iow on an IR record if its

temperatu re was the same as the temperat ire of the surrounding terrain.

Or , a relatively small object, having .‘ u g h radar reflectance , might

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be imaged on the SLAR record but not on a photographic film. These 

record differences often make it impossible to make d i rect visua l transfers to acceptable accuracies. 1t is obvious that SLAR, IR and TV of fer 

new dimensions for reconnaissance beyond those provided by photography. 

However, new transfer techniques are needed for targ~ts in a reas o f 

sparse background density and for t argets appearing on these non-photographic sensor records. 

One immediate need for nel-l tar~e t trnnsfer t echni.ques is for use 

with the Analytical PhotoglCHnmetr.ic Positi oning System (APPS)J] recently 

developed at the U. S. Army Enginl!er Topographic Laboratories, Ft. Uelvoir , 

Virginia. The APPS cons ists eo;::;P.nti;tlly of a mirrot· s t e r cosr.opc mounted 

over a coordinate 111 easuring syst em 1-lhosc outputs arc fed t o an i nterface 

unit and then to a programm.::th l e desk calculator. Tl-lv over l.1pf).i. ng dnta 

base photographs are mounted on the two s t ages of the mirror stcr.l.!oscope. 

After an indexing and checking r ou tine, index marks are ploced over a 

point of interest and the attached calculator computes the X, Y, and Z 

ground coordinates of that point. In the previ ous s tudy for ARI it 

uas determined that one major source of e r ror in target location i s the 

transferr i ng of a target image from a reconnaiss<tnce record t o the APPS 

data base. 

OBJECTIVE 

The prima ry objective of this !;tudy 1·/;'ls to d~t mine the accuracy 

and s peed with \111 Lch tr.::tincd i n!ap,e interpreters can tr:1 ns f•.>r tnrge t 

po:; iLion:.; 0 .1 SL U , I:~ , ;Jild ~ L.:! t i.e TV r.1 i ;,s i.on i :~: ,j~ y to p!l .:> 0g r. ~• t i c 

dnta base image ry. 

The St:!Condary objective Has to devel op tr:chn iqucs and procl:durcs 

th.l t assist the Op·:> L':1tor t o corrc.l<tte tni:; .;i.on inwr;t> ry lvlth d<tt.1 base 

imagery .:md so ni, lC P t:he :~; ltracy "'ith 1-.:h ich he c:1n transfe r t a r ge ts 

from mis.,ion t c d~ L.t bar.e i:11c1Ge ry. 

HETHOD 

General 

From the st:udy of alternative tr<lnG[e r tcchni.quGsU camF! the conclusion that the auoly ticnl t ransforma tion ~chni e s hould be used in 

tJ Dcscri~cd more fully in Appendix A. 

See Appendix B. 

-4-
the main experiment. Expe rien ced subjects t r ansfe rred poi nts from

IR and SLAR mission imagery to a photo data base using both the indirect

(analytIcal t ransformatIon) and direct (image association) technique .

Points were transferred from the TV imagery using the direct technique

only . The APPS equipment was used for the pilot and main experiment.

Development of Experimental Materials

A considerab le amount of care was taken In selecting the

imagery for this s tudy. Since only a limi ted number of different kinds

of tests could be m ade i t was im por tan t tha t each m iss ion image con tain

a variety of terrain and cultural features , be of good operational

quality , and be representative of operational scales. In addition ,

ground are as cove red by the m ission image mus t be cover ed by hi gh quali ty fra me pho tograp hy at a scale of about 1:100,000. All the sensors

selec ted , excep t the AAS-~27 Infrared se t , have previous ly been used

operationally or have been tested by the A rmy . The types of mission

image ry selec ted and the geograp hic loca tion covered by each image are

descr ibed below .

1. AN/APS—94 Side—Lo oki_ adar , 1:250 ,000 Scale , Phoenix ,

Arizona — both Nfl and FTI .

The Ai’S—94 , a conventional (non—coherent) side looking radar ,

Is the primary reconnaissance radar sensor used by tire Army . The

MTI mode of operation is used almost exclusive ly by thc A rmy for

detecr~t r r ~ .5 j~~ e5~ - J;ce of targ~ ts. T;rr~ cts r~~ 1n~- . i r’

~ ‘

~y rn rr e—

tation bote cen the radar record and a map . Usuall y, onl y

severel y lH ited position al accuracy is attained.

2. \N/AP (

~

--~~7 SIdc- L oadng Rad ar , 1:160 ,000 Scale , Phoenix ,

Ar izona — Fit only.

The A1’Q—97 is a conventional (non—coh ere~it) side loo~

dng

radar , with lute r t e r u r e tric capabi liLy , de ve l oped by tire Army

for topograp hic napping app lications . It Is fairly rc~~r csen ta—

tive of the state—of—t he—art of non—c e h a rent. radars. lau lated

targets such as vehicles , factories , bridges , etc. can often

be detc c te d even tlrou ~ h they cannot be idanti lied.

3. A N /APq --1 52 C O 1Ir•II ~It S[d e—Lookin ~ Rad ar (1OPO_ LI), 1:100 ,000

Scale , l ’hoerix , A r i zona — i-TI only.

The APQ— 152 is a n;a~p ing r

~~J~;r , wit h an interfer ome tric

(terrain elevation determination) capability , being i n v eat i —

g-ited b y tire Am y. It:; basic resa lution is much urr :

~erior to

that of the APS—94 radar. A l a r~ e variety of terrain arid

cultural features can be seen on the imrrge rv . r e ; - latcd targets

such as aut omobil es , i rni- -a , artillery p ieces , etc. can often be

de tected c -an though they cannot be identifi ed.

—5—

L -~~~~~~~~~~ 1

~~

_ _ . _ __ _ __ ________
4. AN/AAS-24 lnfr_ared Sensor, Large Scale (1:8,000), Nighttime 

Operation, Addison Field, Dallas, Texas 

The AAS-24, developed for the Anny represents the state--of-the 

art for operational airborne inf rared cquip~ent. The normal 

operating altitude for this s e nsor is 500 fe et to 3000 fee t. 

The i oagery select d for thes e tests was recorded at 2700 feet, 

resulting in a scale alonJ; the flight p.:1 th o f about 1 : 8,000. 

A nighttime record h'.:tS used since the principal operational 

use of IR sensor::; for re connaissance i s at night. 

5. AN/AAS-27 In~r_!l_E d Scn _or, Small Scale (1:60,000), Nighttime 

Operation, Alcxru;.dria, Virginia 

The t\AS-27 is an expl.!rirne n tal IR 1~ or developed for the 

Air Force. The imag~ry used for these tests has a scnle along 

the flight path of about 1:60,000. A n ighttime re cord was used. 

6. TV Dis~lay, 1:5,000 Scale, Ft. Heh•oir, Virginia 

A closed-circuit, 525 line s can t e l evision ca~ ra and 

receivc> r producl.!d the missiot\ i.r:tage ry fr.o!:J a 1:20,000 scale 

ncar-vertical photo raph mo•Jnt c J over a light table. 

Except for the TV im:tgery, all of the mi ssion in t~;cs H.:> r c printed 

on ~~ los y photog rap:1ic ap~ r. The i t:1<1ge rJ dis played on ti1e 'LV '-':tS 

pl·intcd on trcms parc nt ph otog r <.![>hi c n a t C' cia l. Th e data b:l';.::s ~re at 

,1 H: .:ll~ c f l:lCC, OCJ .1nJ ·.:ere i.u~ J O Ll d i;uu.: ll~~ti lil•.l i, .• o..;r. c. ti r ~-1l. 

1\-1enty targe t points we re 10:11·!<ed randoml y on each of t he SLAR 

<>nd IR mi ssion i mages. \! i.t·l) the <:: ;-(Cc i. n of the fV n; gc , no ~.; ffort 

\v<l5 macle to choos e Ty pe ,-) J untl n!t../ vo l n t::>. a:> e~ d been dc:;te i n e 

hotogt·ap iti~ '> tudy. ll•)h".'V:.' r, !H~ po i tl t s .Jt ~ cJ'~ ->., if d ..~~ A o r ll 

points after t h ey w~re m.trked. An t-x t ra s t e t> H .:lo..; re'Juircd to nw 1:k all 

::; e lec t ed pointP on the APS-94 as~ ry. The pointG f irs t ~e re mar ked on the 

NTl r ecord, ·.·lhose i:r ~· ~c de tnil Has subdue-d dur.ing the i.l c l')u i.n itiott 

phas e so the moving ~t: ts 1 ima ges ,;ould s t~·1d out o n the r ecord. 

",' ...., Type A points - Point n loc ated on a fe a ture idP.ntifia0le on both 

the mi ,;ion and data base photography. 

~/ Type B points - Points '"htch arc more thnn 200 me ters dis tance on 

the grot:nd Erom a point i.dentifiable on both 

Til ' ssion and data base photo raphs. 

-6-
The background detail was so sparse that it was not possible to transfer

points directly from the MTI record to the photo data base. Instead ,

the puints were transferred to the FTI record by superposing the MTI

with the FTI and marking the points on the FTI record with a sharp needle.

Transparent prints were used for this , and each point was transferred

after matching the detail immediately surrounding it. A precision corn—

parator was used to measure the coordinates of four reference marks and

the 20 points on the MTI record . Coordinates of the same reference marks

(Images identifiable on both the MTI and FTI records) and the 20 points

were measured on the FTI record. Transformation parameters between the

MTI and FTI records determined for the reference marks , w er e app lied to the

coordinates of the poin ts on the FTI record. This provided the coordina tes

of all points for the FTI record in the MTI coordinate system. The transfer error was found by taking the absolute difference in X- and V—coordi -

nates for each point. The mean transfer error for 28 points was 20 meters

on the ground.

Transfer Procedure

Previous point transfer tests showed that , generall y, the direct

technique of transferring is inadequate for points in areas of sparse

background detail. In one phase of this study alternative point transfer

methods were investigated. In that phase , it was concluded that a

6—parameter analytical transformation technique was the most suitable

and that to be of practical value , all coordinate measurements for the

transformation should be made on the APPS.

The following is a brief description of the API’S measuring components and of t h e. transfer procedures used in this expe ri-.nent.

The APPS 1105 two stage plates tor holding a pair of photographs .

Figure 1 is a schematic diagram of the stage plates over tine datagrid.

Index Marks~ -— ~~ I ______

+_ lit + -+

Left rete re n c~ ~ Rtgh t reference

dot dot

I;

i) a ta- k

__________ 

grid~ ___________

Y + + 4- ~- 4 _________________ Sensor - - X—Far a llax

Micrometer

DATAGRID

Figu re 1. APPS Stage Plates Over Datagr~ d

—7—

- -

~~--~~ -- - -
The stage plates are mounted on a carrier and can be moved

together in X and Y . One plate can be moved relative to the other

by X and Y micrometer screws . Under the plate carrier is a data—

grid that senses and records movements of the carrier. Mounted

directly over the two stage plates are two glass dIscs with a reference dot in the center of each . These discs are stationary ; that

Is , the plates can move under them . The dots are on the bottom of

the discs and abo ut ~ mm above the surface of the data base photographs .

Each data base photograph has six index marks (only fo ur are

used for each stereo model) to which all auxiliary data such as

posi ti a -n , attitude , and camera constants are referenced . Additionall y each data base phot o h-nag at least one check point whose X , Y,

and Z. coordinates were determined during the aerotriangulatlon phase.

For the normal APPS operation , a stereo—pair of pho tos is moun ted

on the two stage plates. After initial measuring of the index marks

and the check po in t , coord ina tes of any po in t in the overlap area

can be found b placing the reference dots on the Images of the

point 01 interest and activating the foot switch .

For these tests one data base photograph was mounted on the

righ t hand stage plate and fastened securely. All Index marks were

measured and recorded. The mission imagery was rlaced on the left

hand stage plate and moved so the particular point to be transferred

wa s benea th the left hand reference dot and the appr oxim ate loca tion

of tb-n t m int r

~n ~he datni base nj -na hc;ie-arh the riot hand dot. To

make a direct t r anister tine operator first viewed the mission imagery

through the left eyepiece and then tine data base through the right

eyep iece . Alter alternately viewing the mission i;aigery with one

even and the data base with the other , tine subject selected the

place on the data base that lie judged to correarotid to the point of

interest on the mission ima gery . The r ight hand dot was positioned

over that place and the X , Y coord inates were recorded on paper tape

by pressing the foot switch .

To make an Ind irect transfer (anal ytIcal transformation) the

subje ct searc ied for six points surrounding the t ar~ et point whose

images could he Identified on both the mission and d .tta base

imagery . The subjects were instructid to select points as close as

V p os-;ible to the targe t point. Corresponding points were tound by

alternatel y viewing the mission imagery through the left eyepiece

and the data base photo through the r igh t eyepiece . The Images

were not ph ys ically marked on either record . When a “control ”

point, was found the subject measured the coordinates of that, point ’s

image , first on the mission imagery by placing the left dot on the

image and activating the foot switch and then on the data base by

placing the righ t dot on the image and activating the foot switch .

This was repeated for each control point. An I d e n t i f i c a t ion number

was entered into the APPS ’ programmable desk calculator before each

control point was measured.

— 8—
The desk calculator, which contained a 6—parameter transformation program , was activated and the transformation made .

The x— and y— residuals for each control point were printed on

paper tape after the transformation was comp leted . The left

dot was then positioned over the tarczet point , the computer was

activated , and th e x and y coordinates of the target point , in

the data base coord inate system , were printed on paper tape .

Usually, it the values of the residuals were greater than 0.010

inches , new control points were selected and the transfer

proces s was repeated.

Point Location Standards

Point Location Standards (school solutions) were established for all points on each frame of mission imagery . Since

the tests were to be conducted with the APPS equipment it was

advan tageous to develop the location standards in the coordinate

system of the APPS so direct comparisons could be made. LocatIon

studs were fastened to the right stage plate so each subject

could reposition the data base accurately . The school solutions

wer e developed by mak ing repeated local analytical transformations for each point and by direct transfors , when possible .

Special care was taken in mountainous areas of the. TOPO II

atiraulus imagery. For points in the-ac arcas b o t ~h the radar and

data base were viewed in stereo so points could be transferred

with greater certainty.

Location Error Computation

Each subject transferred all points annotated on the

SLAR and IR images to the appropriate data base images by

Direct Technique and the Indirect Technique separately. Only

the Direct Technique was used for the TV ima ’ery . The location

error in two dimensions (x and y) was det :ermined for each point

for every subject by tak in g the ab solu te d i fference b etween the

school solution and the observed solution .

—9—

I

- - - ~~~~~ -~~~~~~~ “~~~~~~~~~- 

~~~~~~~~ - - -
___ ___________ --

Pilot Expe rimen t

A pilot experiment was conducted to determine the suitability of

the procedures planned for the main tests . The 6—parameter transforma ti on program , written for the APPS p rogramm able calcula tor , was tested

for adequacy and speed , using pho to , SLAR and IR mission imagery . Time

trIals were run to provi de data useful in plann ing the main tests . The

subjects felt their efficiency dropped off app reciably after 3 to 4

hours continuous operation . No objective quantitative data were collected to verify this. The pilot experiment showed that the Indirect

Techn ique proposed for use with the APPS equipment is useful for transferring po in t s in areas of sparse back ground density , so no cha nges

were deemed necessary for the main experiment.

Main Experimen t

Subj~~cts and Subject Traini.~~~ Eleven (11) subjects , provided by

the contractor , participated in the experiment. Even though all subjects were familiar with several types of mensuraLlon equipment , none

had previous experience with the APPS equipment. Some of the subjects

were experienced image interprete rs , oth ers had lim ited interp retation

experience bu t we re exper ienc ed photograc~

metrists.

Since only one APPS was available , the subjects were tested one

at a time . Each subject was instructed on tine use of the APPS . The

instruction was sufficiently detailed to permi t him to turn on the

eq nn inr - -~nt , 1 oad the c cn m :) mtn r ‘

~roor :~-”-~ ~~- - ro the ~- 1 i ~~--n nt ;rnd ~.ako

appropriate data—base checks , and produce the measurement~; in the

prope r formats.

E x 1e irc-nt a 1 Desi~~n. Ihe nine subjects transferred all of the

po ints from each tYpe of IR and SLAR imagery to the data base using

two t ransfer techniques——Direct and Indirect . They completed the two

IR images first , the thr ee StAR images next , and the one TV image last .

Six of the nine subjects and two additional subjects (eigh t subjects )

transferred the points from the TV imagery .

The order of the two IR images , ti-n e three SLAR images , and the

two trinsfer techni ques i:as counterbalanced to the degree possible

across groups of subjects. This was done to contr - l for tine possible

effects of time— related variables such as boredom , fatigue , and

learning. Because there we re nine subjects , complete counterbalancing

was pos sible onl y for the order of ti-n e SLAR imagery . The order of the

IR images and the transfer techniques was partially counterbalan- ed.

-10—

,6

---

~

- -

-~
, 

Table lA shows the order in which the three SLAR images were 

presented to each group of subjects. An equal number of subjects (3) 

were presented with each SLAR image, first, second, and third. 

Table lB shows the transfer technique used first by Mission 

Image and Groups. One subject from Group 1, two from Group 2, and 

one from Group 3 used the Direct Technique first with the APS-94 and 

APQ-152 imagery and the Indirect Technique first with the APQ-97 

imagery. Two subjects from Group 1, one from Group 2, and two from 

Group 3 or a total of five subjects (Group B) used the Direct Technique first with the APQ-97 imagery and the Indirect Technique first 

with the APS-94 and APQ-152 imagery. 

Table 2A shows the order in which the two IR mission images were 

presented to each of the groups. The five subjects in Group 1 were 

given the AAS-24 imagery first and the AAS-27 imagery second; the 

four subjects in Group 2 were given the imagery in reverse order. 

Table 2B shows the transfer technique used first by t-fission 

Image and Groups. Three subjects from Group 1 and tt.;o from Group 2 

or a total of five subjects (Group A) used the Direct Technique first 

with the AAS-24 imagery and the Indirect Technique first \oli.th the AAS-27 

imagery. 1\.ro subjects from Group 1 and two from Group 2 or a total of 

four subjects (Group B) used the Direct Technique first with the AAS-27 

imagery and the Indirect Technique first tV"ith the AAS-24 imagery. 

\'~rloble . '!' h~ e Has 0ne :v'(>':' '1 il t:>:H v;; r ; .'"ll,l,.., tT.;m!':fP.r ter.hnique, for e a ch IR and SLAR image. There tV"as no independent variable 

for the TV image since the purpose of the experiment tV"as merely to 

estimate the location error. 

There were tt11o ndent vari ab_les for each type of imagery: the 

location error (in inches ), which was then scaled into meters on the 

ground; and the time (in seconds) required to transfer a point. 

There were two con~rol v3riables. One was the type of point, 

A and B. These points t11cre labeled in terms of significant background 

detail, i.e., point/environs. The other \V"as the order of the IR images, 

the SLAR images, and the transfer techniques. 

Preparation of the Data for Statistical Analysis 

The measure of each subject's location error and transfer time 

performance for each mission image was the median error and time for 

the A points and for the B points. The median rather than the mean 

-11-
Table 1 

EXPERIMENTAL DESIGN FOR THE 

SLAR MISSION IMAGERY 

A. Order of the Mission Imagery by Groups 

MISSION ORDER 

HIAGERY 1st 2nd 3rd 

AN/APS-94 Gp1a Gp, Gp2 

AN/APQ-97 Gp2 Gp1 Gps ·-

AN/APQ-152 GJ:J Gp2 Gp1 

a3 subjects per group {Gp) 

B. First Transfer TQchnique By Mission Image and Groups 

-

TRMI SFE R TECHNIQUE SSION IJSEO FIRST 

/\GERY =4r=--o iBE CT -·J:_t ~_o ~! CT -

/APS-94 Gp A a

/ APQ-97 Gp B 

AN /APQ-152 Gp A 

d4 subjects in Gp A 

b5 subjects in Gp B 

-12-

Gp Bb 

-

Gp A 

Gp B 

' 
Table 2 

EXPERIMENTAL DESIGN FOR THE 

IR MISSION IMAGERY 

A. Order of the Mission Imayery by Groups 

MISSION 

t:~AGERY 

AN/AAS-24 

AN/AAS-27 

as subjects in Gpt 

b4 subjects in Gp2 

ORDER 

lst 2nd 

Gp 1a Gp2b 

Gp2 Gpt 

B. Fit·st Transfer Te chnique lly t•lission Image 

and Gt·ou p s 

--- ·--- -

MISSI ON TRANS FER TEC imiQUE 

IMAGERY USED F !R ST --·-

DIRECT INDIRECT 

A 

- - -----= - ·----· ·--:= 

N/AAS 24 . I Gp A aGp Bb 

N/AAS-27 Gp B Gp A .,.......-. '":-

A 

as subj ects in Gp A 

b4 subjects in GP B 

-13-
was used because the distribution of scores across points was positive ly

skewed for many of the subjects.

Each subject ’s nea , error and time scores were based on the number

of A and B points shown itt Tab le 3. In addition , four points in tine

APQ—l52 imagery were located In mountains. These points we’-

~ “ D t classified as either A or B points . They were un ique in the sense that , bec ause

of relief aisplacement , the Indirect Technique could not be used effectively unless control points could be found at approximately tine same elevation

as the target point. Except for the TV imagery , each subject had a Direct

and an Indirect Technique error and time score for e-nei point type.

Table 3

NUMBER OF POINTS ON WHICH EAC H

SUBJECT ’S ERROR AND TIME

SCORES WERE BASED

MISSION POINT TYPE

I M A GERY --_______ ____________

At-~

/AAS - 2 4 I 

8 12

A M /AAS-27 10 10

A M /A PS - 94 9 1 1 ___________ - —- — ,n — -—- ___________ —

~ A M /A PQ-9 7 4 - -

~~~~ 16

A N /APQ- 152 11 5

TV 

— 

7 13

Means of the subjects ’ median errors were used In testing the

statistical significance of the effects of Transfer Techniq ue (indepcnd-.

ent variable) and the Order (control variable). A statistical test

(analysis of variance) was used to test the statistical significance

of these variables and to determine n -;hether or not tine levels of the

variables sh ould be combined for descri p tive purposes.

— 14—
-

~~~~~~~~~

RESULTS

Location Errors

The loca tion errors for each of the mission images are described

in tine following six sections. Wi thin ea ch secti on , the results for

the A p oin ts are presen ted f irs t , and those for the B points , second.

For each point type , there is a tab le of the location error means for

the variables of Transf er Technique and of Order , a statistical test

(analys i s of var iance) of the effec ts of these v ar iables , an d a

descr ip tion of the loc ation error in tine form of cumulative percentage

distributions. Descri ptive statistics based on the cumulative percentage of error we re conside red more appropriate than those based on the

normal d istribution assumption because the distributions of location

error ‘~ere skewed.

A cumulative percentage distribution of location error was computed separately for tine Direct and the Indirect Techni que if the

effect of Techni que was s t a t i s ti c a l l y significant (p < .O5); if not , the

t’ao t echniq iic s were combined into a compos ite cumulative percentage

distribution.

AN/APS—94 Im~~ o~~~. Table 4 show s the error means ~or the AN/APS—

94 , A points. This table and those that follow show the mean error for

the two tccinni ques by the orde r in which they we re used. Re cal 1 that

O’~ ° ~~rm7 of ~~ b j o ct s uc .

~

d t.e D~ nccL foch ,i que ~hisL and Lije Iii di rect

;emirnique second , ~rnd the other group used tine tcc lnni qiies in reverse

order. In this tab le and thos e that follow , the mean ; in one set of

diagonal cells are from one g roup and the other set from tine oth ~ r

group of subjects. For ~ - :aminle , ti ne me ans of 42.6 and 37.6 meters are

from one group and 30.2 and 14.0 meters are from tine other group.

Table 4

MEAN LOCATION ERROR (METERS)

FOR THE AN/APS-94 IMAGERY--A POINTS

TRANSFER ORDER MEAN

TECHNI QUE 1st 2nd TOTAL

DIRECT 42.6 34 .0 38.3

IN DIRECT 30.2 — 

37.6 33.9 —

TOTAL 36.4 135 .8 II 36.1 

—

—15—

______ 

~~—-.--- 

. 

-~~~---- ~~~~~~ --- ~~~~ ~~~~ - -~~~~~~~~ - --
Inspection of Table 4 shows that the Indirect mean total was

slightl y less than the Dir~ ct mean total and that there was essentially

no difference be tween tine Order mean totals .

An analysis of variance of the data (Table 5) indicated that the

effe ct s of Te chni ques and Order were not statistically significant.

The dat a from the two techniques were comb ined .

Table 5

ANALYSIS OF VARIANCE OF LOCAT ION ERRORS (METERS)

AN /APS— 94 IMAGERY——A POINTS

SOURCE df MS F

B e t we en

Subjects

Groups 1 282.7 <1.00

Sub j .w .Groups 7 296.3

W i t hi n

~~bject s. 9

Method 1 85.1 <1.00

Order 1 1.7 ‘-1.00

Error (within) 7 122.1

FI gure 2 shows the cumulative percentage of location error (in

meters) for tine A points. Tine 1

~igure may be interpreted as follows :

if tine interest is in the typ ical or average error on these points ,

select 50% (the median) on th o ordinate and read the value of tine

abscissa (location error) that corresponds to the point where 50% Inter—

sect- the function.

In Figure 2 the 50% value is 34 meters . This means that half

of tho errors were less than and half greater than 34 meters . It tine

int ~~r eot is no t in th e ave rage perf ormance , bu t rathe r in some point

better than avo r - n ~ e , select , for examp le , 757. on the ordinate and

determine tine corresponding value on the abscissa. In Figure 2,

t i at value ~~ 52 me ters. In other words , 757. of the errors were less

than and z1~ wo re greater than 52 meters . Interpretations may be made

In tine same way for other percentages.

—16—

L. - 

. - - - — ---I— - . 

— 

- -
__ -

100 _______________________________________________________________________________

90

80

70

60 . 

-

50 -

4Q

30

20 -

10

0 I I I I

0 10 20 30 40 50 60 70 80 90

L OCAUOU ERROR (MET ERS)

Figure 2 . C um ulative percentage of location error:

A N/APS—94 imagery--A points; Direct and Indirect

Technique combined.

Table 6 shows the error means for the A N /-\PS—94 ima ~ erv , B points.

The me an error was large r on the 2nd trial (75.5 meters ) than on tine

1st trial (56.7 meters), but an ana 1~- -ois of variance (Table 7) showed

th at the difference bet~

.s-en these m e ans was not a t a t i st i cal lv significa nt .

The mean e ~ror was lam e r for the Di r~ ct Teclnniqee (79,6 meters) than

for ~be i ndir o :t T€ chni que (52.6 m eters) and the differe nce between means

was statistically si p i nitican t (p~~.OS). The data fren t~~c two techniques

we re not combined.

— 17— 

~~

-

~~~~~~~~~~ —-——~~ - - -
____________ _ -~~~ __

Table 6

MEAN LOCATI O N ERROR (METERS)

FOR .IE AN/APS -94 IMAGERY--B POINTS

~~ TRANSFER ORDER Jf MEAN

TECHNI QUE J~~~~~~~II~~ TOTAL

DIRECT ______ 

83.8_1

79.6

INDIRECT 43.0 62.2 L52 .6

MEAN

TOTAL 56.7 

— 

75.5 66.1

Table 7

ANALYSIS OF VAR IANCE OF LOCP~T~ ON ER R ORS (MET ER S )

AN/APS - 94 I M AGERY ——fl POINTS

SOURCE df MS F

~ 

c

~ 

t tie en

• ~u i~j t

~Ts 8

Groups 1 0.8 <1.00

Su bj. w .Group s 7 540.0

i!tthin

9

?iethod 1 3234.0 7.70*

Order 1 1 566.7 3.73

Error (within) 7 420.1

—18—

~

--- - — - -~~ - -

~~~
---- - — -- -- -

~~~~~~~- - ---

Figure 3 shows the cumulative percentage of location error for

the AN/APS—94 imagery , B points. The median error for the Direct

Technique was 75 meters and for Indirect Technique , 54 meters .

100

90

0 

I

80

~ 70

.

~~ Iz

‘-I

50

~ 40 -I

0. ~~O I N D IR ( C T

~~ 30

U IDIRE CT

20 

10

0 I I I I

0 30 60 90 120 150 180 210

LOCATIO N (RROR (METI RS)

Figure 3. Cumulative-percentage of loca ti on error:

AN/A PS-94 imagery--B points .

AN/APQ-97 Imagery . Table 8 shows the error means for the AIY~/APQ—97 ,

A points. It is apparent from inspection that the larger mean total for

the 1st compared with the 2nd trial and for the Indirect compared with

the Direct Technique is due solely to the large mean error of 112.5 for

the Indirect—ls t condition . The analyses of variance (Table 9) showed

that the effects of Technique and Group were indeed statistically significant (P < .05), and the effec t of Order approached statistical significance (F 5.53, P < .10).

Even though the Technique effect was significant , the da ta fr om the

two techniques were combined for several reasons : There was a neg]igible

difference be tween Techniques means for Group A (27.4 and 28.8 meters).

Al though the difference between means for Group B was large (112.5 and

34.0 me ters), inspection of the subjects ’ scores revealed that two of the

subjects made very large errors on two of the four points , res ulting in

a large median error for each of these two subjects. Consequently , the

mean error for the Direct—lst condition was considerab ly larger than that

for the Indirec t-’-2nd condition . In addition , the med ian errors of the

cumulative percentage distributions for the Direct and the Indirect Tech—

— niques differed very little (about 3 meters).

—19—
Table 8

MEAN LOCATION ERROR (M ETERS )

FOR THE AN /APQ - 97 IMAGERY--A POINTS

TRANSFER ORDER MEAN

TECHNIQ U E 1s t 2nd TOTAL

DIRECT 27.4 34.0 30.7

INDIRECT 112.5 28.8 70.6

MEAN ii

TOTAL 70.0 31.4 II 50.7

Table 9

A N ALY SIS OF VARIA NC E OF LOCATIO N ERROR S (METERS )

A N/APQ-97 IMAGERY—-A POINTS

SOURCE df MS F

Bet we en

Sub j ects 8

G roups 1 8159.5 7.13*

Subj .w .Gro ups 7 1144.4

W I t h i n

Su bjects 9

Method 1 6372.9 5.92*

Order 1 5955.2 5.53

Error (within) 7 1077.2

* p< .05

-20—

L - ________ -

-—-——~~~~~~. -

~~~~~~~ - - - -•- --- --
Figure 4 shows the cumulative percentage of location error for

the AN/APQ— 97 Imagery , A poin ts. The median error was 29 meters .

1CC

90

80

,. 70 -

I,

‘.~ 60

50

I-.

~ 40 -I

20

I I I I I I I I

0 10 20 30 40 SO 60 70 80 90 100

LOCATI ON ERROR (METERS)

Figure 4 Cumulative percentage of location error:

AN/APQ -97 imagery—-A points; Direct and Indirect

• Tec hnique combined.

Table 10 shows the error means for the AN/APQ—97 imagery , B

points. The larger mean total for the Direct compared with the

Indirec t Technique and for the 2nd compared with the 1st trial was due ,

in part , to the large mean for the Direct—2nd condition . But , no te

also that both 1st and 2nd trial Direct means were larger than the

correspond ing Indirec t means .

—21—

L -

~~~ -~~~ •-—-~~~~~~ ~~

——--
Table 10 

MEAN LOCATIO N ERROR (MET ERS) FOR THE AN/APQ-97 IMAGERY--B POINTS 

TRANSFER ORDER I MEAN 

TECHNIQUE 1st 2nd ! TOTAL 

DIRECT 46.0 84.7 65.4 

INDIRECT 31 . 0 26.2 28.6 

f~"EAN 38.5 55.4 47.0 TOTAL 

An analysis of variance (Table 11) shO\.Jed that the Technique and 

Group effects \o/ere statistically significant (p<.Ol) and the Order effect 

approached statistical significance (F=4 . 74, p<. 10) . ·nte significance 

of t hese mean effects were due, at leas t partly , to the large mean for 

Table 11 

ANALYSIS OF VARIANCE OF LOCATION ERRORS (METERS) AN/APQ-97 IMAGERY--a POINTS 

SOURCE df MS F 

Between 

Subj ect s 8 

Groups 1 1892.2 18. 64 ** 

S u b j . \'1 • G r o u p s 7 1 01 . 5 

Within 

Subjects 9 

Method 1 5402.2 22. 38 ** 

Order 1 1145. 2 4.74 

Error (within) 7 241.3 

** p<. 01 

-22-
the Direct-2nd condition. But, because th e Direct means tve r e lar ger on 

both t r ials than the corresponding I ndirect means and be cause o f the 

significant Technique effel..t, the data from the two techniques were not 

combined. 

Figure 5 shows the cumulative percentage of location error for 

the AN/APQ-97 , B poi nts. The media n error was 56 meters for the Direct 

Technique and 27 mete rs for t h e Indirect Tec.hntque . 

100r---------------------------------------------------------~ 

... 70 ~ 

~ 

... 

z 

... 60 v 

"' ... 

.... 

... 

> 

... 

... 

c 

~ 

~ 

X 

~ 

u 0 0 INDIRECT 

20 e e DIRECT 

10 

0 

0 20 40 60 80 100 120 140 160 180 ~00 

LOCATION ERROR ("ETERS) 

Figur~ 5 • Cumulative percentage of location error: 

AN/APQ-97 imagery--a points. 

I AN_/APQ-1.52 Imaserr. Table 12 shows the 1e rror means for the 

AN/APQ-152 imagery, A points. Though the mean for the Direct-1st was 

somelo~hat lnrger than that for the Indirect-1st, there was essentially 

no diffe r ence on the 2nd trial. 

-23-
Table 12 

MEAN LOCATION ERROR (METERS) FOR THE AN/APQ-152 IMAGERY--A POINTS 

TRANSFER ORDER MEAN 

TECHNIQUE 1st 2nd TOTAL 

DIRECT 31.5 23.6 27.6 

INDIRECT 21.5 24.2 22.8 

MEAN 

TOTAL 26.5 23.9 25.2 

An analysis of variance (Table 13) c;hot.JeJ t hat the effects of 

Technique and Order were not statistical!)' significant. In nddition, 

a t-test of th~ diffe rence bett.,cen tha Direct-1s t anJ Indirec t-1st 

means did not appraor.h s tatistica l significance (t=l.07, f~9 :a t-ratio 

of 2.26 is required for significance a t the .OS level). The data from 

the two techniques were combined. 

Table 13 

ANALYSIS OF VARIANCE OF LOCATION ERRORS (r1ETERS) 

AN/APQ-152 IMAGERY--A POINTS 

SOURCE df MS F - Between 

Subjects 8 

Groups 1 126.0 < 1. 00 

Subj.w.Groups 7 191 • 2 

Within 

Subjects. 9 

Method 1 97.2 1. 59 

Order· 1 29.5 <1.00 

Error (within) 7 60.8 

-24-
Figure 6 shows the cumulative percentage of location error for 

the AN/APQ-152 imagery, A points. The median error was 21 meters. 

100 

to 

10 

~ 70 c 

... 

z: 

~ 60 

... • 

.. 

... 50 > 

... 

-

~ 40 ::II 

II: 

::II 

"' 30 

20 

10 

0 

0 10 20 30 40 50 60 70 

lOCATION ERROR ("ETERS) 

80 90 100 

Figure 6 • Cumulative percentage of location error: 

AN/APQ-152 imagery--A points; Direct and Indirect 

Technique combined. 

Table 14 sh0ws the error means for the AN/APQ-152 imagery, B 

points. The larger mean total for the Direct compared \-'1 t h the Indirect 

Technique and for the lst compared with the 2nd trial was due, in part, 

to the large Direct-1st condition. But, note also that both the 1st and 

2nd Direct means were larger than the corresponding Indirect means. 

-25-
Table 14 

MEAN LOCATION ERROR (METERS) FOR THE AN/APQ-152 IMAGERY--8 POINTS 

TRANSFER ORDER ~1EAN 

TECHNIQUE 1st 2nd TOTAL 

DIRECT 87.2 53.2 70.2 

INDIRECT 23.8 30.5 2i.2 

MEAN 

TOTAL 55.5 41.8 48.7 

An analysis of variance of the data showed that only the Technique 

effect was statistically significant (p<.OS). Becat~e bo th Direct means 

were larger than the corresponding Indirect means, and because of the 

significant Technique effect, the data from the t\olo techniques were not 

combined. (Sef- Taole 15.) 

Table 15 

ANALYSIS OF VARIANCE OF LOCATION ERRORS (METERS) AN/APQ-152 IMAGERY--B POINTS 

SOURCE df _l1L F 

Between 

Subjects 8 

Groups 1 1845.0 2. 01 

Subj.w.Groups 7 915.9 

Within 

Subjects. _1 

Method 1 8246.2 9.00* 

Order 1 954.7 1.04 

Error (within) 7 915.9 

*p<.05 

-26-
Figure 7 shows the cumulative percentage of location error for 

the AN/APQ-152 imagery, B points. The median error was 54 meters for 

the Direct Technique and 22 meters for the Indirect Technique. 

100 

tO 

10 

., 

w 70 411: 

~ 

..: 

w 60 u 

"' w 

~ 50 w 

> 

-

~ 

411: 

_, 40 

::t 

E 

::t 

u lO 0 0 INDIRECT 

I e DIRECT 

20 

10 

0 -..L. 

0 lO 60 90 120 150 180 210 

LOCATION ERROR (~EYERS) 

Figure 7 Cumulative percentage of loca tion error: 

AN/APQ-152 imagery--a points. 

Table 16 s hows the error means for the points located in 

mountains. \o!ith the poss ible e xcept ion c.>f thl' Dire ct- 2nd condition, 

the error means •.o~ ..!rc considerably large r than thos~ fo r the n points. 

Large r errors w~rc ~~pcc ed for these points bec aus e of the lack of 

visual r efer ence points. The smaller tr.e an error for Lhe Direct- 2nd 

condition may have been a r esult o f the subjects ·becoming ve ry f::uniliar 

'"'i th the terrain features because they u·:>cd the Indirect Tcchn lque fimt. 

11te Indirect Technique r equired a more thot·ough search o f t he scene for 

identifi able features t h an did the Direct Techn ique because of the need 

for ma ny control points. 

-27-
The results in Table 16 seem to suggest that the use of the 

Direct Technique after considerable familiarity with the scene, may result in smaller location errors than the Indirect Technique. 

Tabl e 16 

MEAN LOCATION ERRORS FOR THE 

AN/APQ-152 IMAGERY--POINTS IN MOUNTAINS 

TRANSFER ORDER MEAN 

TECHNIQUE 1st 2nd TOTAL 

DIRECT 147.0 68.4 107.7 

INDIRECT 148.9 177.8 163.4 

MEAN TOTAL lllS. 0 123. 1 135.6 

TI1ough au a nalysis of variance (Table 17) ind i.c.at~d that the 

effect of Tcchniqu~ w~s st~tistically sign i ficun t (p<.05), it is 

apparent from Table 16 th~L this was due pri.tt1a r.ily to the small~r ~an 

error foe the Dircct- nd condition. Tt \oo uld seem sate to conclude 

that the location error for these points .i.s large ~nd the use of the 

Indirect 'fer.hl\iquc doe:; not result ln sm<.1l ler location ..-. r rors, and, 

ln fact, may r e sult in larger locatlon errors. 

-28-
Table 17 

ANALYSIS OF VARIANCE 

OF LOCATION ERRORS (METERS) AN/APQ-152 IMAGERY POINTS IN MOUNTAINS 

SOURCE_ M.. MS F 

Between 

Su6j ects 8 

Groups 1 12828.2 4.05 

Subj.w.Groups 7 3168 . 7 

Within 

Subjects 9 

Method 1 13751.6 6. 22* 

Order 1 2750.1 1. 24 

Error (within) 7 2210.0 

* p<.05 

~1/ ~\S 2~1:.!1\:tS~.! · Tablt! 13 s hm.,rs th~ mean errors for t h\! 

. A~ S- 24 i mage r y , A poin ts. It is :tpp:trent (n.>m the r e t ults that there 

w&s l i ttle difference b~t\,, ecn the me :l n tut<1l::; for t he t 1vo Tcchni.qut•s. 

Table 18 

HE AN l 0 CAT I 0 t! ER R 0 R ( f.! E T E R S ) FOR THE AN/AAS-24 Ir1AG ERY--A POINTS 

TRANS FER ORDER MEAN 

TECHNIQUE 1st 2nd TOTAL 

---· DIRECT 1 4 . 1 9.7 11.9 

INDIRECT 11.8 I 14.0 12.9 

f·1EAN 

TOTAL 13.0 11.8 12.4 

- 29-
~~~ ~~~~~~~~

An anal ysis ot varian ce (Table 19) indicated that none of the

effects we re statisticall y si gn ificant. Tine data from tine two techniques ore combined .

Table 19

ANALYSIS OF VARIA NCE OF LOCATIO N ERRORS (METERS)

A N /AAS— 24 IMA GERY—-A POINTS

SOURCE df MS F

B etwe - n

Subjects 8

Groups 1 54 . 1 1.55

Su bj .w .Groups 7 34.9

Within

SubjectsMe thod 1 4.3 <1.00

Order 1 5.5 <1.00

Error (within) 7 8.7

Figu re 3 shows Line cutnulative percentage error for tine \

~~/ A A S — 2-~ inage r

~

.- , A points. Tin e median erro r was 11 ~

- et e rs.

—30—
r ~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

- 

~~~~~~~~~~~~~~~ 

- _

100

90

80

70

“a‘-a

~~~5 0 .

I-

~~~4 0 .

‘-a 30

20

10 -

0 I I I I

0 5 10 15 20 25 30

LOCATION ERROR (MET ERS)

Figure 8 . Cumulative percentage of location error:

/

~

N/MA S-24 imaqery --A points; Direct and Indirect

Techn ique comb ined .

Table 20 shows the erro r means for the AN/AAS—24 imagery , B

points. Tho ugh the d i f ference between idn o Direct and Indirect mean

totals tin ; small (3.’n meters), an analysis of variance (Table 21)

indicated that onl y Technique effect was st~~t istiri11v si gnifican t

(p < .Ol), The data from tine two techni ques were ~ot combined.

31
Table 20

MEAN LOCATION ERROR (METERs)

FOR THE AN /AAS -24 IMAGERY - -B POINTS

- 

TRANSFER ORDER j MEA N

— 

TECHNIQUE 1 st 2n d TOTAL

DIRECT - 

- 15.5 13.8 14.6

1 

INDIRECT 9.3 1 9 __ 11.2

TOTAL 12.4 jl3 .4 12.9 

—

Table 21

ANALY SIS OF ‘/ARIA N CE OF LOCATION ERRORS (METERS)

AN /AAS— 24 IMA GERY —— L3 POINTS

— SOURCE df MS F

Between

~~ Jects 8

Groups 1 32.4 1.05

Sub j.w .Groups 7 30.7

WI t hi

Subjects 9

Method 1 54.4 13.27**

Order 1 4.4 1.07

Error (within) 7 4.1

** p< .O1

—32 —

~

_ - --- - -

~

-

~ 

-

~~~~~-
Fi gure 9 shows tine cumulative percentage of location error

for the AN/A~

-\ S—24 , B points. The median error was 14 meters for the

Direct Technique and 10 meters for the Indirect Techni que .

100

90 -

80 -

“aa-,

I—

‘-I

a

ta SO

a-.‘—j 40

30 . 0 —0 INDI RECT

s- • DIRECT

20

It) -

0 I~ j I I I ~~.. .j I —

0 5 10 I S 20 25 30 35

L O CAT ION ERRO R (M ETERS)

Figure 9 . Cumulative percentage of location error:

AN/AAS-24 imagery --B points.

AN / \A S— 27 r

~i:~-~~ rv. Table 22 shows t t i i - err °r mens a for the

A~

-

~/ I t~\ S—2 1 iflhI~’,O rv , A point;. The di i t e rence between t he mean tot a ’ S

for the Direct and Ind ir e ct Techni qut s and tine 1st and 2nd trials was

small.

—33—
- - ~

-- - - ~~~~~~ -

~~~~~~~~~~~~~~~ -~~~~~~~~~~~~~~~~~~

Table 22

MEA 1-

~ 

LOCATION ERROR (M ETERS )

FOR THE AN/AAS-27 IMAGERY --A POINTS

TRANSFER ORDER __~~J MEA N

TEC HN_IQUE ist f __

2nd~~~~I 

TOTAL

DIRECT 14.2 20.4 17.3

INDIRECT 18.0 13.2 15.6

TOTAL 16.1 l6 .8~~~~~ l6.4

An analv o is of variance (Table 23 ) indicated that none of the

effects were statisticall y signifi e:nt . Tine data I i-om tine two tecinni—

ques were c rib ii; ~ (I.

Tab ln~ 23

ANALYSIS OF V ARrAN CE OF LOCAT ION ERRORS (~-lETERS ) ,- \N/AA S — 27 I

~1AG E RY ——A POI NTS

SOURCE df MS F

Bet we en

Subj ~~c.ts 8

Groups 1 132.9 3.73

Sub j .w.Groups 7 35.6

Within

~~~ject s- 9

Method 1 12.3 <1.00

Order 1 2.1 <1.00

Error (w i t h i n ) 7 37.9

—34—

I—

I- — - - 

. — _--- - --- . —

— — --—- — — ~~~~~

_ _ -_ .

~~~ -— -— — 

___ i~~

_~ ~~~~~~~~~ ~~~~~~~~
Figure 10 shows the cumulative percentage of location error

for the AN / AAS—27 imagery , A points . The median erro r was 1 meters.

100 —_____________________________________

90

80

“a 10 ‘3

~~ 60 -

t2

j

~~ 30

10 

~ -DO-— - - -

~~~~ 

--

LOCAT IOII ERROR ( P ET ERS)

Figure 10. Cumulative percenta ge of location error:

A N /AAS —27 imagery--A points; Direct and Indirect

Techniques combined.

Table 24 ~1;ows the error means for the -\\/.o\S—27 i;-tie;erv , B

points . The mean total for tine DLreet iechni qu e - a s si igin t 1’: large r

than that for tine Indirect Tecinnique and that t or the 1st t r ia 1 was

slightly large r than that [or the 2nd trial.

—3 5—

Li _~~~~~~~~~~~~~~~

~ •
- ~ — - 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~

_ --—

~~~~~~~~

—_---- _ 

~~

—

Table 24

MEAN LOCATIO N ERROR (METERS )

FOR THE AN /AAS -27 IMAGER’(-- B POINTS

- 

TRANSFER ORDER t-~EAN

TECH N I QUE - 

1st 2nd TOTAL

DIRECT 36 .9 36.1 36.5

- 

INDIRECT 35.7 26 .4 31.0

MEAN

TOTAL 36.3 31.2 33.8

An a r nlvsls of variance (Table 25) showed tinat none of the

effects we re statistically si~~

iii f i c a nt . The data from the two tech—

niqua s we re combined.

Table 25

ANALYSIS OF VARIAN CE OF LOCATION ERRORS (METERS)

AN/AAS-27 IMAGERY --B POINTS

SOURCE df MS F

B ~ t~ i’~ ~i’fl

Sub ~i ects 8

Groups 1 81 .02 <1.00

Subj .w .Gr oups 7 88.3

Wi thin

C I- 4- ,-

~~~ 1 It _ C L )

1 132.0 <1.00

Order 1 100.0 <1.00

Error (wi thin) 7 138.87

—3 6—

L - - ----- -- ~ - 

.

- - _ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ : - -
-U ,

Fi gure 11 shows the c~unu1ative percentage of location error for

the AN /AA S— 27 , B po ints. Tine median error was 31 meters .

10C

90 -

80

~~ 7~) -

.

~~ a—

:

~ 

60

“a

a

“a 50

a-

~ 40

x

“ 30

20 -

10 -

Q I I I I I I I I

0 10 20 30 40 50 60 70 80 90 100

LOCAT ION ERROR (M E TERS)

Figure 1 1 . Cumulative percentage of location error:

AN /AAS-27 imagery-- B points; Direct and Indirect

Technique combined.

TV irna~ erv . Only tine Direct Tachni que was uned wi tin TV disp lay

of tine ver L i ~~

a1 p hotograp h. Consequentl y, onl y t u e cumulativ e perce nt age

of erro r Is reported for tine TV irla g ery .

Fi gure 12 shows tine cumulative percentage of location err or for

the [V ir -lbcr y . The me dian erro r w~ia 9 meters for the A points and

13 meters for the B points.

—3 1—

L -

~~~~~~~~~~ - - -~~~~~~~~~~ - ---—
- -

100

90-

80

~ 70 .

~~ I—. 0

~ 60 -

(A. .

a

“a 50

0

~ 40 -

x

‘a 30 . 0 - ~ 0 B p o i n t s

20 • A po int s

10 -

0 _1 I 1 I

0 5 10 15 20 2 5 30 35

LOCATIO N ERRO R (METERS)

Figure 12 . Cumulati ve percentage of location ~rror:

TV ima gery .

Potut Tt~ausIer Time s

~ c t ~i t I

~rc- ; taken to transfer t~ne A and B ~~ i ots from eacin tvp& ’ of

image r~ to the i hn ta base were comparable so tine times for the A an d B

points we re combined.

Table 26 shows the mean time taken to t r l n ~~ter points Ira -i each

type of miss ion i r a g c rv . Across all t vpt-s of mission i i - e - .e ry , except

tine TV , tie mean t i ir,c was 1. 3 r n i n ut .-s [or the Di i ect loclani que and

about 6.5 minutes for the Indirect l o c hin n i qint - . Depending en the type

of miss ton Iir ~

-l g,t ry, it took f rom between nho ~~t 4. 5 to 6 Lime s longer

to transfer the points using the Indi rect Technique than i t took us ing

the Direct Techni que . This result was expected in that t i c - Direct

Techn ique r equ ires the subject to t ransfer I point and the Indirect

Tech nique requires him to transfer 4 to 6 points.

—38—
‘II

Ta ble 26

MEAN T J I

~E (MI NUTES)

TO TRA NSFER POINTS

FROM EACH TYPE OF MISSION IMAGERY

MISSION TRANSFER TECHNI QUE

IMA G E RY —_____________

______ ________ 

DIRECT INDIRECT

AN /APS-94 1.4 6.5

~ 

AN /APQ-97 1.6 7.7

“) AN /AP Q-l52 1.4 7.5

AN /AAS-24 0.7 4.3

A N /AAS - 27 1.4 6.3

TV .9 N/A

SUMMARY AND DISCUSSION

Table 27 is a summary of the location error results. The

tible shows , for each type of mission imagery and for the A and B

points separately, whether or not the two transfer techniques were

combined in computing the cumulative percentage distribution , and the

location errors , in meters , corresponding to each of three selec ted

cumulative percentages. Each percentage and corresponding loca tion

error m ay be interpreted as follows . For example , cons ider the

A \/APS— 94 imagery, A poin ts: 25Z of the errors were less than 21

meters , SO~

i were less than 2+ meters , and 75% were less than 52 meters .

-39-.
Except for the AN / APQ— 97 imagery , the results showed that the

effect of Transfer Technique for the A points was not statistically

significant for each type of IR and SLAR imagery . Even though the effect

of technique was significant for the AN /APQ—97 , the data from the two

techniques were combined because of the reasons stated previously in the

Results Section. Consequently , Table 27 shows only the combined indirect

and direct errors for the A points for each type of IR and SLAR imagery.

The indirect transfer of A points was not significantly be tt er than

the direct transfer probably because of the accuracy limits imposed on

both A points and control points . That is , because useful control points

must also be on identifiable features , they carry the same problems of

transfer as do A points.

Wi th the exception of the AN/AAS—27 imagery , ind irect transfer of

B points improved location accuracy . For the AN/AA S—24 , the AN /APQ—97 ,

and the AN /APQ-l52 imagery , the indirect transfer accuracy of B points

was comparable to the transfer accuracy of A points . For the AN/APQ-94

imagery , indirect transfe r (median error , 54 meters) was more accurate

than direct transfer (median erro r , 75 meters), but indirect transfer

of B points was not as accurate as the transfer of A points (median

error , 34 meters).

The AN /AAS—27 image ry presented some unexpected problems , especially

wi th the indirect transferring of B poin ts . The image was extremely

cortt rasty ; the main—made objects (roads , railroads , b uild ings , airstrips ,

etc.) and bodies of water we re alm ost white and the intervening areas

were very dark . Several of the B points were in the dark areas where

few surro und ing con t rol po 4 nts could be f o umd . In s

~~~o ~~~~~~~~ control

points could be found only on one side of the point of interest. Most

of the points th~~t exhibited large indirect transfer errors also had

large t ransformation residuals , wh ich means tinat the subjects could not

find good con trol points. In addition , thc ima gery was so compressed

near the ed ge of the format that the six—parameter transformation

program apparently was inadequate for transferring points in these areas .

The results indicate that experienced operators can transfer

points from operational infrared image ry (AN/A AS— 24) and from TV image ry

of vertical photograp hs with acceptable accuracy . Regardless of the

tr~~’-~~er technique used and the type of point transferred , 75% of the

locatioI~ erro rs we re less than anout 20 meters.

As expected , the location error for the SLAR image ry , and particularl y for the lower resolution AN/APQ—94 image ry , was larger than it

was for the IR and TV Imagery . But , even the location accuracy of points

transferred from SLAR imagery may approach acceptable limits if the

opera tor is g iven a means for indirect point transfer. This Is particularly true fr the higher resolution radar imagery (ANIAPQ—97 and

AN/APQ—152). Disregard ing the type of point , 50% of the errors were

less than about 30 meters and 75% were less than about 50 meters . For

the lower resolution radar image ry (AN / APs—94 ), 50% of the errors were

less than about 55 meters and 75% were less than about 65 meters .

‘

~o-a~tainous areas present special pr oblems for analytical transform ations. All types of remote imaging syste~ns (photo , IR , SLAR )

—40—
-

~~~~~~—~~~ ~-

~~~-~~ - -

Table 27

SUMMARY OF RE SU LTS F O R LOCATION ERRORS

MISSION IMAGERY POINTS T R~~~~~E

~ E 

ERROR (

~~ETERS)

E 25% 50% 75%

A COMBINED 21 34 52

A N/Aps-94 

— 

DIRECT 39 75 130

INDIRECT 35 54 64

A COMBINE D 16 29 48

DIRECT 34 56 93

AN /APQ -97 —-— ______

0 INDIRECT ~~ 27 39

A Cm-1BINE D 11 21 39

DIRECT 30 54 90

B 

INDIRECT (2

A CO~-~B IN [D 6 11 16

DIRECT 8 14 22

B 

IN DIRECT 6 1 0 15

A COMBINED 8 15 30

A N /i’

~

AS-27 B COMBIN ED 17 31 53

A DIRECT 5 9 1 8

TV B R ECT 8 13 20

—4 1—
produce imagery having displacereents due to terrain relief. For example, 

the image of a mountain peak is displaced away from the photo or IR 

sensor and towards the radar scnsor.j/To make a proper analytical transformation the control points must be at approximately the same elevation 

as the point being transferred. Special techniques must ba developed 

to be used in mountainous areas. 

There is little doubt that indirect transfer improves location 

accuracy of targets that are not located on features identifiable on 

both the mission and data base imagery. But this improvement is achieved 

at a cost in the time it takes to make the transfer. The results shol.ted 

that it tn.'<es about five times longer to make an indirect transfer than 

it does a direct tran~fer. Averaged across the mission imagery, the 

mean time taken to transfer points was L 3 minutes for tile Direct Technique and 6. 5 minutes for the Indirect Technique. Whether or not the 

improved accuracy warrants the additional time required would seem to 

depend on the operational context in which the transfers are made; that 

is, the accuracy required and the time available to transfer targets. 

The data reported here were based upon what was judged to be 

representative samples of imagery from remote sensors and upon "experienced" 

operators. Even so, the data should be interpreted in light of several 

considerations. Point location accuracy is certa.i.nly related to the 

amount of detail available in the m.i.ssion as well as the data base imagery. 

The amount of detail in the SL.\R and IR irnagt~ry depends not only upon 

the kinds anJ numbers of natural and cultural features but upon the 

settings(gain, dynamic range) of these equipments. In addition, 

location accuracies may be iu;proved by having operators make repeated 

:f:1dir0-:t r.:-~:3f~rs , u:;lng diffcr..:nt con:blnotion:.; ... nd ,,u,;;liers of Cv•l t.:ol 

points, ~d select thoGe points that produce the smallest residual. 

Furthet111ore, additional training of the operators may i iaiprove location 

accuracy. Another important consideration is the w:Jy in \Jhich the 

school solution of the targets .l3 derived. When the sdwol soluti.on is 

establisheJ independently of true ground control, as it t·ms in the! present 

Gtudy, there is the possibility of C! rror in establishing the true posttion 

of some poi.nts. 11lis may occur because of possible idcn::1ficati.on problems: 

one cannot be ccrtai.n altJays thnt an image !:l~~lectcd in the SLAR or IR 

record and the one selected i n Lhe data base photograph are from the 

same object. Because of this potential difficulty, obviously the school 

solution should be bas ed upon true g round control whene ver possible. In 

s ummary, then, the results report~d here de pend in part upon the ;cene 

imaged, the sensor settings, operator experience and procedures, and the 

way in which the true positions of the points to be transferred ~.:ere 

established. 

,- rdtet dhO'l•c-t 

ru. pla:-. 

Relief Diaplae~ent (outvard) - Photo and lR Relief Displaee~nt (invard) - Radar 

-42-
CONCLUSIONS 

Baaed on the results of this study and related experience it is 

concluded that: 

• 

• 

.. 

• 

• 

The optical-mechanical rectifying or scaling equipment 

evaluated was found to be far less useful than an 

analytical transformation. 

Electronic image manipulation methods are impractical for 

meeting the point transfer requirements associated with 

APPS operations. 

Indirect as well as direct transfer techniques arc need~d 

by the APPS operator for transferring points from a 

variety of records from remote reconnaissance sensors. 

Point transfers can be made with useful accuracy to a photo 

data base from radar and infrared reconnaissance imagery 

having a wide range of scales and ground resolutions. 

Point transfers can be made with acc~ptable accuracy from 

a static TV display of ve rtical photography to a photo 

data base. 

RECO U>lENDA TIONS 

It is recommended that: 

• 

• 

• 

An indirect point tr:msf e r s ubsys t em be developed f ully, 

i ncluding equipment modil.'ic.:1 tions , ond be maJe available 

to APPS operators. 

In future tests, true ground coordinates be es t abl:i.shed 

for all points of interes t. 

Further studies be made with t elevision mission image ry 

including simulated, -tiu1~ dynamic imagery. 

Techniques for transferring poi nts in mountainous terrain 

be developed. 

-43-
APPENDIX A 

A!xALYTICAL PllOTOGRANNETRIC POSITIONING SYSTF.:~I (APPS) 

The Analytical Photogrammetric Positioning System (APPS) is a 

point positioning system developed at the US Army Engineer Topographic 

Laboratories (USAETL), Fort Belvoir, Virginia. The APPS has evolved 

a s a solution to the problem of determining X, Y, Z coordinates of 

points of interest any·,...here in or forward of a Corps-size area in a 

matter of minutes. 

Photogrammetr ic theory and techniques have been combined \o~ith the 

capabilities of a desk top programmable calculator to provide for 

utilization of the analytical methods of determining position, unlike 

the more clas5ical a.1alog methods found in photogt'ammetr ic map 

compilation instruments. The problem is treated as an intersection 

problem for which universally accepted solution techniques are 

available. Numerical data are accepted for certain known parameters 

and measured photo coordinates are treated as the obsc!rvcd parameters, 

thereby solving for the unkno\o~n X, Y, Z coordinates of a poi.nt. 

There are two parts to the APPS; (1) a Data Base (DB) consisting 

of mapping quality aerial photography and its associated numerical 

data, and (2) an as:.l;!mblage oi mcnsm·ution and data processing cquipmC'nt 1,.; th n s n•)C i .:lt crl <:: •>ft~·.';;lre. 

The DB is the k~y element of the APPS. It is rigorously prt>pared 

as part of the normal ma pp i ng p~ocess a nd un ly the n extr~c tcd from 

that proc.:!ss for iippli..:a tion to the APPS. The DB is math~~mutlca] ly adjusted by an ~lnalytl, ;~ l pror.cdur e knm·JO as aerial b.l0c.k trian ulaLion 

\.•hlch is b<1 sed upon th~ me thod of l east s~u~ res. Given t\-10 poi nts of 

!<no\vn horizontal p0sicions (X, Y) and three points of kuo~ n elevation 

(Z), one c :!•l determine the slx orientation pa rameters u( a photograph, 

\vhethet' dc:>aling \lith one ovcrl.:lpping pair of photugraphs or ov~rlapping 

covera~e or entire countries. Use is made ot r edundant control data 

whe never possibte to reduce accumulation of small uncorrected ;;;ystcmatic 

errors nd random errot·s. The adjustment is held to ground control. 

Tne DB photogt'aph requires no spec ial proccssinR such <lS rectification. 1t is 01nnotar:cd \v ith orientation p0ints called index points 

and \o/.ith ch~ck points. Its associated numer leal data includes i11Lerior 

and exterior orientation parameters, photo coordinates of the index 

points, <1nd geocentric coordinates of the check points. APPS equipment 

calibration parameters are also incorporatt.!d in the numt.!rical data. 

The other port lon of the APPS, the h<1rdware, is primarily an 

assemblage of commercial. off-the-shelf it~ms that \.zlll accept the DB 

a·nd perform the necessary measurements and computations for X, Y, Z 

-45-
coordinates. The current package represents first generation components. Modifications and add-ons have been envisioned to increase the 

flexibility of the system. 

There are five major component items of equipment to include: 

(1) a modified Zeiss Stereotope¥ (2) an operator control box, (3) an 

interface unit, (4) a Hewlett-Pac~~rd~(HP) 9810A programmable calculator-Y and (5) an HP cassette memory¥ See Figure Al. 

The Stereotope provides the capability for stereoscopic viewing 

and parallax measurement by the X, Y and X-parallax motions it possesses. To extract these measurements, a Bendix X, Y digi tized data 

gridYis installed under the Stereotope baseplate and a signal cursor is 

connected to the moveable photocarriage. Also, a shaft angle encoder 

is connected to the X-parallax motion drive. 

The operator control box provides a simple means of selecting a 

particular operation for the APPS to perform, i.e., zero the baseplate 

data grid datum, or index the DB stereomodel, etc. 

The interface unit converts cursor signals to the HP language and 

subsequently HP language to a desired output language. 

The UP 9810A programmable catculator and the HP cassette memory 

function together. The ~ncmory holds the soft•vare prograllUl\ing and DB 

files on t~pe covcrinz a Corps size area for sequential access by the 

calculator. · The calculator uses the program and one numerical DB file 

.:!t.:! tl :~ o;~,.!!: !cr :·:lt:t the i!~pu t f .. :: Lhc ~L:Jr :..\,;l-! =. r~ u;;!1 tlt~ 

interface to compute the X, Y, Z coordinates of a poi nt. 

In prac tice, the operator uses a photo index ove rlay t o determine 

uhich DB stereo pair of photo ra hs t o place on the Stercotape. He 

j ns~t·t:.; the magnet lc ~p e cnss(.'t te containing the progr:1r.1 <And DB 

muneri eal data f ilcs for that model lnto the cassette r.t uo ry. He then 

ctiv<lt~s the cassette memory to loa d the proeram by use of a mag'1ctic 

card . The ca rd also contains th ~ Ster eotope calibration par ameters 

ment ioned earl ier. He then calls in the DB file for the model being 

used by keyboard couunamls. Each pho to o i the mode l is o r1.1'!nted independently us lng the i ndex poi~t s mentioned cm:lier. 1 he photo coordina tes of four index poittts a r e rnc ·:::c:ureci :1nd a transformation computation tr.adc to relate th\'! m~a.,ured photo coordina tt>s to the adjusted 

photo coordinates. The opet.ltor t hen t"'bscrves a nd measur es a check 

point, th is time in stereo, to asc.erta.in th.-:lt he corrcr.tly oriented 

the model. He must <lgree with th~ known coordinates of the check 

point '"i thin establ ished tol et·:-,nct ~::; he fore he can proc~l d. Once he is 

s1g a~lled to proc~~d he then bs~cvc~ the puint of int~r~st, mea sures 

nnd computes the X, Y, Z coord ina tcs of the point and ol.tain!> a printout on pa per tape of the CT!i Z0ne, l~s ting, orthin~ and c l.!va tion i n 

meters • 

.Ycommerlcal or trade n.:-tM£'5 are r,ivcn only in the interest of precision 

in reporting experi.:r:enl:al proct!dt~r s. Usc of the namt.!s does not constitute official endorsement by the Army or by the U.S. Army Research 

Institute for the .Oeh;worial awl Social Sciences. 

-46-
-

~~ )i

-; ‘a . -

- -

TT 

- 

‘ 

- - 

I

_ l

i,.. 

~~~~ 

- 

U

?~

4~

I)

I ___

______

: I 

~~~ - ----~~—--- ~~~~~ -- 

. 

~~~~~~~~~~~~~~~~~~~ ~~~~~~~ ---~~~ -~~~~~ _ _:=:- 
_______ -

~~~~ -~~~~~~~~~~~~~~ - - -

Test results conclude that horizontal position locations determined with the APPS are approximately equivalent to third—order ground

surveys , This is readil y achieved by personnel having previous tra ining in the interpretation of aerial p hotograp hs and additional 16—40

hour s instruction on the APPS .

The APPS is packaged for transport in three mili tarized carry ing

cases for a total wei gint of 478 pound s and a volumu e of 27.42 cubic

feet. It requires 600 watts of power at llOv , 60 Hz.

— 48— —

I —a-—--

- ----—--- -- -

~

. - — - - --- - 1_______ ___~ ,T~~~Tr~ - ___________
APPENDIX B 

INVESTIGATION OF ALTERNATIVE TARGET TRANSFER TECHNIQUES 

Three general a~eas were explored in search of new transfer techniques or equipment: 

• Optical-Mechanical Equipment 

• Electronic Image Correlation Techniques 

• Analytical Transformation Technique 

Optical-Mechanical 

Several types of instruments fit into this general classification. 

Most of them are able to change the magnification of one or both photographs but cannot achieve attitude rectification. Four such instruments 

were examined. The Multi-Sensor Take-Up Table (MSTU) with Bausch and 

Lomb Variable Stereoscope is a back-lighted glass surface with railmounted optics. The optics have the capability to rotate the image and 

to vary the magnification in each optical train. Magnification ranges 

are: 3.5X to 15X; 7X to 30X; and 14X to 60X, depending on eyepieces 

and lens attachment selected. 

The f.acey-_!..~ci, commonly used in photographic l aboratories and 

f or gr:lphic arts, .is a very simple instrument with a phoLogr a t>hic .image 

plane moved by c rank handles for ma8nifying or r educing within a 

±4-power range. Corr elation between mission imagery and data base could 

be "lGCOioplished \-lith thi s .instrument, but the final re ~olution on the 

vi e~-ling screen ''"'as well below useable limits. No rectification for 

differential attitudes was possible with this instrument, so only near 

vertical photographic data could be used. 

The B&L 7.o~ Transfer Scope (ZTS) is a table-top instrument used 

to superimpose :l.mnges from l\oiO different graphics. One graphic (Sl.AR, 

IR, or photo imagery) is placed in the 9" x 9" plate holder and the 

other (data base ) is placed on the table under the ZtS. Zoom m~gnification, continuous from lX through 14X, provides r apid, accurate matching of mission t magery scale to data base scale. An anamorphic lens 

sy~tem enables the instrument to compensate for some of the geometric 

anomalies in an :image. A dial control selects the direction and a 

lever controls the enlargement ratio (stretch) from 1:1 to 1:2. The 

i ns trument provides the means for rotating the image from the plate 

holder through 360°, as an aid to the operator in making the critical 

final adjustment. After the two images are superimposed, a point of 

interest appearing on the image in the plate holder can be transferred 

to the data base by use of a Snap Marker or a simple marking device. 

The ZTS is capable of making geometric and scale changes so one 

photo image will correlate with another photo image of the same area 

-49-
if the relative attitude between the two images is not too great. For 

small areas, SLAR and IR images also can be restituted into a photo 

data base. A crude correlation could be made between the mission and 

data base imagery, but the correlation was not sufficiently accurate. 

Usually there was a great difference in the ground resolutions of the 

two images and the sharper image dominated the scene so much that a 

correlation to a few mils was usually difficult, if not impossible. It 

became even more difficult when non-photographic images were used. 

Furthermore the correlation process was very time consuming. 

The Bausch and Lomb Micro-Mark is a precision point transfer instrument with independent variable magnificution for each eyepiece. 

It provides optical rotation through 360°. Aft~r two images are correlated stereoscopically, or are superimposed, the point of interest is 

marked on each image by a heated die. Using this instrument with a 

variety of image tvpes and scales proved to be unsatisfactory for the 

same reasons found with the ZTS plus the fact that it has no restituting capabilities. Precise transferring of points between two photo 

images can be performed with this instrument if the differences between 

the scales and nttitudes of the two photographs nre not too large. 

Electronic Image Corre lation Techniques 

Electronic im:tge correlation t echniques have frequently been used 

in the past in photogrammetric instruments to automate th~ process of 

point transfer and to remove parallax ln er~o models. No~t of the 

successful appl i.c.lti.nns have been in i.nstr 1mr>n ~ ('-•signed to o~~r.:1te 

with similar imagery: i.e., photo to photo, SLAR to SLAR, IR to IR, 

etc. In addition, most of these instruments have a limited a~commodation range for scale va riations. 

In the gene rnl case, one \vould like to automatically match any 

type of imagery Hith any other nnd at 1-111 s cales. Such <.m :1m1Jitious 

undertaking is probably impractical; ho,_.ever, it might be instructive 

to make some estima t es as to how far this i.de a might be carried. 

Firat, one should re:tlize that matching SLAR to photo, or IR t o photo, 

or SLAR to IR, is prob.:Ibly impractical because of the excessive costs 

of s uch an instruiT'~nt. The problems tha t occur are due not only to 

geometry but also to the f ac t that the different sensors image the 

same scene in di ffen~nt wnys. This fuct is lvhy the diffe rent se11.;ors 

are useful but is al!3o precisely what would defeat any but the 111ost 

sophisticated auton:atic matchi ng ins trument. For example, a contrast 

change from dark to light in an IR record might not s hmv up a t all in 

a photo, and might show up as the opposite phase i.n a SLAR record. 

Therefore, if one wishes to automatically match mission ima~ery with 

a data base, it "''ould probably be feasible only \vhen the mi.ssi.on anc.l 

data base records a re from the same type of sensor. 

Assuming the data base is composed of vertical, frame photography, 

estim:ttes should be w.ade of the range of scale variations and the i mage 

distot:tion that might r equire accommodation in an automatic image correlator type instrument. Abcolute estimntes cannot be made becau$e for 

-50-
certain conditions of terrain slope and camera tilt the terrain is not 

imaged at all, and so the required range of compensation becomes infinite. One must assume certain conditions in the data base photography 

(scale, terr~in slope) and certain reasonable accommodation ranges in 

the correlator, and then determine the limiting cases for the reconnaissance coverage (A similar approach should be used for the SLAR-to-SLAR 

and IR-to-IR matching). 

Assuming the data base is composed of vertical, frame photography 

of the standard 6" focal length, 9" x 9" format, tht!re will be local 

scale variations due to terrain slope. These variations are a function 

of the terrain slop~ angle and the angle off the camera optical axis. 

For example, a 30° terrain slope at the edge of the format will produce 

a local scale factor approximately two times smaller than the average 

scale factor. 

The reconnaissance photography to be matched tilitb the data base 

will probably have a different average sca le factor, and if the photography is oblique or panoramic it to~ ill have local scale variatt ons. 

These scale variation~, due to the camera axis bei ng non-vertical, can 

be quite extreme for large angles off vertical. In the limit at the 

horizon, the scale is obviously i n finitely small. Thus, if the correlator has a finite scale accommodation ranee, the to~c p angle of panoramic photography or the inclination a ngle of oblique phot ogr a phy must 

be r estricted to certain angles from the ve rtical to s tay withi n Lhi s 

range . Panoramic p•lotography , for exawple , exhibi t:; a 2: 1 scal e change 

fcom nndir to 45., sweep angle. · Thus, the t o tal sr.ale a c-comnu)(lation 

r .1ncc 1111 have t o be apportll)n~cJ in a Hay to handle the av ag~ scale 

d lffl.!re nce bc t,_.e.!n the <.l.:1ta base photo i.l nd conn~ lssance photor.r aphy, 

and als o the s cale va riati.ons wi thi n e ach of the two plh.>tos. 

To arrlve .:1 t s ome ~; onab ~ ~s i.mat:e of th~ s cale ac ~..·ommo tion 

r.:1n gc of a corrcJator, consld(.•l:ation mu!i t be given to the pract kal 

lil'li ts of the compommts <tnd cir cuits that may be m:cd. The cot:re l a tion 

process its elf is tl!.!pendcnt on t·csolution and contrns t in ea ch of the 

two areas to be ma t ched. In other \-lords , one could have inf inite r esoluLi on, but i f the t:e t.,rere no contrast changes in the area unde r considera t i on, the proceus would f a il. From past experi ence and tests i t is 

reas on.1ble to believe that a correlator will product! .:1 r el i able output 

when sc<lnning an nr ea as s~tll a s 20 x 20 t:esolutJon elements in the 

photo having the .l o~ r resolution. In the case unde r dis cussion Lhis 

is probably the tlata base photo. The corresponding scan on the connaissance photo ~.,rouitl probably have more resolution cleme nts due to 

the generally better resolution and larger scale of this type imngery. 

Scanning of the photos to convert the density Lhanges into 

elcctri~nl sign<1ls can be accomplished by s everal techniques. But 

those that perform at high speed and reas on.:1blc cos t, s uch as fly:f.ng 

· spot scanners and i mage dissectors, are g.!ner.:llly limited by a s pot-todiameter ratio of about 1/1000. If it is assumed that the spot diameter 

is matched to the resolution element of the data base imagery, then 

there t-Tould be a 50 to 1 scale accoDDDodation range for the reconnaissance imagery. If a factor of 2 is allowed for the slope induced scale 

-51-
Vdriations and for the camera tilt, then about a 12:1 average scale 

variation could be acco11110dated. 

Transferring points by automatic electronic image correlation does 

not hold immediate promise for the variety of sensor record and exposure 

conditions that must be considered. 

Analytical Transformation 

The only approach that seems to hold any promise for a variety of 

reconnaissance sensors is an analytical transformation of points from 

one record to corresponding points on the other record. The procedure 

is as follows. Select 4 to 6 points ("control" points) surrounding the 

point of interest in the mission imagery. These points must be features 

identifiable in both the mission and data base imagery. Place the 

- ._ 

"Coot~ot• Potota)i 

...... " 

J'olat of -.. A 

JolOU:Jt .tl 

Mission Image 

... 

t .. . .. • • 

• 

Data Base Image 

miss Lon photograph in a comp:u.ttor and measure the image coordinates of 

the control points and the point of interest. Place the data base photogr.:tph in the comparator and measure the coordinates of the fiducials and 

the c:orresponding control points. Using a five-, ~ix- or eight-parameter 

tran=>formation program, transform the control po:i.nts and the point of 

interest into the coordinate system of the data base. 

When contt"ol points ctln be found reasonably close to the point 

of interest, the transformation can be made to abol't the same accuracy 

that the control points can be identified and "teasured. 

One of the tractiv~ features of thls approach is that analytical 

transformations can be used wi.th all types of mission i magery, such as 

VP.rtical and obltque frame photography, panoramic photography, infrared 

imagery and side-looking t"adar imagery. 

-52-
Further Considerations 

Points can be transferred stereoscopically with high accuracy if 

two images have similar ground resolutions. But if the ground resolutions 

of the two images are quite different, it is difficult to form a stereo 

model and the transfer accuracy suffers. Often two images of the same 

area, even with the same type sensor, are taken from approximately the 

same X, Y ground coordinate but at different altitudes so there is no 

significant parallax. The two images can be matched but a stereo model 

wtll not be formed, so transfer accuracy will deteriorate. Matching 

images from unlike sensors (for example, photo nnd radar) or matching 

two records differing significantly in ground resolutions is time consuming and the results are usually disappointing. If one desires to 

make such matches to g~t a stereo model, the best way to do so is to 

mark thr~e or more points on one record (near the area of interest) and 

to mark the corresponding points on the other record. Scaling and 

rectifying one record to the other can now be done to~ith much greater 

speed and accuracy (assuming the equipment is able to accommodate the 

attitude and scale differences). But because corr~sponding points must 

be selected to perform a good match, it seems more appropri.ate to 

measure the coordinates of the points and use the coordinates to perform 

an analytical transformation. 

-53-
DISTIIIUTION 

4 OASD lMioRAl 

2 HOOA CDAMI·CSZI 

1 HOOA IDN'E.f'IR 

HOOA IDAMA·ARI 

HQOA IDN'E·HRE·POI 

HQOA ISGRD·IDI 

HQOA CDAMI·DOT·Cl 

1 HODA IDAPC·PMZ·Al 

1 HODA IDACH·PPZ·Al 

1 HODA CDAPE·HREI 

HOOA CDAPE·MPO·Cl 

HOOA CDAPE·DWl 

HQOA (DAPE·HRLl 

HQOA CDAPE·CPSI 

HODA IDAFD·MFAl 

1 HODA lDARD·ARS·Pl 

1 HODA lDAPC·PAS·Al 

1 HODA lDUSA·ORl 

HODA CDAMO-RORI 

HODACOASGI 

1 HOOA CDA10.Pil 

1 Chief, Consult Oiv COA·OTSGI. Adelphi, MD 

1 Mil Ant. Hum R•. OODRioE. OAD lEioLSl 

1 HQ USARAL, APO S.1ttle, ATTN: ARAGP·R 

1 HO Forst Army, ATTN: AFKA·OI·TI 

2 HQ Filth Army, Ft S.m Houlton 

1 Dlr, Army Stf Studies Ofc, ATTN: OAVCSA CDSPI 

Ole Chief of Stf, Studies Ole 

OCSPER, ATTN: CPSIOCP 

The Army Lib, Plnt~~gon. ATTN: RSB Chief 

The Army lib, PentlgOfl, ATTN: ANRAL 

Ofc, Aut Sect of the Army CRioDl 

Toc:h Support Ofc, OJCS 

USASA, Arlington, ATTN: IARO·T 

1 USA RICh Ofc, Durham, ATTN: Life Sciencft Dir 

2 USARIEM. Nlliclt. ATTN: SGRD·UE·CA 

1 USATTC. Ft Cll'(ton. ATTN: STETC·MQ.A 

1 USAIMA. Ft Brlfl!l. ATTN: ATSU.CTD·OM 

USAIMA. Ft Brlll!l. ATTN: MII'Qulllib 

IJS WAC Ctr lo Sch. Ft McCielltn. ATTN: lib 

US WAC Ctr lo Sch. Ft McCielltn, ATTN: T"9 Dir 

USA Ouarterm~~ter Sch. Ft LM. ATTN: ATSM·TE 

lntellitence M1teri1l Dew Ole, EWL, Ft Holabird 

USA SE Signll Sch, Ft Gordon, ATTN: ATSQ.EA 

USA (;Npllln Ctr lo Sch. Ft Htmilton, ATTN: ATSC·TE· RD 

USATSCH, Ft Eustis, ATTN: Educ AdviUSA Ww College, Clrtlsle 811Ttcks, ATTN: Lib 

2 WRAI R, Neuropoychiltry Div 

1 DLI, SDA, Montetey 

1 USA Concept Anll Aor;v. Bethndl, ATTN: MOCA·WGC 

1 USA Concept ANI Aor;v. Bethesd1, ATTN: MOCA-MR 

1 USA Concept Anll Aor;v. Bethesdo, ATTN: MOCA-JF 

USA Artie Test Ctr, APO S.1nle, ATTN: STEAC·MO-ASL 

USA Artie Test Ctr, APO S.onle, ATTN: AMSTE·PL·TS 

USA AnNment Cmd, Redstone Arwn.l, ATTN: ATSK·TEM 

1 USA Ar.........,t Cmd, Rock lsllnd, ATTN: AMSAR·TOC 

FAA·NAFEC. Atlontlc City, ATTN: lihrl"f 

FAA-NAfEC, Atlontic City, ATTN: Hum Engr 8r 

1 FAA Aeron.utral Ctr, Okllhoml City, ATTN: :lv.C-440 

2 USA Fld Arty Sch, Ft Sill, ATTN: librory 

1 USA Armor Sch, Ft Knox, ATTN: Librwy 

1 USA Armor Sch, Ft Knox, ATTN: ATSB·DI·E 

USA Armo< Sch, Ft KNix, ATTN· A~ DT TP 

USA Armor Sch, Ft Knox,I\TTN: ATSB.CD·AD 

ARI Distribution list 

- 55-

2 HOUSACOEC, Ft Ord, ATTN: Librll'y 

1 HOUSACDEC, Ft Ord, ATTN: ATEC- EX- E- Hum F1Ct0<1 

2 USAEEC, Ft Benjlmin Hwrison. ATTN: Llbrwy 

1 USAPACOC. Ft Benjlmin Hll'rison, ATTN: ATCP- HR 

USA Comm-Eiect Sch, Ft Monmouth, ATTN: ATSN-I:A 

USAEC, Ft Monmouth, ATTN: AMSEL- CT- HDP 

USAEC, Ft Monmouth, ATTN: AMSEL-PA-P 

USAEC, ~t Monmouth, ATTN: AMSEI.-SI-CB 

USAEC, Ft Monmouth, ATTN: C, Ftcl Dew Br 

USA Mlteriols Sys Anal A.gcy, AberdHn, ATTN: AMXSY-P 

Edftwood Arsenol, Aberdeen, ATTN: s,.REA- BL- H 

1 USA Ord Ctr & Sch, Al'oordeen, ATTN: ATSL- TEM- C 

2 USA Hum Engr Lab, Aberdeen, ATTN: Librory/Dir 

1 USA Comblt Arms T"9 Bd, Ft Benning, ATTN: Ad Supervisor 

1 USA lnfontrv Hum RICh Unit, Ft Benning, ATTN: Chief 

USA lnfontry Bd, Ft Benning, ATTN: STEBC- TE- T 

USASMA, Ft Bliss, ATTN: ATSS- LRC 

USA Air Del Sch, Ft Blin, ATTN: ATSA-CTD- ME 

USA Air Del Sch, Ft Blia, ATTN: Toch Lib 

USA Air Del Bd, Ft Bliu , ATTN: FILES 

USA Air Del Bd, Ft Blin, ATTN: STEBD-PO 

USA Cmd 8o Generol Stf College, Ft LeiVIn-rth, ATTN: Lib 

USA Cmd lo Generll Stf College, Ft LeM!nwo<th, ATTN: ATSW-SE-L 

USA Cmd & Generll Stf College, Ft Le...,n-.th, ATTN: Ed Advisor 

USA Combined Arms Cmbt Dew Act, Ft Lt~wnwonh, ATTN: OepCdr 

USA Combined Arms Cmbt Dev Act. Ft LtM!n-.th, ATTN: CCS 

USA Combined Arms Cmbt Dew Act, Ft La-~1'1h, ATTN: ATCASA 

USA Combined Arms Cmbt Dew Act, Ft laM!~1'1h, ATTN: ATCACO- E 

USA Combined Arms Cmbt Dew Act. Ft ~ ... n~. ATTN: ATCACC· Cl 

1 USAECOM. Night Vosion L: b, Ft Belvoir, ATTN: AMSEL-NV-SD 

3 USA CompUter Sys Cmd, Ft Belvoir, ATTN: Toch Librwy 

1 USAMERDC, Ft Belvoir. ATTN: STSFB- 00 

USA E"9 Sch, Ft Belvoir, ATTN: librory 

USA T01>09'aphic Lib, Ft Belvoir, ATTN: ETL- TD- S 

USA TOPO!IIophic Lib, Ft Belvoir, ATTN: STINFO Center 

USA TOP09"ophlc Lob, Ft Belvoir, ATTN: ETL-GSL 

USA lntelli9fn« Ctr & Sch, Ft Huochuc.o, ATTN: CTD- MS 

USA lntelligen~ Ctr lo Sch, Ft HuiChua, ATTN: ATS- CTD-MS 

USA Intelligence Ctr lo Sch, Ft HuiChuco, ATTN: A TSI- TE 

USA lntelli9fnce Ctr lo Sch. Ft HuiChuCI, ATTN: ATSI- TEX-GS 

USA lntelli9fnce Ctr lo Sch. Ft Huochuco. ATTN: ATSI-CTS-OR 

USA Intelligence Ctr & Sch, Ft HuiChuCI, ATTN: ATSI- CTO-DT 

USA lntelli9fn~ Ctr 8o Sch, Ft Huochuco, ATTN: ATSI-CTO-CS 

USA lntelli9tnce Ctr 8o Sch, Ft HuiChuCI, ATTN: DAS/SRD 

USA lnt~lligence Ctr & Sch, Ft Huochuc~. ATTN: A TSI-TEM 

USA Intelligence Ctr lo Sch, Ft HuiChuco, ATTN: Library 

1 CDR. HO Ft Huochuc.t, ATTN: Tech Re f Oiv 

2 CDR. USA Electronic Prvg Grd, ATTN: STEEP- MT - S 

1 COR, Project MASSTER, ATTN: Toch Info Center 

Hq MASSTER, USATRADOC, LNO 

R-1<ch Institute, HQ MASSTER, Ft Hood 

USA Recruiti"9 Cmd, Ft S~r on, ATTN: USARCPM- P 

1 Senior Army Adv., USAFAGOD/TAC. Elgin AF Auw Fld No. 9 

1 HO USARPAC, OCSPER, <U'O Sf 96558, ATTN: GPPE- SE 

1 Stimson Lib, Acldemy of Heolth Selene... Ft s.m Houston 

1 Morine CorPI I not., ATTN: Oeen-MCI 

1 HOUSMC, Commtndant, ATTN: Code MTMT 51 

1 HOUSMC, Commtndont, AnN: C".o<le MPI-20 

2 USCG Academy, New LOtadon, ATTN: Admiu ion 

2 USCG ACidtmy, New London, ATTN: Librory 

1 USCG Trolning Ctr, NY. ATTN: CO 

1 USCG Training Ctr, NY. ATTN: Educ Svc Ole 

USCG, Psycho! Res Br, DC, ATTN: GP 1/62 

HO Mod- Ronge Br, MC Ott, Ouonrlco, ATTN: PloS Div 
1 US Mari,. Corps Lt.hlon Ofc, AMC, AJ.undrle. ATTN: AMCGI-F 

1 USATRADOC Ft~.ATTN:ATRO-ED 

I USATRADOC Ft~.ATTN ATPR-AD 

1 USATRAOOC, Ft ~.ATTN: ATTS-£A 

1 USA F-Cmd. Ft Md'hli....,, ATTN: LMnry 

2 USA Aviation Teat ld, Ft Rue:~~«, ATTN: STEIG-fiO 

1 USA A9tY for Aviation Slfety, Ft Ructwr, ATTN: Ubr.-y 

1 USA A9tY for Aviation Slfety, Ft Ructwr, ATTN: Ecluc Adwilor 

~ USA Aviation Sc:h, Ft Ruclwr, ATTN: PO Dr-0 

1 HOUSA Awiadan Svs Cftld, SC Uuil, ATTN: AMIAV-ZDft 

2 USA Awlatlolt ~ ,_. M.. Ectw.dl AFI, ATTN: IAVTI-T 

1 USA Air Oef Sc:h, Ft Ilia, ATTN: ATSA TEM 

1 USA Air Mobility Rtdla Dew Lab, Moffett Flcl, ATTN: SAVDL-AI 

1 USA Aviation Sc:h, Res Tnt Mit. Ft Ruclwr, ATTN: ATST-T-RTM 

1 USA Aviation Sc:h, CO, Ft Ructwr, ATTN: ATST-D-A 

1 HO. DARCOM. AJ.undria, ATTN: AMXCD-TL 

1 HO. DARCOM. AJ.unclria, ATTN: CDR 

1 US Mili18rf Academy, Wen Point. ATTN: Serials Unit 

1 US Mili18rf Academy, W..t Point, ATTN: Ofc of Milt L.drlhp 

1 US Military Acadtmy, W..t Point. ATTN: MADR 

t USA Standardilation Gp, UK, FPO NY, ATTN: MASE-GC 

1 Ole of Naval RICh, Arlington, ATTN: Code 462 

3 Ofc of Naval RICh, Arlington, ATTN: Code 411 

1 Ofc of Naval RICh, ArWngtOn, ATTN: Code 410 

1 Ofc of Naval RICh, Arlington, ATTN: Code 441 

1 Naval ..Wospc Med Res Lab, ro.nuc:oa., ATTN: Acoua Sc:h Diw 

~ Naval ..Wospc Med Res Lab, "-ntacoll, ATTN: Code lit 

1 Naval ..Wospe Med Rts Lab, Pwnucoll, ATTN: Code ll 

1 Chief of NavP•rs, ATTN: Pwn-OR 

1 NAVAIRSTA. Norfolk, ATTN: Satwty Ctr 

1 Nav Dctanographic, DC, ATTN: Code 8211, Charta 6 TKII 

1 Canter of Naval Anal, ATTN: Doc Ctr 

1 NavAirSysCom, ATTN: AIR- 531JC 

1 Nav BuMtd, 1\TTN: 713 

1 NavHellcopterSubSaua 2, FPO SF IIM01 

1 AFHRL IFTI William Af8 

I AFHRL(Tf) LOO\T'f AF8 

t AFHRLIASI WPAF8, OH 

2 AFHAL IDOJZI Brooks AF8 

t AFHRL IDOJNI Uckland AF8 

1 HOUSAF IINYSDI 

t HOUSAF IDPXXAI 

t AFVTG IRDI Randolph AF8 

3 AMRL IHEI WPAF8. OH 

2 AF lnst of T«h. Wf'AF8, OH, ATTN: ENE/Sl 

1 ATC llCPTl.ll Randolph AFB 

I USAF ~rofk(l Lib, 8tooks AF8 ISUL- 4), ATTN: DOC SEC 

t AFOSR INLI, Arlington 

1 AF Log Cmd, McClellan AF8, ATTN: ALCIOf'CRI 

1 Air Force Academy,CO, ATTN: o.ptof Btl Sen 

5 NavPcrs 8o Dew Ctr, San Diego 

2 Navy Med Nluropsydllatric RICh Unit, San Diego 

1 Nrt Electronic Leb, ~Dego, ATTN: Rts Lab 

1 Nav Tr"!J(:en. San Ditcp, ATTN: Code ~L b 

1 NavPostGriSc:h, Monterey, ATTN: Code 55A1 

1 NIWPostGraSch, Monterey, ATTN: Code 2124 

I N..,Tr"''IEquipCtr, Orlando, ATTN: Tech Lib 

I US o.p, of l abor, DC, ATTN: ManPOMt Admin 

1 US o.pt of Juttice, DC, ATTN: Druo Enforce Admin 

1 Nat Bur of Sllndlrdl, DC, ATTN: Cornpuw Info Sectioft 

1 Nat Cle•l"''l Ho...a for MH- Info, Rodtvilll 

1 Oet•v~r federal Ctr, Lalut\vood, ATTN: 8LM 

12 Oeftn• Docu~tation Cant.< 

4 Dlr Psvcn. Army Hq, Ru.eli Ofcs, CanblrTa 

1 Scientific Advsr. Mil 8d, Army HQ. RUMII Ofce, ~e 

1 Mil and Air Att.xhl, Aurtr11n Embetly 

1 Centro: de R~c:he Des Ftcteun. Hurnaine de Ia Dlfln• 

Nationall, Brus:els 

2 C..,adian Joint Staff Washington 

I ClAir Staff, Royal Canadian AF, ATTN: Pwn Std Anallr 

3 Chief, Canadian o.t RICh Staff, ATTN: C/CRDSIWI 

4 Brithtl Del S~f. Brlthtl E~. W..,ington 

-56-

1 Dlf a CMI llllt of EnwiniMedlclne, Clnldl 

1 AIR c:tl-........... ATTN: Info 1¥1. 

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