Technical Pa; 335 LF;

~

1

IMAGE INTERPRETER SCREEPIING

~ 

PERFORMANCE AS AFFECTED BY RESOLUTION,

PRESENTATION RATE, AND SCALE

J. Richard Lepkowski

System Development Corporation

BATTLEFIELD INFORMATION SYSTEMS TECHNICAL AREA

>

0-~

C-

)

c

~

DDC

ft!

~

1ri]

U. S. Army 

~~~i ~~~~~

Research (n~titut

~ 

b r the Rgha~’c)rat and ~

ociaI nccs

September 1978

Approy .d for pubhc relpue . d tnbu~ion unhim~ted. 

.•t.’’- 
a

U. S. ARMY RESEARCH INSTITUTE

FO R T HE BE HAVIORAL A ND SOCIAL SCI ENCES

A Field Operating A gency under t he Jurisdiction of the

Deputy Chief of Staff for Personnel

WILLIAM L. IIAUSER

JOSEPH ZEIDNER Colonel. US Army

Technical Director 1.ommander

Research accomplished unde r contract to

the Departhent of the Army

System Deve lo~~ent Corporati on

NOTICES

DISTRIBUTION Prim.ry distribut ion of th is report hes been made by ARI . Plesie sddress corvespOndSn~

s

concerning diStribution of reports to U. S. Army Rei.arth Itiftittite to, the Behaviorel and Social Sciences. ATTN PERI.P, 5001 Eisenho~

ier Avenue . Alexandria , Virginia 22333

FINAL DISPOSITION: Thus report my be destroyed when it us no longer needed. Please do not return it to

the U. S. Army Research Institute for the Behavioral and Social Sciences.

~~~~~~ The finding. in thus report era not to be construed as an official Department of the Army position .

unless so desugasted by other authorized documents.

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

L
Unclassified

SICURITY CLAUIPICAIION OF THIS PAU (

~~~~ bar. L,.se.~ _____isa A ei~~~I fl A1 R READ WSTRUC1IOISS r5~~rUN I

~~~~~ U LlI I J~ •~~~~ r FlU BEFORE COMPL.ET~~G FO~~ I. ~I.O~ T NUMSER (

~~} — / 2. GOVT ACCLU 1 i.i

~~

I

~~

a ia ‘..~~~ ~~~~~~~~ ~~~~~~~~ -_ )

Technical PaW~ ~ I 

~

2 ~~~~~~~~~~ ~

j i

~~~~~ 

o. ~

t.oa, a .c*s~~~ c0A~ 0 1

~O N R ~~CREENING/EPFORMANCE AS /7

~ 

J~ui ~~68 Jun

~iIND SCALE / ) /. / ~~~ ruai-UT lNq OW~~. WE~~~~~ —

L TL ç~~~ f~WD 318/000/0(1 f .. .

‘-“U- -If J — 

p.

(

~ 

J. Richard/~ePkowsk fl (i~ 

19~~~~~~ ØØ5~ L.

~~~

C. P(~~PO~~~IN0 ORGANIZATION NAME AND ADDRESS 10. PROGRAM £LIMEN.LT. PROJ ECT , YAIS(

System Development Corporation AREA A SORE UNIT NUMURS

5720 Columbia Pike .—~~ 2J620901A72 1 Falls Church , VA 22041 -

II. CONTROL LING OFFICE NAM E AND ADDR(U £&- *,PDWrWu- f Assistant Chief of Staff for Intelligence (77 Sep~~~~~~ ~~ 78 / U.S. Army ‘ .. ,.

. 

~~~~~~~~~~~~~~~ Washington , DC 20310 30

5 4. MONITORING AGENCY NAME A AOOR(SI(Sl ~~U.,.uI fr. CaiIrid tM~ Offle.) II. SECURITY CLASS. (of lAS. i.pon)

U.S. Army Research Institute for the Behavioral Unclassified

and Social Sciences _____________________________

is.. DECLASSIFICAIION/DOSNGRAOING 5001 Eisenhower Avenue , Alexandria, VA 22333 SCHEDULE 

-- IS. DIST RISUTION STAT EMENT (al mS. R.p.rf)

Approved for public release; distribution rnlimited.

17. DISTRISUTION STATEMENT (of IA. ab.I,.ct .if.r.d Sn block 20. If dglf.,.nt froc, ~ .psxf)

Is. SUPPLEMENTARY NOTES

IC. HEY WORDS (Caith.u. an ,.ww.. aid. If .rec...a ~

. aid identify by black niasb.t)

Photographic imagery Resolution Film movement rate

Near real—time Scale Display size

Simulated telemetered displays Optical magnification Viewing area

Image interpreters Transmission bandwidth Viewing time

Screening accuracy Smallest resolvable ground dimension

~O. ASITRACT (C.Wffius evwee .5* If isee..wy aid ld.ntSty by block eu A.r)

This study measured performance levels of image interpreters , using

both direct viewing and viewing with magnification , to screen 70mm photographic imagery moving at six different rates and varying in scale and

resolution . The resolution of the imagery was varied to simulate imagery

obtained with differen t transmission bandwidths. The results were as

follows.

(continued)

DO ,

~~ 1473 £O,TSON OF t NOV UIS OSIOLETI Unclassified

SECURItY CLAS$SFICATIOW OF 1555$ PAGE fiNren D a gnM..d)

~~ 

r a e?

~~~~ 

f ~ 

c

~~

co /

.

~ 
~ - .- --- - -.: . .

Unclassified

SECURITY CLAU$PICATION OF THIS PA0E(W~a bar. &,Sare

~

20.. Abstract (cont)

- ‘.1. There is little loss in screening accuracy at any level of

resolution and/or magnification for frame presentation rates of 6.0

to 1.5 sec/frame with the 1:2,000 scale imagery and 6.0 to 2.0

sec/ frame for the 1:4,000 scale imagery .

2. In general, the poorer the image resolution , the lower the

screening accuracy.

3. For constant display format and image resolution , screening

accuracy is significantly greater for the larger scale display .

4. Two—power optical magnification of the photographic imagery

resulted in a decrease in screening accuracy . Increasing viewing time

for magnified imagery by a factor of four so that the incremental area

viewed per second was equated for direct and magnified viewing resulted

in no significant difference between the two viewing conditions .

Tradeoffs are possible between and among the factors of scale,

presentation rate, and resolution .

~~~~

ktI SsctIsS 0

fl*SSOUPC!I 0

J1iS1IHUIISt.

~~~~~— 

. 

Unclassified

SECURITY CLAUIFICATION OF THIS PAOE(IThen DOS a Int.r.d)

____ ~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~ 

. 

.

~~~~ .
~

Technical Paper 335

IMAGE INTERPRETER SCREENING

PERFORMANCE AS AFFECTED BY RESOLUTION,

PRESENTATION RATE, AND SCALE

J. Richard Lepkowski

System Development Corporation

BATTLEFIELD IN FORMATION SYSTEMS TECHNICAL AREA

Submitted as complete and Approved By: technically accurate , by:

Edgar N. Johnson A.H. BlrnbaUm. Acting Director

teChniCal Ari Chief ORGANIZATIONS AND SYSTEMS

RESEARCH LABORATORY

Joseph Zeidner

TECHNICAL DIRECTOR

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

September 1978

Army Project Number Image Interpretation Displays

2J620901A721 Cont ract DAHC194T.C-0050

Approsed I o public raissss~ 

distribution unlimited.

______________________________ - .
~~~~~~~~~~ -

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 military

agencies by briefing or Disposition Form.

J 

______

______
FOREWORD

The Battlefield Information Systems Technical Area of the Army Research Institute (ARI ) is concerned with the human resource demands of

increasingly complex battlefield systems used to acquire , transmit, process , disseminate , and utilize information . This increased complexity

places greater demands upon the operator interacting with the machine

system . Research in this area focuses on human performance problems

related to interactions within command and control centers as well as

issues of system development. Research subjects include software development, topographic products and procedures , tactical symbology , user—

oriented systems, information management, staff operations and procedures , decision support, and sensor systems integration and utilization.

One increasingly important source of intelligence information on

the modern battlef ield is teleme tered imagery from remotely piloted

vehicles or other sensor platforms . A first step in real- or near realtime exploitation of this information involyes screening the many images

obtained , so that the limited number of available interpreters can produce timely intelligence. Output of information systems is strongly

affected by the interaction of design specifications and human capabilities. Telemetered imagery imposes high demands upon already overloaded

tactical communications . One potential solution to this problem is to

use low-resolution imagery transmitted by narrow radio bandwidths . Previous ARI research (Technical Paper 213) has found that low-resolution

imagery can be used for rapid screening . The present research extended

earlier findings , using imagery of known resolution to recommend system

design tradeoffs and provide performance data .

Research in the area of sensor systems in tegra tion and util iza tion

is conducted as an in-house effort augmented by contracts with organizations selected for their specialized capabilities and unique facilities .

The research presented here was conduc ted by personnel from the Sys tem

Development Corporation under the program direction of Dr. Abraham H.

Birnbaum . Research in this area was responsive to general requirements

of Army Project 2J620901A721 and to special requirements of the U.S.

Army Assistant Chief of Staff for Intelligence.

._J

~

t. t€L~&%

OSE N ID R

nical Director

L

- 

___ ___i . 

—--- .

— -—---- -- 

-
IMAGE INTERP RETER SCREENING PERFORMANCE AS AFFECTED BY RESOLUTION ,

PRESENTATION RATE , AND SCALE

BRIEF

Requirement:

To determine the performance levels of image interpreters, using

direct viewing and viewing with magnification to screen moving photographic imagery varying in scale and resolution. The variation in resolution simulates imagery obtained under different transmission bandwidths .

Procedure:

Forty—eight image interpreters were randomly assigned to screen four

sets of 100—frame rolls containing 1:2,000 and 1:4,000 scale 70mm imagery

at one of six film—movement rates under viewing conditions of no magnification and 2-power magnification . Each 100—frame roll contained essentially the same 50 target and 50 nontarget frames ; the sequence of target/nontarget frames was randomly determined . Scene content from frame

to frame was neither overlapping nor contiguous . For each roll of imagery ,

the 100 frames were divided into four batches——25 frames per batch-—with

each batch at one of four levels of resolution : 8, 12 , 16 , and 24 inches

smallest resolvable ground dimension . The resolutions were systematically

varied for the four rolls of imagery , so that a subject never viewed a

given scene twice at the same resolution.

Two 70mm projectors were modified to permit direct viewing of the

imagery . One device , using specially prepared practice imagery, was

used for training the examinees to respond at the proper time . Subjects

had to indicate which frames contained targets (wheeled or tracked vehicles) and which did not. The other device was used for the experimental runs. Subjects made their responses by actuating a three-p’~sition

swi tch , which was wired to a polygraph event recorder . The response

tapes were scored for screening accuracy and screening thoroughness.

Findings:

lnterpr~ tation of moving 70mm positive photographic imagery for

identification of wheeled or tracked vehicles became significantly less

accurate with poorer image resolution , faster presentation rates, and

reductions in image scale .

In general , the poorer the resolution , the lower the screening accuracy scores.
_ _ __ ___ -

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

--

There was little loss in accuracy generally with presentation rates

of 6.0-1.5 seconds per frame for large—scale imagery and 6.0-2.0 seconds

per frame for small—scale imagery at all levels of resolution . At faster

rates than these, accuracy decreased as rates increased.

Accuracy scores were higher with larger scale imagery (1:2,000, in

which the display showed a smaller area of terrain) than with smallscale imagery of the same resolution.

Doubling the size of the image by 2x magnification without changing

resolution or scale did not increase accuracy . Unless viewing time was

lengthened proportionally (4x) to the increased perceived viewing area,

accuracy decreased.

Utilization of Findings :

The factors of image resolution , presentation rate, and scale are

of primary importance in determining screening accuracy for 70mm telemetered image displays for wheeled or tracked vehicles.

Tradeoffs which may be acceptable operationally are possible among

these factors. For example, screening accuracy of poor resolution displays can be enhanced by lengthening presentation rate by .8-2.0 seconds

per frame. Increasing viewing time more than 2.0 seconds per frame does

not increase screening accuracy . Accuracy is also improved by increasing

the scale of the ground station display so that the imagery covers a

proportionately smaller area of terrain, even though the smallest resolvable ground dimension is unchanged .

F-
IMAGE INTERPRETER SCREEN ING PERFORMANCE AS AFFECTED BY RESOLUTION ,

PRESENTATION RATE , AND SCALE

CONTENTS

Pag e

BACKGROUND 1

OBJECTIVES 1

PROCEDU RE 2

Experimental Sample 2

Research Design 2

Experimental Materials 3

Technique Used to Motivate Subjects 6

Pretest Training 6

Experimental T~ sting 7

Scoring 7

RESULTS 8

Screen ing Accuracy 8

Screening Thoroughness 16

SUMMARY AND IMPLICATIONS OF FINDINGS 17

Image Resolution 18

Presentation Rate 18

Image Scale 18

APPENDIX A . Techr.ique Used to Produce Imagery 19

B. General Background 23

C. Training Instructions 25

D. Experimental Run Instructions 27

DISTRIBUTION 29

LIST OF TABLES

Table 1. Testing schedule for the six different

presentation rates 5
LIST OF TABLES (con tinued)

Table 2. Analysis of variance of screening accuracy

scores for the indicated variables and

interactions 8

3. Screening accuracy means for the indicated

~

.econds per frame 9

4. Screening accuracy means for large scale ,

small scale , and both scales under

magn ification 9

5. Screening accuracy means for the smallest

resolvable ground dimensions of 8 inches ,

12 inches , 16 inches , and 24 inches 10

6. Comparison of mean accuracy scores for

small-scale unmagnified (5) and smallscale magn ified (SM ) imagery , when viewing

time per unit area of format is constant 15

7. Comparison of mean accuracy scores for

large-scale unmagnified (L) and largescale magnified (LM) imagery, when viewing

time per unit area of format is constant 16

8. The mean screening thoroughness scores for

each set of cond itions of scale , smallest

resolvable ground dimension (SRGD) , and

ra te (in sec/frame) 17

A-l. Selected groups and elements for the enlarged

Mili tary Standard lO5A Resolution Chart and

thei r representative ground dimen sions 22

LIST OF FIGURES

Figure 1. The average screening accuracy scores for each

condition of film movement rate and level

of resolution for SMALL-SCALE imagery with

the task restricted to detection of wheeled

or tracked veh icles 11

2. T

~

ie average screening accuracy scores for each

condition of film movement rate and level

of resolution for LARGE-SCALE imagery with

the task restricted to detection of wheeled

or tracked vehicles 12 -

~~~~ .~~~~~~ ___
LIST OF FIGURES (continued)

Figure 3. The average screening accuracy scores for

each condi tion of film movement ra te and

level of resolution for SMALL-SCALE MAGNIFIED

imagery with the task restricted to detection

of wheeled or tracked veh icles 13

4. The average screening accuracy scores for

each condi tion of film movemen t ra te and

level of resolution for LARGE-SCALE MAGNIFIED

imagery with the task restricted to detection

of wheeled or tracked vehicles 14

.1
IMAGE INTERPRETER SCREENI~ PERFORMANCE AS AFFECTED BY

RESOLUTION , PRESENTATION RATE , AND SCALE

BACKGROUND

The resolution of transmitted imagery depends upon the size of the

radio bandwidth used to transmit the imagery . For a constant transmission time , bandwidth required is directly proportional to the square of

the resolution needed . When near real-time interpretation at a ground

facility is desired , the imposition of the demands of high-quality imagery transmission on an already crowded radio band can prove troublesome. To allow transmission of high-quality imagery as fast as possible,

all the ava ilable bandwidths may have to be used , to the detriment of

other kinds of radio communications designed to operate within those

frequencies . One solution to this problem may be initial use of lowresolution imagery (transmitted at narrow bandwidth) , which can be

screened rapidly followed by retransmission, at higher resolution , of

frames selected as containina targets .

The author has undertaken previous work to investigate the potuntial of rapid screening of low-resolution imagery. A pilot study revealed that moderate success in screening fair-quality moving imagery

can be attained with 70mm film movement rates up to 3 in./sec. (or

about .8 sec/frame) if the scale is not too small. These results provided guidance for selection of film movement rates used in a second

experiment. The second experiment investigated the effects of six

film rates (.8, 1.0, 1.5 , 2.0, 4.0, and 6.0 sec/frame) , f our levels of

relative resolution , and two levels of scale (1:2 ,000 and 1:4,000) upon

success of screening 7Onun imagery for wheeled or tracked vehicles .1

Unfortunately, in the second experiment the precise resolution of the

imagery in terms of smallest resolvable ground dimension at each resolution level was unknown ; therefore the present experiment was necessary .

OBJECTIVES

This study was undertaken to assess the feasibility of using lowresolution imagery for rapid screening . The independent variables used

were the same as those previously described for the second experiment,

but the results of this experiment are more definitive because the

smallest resolvable ground dimensions were known for the different

• 1

Lepkowski, J. R. Study of Near Real—Time Screening Performance. 1:

• Scale , Resolution , and Presentation Rate . ARI Technical Research Note

213 , August 1969. (AD 698455)

1

L • •~~~~~~~~~~~~~~~~~~~~~~~~~~~ • ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~• ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

-

•

~~~~
- • - • -- •• - • •• - •- - - •- 

resolution levels. In addition , in this experiment each scale was

viewed under 2-power (2x) magnification to obtain measures of the effect of magnification on screening performance .

In summary , the objectives of this study were to determine the effects of level of resolution , movement rates , scale, and magnification

on image interpreter performance in screening 70mm imagery for wheeled

or tracked vehicles .

PROCEDURE

Experimental Sample

Forty-eight enlisted men who recently graduated from the Image Interpretation Course at the U.S. Army Intelligence School at Fort Rolabird ,

Md ., participated in the study as examinees . These men were members of

four successive graduation classes during January and February 1969. Half

were between 19 and 20 years of age, and the rest were between 20 years,

1 month , and 26 years , 8 months .

Research Design

The task in this study was to screen each frame for wheeled or

tracked vehicles. Each frame required a “target” or “nontarget” response. The presence of at least one vehicle was sufficient to classify

a frame as a target frame.

The experimental design permitted all combinations of the three independent variables of interest to be’tested. The independent variables

were

1. Scale in four levels : 1:2,000, 1:4,000 viewed with no magnification and at 2x magnification ;

2. Film movement rate in six levels : 6.0, 4.0, 2.0, 1.5, 1.0, and

.8 sec/frame ; and

3. Imagery resolution in four levels at each scale level: where

the smallest resolvable ground dimensions (SRGD) are approximately 8, 12 , 16, and 24 inches each .

The dependent variables were

1. Screening accuracy and

2. Screening thoroughness .

2

• - •. - • 

-•---- --. -—-~

-•------•-

----I-- - - - . - ---- ---- -
F -- -- - -

~~~~

- -

~~~

-

~~~ 

- - ---- - - - • -- - -- -

~~~~~

-—

~~~~~~

-----

~~

- 

~~~

• -—---

~~~~~~~~~~

Screening accuracy was defined as the sum of frames correctly classified

as target frames and nontarget frames. In terms of the following diagram , screening accuracy = A + D.

Stimulus frame

Target Nontarget

A B

Target

Correct Incorrect

Response

C D

Nontarget

Incorrect Correct

Screening accuracy = A + D.

Screening thoroughness was defined as the number of frames responded to,

of the 100 frames presented in each run; in terms of the diagram,

• Screening thoroughness = A + B + C + D.

Experimental Materials

Imagery. The imagery used in this study met the following criteria.

1. Target types used--wheeled and/or tracked vehicles (trucks,

trailers, tanks, automobiles, bulldozers , cranes, road graders,

front—end loaders, armored personnel carriers, and a universal

tractor);

2. A range of target densities per frame (zero to about a dozen);

3. A wide range of foliage cover (0% to about 90%);

4. Enough imagery to provide 50 target frames and 50 nontarget

frames in 70mm format;

5. Scales about 1:2,000 and 1:4,000;

6. Absence of manmade objects other than vehicles and roads; and

7. Resolution, the smallest resolvable ground dimension (SRGD),

of the imagery--must be known and be relatively consistent at

the selected levels.

3

~~~~~ lIL~~~~~ - --- — - •~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ •
-~~~~~~~~ ~~

- ---- -----

The procedure used to produce the imagery meeting the above criteria is described in Appendix A. This procedure was used to produce

eight sets of frames that were almost identical in target content and

format size but differed in scale (i.e., scale 1:2 ,000 and 1:4,000) and

resolution (SRGD ’s of 8, 12 , 16, and 24 inches). Due to the constant

format size , each large—scale frame displayed only one-quarter of the

terrain covered by the equivalent small—scale frame.

So that all examinees could contribute to the screening accuracy

scores for all levels of resolution and scale , the eight sets of imagery

were cut into batches containing 25 frames . The batches were respliced

together into eight sets of imagery, so that each set was at one scale

and contained all levels of resolution . For example , in a given set the

first 25 frames might be the highest resolution , the second 25 frames the

third-highest resolution, the next 25 frames the second-highest resolution , and the last 25 frames the lowest resolution .

The testing schedule shown in Table 1 was replicated for each of

the six film movement rates, eight subjects being used in each of the

six replications . Each subject viewed four sets of 100 frames, each

set differing in the combination of scale and magnification but containing essentially the same imagery . The capital letters in the body

of Table 1 represent the display scale for each set of 100 frames :

small (S), small-magnified (SM), large (L ), and large-magnified (LM) .

The order in which the different scales were used is indicated in

Table 1 by the order of the capital letters from left to right. Within each set of 100 frames , the 25 frame batches for each resolution are

represented in the body of Table 1 by the lowercase letters a, b , c,

and d. Highest resolution is indicated by a, and lowest resolution

by d. The serial order in which the different resolutions appeared

within a set of 100 frames is indicated by the order of the lowercase

letters. The resolutions were systematically varied for the four rolls

of imagery so that a subject never viewed a given scene twice at the same

resolution. Thus, exaininees 1 and 2 were presented with the different

scales in the sequence S , L, SM , and LM . Wi thin the set of 100 frames

for the f irst scale , S, the order of presentation for resolution was

a, c , b , d.

Testing and Recording Devices. Two similar sets of display apparatus were employed in the present experiment . Each piece of equipment

consisted of a 70mm film projector and a motorized film drive permitting

selection of film movement rates ranging from barely perceptible motion

to about 3 in./sec. During this study, repeatability of a given ra te

was obtained with a maximum error of 2%. Oversized reel hubs reduced

film movement rate difference between the first 10 and the last 10 of

the total 100 frames in each run to less than 1%. Runs at a given movemerit rate varied by a inaximun of 2% from the specified movement rate .

4 

. 

—~-- - - -•— -•- - - - • - -

~ •-~~~~- -

.

- -•
—----- -.— --.—-——-———— *--—.—.—..————— --•--—--.—----------

Table 1

Testing Schedule for the Six Different Presentation Rates

Scale and resolution

l and 2 S L SM 124

acbd cbda dacb bdac

“4

3 and 4 L S 124 SM

bdac dacb cbda acbd

0 S and 6 124 SM L S

dacb bdac acbd cbda “4

~ l and 8 SM 124 5 L

cbda acbd bdac dacb

The optics were removed from each projector to permit direct viewing of the imagery . Light diffusers were placed between the light source

and the film to prevent “hot spots” and to spread the lighting more evenly. The illumination intensity control for each piece of equipment was

set to provide approximately 2.45 foot lamberts of backlighting . This

light level was the average level preferred by three experienced image

interpreters who were free to vary the light intensi ty while viewing

similar moving imagery in a preliminary study .

For both the unmagnified , small-scale and unmagnified , large-scale

runs, the projectors were so placed that the examinee could select his

own viewing distance . All examinees selected a position between 12 and

15 inches from the imagery . For the magnified-scale runs , the viewing

distance had to be fixed at 17.25 inches from the optical center (or

principal plane) of the 5-inch diameter , double-convex , 2-power lens to

obtain a 2x magnification of the imagery . A mount with padded headrest

was attached to the testing equipment to maintain the appropriate viewing

distance .

A paper tape record of examinee responses on the experimental run

was obtained by use of a polygraph event recorder. One channel of the

polygraph indicated the beginning and end of each frame’s presentation

period. A second channel gave an indication of those frames selected

as containing targets and a third channel , those frames not containing

targets . Examinees were required to indicate their selection for each

frame by actuating a spring-loaded , three-position switch . Flicking the

switch to the right indicated that the frame being presented was

5

k 
-

~~~~~~ -----~~~~~ -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~ •

selected as containing one or more targets. Flicking the switch to the

left indicated that the frame being presented was selected as containing

no targets. Exaininees used the middle or neutral position for the waiting

period between responses.

Technique Used to Motivate Subjects

The examinees were tested in pairs. Each pair was asked to read a

one-page “General Background ” sheet (see Appendix B), which introduced

the matter of radio transmission of photographic imagery and told the

subjects what was expected to be learned from the experiment . A discussion period of several minutes followed , to further explain photographic

transmission problems and to interest the examinees in the importance of

obtaining the desired data . The experimental design was then explained

in some detail to show how each pair was assigned to the various sets of

conditions but without revealing the set of conditions to which the pair

was assigned .

Pretest Training

Since an early or late response to a given frame during the experimental run would be associated by the recorder with the preceding frame

or following frame , respectively, instead of the frame intended , some

pretest training was needed . One of the two. available display apparatus

was used as a training machine . A special set of imagery was prepared

containing eight target frames (with vehicles which were easily seen)

and seven nontarget frames (without vehicles or man-made objects) .

At the training machine , each pair of examinees was given instructions in how they were to respond to each frame of imagery . A copy of

the Training Instructions appears in Appendix C.

The exaiuinees were assured that if they did not readily see a target on a given frame , that frame was a nontarget frame. The object of

this pretest training was not to check the ability of an examinee to

detect targets, but rather to teach him when to respond .

Filn. movement was from right to left. The examinee was told not to

respond to a frame until some part of that frame was behind the left edge

of the viewing port, which was marked with green .

The margin of the pretest imagery was punch-coded for a pickup

switch .

2 The on/off status of this pickup switch was used in conjunction with the position of the Target/No Target switch to produce a red

2

With the codir~q scheme employed, it was also necessary to introduce some

blank frames in the run to confuse the examinee concerning the sequence

of frames.

6

‘S 

~~~~~~~~~~~~~~~~ •_
light directly below the imagery in the viewing port whenever the correct response was early or late or a misinterpretation occurred . Misinterpretations were rare , and when they did occur , the examinee typically

remarked that he recognized making that type of error , or had moved the

Target/No Target switch in the wrong direction .

Each examinee was trained with the film movement rate he was scheduled to receive on the experimental machine . Training was accomplished

rather quickly where the 4 and 6 sec/frame rates were scheduled . But

for the faster rates , especially the .8 sec/frame rate——which required

decision/reaction times approaching the psychophysiological limit--sev-3 eral trials, first at slow and then at increasing speeds, were allowed .

All examinees were required to give at least two error-free runs at

their scheduled rates on the training machine before proceeding with

the experimental run.

Experimental Testing

After the training session , each examinee, in turn, was seated at

the experimental run machine and given instructions for the experimental

testing (Appendix D). The examinee was informed that he was to screen

100 frames of imagery for vehicles (tanks , trucks, trailers , and automobiles, as well as the various types of engineer corps equipment) and

reminded of how and when to respond to each frame . He was also informed

that there would be no blank frames and no red light to indicate early

or late responses . In addition , the examinee was informed that he could

expect to see the image quality change periodically.

Scorin~

Scoring keys were made for each of the six film movement rates. To

nake the keys , a tes t set of imagery was allowed to run through the

machine with the frame counter on at each of the six speeds. Since the

polygraph ran at the constant rate of 3mm/sec , paper strips of six different lengths were obtained . The target frames were then noted on each

strip by colored pencil marks between the proper ink tic marks which delineated the beginning (and end) of each frame . It was a relatively

simple matter to score each run against the appropriate scoring key .

3

Reaction times to discrete stimuli have been reported in the literature

as ranging in values from .23 to .50 second . If one includes other delay times such as latency (at least .1 second) and perceptual span of

vision (on the order of .2 second) it appears that a screening rate of

.8 sec/frame for 70mm imagery is very close to, and may in some individuals exceed , the psychophysiological limit of response time

.7
-

~~~~~~~~~~~

RESULTS

S reening Accuracy

The results of the complete analysis of variance of screening accuracy appear in Table 2. For this analysis of variance , which is based on

a large number of degrees of freedom and several variables , the .01 level

of significance was adopted as the minimum criterion , to reduce the risk

of accepting a difference as being significant when in fact it might not

be significant. All F values in Table 2 (except for order , rate x order

interaction, triple interaction , and residual error term) are significant

beyond the .01 level.

Table 2

Analysis of Variance of Screening Accuracy Scores

for the Indicated Variables and Interactions

Source of

variation df MS F P

Rate 5 102.6138 9.1265 .001

Order 3 14.1055 1.2545 —-

Rate x order 15 8.0805 .7187 --

e

1 24 11.2435

Scale 3 449.4319 189.7538 .001

Resolution 3 121.2826 51.2065 .001

Set position 3 22.6784 9.5750 .001

Batch position 3 239.15Ot 100.9713 .001

Scale x resolution 9 26.3520 11.1260 .001

Rate x scale 15 5.4152 2.2863 .01

Rate x resolution 15 5.3534 2.2602 .01

Rate x period 15 5.5117 2.3271 .01

Rate x batch 15 5.5881 2.3593 .01

Rate x scale x resolution 45 4.1853 1.7671 .05

Residual 234 4.1960 1.7716 .05

360 2.3685

Total 767

8 

______ 

• 

“

~~~~~~~~

---

~

- -

~~~~~~~

--- 

~~~~~~~~~

-- -
The screening accuracy means for rates are shown in Table 3. The

dashed underlining in Table 3 indicates those means, as determined by

the Newman-Keuls Test, that could have been drawn from a c~~w~

on population of means at the .01 level of confidence . In the initial analysis ,

the .8 sec/frame rate shows a significantly poorer performance than the

other ra tes . However , further analysis shows that the 1.0 and .8 sec/

frame rates are not statistically dissimilar at the .01 level of confidence , thereby indicating the marginal status of the 1.0 sec/frame rate

performance score .

Table 3

Screening Accuracy Means for the Indicated Seconds Per Frame

Sec/frame 4.0 6.0 2.0 1.5 1.0 .8

72.68 72.52 71.24 70.08 66.88 63.64

Note . Dashed underlines group items not significantly different from

each other.

The screening accuracy means for scales are presented in Table 4.

The Newman-Keuls Test has shown that each of the means in Table 4 is

significantly different from the other means . With both large and small

scales, direct viewing of moving imagery for screening purposes is shown

to be superior to screening the same moving imagery under 2x magnification.

Table 4

Screening Accuracy Means for Large Scale , Small Scale ,

and Both Scales tinder Magnification

L LM S SM

76 .96 71.64 66.52 62.92

9

I

L ___________________
r

Table 5 presents the means of screening accuracy scores for the

four levels of resolution. According to the Newman-Xeuls Test , the

means in Table S are significantly different from each other except

those for resolution levels of 16 inches and 24 inches SRGD. The mean

screening accuracy scores for the 16-inch and 24—inch SRGD levels are

less than a point apart, and both show significantly poorer screening

performance than the two higher levels of resolution . The 8-inch SRGD

level is significantly higher than the 12-inch SRGD level .

Table 5

Screening Accuracy Means for the Smallest Resolvable

Ground. Dimensions of 8 Inches, 12 Inches,

16 Inches, and 24 Inches

8 inches 12 inches 16 inches 24 inches

73.84 69.92 67.32 66.92

Note. Dashed underline groups items not significantly different from

each other.

Figures 1 through 4 (one for each~ sca1e level) were constructed to

illustrate the screening accuracy mean score trends for the several levels

of resolution and film movement rate . In these figures, two horizontal

lines are added . The lower line shows the chance performance level (50

correc t classifications out of the 100 frames classified) that would be

expected if the interpreter guessed concerning the target/nontarget nature

of each successive frame . The upper line shows the 1% fiducial limit,

61.65 correct classifications per 100 frames . On the average , one interpreter out of 100 interpreters could be expected to obtain a screening

accuracy level of 61.5 correct classifications or higher , assuming that

all interpreters classified all frames strictly by guessing .

Figures 1 through 4 show that, with some minor fluctuation, there

is li ttle loss in screening accuracy scores for a presentation rate of

6.0 to 1.5 sec/frame for large scale and from 6.0 to 2.0 sec/frame for

small—scale imagery at all levels of resolution . For all but the highest

resolution, performance was better with 1:2,000 scale than with the

1:4,000 scale imagery .

10

H
I

~~~~~

\L

- . 0 I

U

\

~~ 11

\~ -j w U, 0 5

-& U, u. -J

z

o U, >. o 0 5 — 

U. _J P .- a o o It U C) ~ U, U, U,

U

- o

~~~~ J 

. — w o o

~J ~~ C) .c

.2 woo .0

~

44J

$4

E ’ O O

-4

U

$4

—4

2 $

3WO~ € AYV~ fl30V ~~N*Ø33~~Zm

11

-
~ 

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

_ ____

____________ -4 — — U

o

‘0 U S

(1 Q

~~ 

n p ~0 3 S

P \I

jJ

~~~.OO

-

~

—I

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ‘us4)

~

1.J C)

o ~i

$4 04.’ O c t —4 0

o

Ott

o w — 04.) 40t0 .00

-S U, ~

)

IJJ S .0 > 0 ‘ $4~~J U, ~~ 0 ... -j U. ~

-, U,

U ~j U,

— z 0. 0

U

2 5

w-

)

I

) U,

44

U I

o

. 4..

•-4 j.

~ U) O w O t

~~-4 woo

o .

~~

0 > 5

• 0 W OO

$4

~~~0 0

C.,,

3V030 A~ Y~ fl3

~ Y 9pd,U3aw ~ 0

12

‘S
_________________________________ ____________ 14.1

— —— S o

- S O c — 4 0 •

e V 0 ‘ 0 0 f 5 0

-I.’ \

~~~ 

-J 0 U

~ 4 4 0

j

~

<

~

.oo

.‘ 0 4 4

U C,’ S W —

-.4

U)

‘1.1 5 04)

O W

0.0

-.4 4.’ 4.’ o ‘0 4.’ O -‘-4 o~~~ — 0 I’)0 .04 -1

5 0 0

Ui

-S WI,’ Ui 0 U. S

-S Ui

-S () CU Z 0) 4-I — .( z w c ~

. I o 0 0 O Z — U, 00

— U4 U,

It

O W

I

.

-

~~u w O U~ —4 040

o

c.,j 0,

~~~~ O O x > ‘.4 CI) O ‘0

L

W 44 0

O O . 4 44 ~ ‘

u C) V 0 0

0 4 . ’ O -.4 $4

3~ O3S ADVWfl 3DV 5NN403V~~

13

- -

~~~------ 

~~~~~ 

_ _ ._i ___ __ _ _ _ _

_

•_ _ ‘

=_i__ ____
— -‘-- — --—-— —- _ --------- —- _ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ----—------‘-—- -- ---—~

-—-~~------- _

0 0 —

o s o

- 4 0 f_I 

~~~~ ‘ -.4

‘J LJ~~ J .

° ‘0 1.)

III 0 0

[0W

4.1 0 0 S W

~~ o w U 0) ‘-4 0 4 0 (0 CU -.4

4.. 0.0 O~~~~~W O~~~ > .-4 I-)

0 ‘0 0440 ) O o .k.: . IL~ 44144 0 0 ‘0 W O O 0 4 ) 0 --4 44

o

W 0 ’ 0 >U, W 0 0 . 4

441) O 0)

El 0

~~~

0

44

0

-.4~

____________________ ________ ______ 

C.

2

~H0~ S A Z~VH(1D0V 9NINW3~~35

14

_____________________ -

~-- - ---
Scores for magnified and unmagnified imagery we re also compared

when the viewing times per unit area of forma t were the same . Format

and target image size appear twice as large in each dimension when viewed

under 2x magnification and therefore they seem to be moving more rapidly

past the viewer. Consequently , the scores for the unmagnified imagery

were compared with magnified imagery having film movement rates four

times slower .

Of the six rates used in the study, only four could be used in the

comparisons . These were , for each scale : 1.5 sec/frame for unmagnified

imagery versus 6.0 sec/frame for magnified image, and 1.0 sec/frame unmagnified versus 4.0 sec/frame magnified .

Magnification of the small—scale imagery offered no significant improvement in screening performance , even though four times the amoun t of

time was allowed to do the task (see Table 6). Each of the means in

Table 6 is based on the scores of the examinees that were tested with

the given film movement rate . The standard error of the difference between the means is based on an error term obtained through an analysis

of variance of the four means .

Table 6

Comparison of Mean Accuracy Scores for Small—Scale

Unmagnified (S) and Small-Scale Magnified (SM)

Imagery , When Viewing Time Per Unit Area of

Format is Constant

Film movement

rates S SM t P

1.5 vs. 6.0 66.36 67.00 .232 ——

1.0 vs. 4.0 62.00 65.64 1.319 --

The same kinds of comparisons were made with the large-scale imagery .

The mean accuracy scores are shown in Table 7.

15 
Table 7

Comparison of Mean Accuracy Scores for Large-Scale Unmagnifi’?d IL)

and Large-Scale Magnified (LM ) Imagery , When Viewing

Time Per Unit Area of Format is Constant

Film movement

rates L LM t p

1.5 vs. 6.0 80.24 72.64 2.61 .05

1.0 vs. 4.0 73.64 76.24 .89 --

The data in Table 7 indicate that magnification of large-scale imagery provided no improvement in screening performance, even though four

times the amount of time was allowed to do the task . In fact, viewing

the large—scale imagery at 1.5 sec/frame resulted in significantly better

performance than viewing the magnified imagery at 6.0 sec/frame .

Screening Thoroughness

The ratio of the number of frames responded to, either correctly or

incorrectly , over the total number of frames presented constitutes an

individual ’s screening thoroughness score . The average screening thoroughness scores of the eight examinees tested under the conditions of

scale , resolution, and film movement rates are given in Table 8.

Review of Table 8 reveals that the screening thoroughness scores

all approach or achieve 100%. Because of this homogeneity , a rigorous

statistical analysis of the data was not attempted .

16

L

I 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -----~~ ~~ - -- .

~~~
~ 

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

Table 8

The Mean Screening Thoroughness Scores for Each Set of

Conditions of Scale , Smallest Resolvable Ground

Dimension (SI~3D), and Rate (in sec/frame)

Large scale Small scale

SRGD 8’ 12” 16” 24” 8” 12” 16” 24”

6.0 100 100 97 100 100 100 99.5 100

4.0 99 100 100 100 100 99.5 99.5 100

F 2.0 100 100 100 100 100 100 100 100

1.5 100 99.5 100 100 100 100 99 100

1.0 100 98.5 100 98.5 98.5 99.5 99 98.5

.8 99.5 100 100 100 98.5 100 100 99.5

Large scale, magnified Small scale , magnified

8” 12” 16” 24” 8” 12” 16” 24”

6.0 99 100 100 100 100 99.5 100 lciO

4.0 100 99.5 100 100 100 99 100 99.5

2.0 100 100 100 99.5 99.5 99.5 100 100

1.5 100 98.5 100 99.5 98.5 100 100 99.5

1.0 98.5 99.5 96 100 100 98.5 99.5 100

.8 99 100 100 99 97.5 99.5 99 98.5

SUMMARY AND IMPLICATION S OF FINDINGS

The three factors of image resolution, presentation rate, and image

scale affected image interpreter screening accuracy of 7onsn imagery rolls

whose successive frames contained nonoverlapping and noncontiguous terrain, for wheeled or tracked vehicles . Tradeoffs which may be acceptable

operationally are possible among these factors .

17

L 

~~~~~~~~~~~~~~~ ~~~~ -.
—-- -.--- ~~- -“-- --“- - - -~~~----- ---—-“- - -

~~~~~—- .—-- ---

Image Resolution

Imagery resolution level (smallest resolvable ground dimension, or

SRGD) is important because use of lower resolution levels resulted in

poorer screening performance .

Presentation Rate

For the type of imagery and task used in this study , within the

range of .8—2.0 second viewing time per frame , poor resolution can be

compensated for by increasing viewing time per frame. Increasing viewing time per frame beyond 2.0 seconds does not increase screening

accuracy .

Image Scale

Increasing the scale of the imagery increased screening accuracy .

Wi th a constant display format, in which larger scale imagery covers a

proportionately smaller area of terrain, screening accuracy scores were

higher when large—scale imagery (1 :2,000) was used than when small-scale

imagery (1:4,000) of approximately the same resolution was used . This

increase in accuracy could be due to displacement of targets toward

the center of the display , to elimination of nontarget content from the

display, to increased size of targets and nontarget “noise ,” or to some

combination of these factors .

However , doubling the size of the imagery by 2x optical magnification , which increases perceived viewing area without changing resolution

or scale , caused a decrease in screening accuracy when viewing times remained the same . When viewing time was increased fourfold to compensate

f:r the increased viewing area, accuracy was the same for magnified and

unmagnified imagery.

18 

__ _ i__ ,

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

~~~~-,
APPENDIX A

TECHNIQUE USED TO PRODUCE IMAGERY

An extensive search of film libraries maintained by the Army, Navy,

and Air Force proved fruitless in that not enough imagery could be found

that met all of the criteria for imagery to be used in this study . The

most difficult criterion to meet was one calling for imagery with known

and consistent resolution. Therefore, it was decided to acquire the

imagery first-hand .

With the cooperation of the Commanding Officer , U.S.M .C. Air Station ,

Quantico, Va., a twin engine C-45 equipped with camera mounts was made

available to ARI personnel. Marine Naval Aviators, aerial photographers ,

and a CA-B, 6-inch focal length, aerial camera were also provided on a

mission request basis . (The film for the CA-8 camera system was supplied

by USAECOM , For t Monmouth , N .J).

After obtaining the necessary clearances , preliminary flights were

made over local military installations . These installations were Camp

A. P. Hill, Va., U.S.M .C. Base , Quantico , Va., Fc-~rt Meade , Md ., and Fort

Belvoir, Va. Of all of these locations , only the latter proved to have

the equipment and environment to meet the criteria of a variety of required target types, (both dispersed and clustered) and a number of vegetated and cleared areas . The rest of the criteria could be satisfied

by acquiring enough imagery , by film editing and processing , and by providing a means to determine ground resolution.

A tn -bar resolving power target chart was designed and constructed

by BESRL personnel. This 16’ by 48’ chart with a Brightness Ratio (contrast) of approximately 7:1 was spread out on an off—duty runway at

Quantico and photographed at the assigned altitude , before and after

each photo mission over Fort Belvoir . The widths of the tn —bars were

arbitrar ily made as follows : 24 , 16, 12 , 8, 4, 3, 2, 1— 3/4, 1—1/2,

1—1/4, 1, 3/4, and 1/2 inches with a length to width ratio of 5:1. As

one can see , the expectation was that the smallest resolvable ground

dimension (SRGD) would be among the smaller values where the differential between successive steps was small. However , this expectation was

not realized . Due to lack of a forward motion compensator in the CA-B

(a camera of Korean War vintage) the smallest resolvable known dimensions

on the imagery proved to be the 8-inch tn -bars of the chart when photographed at an altitude of 2 ,000 feet.

Two photo missions provided enough imagery to meet the requirement

for 50 target frames and 50 nontarget frames at 1:4,000 scale . The onehundred 70mm frames were cut from the CA-B ’s 9” x 9” imagery format .

In this manner greater latitude was possible in selecting the number of

targets (or lack of targets), the exclusion of other man-made objects ,

and the amount of cover . The target frames contained a target density

of 1—1 0 and a range of foliage cover 0% to 99%. The range of foliage

19 

__ _ , _ _ . .

~

___ _i

~

_ ,__ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~-

~- - -

~~~~~- ,- —~~~~~ -

cover for the nontarget frames also was 0% to 99%. Of the total of 113

targets, 22 of them were p~trtl y hidden . Six of the 50 target frames

con tained only partly hidden vehicles accounting for half of the total

of 22.

In order to be able to make a somewhat more meaningful comparison

between scales , almost all of the targets and their immediate surroundings are identical in both . This was accomplished as follows :

1. One hundred 70mm squares were cut from the second generation

positive 9” x 9” imagery at a scale of approximately 1:4,000.

Half of the frames contained targets . This comprised the smallscale set. (Note : there was no overlap from frame to frame

in this series.)

2. The 70mm square areas were marked off on the first generation

negative and these areas were enlarged photographically to

produce a second generation positive enlarged to a scale of

approximately 1:2,000.

3. The 100 large—scale frames were cropped back to 70mm size retaining almost all of the targets and their surrounding areas .

Consideration was also given to the amount of foliage cover

so that the large—scale frames closely approximated their small

scale counterparts in this respect.

4. The small—scale frames were then shuffled to randomize their

order and spliced together. The shuffling resulted in 11 target frames appearing in the first 25 frames , 13 in the second

25 , 11 in the third 25 , and 15 in the last 25. Black plastic

tape was used in the splicing and to make a border at top and

bottom leaving a 2-1/4” square imaged area in the center of

each frame .

5. The large-scale frames were placed in the same sequence as the

small—scale frames and also spliced together.

6. Since smooth imagery without splices was desired for the testing

machine , duplicate 4th generation positives were made of each

run of 100 frames.

This procedure produced two sets which were almost identical in target content, of the same format size and ground resolution, similar in

terrain features and foliage cover , but different in ground area coverage and size of the same imaged targets . An important feature is that

the information bits concerning the targets and their immediate surrounding areas are similar in both scales . In this study, resolution refers ,

not to the resolution of the imagery which is described in terms of lines

per sin or line pairs per sin, but rather to the smallest resolvable ground

dimension (SRGD) . The SRGD, according to the resolution charts , which

L 20
were photographed at the beginning and end of each photo mission , is

8 inches. There was no appreciable loss in SRGD from the first to the

fourth generation. The latter was used as the highest level of

resolution .

To obtain several levels of degraded imagery simulating transmitted

imagery at various bandwidths , a systematic procedure was followed . A

standard USAF Military Standard 150A resolution chart was calibrated to

match the BESRL Tn -bar Resolving Power Chart . The steps in calibration

were :

1. The 8” group of tn —bars (small scale imagery) was measured

along the long dimension on a Gilliland Point Coordinate Mensurator . The obtained size (average of 3 readings) was 360

microns.

2. Examination of the M. 5. 150?. resolution chart tn -bars showed

Group 3-Element 3, which measured 340 microns , to be closest to

the BESRL B” group .

3. The M. S. l5OA chart was enlarged slightly so that Group 3—

Element 3 tn -bars measured 360 microns.

4. The enlarged M. S. l5OA chart was degraded by defocusing the

camera lens to the point where Group 3—Element 3 tn —bars were

the smallest set resolvable on the chart. The two charts were

then equivalent in resolution and the M. S. 150?. with its finer

steps between intervals could serve as a better control in the

degradation steps to follow .

Frames containing two BESRL charts (one large scale and one small

scale) and three degraded (matching) M. S. l5OA charts were spliced at

each end of both the large scale and small scale imagery as controls .

Six successive generations were made using a base to base (opposite of

emulsion to emulsion) contact printing technique on a strip printer which

used a noncoherent light source. The two intermediate positive generations between the 4th generation positive and the final (10th) generation positive were selected for inclusion in the experiment . Fortuitous—

ly, the 6th , 8th , and 10th generation in turn were degraded approximately

to the point where the 12, 16, and 24 inch bars , respectively , were just

resolvable on the BESRL Tn -bar Resolving Power Chart. The M . S. 150?.

charts verified these values. Table A—l shows the appropriate set of

the calibrated M . S. 150?. Groups and Elements and their associated sizes

in inches on the ground .

21 

~

. —.-~~~~.

~~~~~~~~~~- --,~~~~~~ ~~~~~~~~~-—. ——.__
Table A-l

Selected Groups and Elements for the Enlarged Military Standard lO5A

Resolution Chart and Their Representative Ground Dimensions

Group Element Ground dimensionsa

3 3 8.00” (4th Generation Positive)

3 2 8.98”

3 1 10.08”

2 6 11.31” (6th Generation Positive)

2 5 12.70”

2 4 14.26”

2 3 16.00” (8th Generation Positive)

2 2 17.96”

2 1 20.16”

1 6 22.63” (10th Generation Positive)

1 5 25.40”

1 4 28.57”

a

The elements increase in size by the sixth root of 2.

In this study the lack of a camera with forward motion compensation (IMC) or an extremely fast shutter precluded acquisition of smaller

SRGD ’s--perhaps as small as 1 to 2 inches. Had these higher resolutions

been used then a wider range of imagery degradation could have been explored with respect to screening performance . In terms of line pairs per

millimeter , imagery resolutions of approximately 10 lp/mm to 1.7 lp/mm

were included in the study .

In future work a larger range of resolutions could be studied using

the same target types as in this experiment as well as smaller target

types such as personnel , foxholes , and gun explacements .

22

______ -

- 

-,- ~~~~~~~~ :

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

--— 

--a.
APPENDIX B

GENERAL BACKGROUND

The early detection of targets is almost universally conceded to

be of paramount importance in military operations . The most desirable

procedure , of course , would be to perform the detection or screening

operation in real—time , that is , at the same time as the imagery is

being acquired . This , however , is not possible in some instances . One

such instance occurs when photographic imagery is used .

The U.S. Army Electronics Command presently is experimenting with

the immediate processing of aerial photographs in survei llance aircraf t,

then electronically transmitting these photographs directly to a ground

station or via relay aircraft , and finally reprocessing the signals into

photographic imagery . The present state—of-the art requires about 10

seconds for the initial processing after photo acquisition , about 5

seconds transmission time, and about 10 seconds for final processing .

At this point the imagery is approximately 25 seconds delayed from

real-time . This delay is due entirely to current equipment limitations . The next limitation which will add further delay in photo interpretation is the time taken to visually screen a large amount of

imagery to select specific frames for more detailed analysis. Obviously, the shorter the time for screening the nearer to real—time

will be the photo interpretation .

This study is expected to determine what screening accuracy and

screening thoroughness can be expected for several different rates of

moving imagery .

L 23

L~~~~~~~~~~~. - —

- 

~~~

. 

.
_

APPENDIX C

TRAINING INSTRUCT IONS

During this training run and for the test run which will come later

on the other machine , you will screen each frame of imagery for wheeled

and/or tracked vehicles . Specifically, you will screen for tanks, trailers , trucks, bulldozers , cranes , front loaders , shovels , and automobiles .

The presence of at least one vehicle is sufficient to identify that particular frame as a target frame .

This run is simply a preliminary exercise to train you how to indicate which frames are target frames and which are not. This particular

set of imagery was selected so that frames with targets are quite obvious

as are those without targets . The important thing at this time is to

learn when to indicate your decision as to the presence or absence of

targets in any given frame .

To respond to a given frame , use the switch on the right leg of the

device. This switch has three positions : middle (neutral) , left (reject—

no-target) and right (accept-target) . All you need do is respond once

per frame--either reject or accept . Be sure to respond to every frame

containing imagery--do not respond to blank frames .

Now look into the viewing opening——you will see a green vertical

stripe on the left side of the frame mask. The imagery will be moving

from right to left. You may respond to a given frame any time any part

of that frame is behind the edge of the green stripe. Thus , if you see

a target just as a frame comes into view on the right side you must wait

until some part of this frame is behind the green stripe before you respond . If you respond either too soon or too late , a red light will go

on to let you know that you have responded to the wrong frame .

If the red light goes on even when you waited for the frame to get

behind the stripe , it means you have misinterpreted the frame . Don ’t

worry about the mistakes, as these are not being scored . Remember the

primary purpose of this short session is to train you to respond at the

proper time.

You may go through this run as many times as you ,~ish .

Are there any questions?

25

( 

. — -

I ~~

-E~EDIr.G BLk1~c

~NoT 
~ - . -

~~~~

APPENDIX D

EXPERI MENTAL RUN INSTRUCTIONS

You will screen each frame for targets, which shall be defined as

vehicles, specifically, tanks trailers , trucks , bulldozers , cranes , front

loaders , shovels, and automobiles . The presence of at least one vehicl e

is sufficient to identify that particular frame as a target frame . Respond to every frame , i.e., “target or no target ,” and respond only once

per frame .

You will respond to the frames in exactly the same way you just did

on the training device . The switch on the right leg of this device works

the same as the other , i.e., middle (neutral) , left (reject—no-target) ,

and right (accept-target) . You may respond to a given frame any time

any part of that frame is behind the edge of the green stripe.

These runs will differ from the last in three respects . First,

there will be no blank frames. Second , there will be no red light.

Third , you will see imagery at a number of different resolutions so you

can t-x p ect to see marked changes in image quality from time to time .

Are there any questions?

27 - — -

~~~~~ -~~~~~~~~— ~~-- ..

I 

I

~~C~DIN’ P~~~ ~ ~ ?IU4~D

— .— — 

— -

-
____ -

DISTRIBUTION

ARI D~~rlbution L

~~

4 OASO (M&IIAI 2 HQUSACDEC , Ft Ord, ATTN: Library

2 HODA (DAMI-cSZ) 1 HQUSACDEC , FtOrd, ATTN: ATEC—EX—E— Hum Factors

1 HQDA (DAI’E-PBR 2 USAEEC, Ft Benjamin Harrison, ATTN: Library

1 HODA IDAMA-AR) I USAPACDC, Ft Benjamin Harrison, ATTN: ATCP—HR

1 HODA (DA PE-HRE-PO ) 1 USA Comm-Elect Sch, Ft Monmouth, ATTN: ATSN-EA

1 HODA ISGRD-ID) 1 USAEC, Ft Monmouth, ATTN: AMSEL—CT—HDP

I HODA (DAMI-DOT-C) 1 USAEC, Ft Monmouth, ATTN: AMSEL—PA— P

I HODA IDAPC-PMZ-A) 1 USAEC, Ft Moomouth, ATTN : AMSEL—Sl—C B

1 HODA )DACH-PPZ-A) 1 USAEC, Ft Monmouth, AliN: C, Fact Div Br

¶ HQDA (OAPE-HREl 1 USA Materials Sys Anal Agry, Aberdeen, ATFN: AMXSY-P

1 HQDA DAPE-MPO.C) 1 Edgewood Arsenal, Aberdeen, ATI’N: SA REA—BL-H

1 HQOA (DA PE-OW) I USA Ord Cs & Scl’i, Aberdeen, AT1’N: ATSL—T EM—C

1 HQDA (DAPE-HRL) 2 USA Hum Engr Lab. Aberdeen. ATTN: Library/Dir

1 HQDA IDAPE-CPS) 1 USA Combat Arms Tng Sd, Ft Banning, AT1’N: Ad Supervisor

1 HODA IDAFD-MFA) 1 USA Infantry Hum Rich Unit, Ft Banning, A ’fl’N: Chi.f

1 HODA (DARD-ARS-P) I USA Infantry Sd, Ft Banning, ATTN: STEBC—TE—T

1 HODA IDAPC-PAS-A) 1 USASMA, Ft Bliss . ATrN ATSS—LRC

I HODA (DUSA-OR) 1 USA Air Oaf Sch, Ft Bliss , ATTN ATSA-CTD-ME

1 HODA IDAMO-ROR) 1 USA Air Dat Sch, Ft Bliis, ATTN: Tacit Lib

1 HODA IDASG) 1 USA Air Oaf Bd. Ft Bliss , ATTN: FILES

‘I HODA l0A10-Pl) 1 USA Air Oil Sd, Ft Bliss, ATTN: STEBD—PO

1 Ch ef Consult Div (DA-OTSG), Adelpiti. MD 1 USA Cmd & General SrI College, Ft Leavenworth, ATTN: Lib

I Ml Anti. Hum Ran, 000R&E, OAD (E&LS) 1 USA Cmd & General SrI College, Ft Leavenworth, Al-TN: ATSW—SE-L

1 (10 USARA L . APO Seattle. ATTN: ARAGP-R 1 USA CITId & General Sit College, Ft Leavenworth, ATTN: Ed Advisor

I HO First Army. ATTN: AFKA-OI-TI 1 USA Combined Arms Cmbt Dcv Act, Ft Leavenworth, ATTN: DepCdr

2 HO F,fth Army, Ft Sam Houston 1 USA Combined Arms Cmbt Dev Act, Ft Leavenworth. Al-TN: ccs

1 Dir. Army Sit Studies Otc. Al-TN: OAVCSA (DSP) I USA Combined Arms Cmbl Day Act, Ft Leavenworth, Al-IN: ATCASA

1 Ofc Chief of Sit, Studies Ofc 1 USA Combined Arms Cmbt 0ev Act, Ft Leavenworth, Al-TN: ATCACO-E

1 DCSPER, ATTN CPS~ )CP I USA Combined Artist Cmbt Des Act , Ft Lesvenworth, Al-IN: ATCACC—Cl

1 The Army Lib, Pentagon, ATTN: RSB Chief 1 USAECOM, Night Vision Lab, Ft Belvoir , ATTN: AMSEL—NV—SD

I The Army Lib, Pentagon, ATTN: ANRAL 3 USA Computer Sys Cmd. Ft Belvoir , Al-TN: Tech Library

1 Ofc, Asst Sect of the Army (R&D) I USAMERDC. Ft Belvoir. Al-TN: STSFB—DO

1 Tact, Support Ofc , Øj c~ 1 USA Eng Sch, Ft Belvoir , Al-TN: Library

1 USASA. Arlington, Al-TN: IARD-T 1 USA Topographic Lab, Ft B.Ivoir, Al-TN: ETL—T D—S

1 USA Rich Ofc, Durham, A l-rN: Life Sciences Dir I USA Topographic Lab, Ft Belvoir , Al-TN: STINFO Canter

2 USARIEM . Natick , ATTN: SGRD-UE-CA I USA Topographic Lab, Ft Balvoir , Al-rN: ETL—GSL

I USATTC . Ft Clayton, A TTN : STETC-MO-A I USA Intelligence Ctr & Scit. Ft Huacliuca, Al-TN: CTD—MS

I USAIMA, Ft Bragg, Al-TN: ATSU-CID-OM 1 USA Intelligence Ctr & Sch, Ft Huact,uca, Al-TN: ATS—CTD—MS

1 USAIMA . Ft Bragg. A TTN: Marqu.t Lib 1 USA Intelligence Ctr & Sch, Ft Huactsuca, ATTN: ATSI—TE

I US WA C Cs & Scti, Ft McClellan, Al-TN: Lib 1 USA Intelligence Cs & Sch, Ft Huachuca, ATT’N: ATSI—TEX—GS

I 1)5 WAC Ct, & Sch, Ft McClellan, Al-TN: Tng Dir 1 USA Intelligence Ctr & Sdi, Ft Huachuca, Al-TN: ATSI—CTS—OR

I USA Cesvtermant.r Sds, Ft Las, ATTN: ATSM-TE I USA %ntattigence Cs & Sets, It Huadsuca, ATTN: A’TS)—C’TD—O’T

1 l,it.lhgence Maser,aI Dew Ofc , EWL . Ft Holabird 1 USA Intelligence Cit & Sch, Ft Huactiuca. Al-TN: ATSI—CTD—CS

1 USA SE Sigoal Sch, Ft Gordon ATTN ATSO-EA 1 USA Intelligence Cit & Scit, Ft Huachuce, Al-rN: DAS/SRD

USA Chaplain Crr & Sdi, Ft Hamilton , Al-TN: ATSC-TE.RD 1 USA Intelligence Cs & Sch, Ft Huachuca. Al-TN: ATS I—TEM

1 USATSC H. Ft Euttis , ATTN . Educ Advisor 1 USA Intelligence Cit & Sch. Ft Huachuca, Al-TN: Libr~~y

1 USA War College. Cerlisle Banaclis, Al-TN: Lib I CDR , HO Ft Huaclsuca, ATTN: Tacit Ref Div

2 WRA I R, P’leuroosych.atr’y Div 2 COR . USA Electronic Prvg Grd, ATTN STEEP—MT—S

1 DLI . WA , Monter,y 1 COR , Pro(.ct MASSTER . Al-TN: Tact, Info Center

I LISA Concept Anal Aar-v Bethesda. ATTN MOCA-WGC I Hq MASSTER, USATRADOC, LNO - 1 USA Concept Anal Ago,. Bethesda . A TTN MOCA-MR 1 Research Institute , HO MASSTER, Ft Hood

I USA Concept Anal Aqcy, Bethesda, ATTN : MOCA-JF I USA R.aiiiting Cmd, Ft Sherdian, Al-TN: USARCP~~

—P

1 USA AttIc levi Ct,, APO Seattle . ATTN STEAC-MO’ASL, I Senior Army Ads., USAFAGOD/TAC , Elgin AF Aux FId No. 9

I L/8A A ,,r TeeS Ct, API) Seattle ATTN AMSTE-PL-TS I HO USARPAC, DCSPER, API) SF 96668, Al-TN: GPPE—SE

1 USA A,-’-

~~’-.-’ Cn,d. ~edasons Arsenal, ATTN AISK-TEN 1 Stlmson Lib, Academy of Health Sciences, Ft Sam Houston

LISA Armament Cmd. Rod, Island , Al-iN AMSAR-TOC I Marine Corp. leet ., Al-TN: Dean—MCI

I FAA NAF EC . Atlantic C s’, A TTN Ijbrary I HOUSMC, Commandant, ATTN : Code MIMI SI

1 FAA NAFEC , Atlant ic City , AUTh- Hunt Er~

g Br 1 HOUSMC. Commandant, Al-TN: Code MPI—20

I FAA Aaronaut,cal Crr . Oklahoma Cr y Al-TN: AAC-440 2 USCG Academy New L

~tidon, Al-TN: Admilsion

2 USA FM Arty S.- r Ft SIN, A TTN Library 2 USCG Academy. New London, Al-TN: Library

1 LiSA Ar m or Scit ~Iknoe ATTN Library I USCG TrainlngCtr ,NV ,ATTN: CO

I USA U nto, li-f’ Ft Kr.oe, ATTN Al-SB-DI E I 1)5CC Training Cit. NY , Al-TN: Edisc Svc Ofc

I US~ fr.j,no

~ ~.-r Ft ~ non ATT N ATS$-DT 1’! ¶ USCG. Psycisol Ran Br, DC, Al-TN: GP 1/82

I (IS A Armor li-r F, Kno,., ATT N ATSN.C0-AD 1 HO Mid-Range Br, MC Oat , Ouantloo, Al-TN: P&S Div

29

I

. 

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

- -- - - .

‘

~ l

~~ CEDIr;G PAGE ~

-L~~~C-NOT FILMED 

., - -~~~~~~~~ -- - - . -

________ - ----

~~

,---~~~~~~~~~~~~~
~~~—-—- - .—~~~~~~~~~--- -—-~~~~-- -

~~~~~~ - - —~~~~~~~ --- -~~~~~~~~~

- --—-, ,

_

1 US Marina Corps Liaision Otc , AMC, Alexandria , ATTN: AMCGS—F 1 O.f & CIvil Inst of Enviro Medicine, Canada

I USATRADOC, Ft Monroe, ATTN: ATRO—ED I AIR CRESS, kasseiniton, Al-TN: Info Sys Sr

6 USATRADOC, Ft Monroe, ATTPI: Al-PR-AD * MlIiteerpsykologld~ Tiseseste, Cocahegsn

1 USATRADOC, Ft Monroe. All-N: ATTS—EA 1 Military Attach.. French Embassy . Al-TN: Doc Sec

I USA Forces Cmd, Ft McPherson, ATTN: Library 1 Medecin Chef. C.E.R.P,A.—Arsenal, Toulon/Naval France

2 USA Aviation last Sd, Ft Bucker, ATTN: Sl-EBG—PQ 1 Prin Scientific Off , A91 Hw,s Sec Rids Dlv, MiniWry

1 USA A~~y for Aviation Safety , Ft Bucker , ATTN: Library of Defense , New Delhi

1 USA Agcy for Aviation Satety , Ft Rucker, Al-TN: Educ Advisor 1 Pits Bach Oft Library, AKA. Israel Defense Forcei

I USA Aviation Scit, Ft Bucker . ATTN: PD Drawer 0 ¶ Ministaris van Detsnsla, 000P/KL Al d Soclaal

1 HOUSA Aviation Sys Cmd, St Louis, ATTN: AMSAV—ZDR Psychologiscit. Zaken , The Hague, Netherlands

2 USA Av Iati on Sys hit Act., Edwards AFB, ATTN: SAVTE—T

1 USA Air Oaf Sets, Ft Bliss, Al-TN: ATSA TEM

1 USA Air Mobility Rich & Div Lab, Moffet t FId. Al-TN: SAVDL—AS

1 USA Aviation Sth, Res Tng Mgt, Ft Rucker , ATTN: Al-ST—T—RTM

1 USA Aviation Sets, CO. Ft Rucker, ATTN: ATST—D—A

I HO, OARCOM . Alexandria, ATTN: AMXCD—TL

1 HO, DARCOM , Alixandria, ATTN: CDR

1 US Military Academy, West Point, ATTN: Serials Unit

1 US Military Academy, West Point, ATTN: Ofc of MIt Ldrshp

1 US Military Academy, West Point, ATTN: MAOR

I USA Standardization Gp, UK, FPO NY , ATTN: MAS E—GC

I Ofc of Naval Rich, Arlington, Al-TN: Code 452

3 Ofc of Naval A scIi, Arlington, ATTN: Coda 458

I Ofc of Nav~I Rich, Arlington, ATTN: Code 450

1 Ofc of Naval Rich, Arlington, AUN: Code 441

1 Naval Aeroipe Med Ret Lab . Pensacola, ATTN: Acous Sch Div

1 Naval Aaroapc Med Ret Lab. Pensacola , ATTN: Code L51

1 Naval Aerospc Med Ret Lab, Pensacola , Al-TN: Code LB

1 Chief of NavPers , ATTN: Pert-OR

1 NAVAIRSTA , Norfolk, ATTN: Safety Cit

1 Nat Oceanographic , DC, ATTN: Code 6251. Charts F. Tacit

1 Center of Ntval Anal, Al-TN: Doe Cit

1 NavAirSysCom, ATTN: AIR—53 13C

1 Nat BuMed, Al-TN: 713

1 NavitelicopterSubSgua 2, FPO SF 96601

1 AFHRL lET) William APR

1 AFI-IRL(TT) Low,’y AFB

I AFHRL (AS) WPAFB , OH

2 AFHP.L )DOJZ) Brooks AFB

1 AFHRL (DOJN) Lackland AFB

1 HOUSAF (INYSO)

1 HOUSAF (DPXXA)

1 AFVTG (RO) Randolph APR

3 AMRL (HE) WPAFB, OH

2 AF Inst of Tech, WPAFB , OH, ATTN: ENE/SL

1 Al-C )XPl-D) Randolph AFB

1 USAF AeroMed Lib, Brooks AFB )SUL—4), All-N: DOC SEC

1 AFOSR INL(, Arlington

1 AF Log Cmd, McClellan AFB. ATTN: ALC/DPCRB

I Air Force Academy, CO. Al-UN: Dept of Bel Sen

5 NavPers & Dcv Ctr , San Diego

2 Navy Med Neuropsychiatric Rich Unit , San Diego

1 Nay Electronic Lab, San Diego, ATTN: Ret Lab

1 Nay TrngCen, San Diego , Al-IN: Code 9000- Lib

1 NavPostGraScls , Monterey, ATIN: Code 55Aa

I NavPostGraSch . Monterey, ATTN: Code 2124

1 Nav lrngEquipCtr, Orlando, ATTN: Tech Lib

1 US Dept of Labor, DC, Al-TN: Manpower Admin

1 US Dept of Justice, DC, All -N: Drug Enforce Admin

1 Nat But of Standards, DC, A TTN : Computer Info Section

1 Nat Clearing House for MR— Info, Rockville

1 Denver Federal Ctr, Lakewood, ATTN: BLM

12 Defense Documentation Center

4 Dir Psych, Army Hg, Russell Ofcs, Canberra

I Scientific Advsr, Mil Rd. Army Hg, Russell Otci, Canberra

I Mil and Air Attache, Austrian Embassy

1 Centre de Reelsetche Des Facteurs , Humaine tIe Ia Defense

Nationale , Brussels

2 canadian Joint Staff Washington

1 C/Air Staff, Royal Canadian AF . ATTN: Pert Sad Anal Br

3 Chief, Canadian Di Rich Staff , ATTN: C/CRDS(W1

4 British Del Stiff . British Embassy. Washington

30

- -- - . _. -

~

-- .-- . ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~