ALOS-2/PALSAR-2
Level 1.1/1.5/2.1/3.1 GeoTIFF ProductFormat Description

May 23, 2014

Japan Aerospace Exploration Agency

PALSAR-2
Level 1.1/1.5/3.1 GeoTIFF ProductFormat Description

Japan Aerospace Exploration Agency

ALOS-2 Product Format Description
GeoTIFF Level 1.1/1.5/3.1 Revision History (1/1)
Rev.

Date

Revision ContentsNC

2012/12/28

First EditionA

2014/5/16

P5

RemarkAdded the description about storing data as BigTIFF.
P6 Table 3-1
Revised

the

tag

type

of

“ImageWidth”

and“ImageLength”.
Before: LONG
After: SHORT or LONG
P7 Table 3-1
Revised the remark of “Orientation”.
Before:3 = row: Bottom to Top, column: Left to Right4 = row: Bottom to Top, column: Right to Left
After:
3 = row: Bottom to Top, column: Right to Left
4 = row: Bottom to Top, column: Left to Right
P16
Added the description that the offset value “B” is set to
0 in the case of L1.1 data.
P17-24
Added Section 4. “Summary information.”

ALOS-2 Product Format Description(GeoTIFF Level 1.1/1.5/3.1)
Table of Contents
1. Overview ...........................................................................................................................................1
2. Product Specifications ......................................................................................................................2
2.1. Outline of GeoTIFF Standard ....................................................................................................2
2.2. Composition of Product .............................................................................................................2
2.3. Filename .....................................................................................................................................3
3. Format ...............................................................................................................................................5
3.1. GeoTIFF File .............................................................................................................................5
3.1.1. Common TIFF Tag ..............................................................................................................5
3.1.2. GeoTIFF tag of Level 1.1 Product ......................................................................................8
3.1.3. GeoTIFF tag of level 1.5 and level 3.1 Product ................................................................ 11
3.2. Look Up Table .........................................................................................................................16
4. Summary Information .....................................................................................................................174.1. Outline of Summary Information .............................................................................................174.2. Filename of Summary Information ..........................................................................................174.3. File Format of Summary Information ......................................................................................174.3.1. Format Definition of Keyword .........................................................................................17
4.3.2. Format Definition of Value ...............................................................................................174.3.3. Contents of Summary Information....................................................................................17i1. Overview
This document describes the format specifications for ALOS-2 GeoTIFF Level 1.1/1.5/3.1 products
which are generated with ALOS-2 Data Processing System.

12. Product Specifications
2.1. Outline of GeoTIFF Standard
GeoTIFF is a metadata standard, which allows geometric information to be embedded within
Aldus-Adobe’s raster Tagged Image File Format (TIFF) file.
2.2.Composition of Product
ALOS-2 GeoTIFF product is generated from ALOS-2 Level 1.1/1.5/3.1 processed data, except
Level 1.1 data of ScanSAR mode. GeoTIFF product contains some pairs of GeoTIFF files and LUT(Look-Up Table) files according to the number of polarizations. The LUT is required in order toconvert each pixel value (integer) into a Sigma-Naught value (Real). Figure 2-1 shows a block
diagram of GeoTIFF product. Table 2-1 shows the number of GeoTIFF/LUT files in each observation
mode.

GeoTIFF Product

1…4

1…4

GeoTIFF File

LUT

Figure 2-1 Block Diagram of GeoTIFF Product

Table 2-1 Relationship between number of GeoTIFF/LUT Files and Observation Mode
Observation mode

SingleDual

Full (Quad)

GeoTIFF

1

2

4

LUT

1

2

4

(Number of Polarizations)22.3. Filename
The filename definitions of GeoTIFF product and LUT are shown in Table 2-2.
Table 2-2 Filename Definition of ALOS-2 GeoTIFF ProductFile Type
GeoTIFFIMG-XX- Scene ID-Product ID.tif
LUT-XX- Scene ID

LUT
Scene ID

Definition of Filename-Product ID.txt

Contents
The file of GeoTIFF form. An integer value isindicated to each pixel. Geographic information andmap projection are written in the header.
The text file which summarizes the conversion factor
for changing each pixel value (integer) of a GeoTIFF
file into a Sigma Naught value (real).

= AAAAABBBBBCCCC-YYMMDDAAAAA : Satellite ID = 'ALOS2'BBBBB: Orbit accumulation number of a scene center

CCCC: Scene frame number of a scene center-: Separator (hyphen)

YYMMDD : Observation date of a scene center(YY: lower 2 figures of a year, MM: month, DD: day)
Product ID = DDDEFFFGHI
DDD: Observation Mode
( SBS : Spotlight mode
UBS : Ultra-fine mode Single polarization
UBD : Ultra-fine mode Dual polarization
HBS : High-sensitive mode Single polarization
HBD : High-sensitive mode Dual polarization
HBQ : High-sensitive mode Full (Quad.) polarimetry
FBS : Fine mode Single polarization
FBD : Fine mode Dual polarization
FBQ : Fine mode Full (Quad.) polarimetry
WBS : ScanSAR nominal [14MHz] mode Single polarization
WBD : ScanSAR nominal [14MHz] mode Dual polarization
WWS: ScanSAR nominal [28MHz] mode Single polarization
WWD: ScanSAR nominal [28MHz] mode Dual polarization
VBS : ScanSAR wide mode Single polarization
VBD : ScanSAR wide mode Dual polarization )E: Observation Direction (L: Left looking, R: Right looking)

FFF: Processing Level(1.1: Level 1.1, 1.5: Level 1.5, 3.1: Level 3.1)

G

: Processing Option(G: Geo-Coded, R: Geo-Reference, _: Not specified (underscore))3

H: Map Projection(U: UTM, P: PS, M: MER, L: LCC, _: Not specified)I: Orbit Direction(A: Ascending, D: Descending)Polarization (Transmission and Receiving) = XX
HH : Horizontally polarized wave transmission / Horizontally polarized wave receiving
HV :Horizontally polarized wave transmission / Vertically polarized wave receiving
VH :Vertically polarized wave transmission / Horizontally polarized wave receiving
VV : Vertically polarized wave transmission / Vertically polarized wave receiving

43. Format
3.1. GeoTIFF File
GeoTIFF is a metadata standard which allows geometric information to be embedded within a TIFF
image file. In ALOS-2 GeoTIFF products, GeoTIFF files are generated in TIFF-Strip format, andsome GeoTIFF-tags (identifiers) are different in each processing level. All TIFF files and
GeoTIFF-tags are based on TIFF Revision 6.0 and GeoTIFF Revision 1.0 standard, and image data isrecorded in little endian.
Since TIFF format supports 4 GB image size in maximum, the image which exceeds 4 GB is stored A
in BigTIFF format.
3.1.1. Common TIFF Tag
Some TIFF-tags common to all processing levels are shown in Table 3-1.

5

Tag nameImageWidth

Table 3-1 Common TIFF-tags in All Processing Levels (1/2)
Description
Number of pixels in one line.

BitsPerSample

Tag type
SHORT orLONG
SHORT or
LONG
SHORT

Compression

SHORT

PhotometricInterpretation

SHORT

Color space type of bitmap image data
= 1 (fixed value)

ImageDescription

ASCII

Polarization of Tx and Rx= 'HH', 'HV', 'VH', 'VV'

ImageLength

RemarkNumber of lines.
Number of bits in one sample
L1.1 = 16, 16 (fixed value)
L1.5 = 16 (fixed value)
L3.1 = 16 (fixed value)Compression type = 1 (fixed value)

6

L1.1: 16bit, 16bit (real part, imaginary part)L1.5: 16bit (absolute value)
L3.1: 16bit (absolute value)
1 = No compression
2 = ITU-T modified Huffman RLE
3 = ITU-T Group 3 fax encoding
4 = ITU-T Group 4 fax encoding
5 = LZW (fixed-length) compression
6 = JPEG compression (old style)
7 = JPEG compression (new style)
8 = ZIP compression
32773 = Packbits compression
0 = WhiteIsZero(Pixel value: White=0, Black =(2^BitsPerSample-1))
1 = BlackIsZero(Pixel value: Black=0, White=(2^BitsPerSample-1))
2 = RGB direct color(min=0 as black, max=(2^BitsPerSample-1) as white)
3 = Palette color(min=0, max=(2^BitsPerSample-1))
4 = Transparency Mask (definition of masked region)
In order of Tx and Rx

ATag name
Orientation

Tag type
SHORT

SamplesPerPixel

SHORT

PlanarConfiguration

SHORT

SampleFormat

Array of
SHORT

Table 3-1 Common TIFF-tags in All Processing Levels (2/2)
Description
RemarkOrientation of image = 1 (fixed value)
1 = row: Top to Bottom, column: Left to Right2 = row: Top to Bottom, column: Right to Left
3 = row: Bottom to Top, column: Right to Left
4 = row: Bottom to Top, column: Left to Right
5 = row: Left to Right, column: Top to Bottom
6 = row: Right to Left, column: Top to Bottom
7 = row: Right to Left, column: Bottom to Top
8 = row: Left to Right, column: Bottom to Top
Number of samples in one pixel
L1.1: 2 (real part, imaginary part)L1.1 = 2 (fixed value)
L1.5: 1 (absolute value)
L1.5 = 1 (fixed value)
L3.1: 1 (absolute value)
L3.1 = 1 (fixed value)
Storing order of the data = 1(fixed value)
1 = Chunky format: The component values for each pixel are
stored contiguously
2 = Planar format: The components are stored in separate
components.
L1.1: IQIQIQ…
L1.5: MMM…
L3.1: MMM…
Type of data
1 = unsigned integer
L1.1 = 2, 2(fixed value)
2 = signed integer
L1.5 = 1(fixed value)
3 = float
L3.1 = 1(fixed value)
4 = undefined
5 = complex integer
6 = complex float
The number of elements of the array is equal to the value of“SamplePerPixel” tag7A3.1.2. GeoTIFF tag of Level 1.1 Product
GeoTIFF tags of ALOS-2 Level 1.1 processed GeoTIFF product are shown in Table 3-2.

8

Tag name
GeogLinearUnitsGeoKey
GeogAngularUnitsGeoKey
ModelTiepointTag

Tag type
SHORT
SHORT
DOUBLE

Table 3-2 GeoTIFF-tags of Level 1.1 Product (1/2)
Description
RemarkGeographical unit (length) = 9001 (fixed value)
9001 = Linear_Meter[m]Geographical unit (angle) = 9102 (fixed value)
9102 = Angular_Degree[deg]The coordinate value on the map corresponding to the point of
the four corners of TIFF image
In N [pixels] × M [line] image:(Pixel No., Line No., 0.0,=(
0.5,
0.5, 0.0,
0.5,
M-0.5, 0.0,
N-0.5,
0.5, 0.0,
N-0.5,
M-0.5 , 0.0,

GTModelTypeGeoKey

SHORTLongitude, Latitude, 0.0)
Lon1,
Lat1, 0.0,
Lon2,
Lat2, 0.0,
Lon3,
Lat3, 0.0,
Lon4,
Lat4, 0.0)

Coordinate system type = 2 (fixed value)

9

1 = ModelTypeProjected (Projection Coordinate System)
2 = ModelTypeGeographic(Geographic Latitude-Longitude System)
3 = ModelTypeGeocentric(Geocentric (X,Y,Z) Coordinate System)

Tag name
GTRasterTypeGeoKey

Tag type
SHORT

Table 3-2 GeoTIFF-tags of Level 1.1 Product (2/2)
Description
RemarkAlignment of pixel value = 1 (fixed value)
1 = PixelIsArea
The first pixel applies the domain surrounded by (0, 0), (0,1), (1, 0), and (1, 1). The center of pixel is located in (0.5,
0.5).
0
0.5
1

0
0.5
1
2 = PixelIsPoint
The first pixel applies the domain surrounded by (-0.5,-0.5),(0.5,-0.5), (-0.5, 0.5), (0.5,0.5). The center of pixel is locatedin (0,0).

-0.5
-0.5
0
0.5

10

0

0.5

1

3.1.3. GeoTIFF tag of level 1.5 and level 3.1 Product
GeoTIFF tags of ALOS-2 Level 1.5/3.1 processed GeoTIFF products are shown in Table 3-3.

11

Tag name
GTCitationGeoKey

Tag type
ASCII

GeogLinearUnitsGeoKey
GeogAngularUnitsGeoKey
ProjLinearUnitsGeoKey
GeogPrimeMeridianGeoKey
ModelPixelScaleTag

SHORT
SHORT
SHORT
SHORT
DOUBLE

ModelTiepointTag

DOUBLE

ModelTransformationTag

DOUBLE

Table 3-3 GeoTIFF-tags of Level 1.5 and Level 3.1 Product (1/4)
Description
RemarkProcessing option
Geo-coded= 'Geo-coded'
Geo-reference = 'Geo-reference'
Coordinates unit (length) = 9001 (fixed value)
9001 = Linear_Meter[m]Coordinates unit (angle) = 9102 (fixed value)
9102 = Angular_Degree[deg]Projection coordinates unit (length) = 9001 (fixed value)
9001 = Linear_Meter[m]The position of the standard meridian line = 8901 (fixed value)
8901 = PM_Greenwich (Greenwich meridian)
The size of a pixel = (pixel width, line width, 0.0)
Units of width are as same as “GeogLinearUnitsGeoKey”
and “ProjLinearUnitsGeoKey”. [m]Correspondence of pixel-line coordinates and map coordinates.
(Pixel no., Line no, 0.0, Map-addr. X, Map-addr. Y, 0.0)=(
0.5,
0.5, 0.0, Map-addr. X, Map-addr. Y, 0.0)
The conversion matrix from a pixel and line coordinates to map When (pixel no., line no.) = (P, L);
coordinates
Map address X = a * P + b * L + d= (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p)
Map address Y = e * P + f * L + h
In a two-dimensional coordinate plane,
Map address X
a b 0 dPixel no.
Map address Y
e f 0 hLine no.
=0
0 0 0 001
0 0 0 11
= (a, b, 0, d, e, f, 0, g, 0, 0, 0, 0, 0, 0, 0, 1)

12

Tag name
GTModelTypeGeoKey

Tag type
SHORTGTRasterTypeGeoKey

SHORT

Table 3-3 GeoTIFF-tags of Level 1.5 and Level 3.1 Product (2/4)
Description
RemarkCoordinate system type = 1 (fixed value)
1 = ModelTypeProjected (Projection Coordinate System)
2 = ModelTypeGeographic(Geographic Latitude-Longitude System)
3 = ModelTypeGeocentric(Geocentric (X,Y,Z) Coordinate System)
Alignment of pixel value = 1 (fixed value)
1 = PixelIsArea
The first pixel applies the domain surrounded by (0, 0), (0, 1), (1, 0), and (1,1). The center of pixel is located in (0.5, 0.5).
2 = PixelIsPoint
The first pixel applies the domain surrounded by (-0.5,-0.5), (0.5,-0.5), (-0.5,0.5), (0.5, 0.5). The center of pixel is located in (0, 0).
1)

0

0.5

1

2)

-0.5

0

0.5

-0.5
0
0
0.5
0.5
1
1

GeogGeodeticDatumGeoKey

SHORT

GeogEllipsoidGeoKey
ProjectedCSTypeGeoKey

SHORT
SHORT

Geographic coordinate system = 6655(fixedvalue)
Ellipsoid code = 7019 (fixed value)
Map projection code
User defined = 32767 (fixed value)

136655 = The International Terrestrial Reference Frame 1997(ITRF97)
7019 = Ellipse_GRS_1980(GRS80)
In all the projection system, the value “User defined” is set

1

Table 3-3 GeoTIFF-tags of Level 1.5 and Level 3.1 Product (3/4)
Description
RemarkMap projection code
In a case of other than UTM, the value “User defined” is set.
UTM projection
Northern Hemisphere = 16000 + Zone no.
Southern Hemisphere = 16100 + Zone no.
PS / MER / LCC projection
User defined = 32767 (fixed value)
GeographicTypeGeoKey
SHORT
Map coordinate code = 4338 (fixed value)
4338 = ITRF97
GeogCitationGeoKey
ASCII
Specify a geographic coordinate system, an ellipsoid model,
and a map projection system.
= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=UTM'= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=PS'= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=MER'= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=LCC'
The following tag is specified only when “ProjectionGeoKey” is set as “user defined” (32767)
ProjCoordTransGeoKey
SHORT
Map projection code
PS projection
PS projection = 15 (fixed value)
15 = CT_PolarStereographic
MER projection = 7 (fixed value)
MER projection
LCC projection = 8 (fixed value)
7 = CT_Mercator
LCC projection
8 = CT_LambertConfConic_2SP
On the following tags, only the parameter needed in the selected map projection is specified.
ProjNatOriginLongGeoKey
DOUBLE Longitude of the map-projection natural origin
The unit specified in “GeogAngularUnitsGeoKey” is [deg].
In UTM and PS projection:
The map-projection natural origin of UTM and PS
projection is specified in “ProjFalseEastingGeoKey”.
Center longitude of projection is specified
The natural origin of northern hemisphere corresponds to
In MER and LCC
negative value of map coordinate y, and that of southern
The longitude of the map starting point is specified.
hemisphere, positive value, in the case of PS projection.
ProjNatOriginLatGeoKey
DOUBLE Latitude of the map-projection natural origin
The unit specified in “GeogAngularUnitsGeoKey” is [deg].
In UTM and PS projection:
The map-projection natural origin of UTM and PS
projection is specified in “ProjFalseNorthingGeoKey”.
The center latitude of projection is specified
In MER and LCC
The latitude of the map starting point is specified.
Tag name
ProjectionGeoKey

Tag type
SHORT

14

Table 3-3 GeoTIFF-tags of Level 1.5 and Level 3.1 Product (4/4)
Tag name
Tag type
Description
RemarkOn the following tags, only the parameter needed in the selected map projection is specified.
ProjFalseEastingGeoKey
DOUBLE The easting value from the map-projection natural origin (to The unit specified in “ProjLinearUnitsGeoKey” is used [m]determine the map natural origin).
It is specified only in the case of UTM projection.
= 500000.0 (fixed value)
ProjFalseNorthingGeoKey
DOUBLE The northing value from the map-projection natural origin (to The unit specified in “ProjLinearUnitsGeoKey” is used [m]determine the map natural origin).
It is specified only in the case of UTM projection.
Northern Hemisphere = 0 (fixed value)
Southern Hemisphere = 10000000.0 (fixed value)
ProjStdParallel1GeoKey
DOUBLE Latitude of primary standard parallel.
The unit specified in “GeogAngularUnitsGeoKey” is used
It is specified only in the case of LCC projection[deg]
ProjStdParallel2GeoKey
DOUBLE Latitude of second standard parallel.
The unit specified in “GeogAngularUnitsGeoKey” is used
It is specified only in the case of LCC projection[deg]
ProjScaleAtNatOriginGeoKey DOUBLE Scale factor at natural origin
non-dimension
It is specified only in the cases of UTM and PS projection.
UTM = 0.9996 (fixed value)
PS = 1.0 (fixed value)153.2. Look Up Table
The LUT is the text file which records the conversion factor for converting from the integer value
stored in each pixel of a GeoTIFF file into a real value ( σ 0 : Sigma Naught). The conversion equations
for the level 1.1 and for the levels 1.5/3.1 are shown below.
• Level 1.1

σ =0Here, C

2

C

2

3-1

A2

= I 2+Q 2 . C is pixel value as complex-integer. I is real part of C, and Q is

imaginary part of C. To change integral values into real values, use following expression:

I real =Q
I, Qreal =A
A• Level 1.5 and Level 3.1

σ0 =(M + B )

3-2

2

A

3-3

Here, M is pixel value as unsigned integer. A is the coefficient which only depends on therange direction. B is an offset value and is common to all the pixels. In the case of level 1.1
products, B is set to 0.

An example of LUT file is shown in Table 3-4. Here, N is the number of pixels in one line.

Table 3-4 Example of LUT Format
Line 1
offset value B
Line 2
scaling factor A[0]Line 3
scaling factor A [1]
.
.
.
.
.
.
Line (N+1)
scaling factor A [N-1]
However, all A is the same value in the geocoded product of the levels 1.5/3.1.
A [dB] value () is converted by using following formula:

16

A

A

4.Summary Information
The summary information on GeoTIFF level 1.1/1.5/3.1 is shown in below.

4.1. Outline of Summary Information
The summary information file includes the information for creating processed data created at
ALOS-2 Data Processing System, and it is always made in a pair with its processed data.

4.2. Filename of Summary Information
The filename of summary information is fixed as follows.
summary.txt

4.3. File Format of Summary Information
The summary information file consists of some record lines which use LF (line feed code) as atermination, and does not include header information, footer information, etc. A record line consists ofa keyword, an equal mark (=), and a value. A summary information file format outline is shown in
Figure 4-1.
Keyword

=

Value

LF

…

…

…

…

Keyword

=

Value

LF

Figure 4-1 Outline of Summary Information File Format
4.3.1. Format Definition of Keyword(1)

The keyword is stored from the head of a record line.

(2)

The equal mark ‘=’ is stored after the keyword.

(3)

There is no blank character between a keyword and ‘=’, in principle.

4.3.2. Format Definition of Value(1)

The value is a text string bundled with double quotation letters (“).

(2)

The value can contain alphabets, digits, and some special characters (except for double
quotation). Numerical values are also stored as an ASCII string.

(3)

There is no blank character between ‘=’ and the former double quotation letter, in principle.

4.3.3. Contents of Summary Information

The items of the GeoTIFF Level 1.1/1.5/3.1 summary information are described in Table 4.3-1.
"b" in a table means blanks.

17

No.
1

Section
Ordering
information
(Odi)

2

3

4

Scene
specification(Scs)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (1/8)
Item name
KeywordValue
Scene description ID
Odi_SceneId
ID for specifying a scene uniquely'AAAAAAAAAAAAAAAA-NNNNN-xxx-nnn'
AAAAAAAAAAAAAAAA: Operation Segment No
NNNNN: Observation ID
xxx: 001～999
nnn: Scene no.
Processed
Odi_SiteDateTime
Spacecraft Control Mission Operation system
Site/Date/Time= 'PROCESS: JAPAN-JAXA-ALOS2-SCMObbYYYYMMDDbHHMMSS'
Earth Intelligence Collection and Shearing System= 'PROCESS: JAPAN-JAXA-ALOS2-EICSbbYYYYMMDDbHHMMSS'YYYYMMDD : Processed date (YYYY: year, MM: month, DD: day)
HHMMSS: Processed time (UTC)
Scene ID
Scs_SceneID'AAAAABBBBBCCCC-YYMMDD'AAAAA : Satellite name (='ALOS2')BBBBB : Orbit accumulation number of a scene center
CCCC : Scene frame number of a scene center: separator (hyphen)
YYMMDD: Observation date of scene center
Amount of scene
Scs_SceneShift'-5'～'4' : Except ScanSAR mode
shift'-25'～'20' : ScanSAR mode
Zero and positive number have no sign.

18

A

No.
5

Section
Product
specification(Pds)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (2/8)
Item name
KeywordValue
Product ID
Pds_ProductID'DDDEFFFGHI'
DDD: Observation mode
SBS: Spotlight mode
UBS: Ultra-fine mode (Single pol.)UBD: Ultra-fine mode (Dual pol.)
HBS: High-sensitive mode (Single pol.)
HBD: High-sensitive mode (Dual pol.)
HBQ: High-sensitive mode (Full (Quad.) pol.)FBS: Fine mode (Single pol.)FBD: Fine mode (Dual pol.)FBQ: Fine mode (Full (Quad.) pol.)
WBS: ScanSAR nominal [14MHz] mode (Single pol.)
WBD: ScanSAR nominal [14MHz] mode (Dual pol.)WWS: ScanSR nominal [28MHz] mode (Single pol.)
WWD: ScanSAR nominal [28MHz] mode (Dual pol.)
VBS: ScanSAR wide mode (Single pol.)VBD: ScanSAR wide mode (Dual pol.)E : Observation direction
L: Left looking, R: Right looking
FFF: Processing level
1.0: Level 1.0, 1.1: Level 1.1, 1.5: Level 1.5,
3.1: Level 3.1
G : Processing option
G: Geo-Coded, R: Geo-Reference, _ : n/a (underscore)H : Map projection type
U: UTM, P: PS, M: MER, L: LCC, _ :n/a (underscore)
I : Orbit direction
A: Ascending, D: Descending

19

A

No.
6
7
8
9
10
11
12
13
14

Section
Product
specification(Pds)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (3/8)
Item name
KeywordValue
Resampling method
Pds_ResamplingMethod'NN' / 'BL' / 'CC' (specify only for level 1.5/3.1 product)
Nearest Neighbor / Bi-Linear / Cubic Convolution
UTM zone no.
Pds_UTM_ZoneNo'1'～'60' (specify only for level 1.5/3.1 UTM projected product)
PS reference latitude
Pds_PS_ReferenceLatitude
Northern Hemisphere: '90.000', Southern Hemisphere: '-90.000'(specify only for level 1.5/3.1 PS projected product)
PS reference
Pds_PS_ReferenceLongitude'-179.999' ≤ reference longitude ≤ '180.000'
longitude(specify only for level 1.5/3.1 PS projected product)
LCC reference
Pds_LCC_ReferenceLatitudinalLine1'-90.000' < reference latitude < '90.000'
latitudinal line 1(specify only for level 1.5/3.1 LCC projected product)
LCC reference
Pds_LCC_ReferenceLatitudinalLine2'-90.000' < reference latitude < '90.000'
latitudinal line 2(specify only for level 1.5/3.1 LCC projected product)
Map direction
Pds_MapDirection'MapNorth'(specify only for level 1.5/3.1 geocoded product)
LCC origin latitude
Pds_LCC_OriginLatitude'-90.000' ≤ origin latitude ≤ '90.000'(specify only for level 1.5/3.1 LCC projected product)
LCC origin longitude Pds_LCC_OriginLongitude'-179.999' ≤ origin longitude ≤ '180.000'(specify only for level 1.5/3.1 LCC projected product)

20

A

No.
15
16

Section
Product
specification
(Pds)

17
18
19
20

21
22
23
24
25
26
27

Image
information(Img)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (4/8)
Item name
KeywordValue
Pixel spacing
Pds_PixelSpacing
unit: m(specify only for level 1.5/3.1 product)
Precision of orbit
Pds_OrbitDataPrecision'Precision' / ' Onboard ' / 'RARR_Predict'
data
Precision: High precision orbit information
Onboard: Onboard orbit determination
RARR_Predict : Predicted orbit information
Precision of attitude
Pds_AttitudeDataPrecision'Onboard'data
Onboard : Onboard attitude determination
Date and time of
Img_SceneCenterDateTime'YYYYMMDDbhh: mm: ss.ttt'(UT)
scene center
YYYY : Year (A.D.)
MM : Month (01～12)
Date and time of
Img_SceneStartDateTime
DD : Day (01～31)
scene starthh: Hour (00～23)
Date and time of
Img_SceneEndDateTime
mm : Minute (00～59)
scene endss
: Second (00～60) (ss=60 is used only by a leap second.)
ttt: Milli-second (000～999)
Latitude of image
Img_ImageSceneCenterLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene center
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of image
Img_ImageSceneCenterLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene center
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of image
Img_ImageSceneLeftTopLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of image
Img_ImageSceneLeftTopLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of image
Img_ImageSceneRightTopLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of image
Img_ImageSceneRightTopLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of image
Img_ImageSceneLeftBottomLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.

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29
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36
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40
41

SectionImage
information(Img)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (5/8)
Item name
KeywordValue
Longitude of image
Img_ImageSceneLeftBottomLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of image
Img_ImageSceneRightBottomLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of image
Img_ImageSceneRightBottomLongitude '-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of frame
Img_FrameSceneCenterLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene center
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of frame
Img_FrameSceneCenterLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene center
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of frame
Img_FrameSceneLeftTopLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of frame
Img_FrameSceneLeftTopLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of frame
Img_FrameSceneRightTopLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of frame
Img_FrameSceneRightTopLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Top
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of frame
Img_FrameSceneLeftBottomLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of frame
Img_FrameSceneLeftBottomLongitude'-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Left-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Latitude of frame
Img_FrameSceneRightBottomLatitude'-90.000'～'90.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Longitude of frame
Img_FrameSceneRightBottomLongitude '-179.999'～'180.000' [degree] (specify only for level 1.5/3.1 product)
scene Right-Bottom
Third decimal places are not omissible. Zero and positive number have no sign.
Off-nadir angle
Img_OffNadirAngle
NN.N [degree]

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43

44

45

Section
Product
information(Pdi)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (6/8)
Item name
KeywordValue
Data size of productPdi_ProductDataSize
unit: Mbytes = 1024Kbyte
Rounded off by the 2nd place of a decimal point. The first place of a decimal is notomissible.
Number of files in level
Pdi_CntOfL11ProductFileName Spotlight mode: 2 files
1.1/1.5/3.1 product
Pdi_CntOfL15ProductFileName High-sensitive/Fine modes (Single pol.) : 2 files
Pdi_CntOfL31ProductFileName
High-sensitive/Fine modes (Dual pol.) : 4 files
ScanSAR mode (Single pol.): 2 files
ScanSAR mode (Dual pol.): 4 files
High-sensitive/Fine modes (Full (Quad.) pol.): 8 files
Filename of level
Pdi_L11ProductFileNamenn
GeoTIFF file
1.1/1.5/3.1 productPdi_L15ProductFileNamenn‘IMG-XX-SSSSSSSSSSSSSSSSSSSSS- PPPPPPPPPP.tif’
Pdi_L31ProductFileNamenn
LUT file
nn: 01～99‘LUT-XX-SSSSSSSSSSSSSSSSSSSSS- PPPPPPPPPP.txt’
SSSSSSSSSSSSSSSSSSSSS : Scene ID
PPPPPPPPPP: Product ID
XX: Polarization (HH, HV, VH, VV)(in order of Tx-Rx)
Bits per pixel
Pdi_BitPixel'NN'
16: Level 1.5/3.1 (specify only for level 1.5/3.1 product)

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57

Section
Product
information(Pdi)
Result of auto
check
(Ach)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (7/8)
Item name
KeywordValue
Number of pixels
Pdi_NoOfPixels_0'0' - '99999' (Zero-suppressible)
Same as “ImageWidth” of Common TIFF-tags in All Processing Levels.
Number of lines
Pdi_NoOfLines_0'0' - '99999' (Zero-suppressible)
Same as “ImageLength” of Common TIFF-tags in All Processing Levels.
Product format
Pdi_ProductFormat'GeoTIFF' (fixed value)
Checking result of
Ach_TimeCheck'GOOD' / 'POOR'
Time data
GOOD: All lines are GPS-aligned, POOR: other than GOOD
Checking result of
Ach_AttitudeCheck'GOOD' / 'POOR'
attitude data
GOOD: other than POOR. POOR: There are two or more lines which the postureand the rate are not converging.
Status of absolute
Ach_AbsoluteNavigationStatus blanknavigation
Checking result of
Ach_HouseKeepingDataCheck'GOOD' / 'FAIR'
house keeping data
FAIR: There are one or more FAIR(s) among check items.
Checking result of
Ach_OrbitCheck'GOOD' / 'FAIR'
orbit data
GOOD: All values are normal. FAIR: All abnormal values are interpolated correctly.
Checking result of
Ach_OnBoardAttitudeCheck'GOOD' / 'FAIR'
on-board attitude data
GOOD: All values are normal. FAIR: All abnormal values are interpolated correctly.
Loss lines
Ach_LossLines'GOOD' / 'FAIR' / 'POOR'
GOOD: There is no loss line. FAIR: Number of loss line is 1 or more, but is not
more than threshold value. POOR: Number of loss line is more than threshold value.
Absolute navigation
Ach_AbsoluteNavigationTime
blank
time
Checking result of
Ach_PRF_Checkblank
PRF change

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SectionResult of auto
check
(Ach)
Resultinformation(Rad)
Label information(Lbi)

Table 4.3-1 Summary information for GeoTIFF Level 1.1/1.5/3.1 product (8/8)
Item name
Keyword
Value
Checking result of
Ach_CalibrationDataCheckblankcalibration data
Practice result code

Rad_PracticeResultCode'GOOD' / 'FAIR'
GOOD: normal FAIR: A product can be created by interpolating

Satellite nameSensor name
Processing level
Processing facility

Lbi_Satellite
Lbi_Sensor
Lbi_ProcessLevel
Lbi_ProcessFacility

Observation date

Lbi_ObservationDate'ALOS2' (fixed value)'SAR' (fixed value)'1.1' / '1.5' / '3.1''SCMO' / 'EICS'SCMO : Spacecraft Control Mission Operation system
EICS : Earth Intelligence Collection and Shearing System'YYYYMMDD'YYYYMMDD : (YYYY: year, MM: month, DD: day)

25

APALSAR-2
Level 2.1 GeoTIFF ProductFormat Description

Japan Aerospace Exploration Agency

ALOS-2 Product Format Description
GeoTIFF Level 2.1 Revision History (1/2)
Rev.

Date

Revision ContentsNC

2012/12/28

First EditionA

2014/5/16

p.5
3.1.1 Common TIFF tag
Revised description.
Before:3.1.1 Common TIFF Tag
Some TIFF-tags common to all processing levels are......
After:
3.1.1 TIFF Tag
TIFF-tags of level 2.1 product are....
p.6, p.7
Revised the title name.
Before: Common TIFF-tags in All Processing Levels
After: TIFF-tags of Level 2.1 Productp.6
Table 3-1 Common TIFF-tags in All Processing Levels(1/2)
Revised tag type of ’Image Width’ and ‘Image Length’.
Before: LONG
After: SHORT or LONG
p.7
Table 3-1 Common TIFF-tags in All Processing Levels(2/2)
Revised remark of ‘Orientation’.
Before: 3 = row: Bottom to Top, column: Left to Right4 = row: Bottom to Top,

column: Right to Left

After: 3 = row: Bottom to Top, column: Right to Left
4 = row: Bottom to Top,

column: Left to Right

RemarkALOS-2 Product Format Description
GeoTIFF Level 2.1 Revision History (2/2)
Rev.
A
Cont.

Date

Revision Contents

Remark

p.14-23
4.3. File Format of Summary Information
Revised description.
Before:Referredto“ALOS-2

Product

FormatDescription (CEOS Level 2.1)”
After: Added following contents
4.3.1 Format Definition of Keyword
4.3.2 Format Definition of Value
4.3.3 Contents of Summary Information
Added “Table 4-1 Summary information for GeoTIFF
Level 2.1 product”.
Changed ‘Number of files in level 2.1 product’,‘Filename of level 2.1 product’, and ‘Product format’ inthe table to correspond to summary information for
GeoTIFF Level 2.1 product.

ALOS-2 Product Format Description(GeoTIFF Level 2.1)
Table of Contents
1. Overview ...........................................................................................................................................1
2. Product Specifications ......................................................................................................................2
2.1. Outline of GeoTIFF Standard ....................................................................................................2
2.2. Composition of Product .............................................................................................................2
2.3. Filename .....................................................................................................................................3
3. Format ...............................................................................................................................................5
3.1. GeoTIFF File .............................................................................................................................5
3.1.1. Common TIFF Tag ..............................................................................................................5
3.1.2. GeoTIFF tag of level 2.1 Product .......................................................................................8
3.2. Look Up Table .........................................................................................................................13
4. Summary Information .....................................................................................................................144.1. Outline of Summary Information .............................................................................................144.2. Filename of Summary Information ..........................................................................................144.3. File Format of Summary Information ......................................................................................144.3.1. Format Definition of Keyword .........................................................................................144.3.2. Format Definition of Value ...............................................................................................144.3.3. Contents of Summary Information....................................................................................15i1. Overview
This document describes the format specifications for ALOS-2 GeoTIFF Level 2.1 products
which are generated with ALOS-2 Data Processing System.

12. Product Specifications
2.1. Outline of GeoTIFF Standard
GeoTIFF is a metadata standard, which allows geometric information to be embedded within
Aldus-Adobe’s raster Tagged Image File Format (TIFF) file.
2.2. Composition of Product
ALOS-2 GeoTIFF product is generated from ALOS-2 Level 2.1 processed data. GeoTIFF productcontains some pairs of GeoTIFF files and LUT (Look-Up Table) files according to the number ofpolarizations. The LUT is required in order to convert each pixel value (integer) into a
Sigma-Naught value (Real). Figure 2-1 shows a block diagram of GeoTIFF product. Table 2-1
shows the number of GeoTIFF/LUT files in each observation mode.

GeoTIFF Product

1…4

1…4

GeoTIFF File

LUT

Figure 2-1 Block Diagram of GeoTIFF Product

Table 2-1 Relationship between Number of GeoTIFF/LUT Files and Observation Mode
Observation mode

SingleDual

Full (Quad)

GeoTIFF

1

2

4

LUT

1

2

4

(Number of Polarizations)22.3. Filename
The filename definition of GeoTIFF product is shown in Table 2-2.
Table 2-2 Filename Definition of ALOS-2 GeoTIFF ProductFile TypeDefinition of Filename
IMG-XX- Scene ID

GeoTIFF-Product ID.tif
LUT-XX- Scene ID

LUT
Scene ID

-Product ID.txt

Contents
The file of GeoTIFF form. An integer value isindicated to each pixel. Geographic information andmap projection are indicated to the header.
The text file which summarizes the conversion
factor for changing each pixel value (integer) of a
GeoTIFF file into a Sigma Naught value (real).

= AAAAABBBBBCCCC-YYMMDDAAAAA : Satellite ID = 'ALOS2'BBBBB: Orbit accumulation number of a scene center

CCCC: Scene frame number of a scene center-: Separator (hyphen)

YYMMDD : Observation date of a scene center(YY: lower 2 figures of a year, MM: month, DD: day)
Product ID = DDDEFFFGHI
DDD: Observation Mode
SBS : Spotlight mode
UBS : Ultra-fine mode Single polarization
UBD : Ultra-fine mode Dual polarization
HBS : High-sensitive mode Single polarization
HBD : High-sensitive mode Dual polarization
HBQ : High-sensitive mode Full (Quad.) polarimetry
FBS : Fine mode Single polarization
FBD : Fine mode Dual polarization
FBQ : Fine mode Full (Quad.) polarimetry
WBS : ScanSAR nominal [14MHz] mode Single polarization
WBD : ScanSAR nominal [14MHz] mode Dual polarization
WWS: ScanSAR nominal [28MHz] mode Single polarization
WWD: ScanSAR nominal [28MHz] mode Dual polarization
VBS : ScanSAR wide mode Single polarization
VBD : ScanSAR wide mode Dual polarization

E: Observation Direction
L: Left looking, R: Right looking

FFF: Processing Level
2.1: Level 2.1
3

G: Processing Option
G: Geo-Coded onlyH

: Map Projection
U: UTM, P: PS, M: MER, L: LCC

I: Orbit Direction
A: Ascending, D: Descending

Polarization (Transmission and Receiving) = XX
HH

: Horizontally polarized wave transmission / Horizontally polarized wave receiving

HV :Horizontally polarized wave transmission / Vertically polarized wave receiving
VH:Vertically polarized wave transmission / Horizontally polarized wave receiving

VV : Vertically polarized wave transmission / Vertically polarized wave receiving

43. Format
3.1. GeoTIFF File
GeoTIFF is a metadata standard which allows geometric information to be embedded within a
TIFF image file. In ALOS-2 GeoTIFF products, GeoTIFF files are generated in TIFF-Strip format,
and some GeoTIFF-tags (identifiers) are different in each processing level. All TIFF files and
GeoTIFF-tags are based on TIFF Revision 6.0 and GeoTIFF Revision 1.0 standard, and image data
is recorded in little endian.
Since TIFF format supports 4 GB image size in maximum, the image which exceeds 4 GB isstored in BigTIFF format.
A

3.1.1. Common TIFF Tag
TIFF-tags of level 2.1 product are shown in Table 3-1.

5

Tag nameImageWidth

Table 3-1 TIFF-tags of Level 2.1 Product (1/2)
Description
Number of pixels in one line.

BitsPerSample

Tag type
SHORT orLONG
SHORT or
LONG
SHORT

Compression

SHORT

PhotometricInterpretation

SHORT

Color space type of bitmap image data
= 1 (fixed value)

ImageDescription

ASCII

Polarization of Tx and Rx= 'HH', 'HV', 'VH', 'VV'

ImageLengthA
RemarkNumber of lines.
Number of bits in one sample
L2.1 = 16 (fixed value)Compression type = 1 (fixed value)

6

L2.1: 16bit (absolute value)
1 = No compression
2 = ITU-T modified Huffman RLE
3 = ITU-T Group 3 fax encoding
4 = ITU-T Group 4 fax encoding
5 = LZW (fixed-length) compression
6 = JPEG compression (old style)
7 = JPEG compression (new style)
8 = ZIP compression
32773 = Packbits compression
0 = WhiteIsZero(Pixel value: White=0, Black =(2^BitsPerSample-1))
1 = BlackIsZero(Pixel value: Black=0, White=(2^BitsPerSample-1))
2 = RGB direct color(min=0 as black, max=(2^BitsPerSample-1) as white)
3 = Palette color(min=0, max=(2^BitsPerSample-1))
4 = Transparency Mask (definition of masked region)
In order of Tx and Rx

ATag name
Orientation

Tag type
SHORT

SamplesPerPixel

SHORT

PlanarConfiguration

SHORT

SampleFormat

Array of
SHORT

Table 3-1 TIFF-tags of Level 2.1 Product (2/2)
Description
RemarkOrientation of image = 1 (fixed value)
1 = row: Top to Bottom, column: Left to Right2 = row: Top to Bottom, column: Right to Left
3 = row: Bottom to Top, column: Right to Left
4 = row: Bottom to Top, column: Left to Right
5 = row: Left to Right, column: Top to Bottom
6 = row: Right to Left, column: Top to Bottom
7 = row: Right to Left, column: Bottom to Top
8 = row: Left to Right, column: Bottom to Top
Number of samples in one pixel
L2.1: 1 (absolute value)
L2.1 = 1 (fixed value)
Storing order of the data = 1 (fixed value)
1 = Chunky format: The component values for each pixel are
stored contiguously.
2 = Planar format: The components are stored in separate
components.
Type of data
1 = unsigned integer
L2.1 = 1 (fixed value)
2 = signed integer
3 = float
4 = undefined
5 = complex integer
6 = complex float
The number of elements of the array is equal to the value of“SamplePerPixel” tag

7

A

A

3.1.2. GeoTIFF tag of level 2.1 Product
GeoTIFF tags of ALOS-2 Level 2.1 GeoTIFF product are shown in Table 3-2.

8

Tag name
GTCitationGeoKey

Tag type
ASCII

GeogLinearUnitsGeoKey
GeogAngularUnitsGeoKey
ProjLinearUnitsGeoKey
GeogPrimeMeridianGeoKey
ModelPixelScaleTag

SHORT
SHORT
SHORT
SHORT
DOUBLE

ModelTiepointTag

DOUBLE

ModelTransformationTag

DOUBLE

Table 3-2 GeoTIFF-tags of Level 2.1 Product (1/4)
Description
RemarkProcessing option
Geo-coded= 'Geo-coded'
Coordinates unit (length) = 9001 (fixed value)
9001 = Linear_Meter[m]Coordinates unit (angle) = 9102 (fixed value)
9102 = Angular_Degree[deg]Projection coordinates unit (length) = 9001 (fixed value)
9001 = Linear_Meter[m]The position of the standard meridian line = 8901 (fixed value)
8901 = PM_Greenwich (Greenwich meridian)
The size of a pixel = (pixel width, line width, 0.0)
Units of width are as same as “GeogLinearUnitsGeoKey”
and “ProjLinearUnitsGeoKey”. [m]Correspondence of pixel-line coordinates and map coordinates.
(Pixel no., Line no, 0.0, Map-addr. X, Map-addr. Y, 0,0)=(0.5,
0.5, 0.0, Map-addr. X, Map-addr. Y, 0,0)The conversion matrix from a pixel and line coordinates to map When (pixel no., line no.) = (P, L);
coordinates
Map address X = a * P + b * L + d= (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p)
Map address Y = e * P + f * L + h
In a two-dimensional coordinate plane,
Map address X
a b 0 dPixel no.
Map address Y
e f 0 hLine no.
=0
0 0 0 001
0 0 0 11
= (a, b, 0, d, e, f, 0, g, 0, 0, 0, 0, 0, 0, 0, 1)

9Tag name
GTModelTypeGeoKey

Tag type
SHORTGTRasterTypeGeoKey

SHORT

Table 3-2 GeoTIFF-tags of Level 2.1 Product (2/4)
Description
RemarkCoordinate system type = 1 (fixed value)
1 = ModelTypeProjected (Projection Coordinate System)
2 = ModelTypeGeographic(Geographic Latitude-Longitude System)
3 = ModelTypeGeocentric(Geocentric (X,Y,Z) Coordinate System)
Alignment of pixel value = 1 (fixed value)
1 = PixelIsArea
The first pixel applies the domain surrounded by (0, 0), (0, 1), (1, 0), and(1, 1). The center of pixel is located in (0.5, 0.5).
2 = PixelIsPoint
The first pixel applies the domain surrounded by (-0.5,-0.5), (0.5,-0.5), (-0.5,0.5), (0.5, 0.5). The center of pixel is located in (0,0).
1)

0

0.5

1

2)

-0.5

0

0.5

-0.5
0
0
0.5
0.5
1
1

GeogGeodeticDatumGeoKey

SHORT

GeogEllipsoidGeoKey
ProjectedCSTypeGeoKey

SHORT
SHORT

Geographic coordinate system = 6655(fixedvalue)
Ellipsoid code = 7019 (fixed value)
Map projection code
User defined = 32767 (fixed value)

106655 = The International Terrestrial Reference Frame 1997(ITRF97)
7019 = Ellipse_GRS_1980(GRS80)
In all the projection system, the value “User defined” is set

1

Table 3-2 GeoTIFF-tags of Level 2.1 Product (3/4)
Description
RemarkMap projection code
In a case of other than UTM, the value “User defined” is
UTM projection
set.
Northern Hemisphere = 16000 + Zone no.
Southern Hemisphere = 16100 + Zone no.
PS / MER / LCC projection
User defined = 32767 (fixed value)
GeographicTypeGeoKey
SHORT
Map coordinate code = 4338 (fixed value)
4338 = ITRF97
GeogCitationGeoKey
ASCII
Specify a geographic coordinate system, an ellipsoid model,
and a map projection system.
= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=UTM'= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=PS'= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=MER'= 'Datum=ITRF97 Ellipsoid=GRS80 Projection=LCC'
The following tag is specified only when “ProjectionGeoKey” is set as “user defined” (32767)
ProjCoordTransGeoKey
SHORT
Map projection code
PS projection
PS projection = 15 (fixed value)
15 = CT_PolarStereographic
MER projection = 7 (fixed value)
MER projection
LCC projection = 8 (fixed value)
7 = CT_Mercator
LCC projection
8 = CT_LambertConfConic_2SP
On the following tags, only the parameter needed in the selected map projection is specified.
ProjNatOriginLongGeoKey
DOUBLE Longitude of the map-projection natural origin
The unit specified in “GeogAngularUnitsGeoKey” is used
In UTM and PS projection:[deg].
The map-projection natural origin of UTM and PS
Center longitude of projection is specified
projection is specified in “ProjFalseEastingGeoKey”.
In MER and LCC
The natural origin of northern hemisphere corresponds to
The longitude of the map starting point is specified.
negative value of map coordinate y, and that of southernhemisphere, positive value, in the case of PS projection.
ProjNatOriginLatGeoKey
DOUBLE Latitude of the map-projection natural origin
The unit specified in “GeogAngularUnitsGeoKey” is used
In UTM and PS projection:[deg].
The center latitude of projection is specified
The map-projection natural origin of UTM and PS
In MER and LCC
projection is specified in ”ProjFalseNorthingGeoKey”.
The latitude of the map starting point is specified.
Tag name
ProjectionGeoKey

Tag type
SHORT

11Table 3-2 GeoTIFF-tags of Level 2.1 Product (4/4)
Tag name
Tag type
Description
RemarkOn the following tags, only the parameter needed in the selected map projection is specified.
ProjFalseEastingGeoKey
DOUBLE The easting value from the map-projection natural origin (to The unit specified in “ProjLinearUnitsGeoKey” is used
determine the map natural origin).
[m]
It is specified only in the case of UTM projection.
= 500000.0 (fixed value)
ProjFalseNorthingGeoKey
DOUBLE The northing value from the map-projection natural origin The unit specified in “ProjLinearUnitsGeoKey” is used
(to determine the map natural origin).
[m]
It is specified only in the case of UTM projection.
Northern Hemisphere = 0 (fixed value)
Southern Hemisphere = 10000000.0 (fixed value)
ProjStdParallel1GeoKey
DOUBLE Latitude of primary standard parallel.
The unit specified in “GeogAngularUnitsGeoKey” is used
It is specified only in the case of LCC projection[deg]
ProjStdParallel2GeoKey
DOUBLE Latitude of second standard parallel.
The unit specified in “GeogAngularUnitsGeoKey” is used
It is specified only in the case of LCC projection[deg]
ProjScaleAtNatOriginGeoKey DOUBLE Scale at natural origin
non-dimension
It is specified only in the case of UTM and PS projection.
UTM = 0.9996 (fixed value)
PS = 1.0 (fixed value)123.2. Look Up Table
The LUT is the text file which records the conversion factor for converting from the integer value
stored in each pixel of a GeoTIFF file into a real value ( σ 0 : Sigma Naught). The conversion
equation for the level 2.1 is shown below.
• Level 2.1

σ0 =(M + B )2

A

Here, M is pixel value as unsigned integer. A is the coefficient which only depends on range
direction. B is an offset value and is common to all the pixels.
An example of LUT file is shown in Table 3-3. Here, N is the number of pixels in one line.
Table 3-3 Example of LUT format
Line 1

offset value B

Line 2

scaling factor A[0]Line 3

scaling factor A [1]

...

...

Line (N+1)

scaling factor A [N-1]

However, all A is the same value in the geocoded product of the level 2.1.
A [dB] value () is converted by using following formula:13

4. Summary Information
The summary information on GeoTIFF level 2.1 is shown in below.
4.1. Outline of Summary Information
The summary information file includes the information for creating processed data created at
ALOS-2 Data Processing System, and it is always made in a pair with its processed data.
4.2. Filename of Summary Information
The filename of summary information is fixed as follows.
summary.txt
4.3. File Format of Summary Information
The summary information file consists of some record lines which use LF (line feed code) as atermination, and does not include header information, footer information, etc. A record line consistsof a keyword, a equal mark (=), and a value. A summary information file format outline is shown in
Figure 4-1.
Keyword…
Keyword

=
…
=

Value
…
Value

LF
…
LF

Figure 4-1 Outline of Summary Information File Format
4.3.1. Format Definition of Keyword(1)

The keyword is stored from the head of a record line.

(2)

The equal mark ‘=’ is stored after the keyword.

(3)

There is no blank character between a keyword and ‘=’, in principle.

4.3.2. Format Definition of Value(1)

The value is a text string bundled with double quotation letters (“).

(2)

The value can contain alphabets, digits, and some special characters (except for double
quotation). Numerical values are also stored as an ASCII string.

(3)

There is no blank character between ‘=’ and the former double quotation letter, in principle.

14A

4.3.3. Contents of Summary InformationA

The items of the GeoTIFF Level 2.1 summary information are described in Table 4-1. "b" in atable means blanks.

15

Table 4-1 Summary information for GeoTIFF Level 2.1 product (1/8)
Section
Ordering
information(Odi)

Item name
Scene description ID

Keyword
Odi_SceneId

Processed
Site/Date/Time

Odi_SiteDateTime

Value
ID for specifying a scene uniquely'AAAAAAAAAAAAAAAA-NNNNN-xxx-nnn'
AAAAAAAAAAAAAAAA: Operation Segment No
NNNNN: Observation ID
xxx: 001～999
nnn: Scene no.
Spacecraft Control Mission Operation system='PROCESS: JAPAN-JAXA-ALOS2-SCMObbYYYYMMDDbHHMMSS'
Earth Intelligence Collection and Shearing System= 'PROCESS: JAPAN-JAXA-ALOS2-EICSbbYYYYMMDDbHHMMSS'YYYYMMDD : Processed date (YYYY:
HHMMSS: Processed time (UTC)
Scene specification(Scs)

Scene ID

Scs_SceneID

Amount of scene shift

Scs_SceneShiftyear, MM: month, DD: day)

'AAAAABBBBBCCCC-YYMMDD'AAAAA : Satellite name (='ALOS2')BBBBB : Orbit accumulation number of a scene center
CCCC : Scene frame number of a scene center: separator (hyphen)
YYMMDD: Observation date of scene center (YY: lower 2 figures of a year, MM:month, DD: day)'-5'～'4' : Except ScanSAR mode'-25'～'20' : ScanSAR mode
Zero and positive number have no sign.

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ATable 4-1 Summary information for GeoTIFF Level 2.1 product (2/8)
Section
Product
specification(Pds)

Item nameProduct ID

Keyword
Pds_ProductID

Resampling method

Pds_ResamplingMethod

UTM zone no.

Pds_UTM_ZoneNo

Value'DDDEFFFGHI'
DDD: Observation mode (*)
SBS: Spotlight mode (Single pol.)UBS: Ultra-Fine mode (Single pol.)UBD: Ultra-Fine mode (Dual pol.)
HBS: High-sensitive mode (Single pol.)
HBD: High-sensitive mode (Dual pol.)
HBQ: High-sensitive mode (Full (Quad.) pol.)FBS: Fine mode (Single pol.)FBD: Fine mode (Dual pol.)FBQ: Fine mode (Full (Quad.) pol.)
WBS: ScanSAR nominal [14MHz] mode (Single pol.)
WBD: ScanSAR nominal [14MHz] mode (Dual pol.)WWS: ScanSAR nominal [28MHz] mode (Single pol.)
WWD: ScanSAR nominal [28MHz] mode (Dual pol.)
VBS: ScanSAR wide mode (Single pol.)VBD: ScanSAR wide mode (Dual pol.)E : Observation direction (*)
L: Left looking, R: Right looking
FFF: Processing level2.1: Level 2.1
G : Processing option
G: Geo-Coded
H : Map projection type
U: UTM, P: PS, M: MER, L: LCC
I : Orbit direction (*)
A: Ascending, D: Descending'NN' / 'BL' / 'CC'
Nearest Neighbor / Bi-Linear / Cubic Convolution'1'～'60' (specify only for UTM projected product)

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Table 4-1 Summary information for GeoTIFF Level 2.1 product (3/8)
Section
Product
specification(Pds)

Item name
PS reference latitude

Keyword
Pds_PS_ReferenceLatitude

PS reference longitude

Pds_PS_ReferenceLongitude

LCC reference
latitudinal line 1
LCC reference
latitudinal line 2
Map direction
LCC origin latitude

Pds_LCC_ReferenceLatitud
inalLine1
Pds_LCC_ReferenceLatitud
inalLine2
Pds_MapDirection
Pds_LCC_OriginLatitude

LCC origin longitude

Pds_LCC_OriginLongitude

Pixel spacing

Pds_PixelSpacing

Precision of orbit data

Pds_OrbitDataPrecision

Precision of attitude data

Pds_AttitudeDataPrecision

Digital Elevation Model

Pds_DigitalElevationModel

Geoid Model

Pds_GeoidModel

Value
Northern Hemisphere: ’25.000 <= reference latitude <='90.000'
Southern Hemisphere: '-90.000' <= reference latitude <= ‘-25.000’(specify only for PS projected product)'-179.999' ≤ reference longitude ≤ '180.000'(specify only for PS projected product)'-90.000' < reference latitude < '90.000'(specify only for LCC projected product)'-90.000' < reference latitude < '90.000'(specify only for LCC projected product)'MapNorth''-90.000' ≤ origin latitude ≤ '90.000'(specify only for LCC projected product)'-179.999' ≤ origin longitude ≤ '180.000'(specify only for LCC projected product)
Spotlight mode: ‘0.625’/’1.25’/’2.5’ [m]Ultra-Fine mode: ‘2.5’/’5.0’/’10.0’ [m]High-sensitive mode: ‘3.125’/’6.25’/’12.5’ [m]Fine beam mode: ‘6.25’/’12.5’ [m]ScanSAR mode: ’25.0’/’50.0’/’100.0’ [m]'Precision' / ' Onboard ' / 'RARR_Predict'
Precision: High precision orbit information
Onboard: Onboard orbit determination
RARR_Predict : Predicted orbit information'Onboard'
Onboard : Onboard attitude determination‘GISMAP_Terrain’/’SRTM90m_v4.1’
GISMAP_Terrain: GIS MAP Terrain (Hokkaido-Chizu Company Ltd.)SRTM90m_v4.1: SRTM 90m Digital Elevation Database v4.1 (CSI)‘GSIGEO2000’/’EGM96’
GSIGEO2000: Japanese Geoid Model (Geospatial Information Authority of Japan)
EGM96: Earth Gravitational Model 1996 (NGA)

18

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Table 4-1 Summary information for GeoTIFF Level 2.1 product (4/8)
SectionImage information(Img)

Item nameDate and time of scene
center

Keyword
Img_SceneCenterDateTime

Date and time of scene
start

Img_SceneStartDateTime

Date and time of scene
end
Latitude of image scene
centerLongitude of image
scene center
Latitude of image scene
Left-Top
Longitude of image
scene Left-Top
Latitude of image scene
Right-Top
Longitude of image
scene Right-Top
Latitude of image scene
Left-Bottom
Longitude of image
scene Left-Bottom
Latitude of image scene
Right-Bottom
Longitude of image
scene Right-Bottom

Img_SceneEndDateTime
Img_ImageSceneCenterLati
tude
Img_ImageSceneCenterLon
gitudeImg_ImageSceneLeftTopLa
titudeImg_ImageSceneLeftTopLo
ngitudeImg_ImageSceneRightTop
Latitude
Img_ImageSceneRightTop
Longitude
Img_ImageSceneLeftBotto
mLatitude
Img_ImageSceneLeftBotto
mLongitude
Img_ImageSceneRightBott
omLatitude
Img_ImageSceneRightBott
omLongitude

Value'YYYYMMDDbhh: mm: ss.ttt'(UT)YYYY : Year (A.D.)
MM : Month (01～12)
DD : Day (01～31)
hh: Hour (00～23)mm : Minute (00～59)
ss: Second (00～60) (ss=60 is used only by a leap second.)
ttt: Milli-second (000～999)'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.

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ATable 4-1 Summary information for GeoTIFF Level 2.1 product (5/8)
SectionImage information(Img)

Item nameLatitude of frame scene
centerLongitude of frame
scene center
Latitude of frame scene
Left-Top
Longitude of frame
scene Left-Top
Latitude of frame scene
Right-Top
Longitude of frame
scene Right-Top
Latitude of frame scene
Left-Bottom
Longitude of frame
scene Left-Bottom
Latitude of frame scene
Right-Bottom
Longitude of frame
scene Right-Bottom
Off-nadir angle

Keyword
Img_FrameSceneCenterLati
tude
Img_FrameSceneCenterLon
gitudeImg_FrameSceneLeftTopLa
titudeImg_FrameSceneLeftTopLo
ngitudeImg_FrameSceneRightTop
Latitude
Img_FrameSceneRightTop
Longitude
Img_FrameSceneLeftBotto
mLatitude
Img_FrameSceneLeftBotto
mLongitude
Img_FrameSceneRightBott
omLatitude
Img_FrameSceneRightBott
omLongitude
Img_OffNadirAngle

Value'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-90.000'～'90.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
'-179.999'～'180.000' [degree]
Third decimal places are not omissible. Zero and positive number have no sign.
NN.N [degree]

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ATable 4-1 Summary information for GeoTIFF Level 2.1 product (6/8)
Section
Product
information(Pdi)

Item name
Data size of productKeyword
Pdi_ProductDataSize

Number of files in level2.1 product

Pdi_CntOfL21ProductFileN
ame

Filename of level 2.1
product

Pdi_L21ProductFileNamennnn: 01～99

Bits per pixel

Pdi_BitPixel

Number of pixels

Pdi_NoOfPixels_0

Number of lines

Pdi_NoOfLines_0

Product format

Pdi_ProductFormat

Value
unit: Mbyte = 1024Kbyte
Rounded off by the 2nd place of a decimal point. The first place of a decimal is notomissible.
Spotlight mode: 2 files
High resolution mode (Single pol.) : 2 files
High resolution mode (Dual pol.) : 4 files
ScanSAR mode (Single pol.) : 2 files
ScanSAR mode (Dual pol.) : 4 files
High resolution mode (Full (Quad.) pol.) : 8 files
GeoTIFF file
'IMG-XX-SSSSSSSSSSSSSSSSSSSSS-PPPPPPPPPP.tif'
LUT file'LUT-XX-SSSSSSSSSSSSSSSSSSSSS-PPPPPPPPPP.txt'
SSSSSSSSSSSSSSSSSSSSS : Scene ID
PPPPPPPPPP: Product ID
XX: Polarization (HH, HV, VH, VV)(in order of Tx-Rx)'NN'
16: (fixed value)'0' - '99999' (Zero-suppressible)
The number of pixels of the SAR signal data in processed data record (prefix is notincluded).
'0' - '99999' (Zero-suppressible)
The number of lines of the SAR signal data in processed data record (file descriptor
is not included).
'GeoTIFF '21

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Table 4-1 Summary information for GeoTIFF Level 2.1 product (7/8)
SectionResult
check
(Ach)

of

auto

Item name
Checking result of time
data
Checking result of
attitude data

Keyword
Ach_TimeCheck

Status of absolutenavigation
Checking result ofhouse keeping data
Checking result of orbit
data

Ach_AbsoluteNavigationStatus

Checking result of
on-board attitude data

Ach_OnBoardAttitudeCheck

Loss lines

Ach_LossLines

Absolute navigation
time
Checking result of PRF
changeChecking result of
calibration data

Ach_AbsoluteNavigationTime'GOOD' / 'FAIR'
FAIR: There are one or more FAIR(s) among check items.
'GOOD' / 'FAIR'
GOOD: All values are normal. FAIR: All abnormal values are interpolated
correctly.
'GOOD' / 'FAIR'
GOOD: All values are normal. FAIR: All abnormal values are interpolated
correctly.
'GOOD' / 'FAIR' / 'POOR'
GOOD: There is no loss line. FAIR: Number of loss line is 1 or more, but is
not more than threshold value. POOR: Number of loss line is more thanthreshold value.
blank

Ach_PRF_Checkblank

Ach_CalibrationDataCheckblank

Ach_AttitudeCheck

Ach_HouseKeepingDataCheck
Ach_OrbitCheck

Value'GOOD' / 'POOR'
GOOD: All lines are GPS-aligned, POOR: other than GOOD
'GOOD' / 'POOR'
GOOD: other than POOR. POOR: There are two or more lines which theposture and the rate are not converging.
‘OK’/’NG’

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ATable 4-1 Summary information for GeoTIFF Level 2.1 product (8/8)
SectionResult information(Rad)
Label information(Lbi)

Item namePractice result code

Keyword
Rad_PracticeResultCode

Value'GOOD'
GOOD: normal

Satellite name

Lbi_Satellite'ALOS2' (fixed value)Sensor name

Lbi_Sensor'SAR' (fixed value)

Processing level
Processing facility

Lbi_ProcessLevel
Lbi_ProcessFacility

Observation date

Lbi_ObservationDate'2.1''SCMO' / 'EICS'SCMO : Spacecraft Control Mission Operation system
EICS : Earth Intelligence Collection and Shearing System'YYYYMMDD'YYYYMMDD : (YYYY: year, MM: month, DD: day)

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A