U.S. Department of the Interior

U.S. Geological Survey

Geometric Assessment of Remote Sensed DataGeometric Assessment of Remote Sensed Data

Oct. 25 2005

Presented By:

Michael Choate, SAICU.S. Geological Survey, National Center for EROSSioux Falls, SD

2

Outline and IntroductionOutline and Introduction

Landsat 7 Image Assessment System (IAS) Background Expanding the use of IAS

Ground Control Mensuration RESOURCESAT-1 Assessment

Statistics Vector Plots

Conclusions

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Landsat Image Assessment System (1 of 2)Landsat Image Assessment System (1 of 2)

Responsible for assessment of image quality of Enhanced Thematic Mapper (ETM+)

Ensure compliance with radiometric and geometric requirements Perform radiometric and geometric calibration of satellite and

ETM+ Calibration results and updates distributed through Calibration

Parameter File (CPF) IAS contains Image to Image (I2I) registration assessment tool

Provides numerical evaluation of accuracy of common bands of temporally distinct ETM+ images

No real restriction on image data sets that can be used, other sensor can be used in assessment

IAS contains Band to Band (B2B) registration assessment tool Provides numerical evaluation of accuracy of between band

registration within an image No real restriction on image data sets that can be used, other

sensor can be used in assessment

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Landsat Image Assessment System (2 of 2)Landsat Image Assessment System (2 of 2)

Expanding the IAS beyond ETM+ LPGS-Lite used as prototype for Advanced Land Imager (ALI)

assessment system (ALIAS) IAS I2I and B2B used for assessment of other sensors and

datasets SurreySat Orbview-3 Digitized aerial photography

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Ground Control (1 of 2)Ground Control (1 of 2)

Landsat IAS built ground reference data sets called Geometric Supersites or just Supersites

Built from Digital Orthophoto Quadrangulars (DOQs) DOQs are designed to meet national mapping accuracy

standards of 1:24k maps, or ~6 meters Inspection with highly accurate GPS surveyed locations showed

most DOQs exceeded 6 meters accuracy 1 meter DOQs reduced in resolution to match PAN band (15m for

ETM+ and 10m for ALI) DOQs are mosaiced to create a data set equal to one World Wide

Reference 2 (WRS2) nominal swath/length Image chips are pulled from DOQ mosaics USGS 1 arc second DEMs used for ground control height

Currently 30 data sets available

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Ground Control (2 of 2)DOQ Mosaic

Ground Control (2 of 2)DOQ Mosaic

Note that individual DOQ files are visible in the mosaic

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Ground Control (3 of 3)Landsat WRS-2 Supersite Locations (CONUS)

Ground Control (3 of 3)Landsat WRS-2 Supersite Locations (CONUS)

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MensurationMensuration

Mensuration done with Grey Scale Correlation

• Offset is calculated by fitting surface around peak location

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CorrelationCorrelation

Grey Scale Correlation

CalculatePeak

X and YOffset

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RESOURCESAT-1 RESOURCESAT-1

Payload contains three imaging sensors Linear Imaging Self Scanner IV (LISS-IV)

Ground sample distance of 5.8 meters 3 bands 70km swath (monochromatic) 23km (multispectral)

Linear Imaging Self Scanner III (LISS-III) Ground sample distance of 23.5 meters 4 bands 141km swath

Advanced Wide Field Sensor (AWiFS) Two separate sensor modules (AWiFS-A and AWiFS-B) 4 bands 370km swath for each camera (740km total)

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RESOURCESAT-1 Assessment (1 of 2)RESOURCESAT-1 Assessment (1 of 2)

Attempt to assess both the AWiFS and LISS-III sensors aboard the RESOURCESAT-1 platform

Given two areas of coverage Arizona

Corresponds to Landsat WRS-2 path 37 row 37 Acquisition date 6/29/2005

Railroad Valley Corresponds to Landsat WRS-2 path 40 row 33 Acquisition date 8/10/2005

Both images were orthorectified geocoded products AWiFS Assessment

Image extent of AWiFS data set allowed only a very small portion of the image file to be compared to corresponding supersite

Issue made worse by comparing individual AWiFS data sets (A,B,C,D) independently

Independent study done to avoid double resampling AWiFS data sets (each data set map projected with different set of parameters)

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RESOURCESAT-1 Assessment (2-2)RESOURCESAT-1 Assessment (2-2)

Control covered only partial amount of multiple data sets Band assessment made for all data sets

AWiFS A, B, C and D data sets assessed independently LISS-III Assessment

DOQ control completely covered full image extent Output included

residuals file containing point by point residual offset in line and sample direction

statistical file containing maximum, minimum, mean, standard deviation, and root mean squared error of residuals for line and sample directions

residuals vector plot

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DOQ and LISS-III

AWiFS-A,B,C,D

Arizona Data Sets (AWiFS, LISS-III, DOQ)

DOQ

LISS-III

897000 m

85800 m 172000 m

172000 m

172000 m

172000 m

A B

CD

DOQ and LISS-III

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Full Resolution LISS-III to DOQFull Resolution LISS-III to DOQ

DOQLISS-III

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AWiFS Image-to-Image AWiFS Image-to-Image

Data Set Image Correlated Kept

Standard Deviation

Line

Standard Deviation Sample

RMSE Line

(pixels)

RMSE Sample (pixels)

RMSE Line

(meters)

RMSE Sample (meters)

Arizona C 139 104 0.1397 0.1077 0.2068 0.1317

11.580

7.375

Arizona A 78 55 0.3427 0.2201 0.7097 0.2286

39.743

12.801

Railroad Valley D 43 32 0.1063 0.2275 0.1344 0.3206

7.526

17.953

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AWiFS Band-to-band registrationArizona

AWiFS Band-to-band registrationArizona

Rband = Reference Sband = SearchStDevL = Standard deviation lineStDevS = Standarddeviation sampleRMSEL = Root mean squared errorlineRMSES = Rootmean squared errorsample

Rband Sband Correlated Kept StDevL StDevS RMSEL RMSES

AWIFSA 2 3 400 277 0.04226 0.04382 0.04382 0.06592 2 4 385 191 0.06595 0.08581 0.08403 0.08600 2 5 385 169 0.07565 0.08671 0.09238 0.11779 3 4 387 199 0.06837 0.06114 0.07558 0.07016 3 5 398 198 0.09356 0.08532 0.10121 0.15835 4 5 387 215 0.10925 0.11055 0.10963 0.15464

AWIFSB 2 3 382 239 0.03524 0.03407 0.05388 0.10192 2 4 375 189 0.06740 0.07265 0.12407 0.14688 2 5 376 242 0.10609 0.16076 0.21235 0.16775 3 4 371 178 0.03845 0.06093 0.07159 0.07729 3 5 383 244 0.07445 0.20019 0.14464 0.23672 4 5 376 246 0.12470 0.18588 0.15958 0.24792

AWIFSC 2 3 385 217 0.03390 0.04197 0.03736 0.05815 2 4 365 200 0.07396 0.08361 0.07957 0.08418 2 5 381 173 0.08964 0.10440 0.12030 0.15107 3 4 368 156 0.04472 0.04065 0.04508 0.05547 3 5 387 196 0.08591 0.11163 0.10627 0.19996 4 5 381 167 0.07336 0.11273 0.07985 0.13505

AWIFSD 2 3 385 269 0.03979 0.03624 0.06174 0.09626 2 4 376 220 0.06576 0.07917 0.12023 0.14688 2 5 384 254 0.09942 0.16939 0.22521 0.16939 3 4 376 206 0.05170 0.06046 0.07618 0.07560 3 5 385 280 0.08614 0.19413 0.17400 0.23242 4 5 380 214 0.10408 0.10795 0.14929 0.22538

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AWiFS Band-to-band registrationRailroad Valley

AWiFS Band-to-band registrationRailroad Valley

Rband Sband Correlated Kept StDevL StDevS RMSEL RMSES

AWIFSA 2 3 399 279 0.03602 0.04776 0.04135 0.07413

2 4 387 187 0.07630 0.08233 0.09105 0.08618

2 5 393 211 0.1122 0.12855 0.14919 0.15088

3 4 389 170 0.05387 0.06460 0.05547 0.07090

3 5 396 195 0.09002 0.13150 0.11036 0.21430

4 5 380 142 0.07946 0.09086 0.08373 0.16688 AWIFSB 2 3 377 259 0.03842 0.03672 0.04473 0.11329

2 4 359 181 0.06190 0.07686 0.09917 0.12965

2 5 372 234 0.12667 0.20486 0.19267 0.20619

3 4 359 153 0.03807 0.05668 0.06560 0.07051

3 5 371 226 0.10473 0.22581 0.14773 0.25554

4 5 362 218 0.14401 0.20931 0.16418 0.24253 AWIFSC 2 3 400 240 0.02833 0.03724 0.03397 0.06240

2 4 368 137 0.07316 0.03811 0.07659 0.04298

2 5 396 218 0.08465 0.10226 0.11299 0.15503

3 4 373 150 0.03658 0.04852 0.03651 0.06133

3 5 398 169 0.05943 0.08506 0.08081 0.20627

4 5 372 223 0.10425 0.18362 0.10639 0.18669 AWIFSD 2 3 383 204 0.03383 0.02352 0.03808 0.10849

2 4 380 227 0.05506 0.06319 0.09495 0.14275

2 5 381 260 0.09961 0.20816 0.17632 0.20891

3 4 380 223 0.05212 0.03589 0.07748 0.05903

3 5 381 284 0.10137 0.22873 0.15645 0.26241

4 5 379 280 0.11741 0.18018 0.13605 0.23520

Rband = Reference Sband = SearchStDevL = Standard deviation lineStDevS = Standarddeviation sampleRMSEL = Root mean squared errorlineRMSES = Rootmean squared errorsample

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LISS-III Image-to-ImageLISS-III Image-to-Image

Data Set

Correlated Kept

Standard Deviation

Line (pixels)

Standard Deviation Sample (pixels)

RMSE Line

(pixels)

RMSE Sample (pixels)

RMSE Line

(meters)

RMSE

Sample (meters)

Arizona 272 125 0.1556 0.1151 0.1586 0.1207 3.727 2.836 Railroad

Valley 342 199 0.1387 0.1239 0.1484 0.3871

3.487

9.096

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LISS-III Band-to-band registrationLISS-III Band-to-band registration

Rband Sband Correlated Kept StDevL StDevS RMSEL RMSES 2 3 395 273 0.08324 0.02066 0.16589 0.07507 2 4 393 241 0.06012 0.08167 0.08314 0.13762 2 5 394 256 0.09039 0.07859 0.09415 0.11794 3 4 394 200 0.04144 0.05549 0.12041 0.07635 3 5 394 237 0.04947 0.08265 0.12463 0.08754 4 5 392 174 0.06117 0.05555 0.06140 0.06184

Rband Sband Correlated Kept StDevL StDevS RMSEL RMSES 2 3 387 309 0.07114 0.02327 0.18845 0.05252 2 4 370 214 0.06762 0.08491 0.07830 0.14568 2 5 378 251 0.09012 0.06464 0.13489 0.11831 3 4 367 151 0.03944 0.06010 0.11135 0.08848 3 5 386 201 0.04210 0.04960 0.07953 0.07113 4 5 377 152 0.03947 0.10423 0.04325 0.10920

Arizona

Railroad Valley

Rband = Reference Sband = SearchStDevL = Standard deviation lineStDevS = Standarddeviation sampleRMSEL = Root mean squared errorlineRMSES = Rootmean squared errorsample

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LISS-III Band registration vector plot (Arizona)Vectors scaled to show trend

LISS-III Band registration vector plot (Arizona)Vectors scaled to show trend

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LISS-III Band registration vector plot (Railroad Valley)Vectors scaled to show trend

LISS-III Band registration vector plot (Railroad Valley)Vectors scaled to show trend

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LISS-III Image to Image Residuals (Arizona)Vectors scaled by 350

LISS-III Image to Image Residuals (Arizona)Vectors scaled by 350

LISS-III Arizona Data setVector residuals

comparing LISS-III to DOQs

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LISS-III Image to Image Residuals (Railroad Valley)Vectors scaled by 350

LISS-III Image to Image Residuals (Railroad Valley)Vectors scaled by 350

LISS-III Railroad Valley Data SetVector Residual

Comparing LISS-III and DOQs

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ConclusionsConclusions

Landat 7 Image Assessment System can be expanded for use beyond that of the Enhanced Thematic Mapper

Image extent of AWiFS data set difficult to assess with given ground control available

Approach using other type of control covering more area would work better

Mosaicing several Landsat scenes National Land Cover Database (NLCD)

AWiFS data set band registration difficult to assess, more data sets would be helpful

LISS-III data sets showed good relative geometric accuracy to that of DOQs

LISS-III vector plots for band registration residuals show possibility of small misalignment

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Back Up Slides

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LISS-III Band registration vector plot (Arizona)LISS-III Band registration vector plot (Arizona)

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AWiFS Railroad Valley Data Set Showing DOQ CoverageAWiFS Railroad Valley Data Set Showing DOQ Coverage

DOQ Coverage

Red out line is equal to approximately one Landsat WRS image extent

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LISS-III Railroad Valley Data Set Showing DOQ CoverageLISS-III Railroad Valley Data Set Showing DOQ Coverage

LISS-III DOQ Mosaic