I have hundreds of very large TIFFs which were georeferenced 15+ years ago using ArcGIS 9.2. Viewing them in ArcMap 9.2 the images are properly located and sized/warped on the map. However, they need to be warped to the final projection. The GCPs are embedded in the TIF and also in the tif.xml file.
While I can achieve warping to a final projected image using the Clip tool, it takes a long time for each image.
I've tried using GDAL warp utilities to do this, but am getting empty final images (all black).
eg:
`\OSGeo4W\bin\gdalwarp.exe -overwrite -co COMPRESS=DEFLATE IQALUIT_1948_A11535_043.tif out.tif`
`\OSGeo4W\bin\gdalwarp.exe -overwrite --config GDAL_GEOREF_SOURCES PAM -co COMPRESS=DEFLATE IQALUIT_1948_A11535_043.tif out.tif`
Here is the output from `\OSGeo4W\bin\gdalinfo.exe IQALUIT_1948_A11535_043.tif`:
```
Driver: GTiff/GeoTIFF
Files: IQALUIT_1948_A11535_043.tif
IQALUIT_1948_A11535_043.aux
IQALUIT_1948_A11535_043.rrd
IQALUIT_1948_A11535_043.tif.aux.xml
Size is 18565, 18492
GCP Projection =
PROJCRS["Canada_Lambert_Conformal_Conic",
BASEGEOGCRS["NAD83",
DATUM["North American Datum 1983",
ELLIPSOID["GRS 1980",6378137,298.257222101,
LENGTHUNIT["metre",1]],
ID["EPSG",6269]],
PRIMEM["Greenwich",0,
ANGLEUNIT["Degree",0.0174532925199433]]],
CONVERSION["unnamed",
METHOD["Lambert Conic Conformal (2SP)",
ID["EPSG",9802]],
PARAMETER["Latitude of false origin",40,
ANGLEUNIT["Degree",0.0174532925199433],
ID["EPSG",8821]],
PARAMETER["Longitude of false origin",-96,
ANGLEUNIT["Degree",0.0174532925199433],
ID["EPSG",8822]],
PARAMETER["Latitude of 1st standard parallel",50,
ANGLEUNIT["Degree",0.0174532925199433],
ID["EPSG",8823]],
PARAMETER["Latitude of 2nd standard parallel",70,
ANGLEUNIT["Degree",0.0174532925199433],
ID["EPSG",8824]],
PARAMETER["Easting at false origin",0,
LENGTHUNIT["metre",1],
ID["EPSG",8826]],
PARAMETER["Northing at false origin",0,
LENGTHUNIT["metre",1],
ID["EPSG",8827]]],
CS[Cartesian,2],
AXIS["(E)",east,
ORDER[1],
LENGTHUNIT["metre",1,
ID["EPSG",9001]]],
AXIS["(N)",north,
ORDER[2],
LENGTHUNIT["metre",1,
ID["EPSG",9001]]]]
Data axis to CRS axis mapping: 1,2
GCP[ 0]: Id=, Info=
(16.5886813769484,11.2421187314794) -> (1298609.77217853,2919147.39696529,0)
GCP[ 1]: Id=, Info=
(16.8939942179049,11.7402607351451) -> (1298500.0219128,2919153.17329506,0)
GCP[ 2]: Id=, Info=
(18.8921073940182,10.0052797183835) -> (1298631.40807544,2919617.77480046,0)
GCP[ 3]: Id=, Info=
(21.4572641379127,13.0572806764721) -> (1297892.90562009,2919783.3167529,0)
GCP[ 4]: Id=, Info=
(19.6528779424261,13.8720869249719) -> (1297910.23024105,2919417.7417536,0)
GCP[ 5]: Id=, Info=
(20.6880569996538,12.0845177405408) -> (1298127.44460173,2919739.01694754,0)
GCP[ 6]: Id=, Info=
(21.5855745124354,11.8220205578855) -> (1298091.07382506,2919911.77813673,0)
GCP[ 7]: Id=, Info=
(19.6699549399509,11.5899398962065) -> (1298297.65636365,2919614.6948765,0)
GCP[ 8]: Id=, Info=
(19.2596578670837,14.6946775183915) -> (1297815.43048519,2919292.29625073,0)
GCP[ 9]: Id=, Info=
(18.8790359460127,12.7118694177316) -> (1298182.37712172,2919377.79059004,0)
GCP[ 10]: Id=, Info=
(17.0335864905755,13.3239667836351) -> (1298226.2344595,2919045.4523473,0)
Metadata:
TIFFTAG_MAXSAMPLEVALUE=255
TIFFTAG_MINSAMPLEVALUE=0
TIFFTAG_RESOLUTIONUNIT=3 (pixels/cm)
TIFFTAG_XRESOLUTION=800.26886
TIFFTAG_YRESOLUTION=800.14081
Image Structure Metadata:
INTERLEAVE=BAND
Corner Coordinates:
Upper Left ( 0.0, 0.0)
Lower Left ( 0.0,18492.0)
Upper Right (18565.0, 0.0)
Lower Right (18565.0,18492.0)
Center ( 9282.5, 9246.0)
Band 1 Block=18565x1 Type=Byte, ColorInterp=Gray
Overviews: 4642x4623, 2321x2312, 1161x1156, 581x578, 291x289, 146x145, 73x73, 37x37
```
and the `IQALUIT_1948_A11535_043.tif.aux.xml` file:
```xml
<?xml version="1.0" encoding="utf-8" ?>
<GeodataXform xsi:type='typens:PolynomialXform' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'
xmlns:xs='http://www.w3.org/2001/XMLSchema' xmlns:typens='http://www.esri.com/schemas/ArcGIS/9.2'>
<PolynomialOrder>1</PolynomialOrder>
<SpatialReference xsi:type='typens:ProjectedCoordinateSystem'>
<WKT>PROJCS["Canada_Lambert_Conformal_Conic",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-96.0],PARAMETER["Standard_Parallel_1",50.0],PARAMETER["Standard_Parallel_2",70.0],PARAMETER["Latitude_Of_Origin",40.0],UNIT["Meter",1.0]]</WKT>
<XOrigin>-35105400</XOrigin>
<YOrigin>-29255500</YOrigin>
<XYScale>128287945.084531</XYScale>
<ZOrigin>-100000</ZOrigin>
<ZScale>10000</ZScale>
<MOrigin>-100000</MOrigin>
<MScale>10000</MScale>
<XYTolerance>1.55899293474704E-08</XYTolerance>
<ZTolerance>0.0002</ZTolerance>
<MTolerance>0.0002</MTolerance>
<HighPrecision>true</HighPrecision>
</SpatialReference>
<SourceGCPs xsi:type='typens:ArrayOfDouble'>
<Double>16.5886813769484</Double>
<Double>11.2421187314794</Double>
<Double>16.8939942179049</Double>
<Double>11.7402607351451</Double>
<Double>18.8921073940182</Double>
<Double>10.0052797183835</Double>
<Double>21.4572641379127</Double>
<Double>13.0572806764721</Double>
<Double>19.6528779424261</Double>
<Double>13.8720869249719</Double>
<Double>20.6880569996538</Double>
<Double>12.0845177405408</Double>
<Double>21.5855745124354</Double>
<Double>11.8220205578855</Double>
<Double>19.6699549399509</Double>
<Double>11.5899398962065</Double>
<Double>19.2596578670837</Double>
<Double>14.6946775183915</Double>
<Double>18.8790359460127</Double>
<Double>12.7118694177316</Double>
<Double>17.0335864905755</Double>
<Double>13.3239667836351</Double>
</SourceGCPs>
<TargetGCPs xsi:type='typens:ArrayOfDouble'>
<Double>1298609.77217853</Double>
<Double>2919147.39696529</Double>
<Double>1298500.0219128</Double>
<Double>2919153.17329506</Double>
<Double>1298631.40807544</Double>
<Double>2919617.77480046</Double>
<Double>1297892.90562009</Double>
<Double>2919783.3167529</Double>
<Double>1297910.23024105</Double>
<Double>2919417.7417536</Double>
<Double>1298127.44460173</Double>
<Double>2919739.01694754</Double>
<Double>1298091.07382506</Double>
<Double>2919911.77813673</Double>
<Double>1298297.65636365</Double>
<Double>2919614.6948765</Double>
<Double>1297815.43048519</Double>
<Double>2919292.29625073</Double>
<Double>1298182.37712172</Double>
<Double>2919377.79059004</Double>
<Double>1298226.2344595</Double>
<Double>2919045.4523473</Double>
</TargetGCPs>
</GeodataXform>
```
I don't understand the units of the ESRI sourceGCPs - why the values are so small. Is it an offset instead of a pixel position, or coordinate?
What is the correct `gdalwarp` command to use to get this to warp properly? (the same projected CRS as the source can be used for the target.)
(I've already looked at https://gis.stackexchange.com/questions/426418/create-rectified-geotiff-given-aux-xml-produced-from-arcgis)
thanks