Samuel,
This is what I did to georeference the image (probably quicker for you
to do this than download it from my computer) :
1. Download from http://imagens.dgi.inpe.br/cdsr/vgeorge472433/ an unzip
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.tif
<http://imagens.dgi.inpe.br/cdsr/vgeorge472433/CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.tif.zip>,
2. Reproject it to epsg:4326 :
gdalwarp -t_srs epsg:4326 CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.tif
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.tif
3. Remove the localisation info (useful for me to get the control points
in image pixel coordinates, might not be necessary for you now):
tiffcp CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.tif
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.raw.tif
4. Associate control points (file gcp1.opts is attached, see below how I
made it) with the image :
gdal_translate --optfile gcp1.opts -a_srs epsg:4326
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.raw.tif
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.raw.gcp1.tif
5. Warp the image based on the control points (-r lanczos option is
optional) :
gdalwarp -r lanczos
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.raw.gcp1.tif
CBERS_2B_HRC_20091009_146_C_111_2_L2_BAND1.epsg4326.raw.gcp1.lanczos.tif
That's it.
The longest part is to define the control points.
QGis has a georeferencing plugin (and an OSM plugin), but I couldn't get
it to work to the end for me, so I only used it to match image pixel
coordinates with long/lat coordinates, using characteristic features
from the image also present in OSM, while at the same time using JOSM to
spot the features that looked most accurate from gps tracks. Then I
edited the file saved from QGis, to put it in the format usable by
gdal_translate.
If people would like to help in georeferencing, producing this GCP file
for a given image would be most helpful, since it is otherwise a
mechanical process to apply it to the image. If needed, I could try to
give more explanations on this.
Best wishes,
Jean-Guilhem
-gcp 6753.455483744225603 6603.512845967367866 -35.728441400000001
-9.681761000000000
-gcp 8082.076769333650191 5560.697172273251454 -35.698329800000003
-9.658776899999999
-gcp 8182.589123424650097 4324.001050859477800 -35.695995500000002
-9.630646000000000
-gcp 4586.245832160229838 1590.248025270976996 -35.777304500000000
-9.566079800000001
-gcp 1341.132685793631936 10502.343421339712222 -35.851000100000000
-9.766892900000000
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