[gdal-dev] Re: georeference and project a jpeg

[Jukka Rahkonen]

jdmorgan <jdmorgan <at> unca.edu> writes:

> Hello, 
     I am attempting to georeference and project a
       jpeg image
       using only gdal tool.  I
       have georeferenced
       the jpeg using the following command:  
     gdal_translate
       -a_srs EPSG:102719 -of HFA -gcp 0.0 0.0
       -82.5586187839508 35.59414007259327 -gcp 0.0 410.0
       -82.55858659744263
       35.5937998255945 -gcp 520.0 0.0 -82.55741715431213
       35.594340730401775 -gcp
       520.0 410.0 -82.55728840827942 35.5940266570877 
NCDCLogo.jpg NCDCLogo.img 
.....
     Derek



I made a test with some holiday picture jpeg and this way it works for me.

Step one
========
gdal_translate -of GTiff -gcp 0 0 -82.5586187839508 35.59414007259327 
-gcp 0 410
-82.55858659744263 35.5937998255945 -gcp 520 0 -82.55741715431213
35.594340730401775 -gcp 520 410 -82.55728840827942 35.5940266570877
 test.jpg
test_temp.tif

Step two
========
gdalwarp -s_srs epsg:102719 -t_srs epsg:102719 test_temp.tif test_final.tif

It seems that
1. Imagine format is not right for holding ground control points.
Use GeoTIFF instead.
2. It may be not good to give -a_srs together with -gcp for gdal_translate.
At least it is not necessary. Just add gcp's first.


-Jukka Rahkonen-