[Gdal-dev] Problems with warping

[Frank Warmerdam]

Hugo Martins wrote:
> Hi gdal folks,
> 
> Well i have been experiencing some problems with gdalwarp. I downloaded 
> some imagery in jpg format. After i converted it to tif and no problem 
> happened. These images are in Lisboa Hayford Gauss IgeoE projection and 
> i need to reproject them to WGS84. Here are the gdalinfo from both files:
...
> As you see, there is some shift with the WGS84 projection.
> Could somebody help me on this?

Hugo,

I'm not clear on what exact problem you are seeing.  The lat/long bounds
of the original file and the gdalwarp file will be somewhat different since
the output file has been reprojected.  Generally speaking I would expect the
output file to represent a slightly larger area and if you look at the image
that there would be black triangles at the corners as a result of the
rotational effect of reprojection.

Best regards,
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