[Gdal-dev] Missing pixels after warp

[Frank Warmerdam]

Stephen Woodbridge wrote:
> Hi,
> 
> I used gdal warp to mosaic some images and I seem to have some bit-rot 
> along the seams.
> 
> http://imaptools.com/temp/missing-pixels.png
> 
> The upper image is a 2 meter/pixel image that was stretched into a 1 
> meter/pixel file. Then the lower image which is 1 meter/pixel was 
> mosaiced into the same file.
> 
> This problem is probably exaggerated but the stretching the image into 
> the 1 meter/pixel file.
> 
> I have not had a chance to recreate this and look at the original source 
> files to see what they look like, but I'm wondering is anyone has any 
> tricks or ideas on how to avoid this?

Steve,

This looks like quite a serious issue.  I'd guess there are pixels being
identified as nodata, though it is hard to be sure.

If you can boil this down to a simple process to reproduce I'd be interested
in digging into it.  There is at least one somewhat related sounding bug
report in trac I hope to dig into.

Best regards,

-- 
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