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"-s" subsampling option of opj_compress does not work properly #377

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago 
with r2875, "-s" option given at opj_compress like this : 
opj_compress -i bike.ppm -o bike.ppm_s21.j2k -s 2,1

... produce a J2K image with the same size as the original but with a SIZ 
marker multiplied by 2 in the x-direction. It does not actually subsample, it 
multiplies the size signaled in the SIZ marker.

Original issue reported on code.google.com by antonin on 17 Jul 2014 at 7:56

GoogleCodeExporter commented 9 years ago 
I've been playing with subsampling in openjpeg lately and have had trouble 
determining if the issue is with the encoder (openjpeg) or the decoder 
(Safari). Whenever I use the openjpeg -s option, all images become distorted in 
Safari (or any Apple viewer), the images' dimensions are doubled in one or both 
dimensions when using anything but "1,1". The images display at the correct 
dimensions on Ubuntu.

I also notice that the file sizes are identical.

This issue is important to me, if there's anything I can do to help, let me 
know.

Original comment by njdo...@gmail.com on 20 Aug 2014 at 3:44