Legacy ImageMagick Discussions Archive

Testing for an issue reported at viewtopic.php?f=27&t=32596

I get a different looking histogram when saving the red channel of a tif to JP2 than I do with PNG. I have tested with IM 7.0.6.10 and IM 6.9.9.10

input tiff:
http://www.fmwconcepts.com/misc_tests/h ... g/luna.tif

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magick luna.tif -channel r -separate -quality 0 luna_r.jp2

http://www.fmwconcepts.com/misc_tests/h ... luna_r.jp2

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magick luna_r.jp2 histogram:luna_r_hist.gif

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magick luna.tif -channel r -separate luna_r.png

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magick luna_r.png histogram:luna_r_png_hist.gif

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magick compare -metric rmse luna_r.jp2 luna_r.png null:

114.797 (0.0017517)

So there is a slight difference is the two images. Would this slight difference cause the spikes in the jp2 histogram that is seen above?

Thanks for the problem report. We can reproduce it and will have a patch to fix it in GIT master branch @ https://github.com/ImageMagick/ImageMagick later today. The patch will be available in the beta releases of ImageMagick @ https://www.imagemagick.org/download/beta/ by sometime tomorrow.

This commit fixed it: https://github.com/ImageMagick/ImageMag ... 446a59b6e0

Legacy ImageMagick Discussions Archive

possible bug histogram of JP2

possible bug histogram of JP2

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Re: possible bug histogram of JP2