Created attachment 114917 [details] Garbled image When saving a TIFF image 'CCITT Modified Huffman RLE' causes the image to become garbled. I've attached a pure white image saved in this method.
This looks like a regression: it works with krita 3.3.3.
According to the TIFF standard, this compression mode is defined for 1 bit-per-pixel images only. So I think we should just remove this option (alongside other two "fax" options). === Snip from the standard === 2 = CCITT Group 3 1-Dimensional Modified Huffman run length encoding. See Appendix B: "Data Compression -- Scheme 2." BitsPerSample must be 1, since this type of compression is defined only for bilevel images. When you decompress data that has been compressed by Compression=2, you must translate white runs into 0's and black runs into 1's. Therefore, the normal PhotometricInterpretation for those compression types is 0 (WhiteIsZero). If a reader encounters a PhotometricInterpretation of 1 (BlackIsZero) for such an image, the image should be displayed and printed with black and white reversed.
Git commit 5db89dc523fb35e17fd00a2ec204a28405c7ce06 by Dmitry Kazakov. Committed on 13/09/2018 at 15:20. Pushed by dkazakov into branch 'master'. Remove fax-related tiff options In fax mode tiff can store only 1 bit per channel images, which Krita doesn't support. So just remove these options from the GUI M +1 -6 plugins/impex/tiff/kis_dlg_options_tiff.cpp M +4 -10 plugins/impex/tiff/kis_tiff_converter.cc M +0 -1 plugins/impex/tiff/kis_tiff_converter.h M +0 -1 plugins/impex/tiff/kis_tiff_writer_visitor.cpp M +51 -78 plugins/impex/tiff/kis_wdg_options_tiff.ui https://commits.kde.org/krita/5db89dc523fb35e17fd00a2ec204a28405c7ce06
Git commit ebc0b62c3cb0531094a022fa637753ad29315eff by Boudewijn Rempt, on behalf of Dmitry Kazakov. Committed on 15/09/2018 at 09:08. Pushed by rempt into branch 'krita/4.1'. Remove fax-related tiff options In fax mode tiff can store only 1 bit per channel images, which Krita doesn't support. So just remove these options from the GUI M +1 -6 plugins/impex/tiff/kis_dlg_options_tiff.cpp M +4 -10 plugins/impex/tiff/kis_tiff_converter.cc M +0 -1 plugins/impex/tiff/kis_tiff_converter.h M +0 -1 plugins/impex/tiff/kis_tiff_writer_visitor.cpp M +51 -78 plugins/impex/tiff/kis_wdg_options_tiff.ui https://commits.kde.org/krita/ebc0b62c3cb0531094a022fa637753ad29315eff
Git commit 49788da184fe01c571780e792498f032700bd629 by Dmitry Kazakov, on behalf of L. E. Segovia. Committed on 19/07/2021 at 05:44. Pushed by dkazakov into branch 'master'. TIFF: fix display of options for Pixar log compression The index for the codecsOptionsStack wasn't updated to account for the removal of the fax options in 5db89dc523fb35e17fd00a2ec204a28405c7ce06. M +1 -1 plugins/impex/tiff/kis_dlg_options_tiff.cpp https://invent.kde.org/graphics/krita/commit/49788da184fe01c571780e792498f032700bd629