https://bugs.documentfoundation.org/show_bug.cgi?id=56178
--- Comment #17 from Julien Nabet <[email protected]> --- Giving a new try here, I saw that LO enters CCIDecompressor::Read2DScanlineData. It's expected since Group 4 uses 2D. But on several lines (which corresponds about the number of garbage lines), it failed to read "n2DMode" value. See https://opengrok.libreoffice.org/xref/core/vcl/source/filter/itiff/ccidecom.cxx?r=946b17b4#1014 Taking a look at CCIDecompressor::ReadCodeAndDecode, the only case where m_bStatus is false is when nCodeBits = 0 and it happens when the nCode isn't in an initialized area of "pLookUp" (in our case m_p2DModeLookUp). Now the main pb is to find doc about CCITT group 4 for tiff. TIFF specs can be found here: https://www.itu.int/itudoc/itu-t/com16/tiff-fx/docs/tiff6.pdf, the 2 related sections are: - Section 10: Modified Huffman Compression - Section 11: CCITT Bilevel Encodings Also found https://www.itu.int/rec/dologin_pub.asp?lang=f&id=T-REC-T.6-198811-I!!PDF-E&type=items which at least explains the table CCI2DModeTable (see https://opengrok.libreoffice.org/xref/core/vcl/source/filter/itiff/ccidecom.cxx?r=946b17b4#266). Now is LO decode process is ok but the tiff is not standard (however no pb to open it on Gimp), is the process ok with just something lacking or is completely ko (but in this case the whole image would be garbage)? -- You are receiving this mail because: You are the assignee for the bug.
