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2021.06.17 16:34 "[Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Even Rouault
2021.06.18 15:00 "Re: [Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Guido Vollbeding
2021.06.18 15:11 "Re: [Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Even Rouault
2021.06.18 16:10 "Re: [Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Guido Vollbeding
2021.06.18 16:13 "Re: [Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Even Rouault
2021.06.18 16:59 "Re: [Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Kemp Watson
2021.06.18 17:25 "Re: [Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Even Rouault

2021.06.17 16:34 "[Tiff] IJG libjpeg-9d breaks libtiff JPEG-in-TIFF compression", by Even Rouault

Hi,

I've identified that a change in IJG libjpeg-9d (9c works fine) causes default Huffman tables to no longer been created in jpeg_set_defaults(), but deferred to a later point. That changes breaks libjpeg usage by libtiff when generating JPEG-compressed TIFF images, where the JpegTables tag (https://www.awaresystems.be/imaging/tiff/tifftags/jpegtables.html) can contain Huffman and/or quantization tables (more details about that tag can be found in the "JPEGTables field" paragraph of https://www.awaresystems.be/imaging/tiff/specification/TIFFTechNote2.txt). We have found a workaround in the meantime with https://gitlab.com/libtiff/libtiff/-/merge_requests/255, by manually creating the default Huffman tables, but it is a bit unfortunate that we have to do that.

Best regards,

Even

http://www.spatialys.com
My software is free, but my time generally not.