2020.03.16 20:32 "Re: [Tiff] Old-Style JPEG Support", by Levi Wilson

Does

   ./tools/tiffcp -c jpeg old-style-jpeg.tif modern-jpeg.tif

work for you?

If this does not work (due to the same issue), then you might be forced to use tiffcrop instead.

I forgot to mention I tried that, and this is what it gets:

./tools/tiffcp -c jpeg old-style-jpeg.tif modern-jpeg.tif
TIFFReadDirectory: Warning, Unknown field with tag 32931 (0x80a3) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 32934 (0x80a6) encountered.
OJPEGSetupDecode: Warning, Depreciated and troublesome old-style JPEG compression mode, please convert to new-style JPEG compression and notify vendor of writing software.
OJPEGReadHeaderInfoSecStreamSof: JPEG compressed data indicates unexpected subsampling values.
/sandbox/02f04c98-48c7-4720-bfe7-b7ca2073c052_files: Error, can't read scanline 0.

So it sounds like what you'd described below in that this really old JPEG format was just unavailable

This is likely extremely old software and possibly dating to before Joris tried to make the old JPEG reader work better. If you run it without arguments, what version is reported?

it was 3.8.2.1...perhaps I can try snagging that one to do it; good call

You should be focusing on converting files using old JPEG compression to a well-supported format. Old JPEG compression was replaced in 1995 by the current compression scheme.

Old versions of libtiff should still be available as source code so if an old version works better, then this could allow you "save" your files so they are likely to work reliably in the future.

That's a great suggestion. Unfortunately we don't control the files that we get...a lot of times they're REALLY old files that come from document management stores. All we're trying to do is get "workable" copies of the pages so we can do other post-processing with them. So if that's the case, then trying to use an older version of tiffsplit would work for us, thanks!