2024.02.08 02:44 "Re: [Tiff] error reading linearRaw subIFD from a TIFF file with libtiff built with libjpeg-turbo?", by Ellen Johnson

Hi Bob and Darrell,

Thank you both for your replies about GraphicsMagick and libjpeg-turbo (respectively).

Yes, per Darrell's reply: When I replaced our old libjpeg v6b with libjpeg-turbo – In our JPEG I/O codebase, I had to make the modifications for the new J12SAMPLE, J16SAMPLE, and related bit-specific functions (i.e., jpeg12_read_scanlines, jpeg16_read_scanlines, etc.).

Bob: For libtiff, I saw this in the config output when I built tiff with libjpeg-turbo, which appeared to indicate that the dual mode should be used with libjpeg-turbo >= 2.2:

Support for external codecs:
 ZLIB support: yes
 libdeflate support: no
 Pixar log-format algorithm: yes
 JPEG support: yes
 Old JPEG support: yes
 JPEG 8/12 bit dual mode: yes (libjpeg turbo >= 2.2 dual mode)

Am I misunderstanding the meaning of dual mode in libtiff?

Thanks!

ellen