2020.08.03 21:27 "[Tiff] Unable to read a large TIFF File (single image, one IFD, Strip image of size 2.6 GB) on Unix using TIFFClientOpen API", by Upanita Goswami

2020.08.16 12:32 "Re: [Tiff] Unable to read a large TIFF File (single image, one IFD, Strip image of size 2.6 GB) on Unix using TIFFClientOpen API", by Adam Richter

Hi, Upanita and TIFF developers.

I am trying to make a test for the patch I included in this thread for _TIFFPartialReadStripArray in libtiff/tif_dirread.c. So far, I have not been able to cause the function to be called at all by using the utility programs included in the libtiff build. I believe that in order for the function to be called at all, it is currently necessary either to build libtiff with "./configure --enable-defer-strile-load", or pass the "O" mode string character argument for functions like TIFFOpen and possibly "D", too.

The test that I was hoping would reproduce this problem is this, after I rebuild with "--enable-defer-strile-load" and modify tools/tiffcp.c to include "DO" in the mode string it passed to TIFFOpen when opening the source tiff file:

gm convert -size 32768x16384 -depth 32 xc:white tiff:3gb.tiff
LD_LIBRARY_PATH=./libtiff/.libs ./tools/.libs/tiffcp 3gb.tiff  3gb-copy.tiff

Anyhow, if anyone would like to suggest a command line that should cause _TIFFPartialReadStripArray to be called, that would be most welcome.

Adam