[gdal-dev] Create COG jpeg tiles with JFIF APPn markers

[Even Rouault]

Jose,
> Those tiles contain normal JPEG markers (SOI, SOF0, DQT) but no JFIF 
> marker (APP/n/) is added. How can I ensure adding this JFIF marker?

you can't, unless you're ready to patch the JPEG codec in libtiff to do that

I should point to 
https://www.awaresystems.be/imaging/tiff/specification/TIFFTechNote2.txt 
which mentions:

"Writers should avoid including "noise" JPEG markers (COM and APPn markers).
Standard TIFF fields provide a better way to transport any non-image data.
Some JPEG codecs may change behavior if they see an APPn marker they
think they understand; since the TIFF spec requires these markers to be
ignored, this behavior is undesirable."

Even

-- 
http://www.spatialys.com
My software is free, but my time generally not.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20220405/14c72b64/attachment.html>