2014.12.15 17:49 "[Tiff] Unnecessary bigger JPEG-compressed TIFF", by Even Rouault

2014.12.21 00:30 "Re: [Tiff] Unnecessary bigger JPEG-compressed TIFF", by Bob Friesenhahn

Have you compared JPEG-compressed TIFF output sizes with original JPEG files?

Perhaps GraphicsMagick (and ImageMagick) are doing something wrong, but TIFF with JPEG compression is looking a *lot* larger than original JPEG files:

Caused by my recent change?


Perhaps due to -quality 90? You should make sure to use the same quality settings, and for the comparison to be fair, you should use the same input file.

The original JPEG input used a quality factor of 90.

And from my testing with old imagemagick it seems that gm convert doesn't produce a YCbCr JPEG-compressed TIFF.


Does YCbCr make that big of a difference?

Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/