JPEG compression settings
PostPosted: Fri Aug 23, 2002 5:14 am
by Gregory C
Can anyone explain why Photoshop has compression rates from 1 to 12 while SilverFast only has rates from 1 to 10?
Does anyone know the differences other than in size of the resultant file?
regards
Gregory
PostPosted: Tue Aug 27, 2002 4:58 pm
by LSI_Belli
Dear Gregory,
the JPEG-librairies used in Photoshop and SilverFast are different.
There is a different scaling and "offset" of the compression rate, although both algorithms surely follow the JPEG-standards.
If you compress an image with a quality rate of 0 in both programs, you'll notice that the image obtained with SF is smaller in size and rougher than the one obtained in PS. In the same way, the compression with the best quality rate (12 for PS and 9 for SF) yields to a larger and finer image in PS than in SF.
Regards.
Thomas