Re: Resultant image size over expected
Posted: 2009-02-17T12:41:23-07:00
IM does not know or use the jpg compression quality of the input images and defaults to its own compression quality of 85. You will need to add -quality XX to your command at the end to force a quality that gives you acceptable image size.epoussif wrote:I use convert -append to build a big image based on a group of tiles. They are .jpg. As far as I understood, convert generates an uncompressed version of each tile, make the appending into an uncompressed resultant file and then it's compressed again. But my result is about 40% bigger than the sume of the sizes of the original pictures.
Am I doing something wrong? I don't want to loose quality, but I don't need less compression than in the input files (I don't know their compression values).
Thanks in advance,
Ernesto
Also if you are on a 16-bit IM and had 8-bit images, IM will produce a 16-bit result. So you may want to add -depth 8 to your command line.
See
http://www.imagemagick.org/script/comma ... .php#depth
http://www.imagemagick.org/script/comma ... hp#quality
http://www.imagemagick.org/Usage/formats/#jpg