Make interlaced JPEG as default normal and thumb format? Make interlaced JPEG as default normal and thumb format?
 

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Make interlaced JPEG as default normal and thumb format?

Started by cvictor, March 28, 2004, 06:58:34 PM

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cvictor

I'm using coppermine version 1.2.1 and find that the generated normal and thumb pictures are not interlaced (progressive) jpeg.
Interlaced jpeg pics are usually smaller in size while remaining the same quality. And users will see the pictures roughly under narrow bandwidth environment.
Please consider this suggestion in the next version, since 1.3 didn't include this feature.

Add one line in picmgmt.inc.php line around 185 will solve this in GD2.

// progressive jpeg output
imageinterlace($dst_img, 1);

I have never used IM before, but there must be some command line parameter doing the same thing.

Notice that when opened in IE, progressive JPEG pictures will not displayed progressively. On the contrary, it will be displayed as a whole after downloading completes. Even worse than the ordinary line-by-line fashion. :(