Re: Making Thumbs
Posted: 2007-11-19T17:59:56-07:00
It is strange that the smaller (near same size) resizes is slower. That does not make sense, knowning the resize algrothim that is being used. It should be the oppiste. the larger the image the more pixels that need processing, and the larger the resize convolution filter used, and slower it becomes.
This is why -thumbnail will do a -scale of image that are more than 5 times larger first before applything the final resize.
Basically you results does not may sense.
PS: you can do BOTH commands on the one command line
and use a -layers optimize to at least attempt to re-optimize the animation after resizing. Please note however that GIF does not handle semi-transparent pixels, so resized GIFs are usally better performed after 'flattening' the animation onto a opaque background.
See IM examples... Animation: Basics, Optimization, Modifications
This is why -thumbnail will do a -scale of image that are more than 5 times larger first before applything the final resize.
Basically you results does not may sense.
PS: you can do BOTH commands on the one command line
and use a -layers optimize to at least attempt to re-optimize the animation after resizing. Please note however that GIF does not handle semi-transparent pixels, so resized GIFs are usally better performed after 'flattening' the animation onto a opaque background.
See IM examples... Animation: Basics, Optimization, Modifications