Re: Gif resize working but with error (for some images), why?
Posted: 2008-02-20T22:30:30-07:00
-deconstuct was NEVER a good optimization method for GIF images.
The new method that does work is -layers Optimize
See IM Example pages for all the details.
BOTH however can produce that message, as it means one of the frame did not need to overlay anything onto the results of the previous frames disposed image to generate the new frame. That is the frame overlay is ZERO in size. In that case IM gives a warning, and uses a single transparent pixel frame as a place holder in the animation sequence, so that disposal and time delays remain correct.
The animation will still have the correct result (according to what you requested, which may not be what you wanted!!!) The warning was just that a warning, it is not fatal, and the result is right.
You can tell IM to shut-up about such warnings, by setting a -quiet operational setting before that operation.
See IM Examples,
http://imagemagick.org/Usage/anim_basics/#deconstruct
http://imagemagick.org/Usage/anim_opt/#opt_frame
for details.
The new method that does work is -layers Optimize
See IM Example pages for all the details.
BOTH however can produce that message, as it means one of the frame did not need to overlay anything onto the results of the previous frames disposed image to generate the new frame. That is the frame overlay is ZERO in size. In that case IM gives a warning, and uses a single transparent pixel frame as a place holder in the animation sequence, so that disposal and time delays remain correct.
The animation will still have the correct result (according to what you requested, which may not be what you wanted!!!) The warning was just that a warning, it is not fatal, and the result is right.
You can tell IM to shut-up about such warnings, by setting a -quiet operational setting before that operation.
See IM Examples,
http://imagemagick.org/Usage/anim_basics/#deconstruct
http://imagemagick.org/Usage/anim_opt/#opt_frame
for details.