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NOTE: Sometimes Powerpoint requires extra settings for continuous looping of GIFs. Go to the "video tools" menu, which contains "format" and "playback". Under the playback menu, there is a button "Loop until stopped". Click on it, to allow continuous loops! (Thanks to Jean-Noël for this)
Tip: Transparent background
You can also use convert to replace any white in the image with a transparent background:
convert input.gif -fuzz 10% -transparent white output.gif
Example Metview Macro
The following macro retrieves data from MARS, plots it to a PostScript file and uses the convert command to generate an animated gif.
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