How can I reduce the dimensions of gif images with ImageMagick?

Question

What flag in magick.exe convert <flags> will reduce the dimensions of my image?

This is the command I'm using: magick.exe input.png[0] -depth 8 -type Grayscale -dresize 400x300.

The [0] after the source-image filename is meant to strip the first frame of any animated gifs.

How can I do reduce my output gif sizes? My file sizes are too large: my outputs need to be less than 100k. Any methods other than reducing the dimensions are also welcome.

Answer 1

convert test.gif -fuzz 10% -layers Optimize result.gif 

Adding a -fuzz 2% produced a better optimization, but still not very good. At -fuzz 15% It isolated the differences for frame optimization to just the visible color band changes I noted before. At 25% the differences were almost to just the text changes.

Finally at a massive 30% fuzz factor (ignore color changes below that figure, did it optimize to just the text changes.

Answer 2

You can try gifsicle:

gifsicle -O3 old.gif -o new.gif 

If it's an animation, you could try skipping frames (see how it works).