How to extract frames from a GIF file preserving frame dimensions

Question

I have the following GIF image file:

I want to extract its frames (using PGM output format) using this imagemagick command:

convert brocoli.gif out%05d.pgm 

But each frame has a different size.

How can I extract its frames while preserving the original gif file size?

Answer 1

Use the -coalesce option:

convert -coalesce brocoli.gif out%05d.pgm