How do you reduce the file size (not dimensions) of an animated .gif?

[gifted_reality16B6]

What is the best way to reduce the file size of an animated .gif? I have created a 72 frame animation. Although my .gif document is only 72 dpi and 600 x 451 pixels, when I File > Export > Save for web (as a .gif) the file is 20 MB. Too large to email or post to my blog. Do you have a solution that you would like to share?

[Derek Cross]

Experiment with reducing the number of colours from 256 to fewer.

[davescm]

Try :

1. Reducing the frame rate which in turn will reduce the frames required.

2. Reducing the colours or changing from perceptual

3. Try a 3rd party optimisation tool.

Dave

[gifted_reality16B6]

Dave,

Thank you for taking time out to aswer my query. Although I did try all of these options, I was only able to cut the file size from 20 MB to 9 MB. I really appreciate the response. The strange thing is that an MP4 export is only 4MB.

[rayek.elfin]

Nothing strange about that: GIF is an old-fashioned and rather unoptimized non-lossy compression algorithm not meant for optimized video/animation compression.

(not my text:):

An animated GIF is a very bad compression format for a few reasons. First of all GIF uses LZW (which was defined in 1984), which is not a good compression format for lossless compression (deflate used by Zip is better and newer formats are even better than that), second GIF only uses 8 bit paletted images (up to 256 indexed colours), so the necessary quantisation usually introduces noise that makes compress worse. Third and that is the main reason, GIF is not a movie compression format at all, it stores the differences between consecutive image but does that in a lossless manner, which is not useful for movies.

GIF inherently compresses less than “lossy” DCT compression as in MPEG. Furthermore, each frame in a GIF animation is independent of all the other frames. In MPEG. Generally and MPEG stream has I-Frames that encodes the entire frame and P-Frames that are encodes from the previous frame.

MP4 or other video formats give a much smaller file while the image quality is better than animated GIF.

(my text:)

Also, all browsers now support Animate PNG files. If transparency is required, APNG is much preferred now: 1) better non-lossy compression compared to GIF, 2) full alpha transparency of 256 values (GIF only supports 1bit transparency - either on or of), 3) support for more than 256 colours.

[gifted_reality16B6]

You have given me a lot to think about here. Thanks for taking the time to explain that in such depth.

[Shortline25307483ijmg]

My solution was to change the size after I hit export..toward the botton of the screen that comes up I changed to 600x400 and when it exported I got 562kb which was small enough to upload onto a website a display. Not sure why the size of the gif when I hit export defaulted back to the original photo size, but adjusting back to the 600x400 size did the trick.