Resizing Animated Gifs - How To?

Hi all.
I am not too sure that this is the correct forum for this question, so mods please move if required. I am trying to resize a couple of animated gifs - and have had success with a few, but others end up showing black frames etc., when they near the end of the cycle for one loop. Not being too knowledgeable about this process, and after trying different software, I went to this site:
http://www.gifworks.com and used their free online program. The resized gifs seem to work on their site, but when saved to my computer and displayed they have a black frame - either full or partial, or a negative frame - near the end of the loop. This does not happen with all the ones I have resized. Possible suggestions on how to remove the oddball frames would be appreciated. These do not show up if I separate the gif into its individual frames, only when played as animation. Could there be such a thing that the resizing should be done in steps, instead of just one larger resize?
Any information / help would be gratefully appreciated.

frums

I've resized animated gif fine with "Jasc Animation Shop" www.jasc.com or "Adobe Imageready" www.adobe.com to do a larger resize without needing to do several steps.Its possible the .gifs are being saved with a higher than necessary compression.

Hello Wonderingguy34, and thanks for your reply. I apologize for not replying sooner, but work called me away for a couple of days. I will check out the software you mentioned and see how it works. These are fairly large programs, was looking for something a little smaller just to resize a couple of animated gifs to make a couple of avatars. Will post back with results.

thanks again

frums

I tried the Jasc Animation Shop3 trial download and it worked perfectly. Used the same procedure - one step reduction - no blank/black frames etc., and even optimized the output making it much sharper and clearer. Don't know much about the compression settings stuff, just know it worked well.

Thanks for the info - it was / is greatly appreciated.

Problem solved.

frums