this requires photoshop and quicktime pro:
1. Start by opening up the movie file that you'd like to make a GIF from in Quicktime Pro.
2. Once the file is open drag the selection cursors across the exact clip you'd like to animate from the beginning of the scene to the end, like this:
4. Now go to File --> New.
This leaves you with only the scene you want to animate in the Quicktime window:
6. Go to file ---> Save As:
When the Save As dialogue box pops up, name the file whatever you'd like, and make sure "Save as a self-contained movie" is checked off, and then click Save:
7. The next step is to open up Photoshop, once you've done this go to File --> Import --> Video Frames To Layers:
8. Find your video and click "load":
9. When the next dialogue box appears, leave the settings as they are and click "OK":
10. Your video is now opened up in Photoshop, with each frame making up a separate layer in your document. All you have to do now is go to Window --> Animation, and simply prompt the animation toolbar to come up:
11. After the animation toolbar appears at the bottom of the screen, go to File --> Save For Web & Devices:
12. Once the Save For Web & Devices dialogue box pops up, choose "gif" (beneath the preset menu) from the drop down menu on the top right (it may appear as jpeg, or png when first opened). Sticking with these settings usually works out:
Voila, you now have a gif: