So you have a full video already and need it in .ANI form?
1) Download
RAD Video Tools if you haven't already. It's invaluable for working with almost any media - .bik, .smk, and standard extensions alike.
*A few things of note: Be sure your video is in a folder all its own, as the following output PCXs will all pile into the same directory.
Depending on the number of frames in your animation, you may want to add a "0" to the end of the output filename (say, "anim0.pcx") - RAD will automatically number them starting with frame 1 and adding zeros as needed (a 100-frame anim will run from 001 to 100). Since ANIBUILDER (recommended) needs a four-digit frame-number, adding the 0 will save you from having to renumber them all.
2) Open RAD and browse till you find your video - I recommend .AVI format, since that's what I tested with. Select it, then hit "Convert a file"
3) The Conversion menu will have a button up at the top labeled "Output Type" - choose PCX. There's also a checkbox for "Output as 256 colors," which you'lll want to check. Use palatte from the input file.
4) Look over the other options if you like;when you're ready, hit "Convert" over on the left - it'll take a while to run through all the frames.
5) Since ANIBUILDER requires [anim]0000.pcx as the first filename/frame it runs, I suggest just copying the first frame exported and renaming its frame number to 0000. If it's a looping anim, renaming the last frame to 0000 will also work (probably- that's up to you). Both of these options are simpler than renaming 0001 to 0000, 0002 to 0001, and so on... X.x;
6) You've got your .PCX's ready- just use ANIBUILDER to convert (you can try ACANI too if you want, but I couldn't get it to work :-p).
