Animated signature GIFS from AVI files Tutorial. (Linux)

[Xerxes]

Note: This is reasonably advanced and hinges on you having Linux or Cygwin installed to carry this off. This tutorial uses only free software.

NOTE: you will need these installed: Imagemagick, Mplayer, Mencoder (which may be part of Mplayer) and any dependancies for them. Use "sudo apt-get install" to get them.

1. If you are converting only an AVI, skip to step 10. If you wish to convert Youtube videos, continue.
2. Navigate to your home directory (any will do, but for simplicity everything will be done here).
3. Create a document called "youtube.sh", omitting the quotation marks.
4. Open the file using whichever editor you want and add this code:
   

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   wget -q -O - http://www.youtube.com/watch?v=$1|grep "/watch_fullscreen?.*video_id=.*\&t="|sed "s/^.*\&t=//"|sed "s/\&.*//"|xargs -i wget -O $2 http://youtube.com/get_video?video_id=$1\&t={}\&fmt=22

   Note that this will download the HD version of the youtube video in question, which might not exist. Try removing the &fmt=22 from the end to download the low quality version. HD versions are preferable, however as they don't have the artifacts and distortion of the normal youtube clips.
5. Open a terminal.
6. Run "chmod +x youtube.sh" to allow you to run the file as a script (again, omit the quotation marks).
7. Find the video ID that you want to download by taking the unique identifier from the end of the youtube URL.
8. Call the script:
   

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   ./youtube.sh ID OutputFLV.flv

   . Obviously you can call the output file whatever you like. You will now have an FLV sitting in your home directory.
9. Convert the FLV into an AVI (it is possible to convert from FLV->GIF, but the quality is horrible):
   

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   mencoder -oac pcm -ovc lavc -o OutputAVI.avi OutputFLV.flv

   You will now have the FLV converted to an AVI file.
10. You may now select the parts that you want to include by running avidemux, if you wish. Use the A/B buttons on the bottom right to select the parts and save the file.
11. Now make a temporary file to save the individual frames from your AVI:
    

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    mkdir ~/gif && cd ~/gif

    This will make a folder called "gif" in your home directory and change directory to it.
12. Now, use Mplayer to convert EVERY frame into a jpeg:
    

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    mplayer ~/OutputAVI.avi -vo jpeg

    Note, this will take up a LOT of space.
13. You can now edit out the frames you do and don't want.
14. Now, all that is left to do is convert the frames to a GIF!
    

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    convert -enhance -resize 150x150 -delay 4 -loop 0 *.jpg ~/Desktop/FinalOutput.gif

    
    Your computer will probably freeze for a while at this point. Don't panic, just leave it to do its thing.
    The options are: resize (set to 150px*150px here), delay (4ms before starting), loop (0=infinite) and *.jpg which looks for every sequential JPG. Note that the file will be on your Desktop now.

Voila! You have a high quality GIF!

Example:

I created this tutorial whilst learning how to convert avis for Saggy's requested avatar/sig. Note, the file is 6.3Mb as I haven't optimised it yet. . Link.


Youtube grabbing script adapted from: http://www.chuckcaplan.com/blog/archives/2007/07/how_to_convert_1.html

[bullet_sponge]

nice!

Thanks for that.

Now... If only I wasn't lazy!

[Xerxes]

Well, I'll make a bash script for it at some point...

[Podge]

Good job man.

[Xerxes]

Thanks to both of you...at a later point I'll see if there are windows ports of the necessary programs...

[bullet_sponge]

following this on 9.04, sees as though I need to download avidemux separately.