Autodesk Animator Codec

• FourCCs: AASC
• Company: Autodesk
• Samples: http://www.mplayerhq.hu/MPlayer/samples/V-codecs/AASC/

Autodesk Animator Codec (AASC) is a 24-bit Run Length Encoding algorithm similar to Microsoft RLE.

Decoding Algorithm

A frame of AASC data is decoded bottom row first and the decode operation iterates to the top row.

• foreach row from bottom to top
  • read the next byte from the encoded stream as the RLE code
  • if RLE code is 0
    • read the next byte from the encoded stream as the command code
    • else if the command code is 0
      • row decode finished; move to the next row
    • else if the command code is 1
      • frame decode is finished
    • else if the command code is 2
      • reposition the frame decode coordinates:
      • read the next byte as the number of pixels to move to the right
      • read the next byte as the number of rows to move up
    • else
      • copy the next (command code) pixesl from the encoded byte to the output image
      • if the command code is odd
        • skip the next byte in the encoded bytestream
• else
  • read the next byte as the pixel
  • write the pixel into the output image (command code) times