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[Ostsol]

I started looking at the CMV file format and have noted a few things:

• Each frame of animation is stored in 4000 byte blocks
  
• Frames are stored in ZLIB compressed blocks of up to 200 frames
  
• The first compressed block starts at 12824 in the file, unless there is sound
  
• If there is sound, the block starts 200 bytes later
  
• That 200 byte block seems to store sound filenames padded by bytes of ASCII code 0xCC.
  
• The rest up until the four bytes before the first block is exactly 12.5 KB of ASCII code 0xFF
  

My questions:

• Other than the file header, is there anything important in the first 20 bytes of the file?  I've noticed that it changes only when there's sound in the movie.
  
• Is the padding between each sound filename just junk?  Are the filenames simply evenly spaced within that 200 byte block?
  
• What is the purpose of that 12.5 KB block of 0xFFs?

[Jifodus]

Here's what I decoded awhile back in April.
http://www.dwarffortresswiki.net/index.php/User:Jifodus/CMV_file_format

Edit: I'll clarify the 0xCC here since it isn't on that page, that's the "unused memory" marker byte that MSVC uses.

[ November 26, 2007: Message edited by: Jifodus ]

[Ostsol]

Thanks!  That helps alot.  

[Rick]

quote:Originally posted by Jifodus:
<STRONG>I'll clarify the 0xCC here since it isn't on that page, that's the "unused memo</STRONG>

int 3