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Old 26th May 2004, 15:50   #19  |  Link
Boulder
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Join Date: Mar 2002
Location: Finland
Posts: 5,718
Here's a little spreadsheet that I created, heavily inspired by good ol' DDogg:

http://www.saunalahti.fi/sam08/kbps_calc.rar

It simply calculates the average bitrate for each movie (I assume you put 2-3 video streams per disc) based on compressibility, using CCE's OPV. Here's how it goes:

1) The number of frames per movie is known
2) The framerate is known
3) A 1-3% sample is encoded as DDogg has explained in this thread
4) The avg bitrate for the sample is known (use DDogg's spreadsheet for that or Bitrate Viewer)
5) The avg bitrate is used to calculate how big the file would be with a full encode
6) Total filesize = movie1 + movie2 + movie3
7) The sheet calculates how many percent each movie would be of the total filesize
8) The percentage is used to calculate the amount of megabytes each movie will get
9) The video bitrate is calculated from the amount; audio bitrate is deducted
10) For QCCE users (like me ) the sheet also calculates the 'target size', that is, the amount of megabytes the video should take

I used 4350 MB as the free space on DVD for video, audio and subs, no need to calculate any muxing overhead etc. I've noticed that this leaves only a little bit space unused.

I'm not 100% sure if this works as it should so feel free to let me know of any problems/errors. I'm only a Pig on the wing you see
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