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Old 29th July 2014, 19:12   #2  |  Link
TheSkiller
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Join Date: Dec 2007
Location: Germany
Posts: 632
Quote:
Originally Posted by Deftoner View Post
and each should have a bitrate of about 0.04kbps. Is that correct?
No, subtitle streams do not have a fixed/constant bitrate; for sections where there's no subtitle in any of the streams the bitrate of all subtitle streams together is 0, and whenever a new subtitle appears in any of the streams, the size of it's RLE compressed bitmap adds to the total bitrate of video + audio (+ overall mux overhead). If the total bitrate (inculding subtitles and mux overhead) exceeds 10.08 MBit/s even once, the authoring fails.
With as much as 24 subtitle streams (and probably all sharing very similar subtitle timing) there might be quite some sharp bitrate spikes in some places... However, I think the problem lies in the video stream's maximum bitrate, see below.

Quote:
Originally Posted by Deftoner View Post
The problem is when i add the subtitle streams to my audio/video streams with an overall bitrate of about 7mbps
Overall (average) bitrate does not count; it's the maximum bitrate that counts here.

Try the following: use Muxman and add your video and all audio streams (no subtitles), and let it mux a dvd. Then post Muxman's log here. It will tell us the maximum bitrate of video + audio + mux overhead so we can see how much spare bitrate there is left for the subtitles.

Last edited by TheSkiller; 29th July 2014 at 20:18.
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