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Old 18th September 2018, 23:33   #5  |  Link
blob2500
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Join Date: Sep 2007
Location: Italy
Posts: 24
Quote:
Originally Posted by martynuzza View Post

-vbvpeak is macroblocks?!
No, isn't macroblocks.

Macroblock is video resolution dependent:

Macroblock rate [Mbs/sec] = Resolution/(macroblock dimension)*frame rate.
For Xvid/Divx Home profile (up to) 40500 mbs/sec = (720*576)/(16*16)*25 for PAL videos; (720*480)/(16*16)*30 for NTSC videos.

vbvpeak is "Max bits over any one second interval" in Xvid interface (your posted image). For Home Profile, it's "8000000" (not 40500).

I'm not sure, but vbvpeak is not very important (is for codec internal check only) and in official MPEG-4 SP/ASP profiles is absent. VBVpeak is satisfied already with others vbv parameters: Max bitrate and Buffer size of Home profile.

In Divx Profiles table in your post, matrix for Home Teather is, theoretically, h.263 only, but you can to use MPEG matrix too, "standard" (not "custom"). MPEG standard and H.263 are fully Standalone player compatible.
Note: That table I think is not fully correct: example: VBV size of HD 720p profile is not 2048 kB (this is for 1080p only); actually it is 768 kB (9708 kbps double bitrate of HT profile... so must be double size of HT vbv size too ) In Xvid interface all these values are correct for 'equivalents' DivX profiles too.

Last edited by blob2500; 19th September 2018 at 01:28. Reason: ...about macroblock/sec and matrix
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