Author Topic: H264, B-frame dropped (the return)  (Read 2928 times)

twinsun

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H264, B-frame dropped (the return)
« on: November 26, 2013, 06:19:25 AM »
A small video record H264.mp4, where B-frames are dropped, when browsing or x264 reencoding, by Avidemux (r8494 and 8971).
0204_062005_DVB-T_ORG.mp4 (28MB) :
http://rapidshare.com/share/D29E689F72E2DB5D5D0A233322C7954E

I have another one, doing Avidemux to drop B-frame on the original.
But a video/audio COPY, done by Avidemux itself, solves the problem.
No B-frames dropped, browsing or reencoding the copy.
It's a kind of solution.
Not the case of above linked video.

mean

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Re: H264, B-frame dropped (the return)
« Reply #1 on: November 26, 2013, 06:34:07 AM »
The file has invalid timestamps
Vlc is complaining also

twinsun

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Re: H264, B-frame dropped (the return)
« Reply #2 on: November 26, 2013, 09:54:38 AM »
My VLC 2.0.5 two flowers plays it silently, with no drop, so does MPC-HC (1.6.6).

twinsun

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Re: H264, B-frame dropped (the return)
« Reply #3 on: November 28, 2013, 06:03:48 AM »
This video has timestamps issues, that the issue.

PowerDirector12, Handbrake, Hybrid, also drop the same b-frames, and preview, encode with same drops as Avidemux do.
Like that some of your “call next frame” says empty, so call the next one, … and so miss the frame.

But,
VLC, MPC-HC, play it with no complaint (don't know why yours do), with all frames, no drop.
VLC and MPC-HC have a way to easily reach these frames.

How do they get rid of this timestamp issue.
Not an issue for them.
Looks strange to me, isn't.

twinsun

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Re: H264, B-frame dropped (the return)
« Reply #4 on: November 29, 2013, 04:31:45 AM »
Interesting.
Looking at why my MPC-HC plays so well what is tricky for others players/encoders.
There are many H264 decoder filters, far to be equal.

I check what appends around the first frame skipped by most tools, frame n°10 of the video (link above).

1 - MPC-HC 1.6.6.6957, use it's own internal filters.

   Internal video decoder → PERFECT, No issue


2 – MPC-HC 1.7.1 use LAV filters 0.59.1.26, instead of it's internal filters

LAV filters splitter options :
   VC-1 timestamps : path through or correction → drop issue

LAV filters video decoder options :
   LAV video decoder → drop issue
   DXVA2 (hardware) → drop issue
   Intel QuickSync (hardware)→ PERFECT, No issue

LAV video decoder, and others not listed here, are unable to access all frames.
On the other hand, Intel QuickSync, and MPC-HC internal filters, as video decoder, show that this video is fully usable.