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Old 10th April 2016, 10:53   #947  |  Link
r0lZ
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I'm working on the processing of the audio by BD3D2MK3D (to allow the user to convert the AC3, THD and EAC3 streams to AAC too), and I verify if it works correctly in MKV-3D input mode too. And I have a problem !

I use a short movie with an E-AC3 (DD+) track to do my tests. When I demux the E-AC3 track from the BD with tsMuxeR or eac3to (without the option to keep only the core), I get a file of 19,961 KB. When I retrieve only the core, the file size is 11,406 KB. MediaInfo recognises the files correctly as AC3+ or AC3. So far so good.

But when I convert the movie to 3D-MKV with MakeMKV and I ask to keep the whole AC3+ file and the AC3 core, it creates two streams in the MKV container: the AC3+ and the AC3. That seems correct. But when the AC3+ stream is extracted with tsMuxeR (without the core option), its size is only 8,555 KB. (The size of the AC3 stream is correctly 11,406 KB.) And MediaInfo doesn't recognise the AC3+ stream it at all. It prints only its file size.

Demuxing the same stream from the 3D-MKV with eac3to gives the same result, but it prints an error message:
Code:
MKV, 1 video track, 5 audio tracks, 0:03:02, 24p /1.001
1: h264/MVC (right eye), English, 1080p24 /1.001 (16:9)
2: TrueHD, English, 7.1 channels, 48kHz
   "Surround 7.1"
3: AC3, English, 5.1 channels, 640kbps, 48kHz
   "Surround 5.1"
4: AC3 Surround, English, 2.0 channels, 320kbps, 48kHz
   "Stereo"
5: EAC3, French, 2/2 channels, 48kHz
   "Surround 4.0"
6: AC3, French, 5.1 channels, 512kbps, 48kHz
   "Surround 5.1"
Bitstream parsing for track 5 failed.
Demuxing this track may still produce correct results - or not.
a05 Extracting audio track number 5...
a05 Creating file "test.eac3"...
Video track 1 contains 4375 frames.
eac3to processing took 6 seconds.
Done.
Since 11,406 KB + 8,555 KB = 19,961 KB, it seems that MakeMKV extracts the non-core part of the original AC3+ stream and stores it as a full AC3+ stream in the 3D-MKV.

I don't understand why it does that. Does it make sense to store the AC3+ stream without its core? AFAIK, the "+" extension cannot be decoded without the core. Correct?

Is it a known bug of MakeMKV ? If it's the case, should BD3D2MK3D prohibit to use the AC3+ streams from a 3D-MKV container created by MakeMKV ? Or should we report that bug to the MakeMKV staff ?

Thanks in advance if someone can help me understand that mess!
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Last edited by r0lZ; 10th April 2016 at 10:55.
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