[FFmpeg-devel] [PATCH] Possible fix for h.264 HDDVD playback

madshi dear
Fri Jan 18 12:45:19 CET 2008

Nico Sabbi schrieb:
> Il Friday 18 January 2008 12:30:10 Ian Caulfield ha scritto:
>> They mux both the TrueHD stream and an AC3 stream of the same track
>> on one PID - I think the idea is that players that can't decode the
>> TrueHD can decode the AC3, but it seems pretty retarded to me...
>> Ian
> I wonder what those people drink during standarditazion commitees.
> maybe water is even banned

 From a technical point of view it is kind of ugly. However, it does 
have some
nice usability effects: There's only one audio track to choose for every 
Blu-Ray players which can decode TrueHD automatically decode TrueHD for
HDMI output and ignore the AC3 frames, while they can use the AC3 frames
for SPDIF output. Players which cannot handle TrueHD make use of the AC3
frames in the track while ignoring the TrueHD packets. This is 
comfortable for
the end user. If there were two separate tracks, the end user would have to
decide which track to use and maybe even think about which track is better
for the transport (SPDIF vs analog vs HDMI). And you can bet on that many
end users don't have a clue what the difference is between TrueHD and AC3.
So having both TrueHD and AC3 in one track hides the dirty details from the
end user while still giving him the best possible quality he can 
possible get
with his hardware and connection.


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