DCA with variable channels/format

[shekh]

How common are such files?
Can somebody share an example?
I got one but it is all mute (not interesting).

ffprobe output looks like this:


media_type=audio
stream_index=1
key_frame=1
pkt_pts=19334
pkt_pts_time=19.334000
pkt_dts=19334
pkt_dts_time=19.334000
best_effort_timestamp=19334
best_effort_timestamp_time=19.334000
pkt_duration=10
pkt_duration_time=0.010000
pkt_pos=5318875
pkt_size=2012
sample_fmt=fltp
nb_samples=512
channels=6
channel_layout=5.1(side)

side_data_type=AVMatrixEncoding
side_data_size=4



media_type=audio
stream_index=1
key_frame=1
pkt_pts=19345
pkt_pts_time=19.345000
pkt_dts=19345
pkt_dts_time=19.345000
best_effort_timestamp=19345
best_effort_timestamp_time=19.345000
pkt_duration=10
pkt_duration_time=0.010000
pkt_pos=5318875
pkt_size=2868
sample_fmt=s16p
nb_samples=512
channels=8
channel_layout=7.1

side_data_type=AVMatrixEncoding
side_data_size=4

[sneaker_ger]

Not uncommon on Blu-ray.

https://www.sendspace.com/file/pqmqwx (core/es)
https://www.sendspace.com/file/cua5w1 (core/es/ma)

/edit:
It seems my samples are actually something else. MediaInfo shows multiple layouts incl. 5.1 but ffprobe always says channels=7
channel_layout=6.1
Either one them is wrong or there are different ways to store multiple layouts (downmixing?). :confused:

[shekh]

Yes, your samples appear as single format when decoding.
I suspect that my sample was actually result of some mistake.

[sneaker_ger]

Yes, maybe. You could create e.g. 5.1 and 7.1 and just binary concat them and get such files but are they allowed on Blu-ray? Probably not. Any TV channels using DTS? If you can find switching layouts it's usually only on TV.

[shekh]

Thanks for hint, I concatenated your samples and at least VLC is happy with it :)

[tebasuna51]

@sneaker_ger
Your samples are DTS-ES, 6.1 both, the second with MA extension.

Maybe this one (MA 7.1, core 5.1): https://www.sendspace.com/file/tpumwx

Concat different channels layouts is not recommended, in BluRay must be in different m2ts.

[sneaker_ger]

No, ffprobe will show "channels=8" only. It's the same as my samples.