Page 3 of 3

Re: Multiple audio tracks with different codecs and languages

Posted: 13 May 2019, 12:08
by rednoah
I've never seen a Title field for an audio stream:

Code: Select all

Title                            : Dolby Digital Plus Audio / 7.1 / 48 kHz / 1280 kbps
I guess this Title tag is supposed to show up when you select a given audio stream in your media player. Someone thought this is a good display value for this audio stream.

Might be useful, but probably won't be defined for the vast majority of files.

Re: Multiple audio tracks with different codecs and languages

Posted: 13 May 2019, 12:47
by devster
My assumption was that the "title" field is an optional metadata tag and I wouldn't want to rely on it.

For naming purposes I found out that the AdditionalFeatures bascically means a hybrid stream.
In this case there seem to be:
  • "base" 5.1 AC-3 stream, decodable by an AC-3 decoder. (The Format field which represents the "minimal" decoder required)
  • Dependant E-AC-3 stream with 2 additional channels, optional and apparently interleaved with the first one (The Format/String apparently)
It seems to be part of E-AC-3 which allows embedding a core AC-3 stream.

The ChannelPositions/String2 seems a bug, a workaround in this specific case would be to tokenize by comma ChannelPositions (Front: L C R, Side: L R, Back: L R, LFE), strip whatever's before the colon, count number of words in the string (3,2,2,1) with the last one being the Low Frequency Effects.