I'm trying to determine what the format is of audio tracks stored in iTunes HD movie downloads. For example, on the iTunes store page for "Star Wars: The Force Awakens" (https://itunes.apple.com/gb/movie/star-wars-the-force-awakens/id1063948707) the audio language is listed as "English (Dolby 5.1, Subtitles, CC), which I would expect to be something like a Dolby AC-3 track. However, after downloading, mediainfo lists the audio track as:
Audio #1
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 2h 18mn
Source duration : 2h 18mn
Bit rate mode : Variable
Bit rate : 160 Kbps
Maximum bit rate : 269 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 156 MiB (3%)
Source stream size : 156 MiB (3%)
Title : Core Media Audio
Language : English
Encoded date : UTC 2016-03-22 15:35:19
Tagged date : UTC 2016-03-22 15:36:39
Encryption : iTunes
Is this how audio tracks for iTunes HD movies are provided, as something like an AAC-encoded Dolby Pro Logic II, which doesn't feel like a genuine representation of saying the language is Dolby 5.1? Or is something amiss here with my download?
This turned out to be the result of using mediainfo on a still-encrypted version of the file, to which it presumably can't determine the audio encoding correctly. It works as expected and shows a Dolby Digital 5.1 track during playback.