Shazam 2 - Fury of the Gods - Audio Bitrate Question

[mike_mgoblue]

In Shazam 2: Fury of the Gods, the first audio track is the default Audio track - the lossless Dolby TrueHD Atmos 7.1. There is no confusion about this.

There is also no confusion regarding the fourth Audio Track - the Dolby Digital 5.1 Commentary that has a bitrate of 640kbs. This fourth Audio Track is for the visually impaired. And the fifth Audio Track is a form of Commentary with the makers of the movie.

But there are some confusions about what is the secondary Dolby Digital 5.1 Audio Track nd the third Dolby Digital 5.1 Audio Track. In particular, the secondary Audio Track is a 5.1 Audio Track with a bitrate of 448kbs. The third Audio Track is a 5.1 Audio Track with a bitrate of 640kbs. These two tracks of 448kbs and 640kbs sound identical and seem to have no differences. I'm just wondering if anyone knows what any difference might be between the 448kbs Audio Track #2 and the 640kbs Audio Track #3?

[dcoke22]

The lossless formats, Dolby TrueHD and DTS-HD MA, include a 'core' lossy audio track. Theoretically players that can't understand the lossless formats will be able to find and understand the older and more widely supported lossy core formats.

MakeMKV separates the lossless format from its lossy core. Almost always this means if the main audio track is a Dolby TrueHD, the second audio track is the lossy Dolby AC-3 core from the TrueHD track. In modern movies, these are often encoded at 448kbps. On older movies they were encoded at 640kbps (the limit of Dolby AC-3).

I don't know what the 3rd audio track is. Perhaps it is there as an extra audio track for maximum compatibility with players that can't find the lossy core of a lossless track?

[mike_mgoblue]

The lossless formats, Dolby TrueHD and DTS-HD MA, include a 'core' lossy audio track. Theoretically players that can't understand the lossless formats will be able to find and understand the older and more widely supported lossy core formats.

MakeMKV separates the lossless format from its lossy core. Almost always this means if the main audio track is a Dolby TrueHD, the second audio track is the lossy Dolby AC-3 core from the TrueHD track. In modern movies, these are often encoded at 448kbps. On older movies they were encoded at 640kbps (the limit of Dolby AC-3).

I don't know what the 3rd audio track is. Perhaps it is there as an extra audio track for maximum compatibility with players that can't find the lossy core of a lossless track?

I know what you are talking about. For example, with DTS sound it may say, "Lossless 4,600kbs" and "Lossy 1,509kbs" as Audio Track 1 for DTS-MA, and then Track 2 will be DTS and simply say "1,509kbs."

This particular Shazam movie isn't like that, though. Audio Track #1, #2, and #3 are all identical in terms of their content. #4 is a 640kbs that is meant for disabled people the way it describes everything in the background. And #5 is a Special Feature with the people who made the movie.

I looked at Audio Track #1. It says "Dolby TrueHD." And it does say, "Lossless, Lossy." It says the Bitrate is "Variable." It gives the overall Bitrate, but it doesn't give the Bitrate for the "Lossy" format.

Audio Track #2 is 448kbs and is "Lossy." Audio Track #3 is 640kbs and is "Lossy." The content is 100% identical, just like when you compare them to Audio Track #1. It is the equivalent of having Audio Track #2 of a DTS be 1,509kbs, but have a Track #3 be 768kbs with both being identical content. It is very unusual. That is why I'm wondering why it is like that.