Atmos vs 5.1

[Owen Smith]

I've been using it for over 15 years. Since first came out... I know!

I've been using Windows for well over 15 years, but I know little about its internals. I know people who have been driving for decades and know nothing about how cars work.

 

[SeeMoreDigital]

I've been using Windows for well over 15 years, but I know little about its internals. I know people who have been driving for decades and know nothing about how cars work.

With respect that's a very poor analogy, Windows is not just an OS, it offers a huge amount of functionality. Cars incorporate thousands of different technologies and engineering challenges. The tyre technology alone is mind blowing!

Essentially MakeMKV is a re-muxer that also offers disc decryption. It looks at the streams on a DVD or Blu-ray, it decrypts the streams, it de-muxes the streams and it re-muxes the streams into the .mkv container. It does not offer any encoding functionality. It's why it's easy to use.

Other re-muxing softwares such as MKVtoolNix and TSmuxer don't offer any encoding functionality either!

That being said, if you don't believe somebody who's been using it for over 15 years, I suggest you visit the MakeMKV website, read through their documentation and use their software.

 

[barfle]

Would it be possible to encode 7.1.4 Atmos, 1kHz at each of the 11 locations in turn (.1 not needed) and then report where each of these 11 locations ends up appearing in the Dolby Digital 5.1 downmix (using the downmix defaults)?


Kirk Bayne

As I understand Atmos (imperfectly), the overheads are not channel-based, so although it would be possible to locate an object so it coincided with a speaker location, it would come out different for different installations. I’ll find out more once I get my new hardware in and read the manuals (I hope).

 

[LuvMyQuad]

And how do you know that? Is that what the documentation says, or have you looked at the source code? Not disputing what you say, just asking for your source.

Edit: thinking about it, if MakeMKV can pull a stereo, 5.1 or 7.1 track out of a bunch of TrueHD substreams that rely on and cross reference each other, it must be doing some level of TrueHD decoding to understand all that substream information.

So you think Dolby would license a software decoder to an enterprise that specializes in decrypting and ripping copyrighted material from DVDs and blurays. And in addition, makeMKV pays for this decoding capability and then gives it away freely.

Either the TrueHD streams do not "rely on and cross reference each other" or there is some kind of script embedded in the streams themselves that facilitates thier reconstruction. My guess is the former.

Another question. If the 5.1 AC3 stream in the TrueHD stream is meant to provide compatability for older systems that predate all this processing magic, how is that stream constructed? That 5.1 AC3 stream will play over an optical digital connection into equipment with no advanced Atmos or TrueHD decoding of any kind. Equipment that is 25 years old!

 

[ssully]

Flush and 'fold'. Still sounds like shit to us. Folded DOWN to 7.1...and then 5.1. Wonderful! Half ass is great? Again.. We do NOT have an atmosT amp or receiver. Atmost is NOT designed to work properly without it and the minimal recommended speaker set up.. And it sure doesn't

This is nonsense.

*Every* Dolby surround mix is back-compatible with ancient AVRs that only do Dolby Digital AC3. Even if your AVR doesn't decode Atmos, doesn't decode Dolby TrueHD, doesn't decode Dolby Digital+, Doesn't decode Dolby Digital EX --- there will, as has always been the case, still be a good old (lossy) DD 5.1 'core' embedded in there, and your 5.1 system will default to that, as long as there is a Dolby logo on your AVR.

(My AVR can do all of those, but I don't have an Atmos speaker setup, I ahve 5.2 (2 subs). All Atmos discs have a 7.1 bed mix. Some also add a dedicated 5.1 mix. If I play the 7.1 mix it folds down to 5.1. If I play the 5.1, well duh, it just plays it.)

So what exactly are you talking about? If your 'Atmos sounds like shit' and you have the most bare bones DD setup, then your complaint is about technology Dolby has been using for decades, not about Atmos.

 

[ssully]

I've been using Windows for well over 15 years, but I know little about its internals. I know people who have been driving for decades and know nothing about how cars work.

MakeMKV is not decoding anything.

(*Decrypting*, well...)

Think of MakeMKV as (among other things*) a tool for preparing your BluRay for ripping tracks with, e.g., DVD Audio Extractor -- which actually can decode Dolby and DTS audio into PCM files, if you want it to. Otherwise, decoding happens in your AVR or playback software.)


(*You can also use it to simply re-create your disc as a giant file, but now without encryption. You can play that file too, like a disc image. Again, the decoding would happen in your AVR or software audio player)

As part of its process MakeMKV has to analyze the data on each stream present on the disc. That's how it can tell you stuff about channel number, format, placement, etc.