Poll: Should Sony use DTS-HD Master Audio or Dolby TrueHD?

[Cinema Squid]

Originally Posted by lgans316

It's Cinema Squid the author of the widely used BDInfo utility. So it's hard to go wrong.

BDInfo only examines the basic layout and mux structure of BDs with some limited peeking at the codec headers, so my knowledge of internal codec workings is far from complete.

This discussion does make me think of another possible advantage for TrueHD over DTS-HD and that is the availability of open source implementations of the codec. It is my understanding that the implementation of TrueHD in ffmpeg is now reasonably complete and correct, which enables the construction of a number of useful supplementary tools and utilities leveraging this. Helpful certainly for a number of legitimate HTPC applications.

Contrast this with DTS-HD which is still somewhat opaque and whose exact implementation details remain closely guarded. It also seems that the popular software playback applications such as Cyberlink PowerDVD and ArcSoft TotalMedia Theater are becoming increasingly locked down with each revision such that their built-in codec implementations cannot be used outside the applications themselves.

Obviously, LPCM is the most open of the three since it is less a format at all and more a raw dump of uncompressed sample data, but if we are speaking of advantages in the compressed lossless codecs then TrueHD gets the nod on this point.

[saprano]

Originally Posted by Cinema Squid

As far as I know (and I may be wrong on some of these points - corrections are welcome!), there is no such thing as a "16-bit" TrueHD container - at least as implemented for Blu-ray. TrueHD audio headers do not contain sample bit depth information, so all samples decode to 24-bit values and samples are zero-padded in the least significant bits during decoding if the "real" bit depth is lower.

The only reliable way to determine the bit depth of a TrueHD track is to examine each sample as deado has done with eac3to to see what the minimum number of non-zero bits to represent all the samples would be. However, you can usually make reasonably informed guesses from average/peak raw bitrates to estimate 16-bit vs. something higher like 20- or 24-bit.

Things can get even more complicated, however, since you may occasionally see different effective bit depths allocated across the channels - for example, 24-bits for the fronts and 16-bits for the surrounds. The effective bit depth does not have to remain constant either, so it can vary up and down throughout the film with more or less sample LSB padding occurring in different segments.

Personally, I see this as an space-saving advantage of the TrueHD codec on Blu since, perceptually speaking, there are rapidly diminishing returns on anything above 16-bit for most of the population but the encoders can still crank up the fidelity for more challenging and dynamic segments just to be on the safe side. Those rare, blessed individuals with both golden ears and platinum equipment may disagree...

So if the bitrate stays around 1to 3mbps its probably a 16bit track, and if its 5 or higher its 24bit?

Originally Posted by deado

oh, lol. I'll shut up now

Why? you were making a point about movies using fake 24bit and you basically proved it.

what i want to know is are the studios that you said use real 24bit, lionsgate, disney, paramount, fox, and universal, doing that with all movies? obviously you dont have every single movie from them but you could test just enough to figure out if they're being consistent.

[deado]

Originally Posted by saprano

Why? you were making a point about movies using fake 24bit and you basically proved it.

what i want to know is are the studios that you said use real 24bit, lionsgate, disney, paramount, fox, and universal, doing that with all movies? obviously you dont have every single movie from them but you could test just enough to figure out if they're being consistent.

Heh, well it seems (based on what Cinema Squid says) that there is no such thing as a 16-bit TrueHD container so there isn't any faking going on, as they have no choice.

Other studios discs from my experience:

Lionsgate: A lot of the older release 7.1 tracks from Lionsgate were 16-bit (ie. 3:10 to Yuma), large majority of newer titles are 24-bit (started around the time of Saw 4).

Disney: Same as above (however some Disney 7.1 tracks are 16-bit, ie. Sleeping Beauty). Most newer Disney titles are 24-bit (ie. A Bug's Life, newest example).

Paramount: Pretty much every title is 24-bit, even old movies. ALL the Trek movies are 24-bit constant (in 7.1) and therefore take up a LOT of disc space.

Fox: Same as Paramount, however some titles have limited original information so are closer to 16-bit.

Universal: Every Blu-ray title of theirs is 24-bit, with the exception of some Studio Canal imports they use (ie. Escape from New York), or maybe some older movies.

[mugupo]

DTS was ahead of Dolby since DVD. It has more dymatic sound, lounder, more sorround effect. Dolby probably does better in music (vocals) but action should leave it to DTS.

[dobyblue]

Originally Posted by mugupo

DTS was ahead of Dolby since DVD.

Early DVD players didn't even play dts, only Dolby.

Dolby probably does better in music (vocals) but action should leave it to DTS.

Codecs don't care what genre of film or style of music they're decoding.

[Damage Inc.]

Originally Posted by dobyblue

Codecs don't care what genre of film or style of music they're decoding.

Yeah, but they do have their characteristics, no matter what is going on still.
They could still use Dolby for the lighter films, comedies, low-action, etc.
And DTS for the bigger thunderous films.
Fits the characteristics, regardless of the quality or anything like that.

[BIslander]

Originally Posted by Damage Inc.

Yeah, but they do have their characteristics, no matter what is going on still.
They could still use Dolby for the lighter films, comedies, low-action, etc.
And DTS for the bigger thunderous films.
Fits the characteristics, regardless of the quality or anything like that.

Sorry, but I don't understand how that's possible. Lossless encoders/decoders don't have any characteristics. If the audio data that comes out of the decoder is different from the audio data that went into the encoder, the process is not lossless.

[Damage Inc.]

Originally Posted by BIslander

Sorry, but I don't understand how that's possible. Lossless encoders/decoders don't have any characteristics. If the audio data that comes out of the decoder is different from the audio data that went into the encoder, the process is not lossless.

Well, there you go, maybe it's not.

Besides, if the bitrate isn't the same, how can they both be the same then?
You can't have one track for example Dolby 18mb/s and then DTS was like,
what was it, like 25mb/s, then call it the same either...
Sure, they're both "lossless" and the compression might be different.
But there must be a difference in how they work then.
Anyway, that's not my point.

The thing I meant with the characteristics isn't thát technical anyway.
People, including me, keep saying that DTS has more punch and clarity and all that.
Which is true, DTS sounds fuller, its volume is a bit higher, etc.
Those kinds of things could also be considered whether to put on this or that DVD/BD.
Again, not speaking of the quality that is, just the way the audio comes across.

[BIslander]

Originally Posted by Damage Inc.

Well, there you go, maybe it's not.

Besides, if the bitrate isn't the same, how can they both be the same then?
You can't have one track for example Dolby 18mb/s and then DTS was like,
what was it, like 25mb/s, then call it the same either...
Sure, they're both "lossless" and the compression might be different.
But there must be a difference in how they work then.
Anyway, that's not my point.

The thing I meant with the characteristics isn't thát technical anyway.
People, including me, keep saying that DTS has more punch and clarity and all that.
Which is true, DTS sounds fuller, its volume is a bit higher, etc.
Those kinds of things could also be considered whether to put on this or that DVD/BD.
Again, not speaking of the quality that is, just the way the audio comes across.

Sorry. That's all rather mystical and magical.

They're the same or they're not, which is easy to test and confirm. Tests on the data outputs show them to be identical. btw, both codecs use variable bitrates, taking whatever bandwidth they need at the moment. So, any differences in maximum bitrates have no meaning.

It sure would be helpful if anyone who hears these differences could actually point to something substantive to explain them. But, I have yet to see a single such explanation beyond dialnorm and DRC, neither of which stands up under any kind of scrutiny.

[mugupo]

In HK is the other way around, there's far more DTS sound movie than Dolby one, even their music one is DTS.

[Tok]

Originally Posted by Damage Inc.

Well, there you go, maybe it's not.

Besides, if the bitrate isn't the same, how can they both be the same then?
You can't have one track for example Dolby 18mb/s and then DTS was like,
what was it, like 25mb/s, then call it the same either...
Sure, they're both "lossless" and the compression might be different.
But there must be a difference in how they work then.
Anyway, that's not my point.

The thing I meant with the characteristics isn't thát technical anyway.
People, including me, keep saying that DTS has more punch and clarity and all that.
Which is true, DTS sounds fuller, its volume is a bit higher, etc.
Those kinds of things could also be considered whether to put on this or that DVD/BD.
Again, not speaking of the quality that is, just the way the audio comes across.

dts is able to quote a higher datarate because they are including a max data dts-HD High Resolution track in the datarate for dts-Master Audio.


if the output LPCM from the decoder equals the source LPCM. Then it really does not matter how much datarate was required.

[dobyblue]

Originally Posted by Damage Inc.

Besides, if the bitrate isn't the same, how can they both be the same then?
You can't have one track for example Dolby 18mb/s and then DTS was like,
what was it, like 25mb/s, then call it the same either...
Sure, they're both "lossless" and the compression might be different.
But there must be a difference in how they work then.

No, the only difference is in efficiency.
You can encode .flac losslessly at level 1 or level 8. Level 8 uses more compression and gives you a smaller file size than 1, but it takes longer to encode. The end result is the same, the original .wav audio file is maintained.

So too is how Dolby and dts work. All lossless compression cannot be the same.

Another example, when you .zip up a Word document. What's the size?
Now compress it using .rar, it's probably smaller...but aren't the words all still the same and in the same language when you un-rar it back to the Word document?

Hope this analogy helps a bit.

Originally Posted by Damage Inc.

The thing I meant with the characteristics isn't thát technical anyway.
People, including me, keep saying that DTS has more punch and clarity and all that.
Which is true, DTS sounds fuller, its volume is a bit higher, etc.
Those kinds of things could also be considered whether to put on this or that DVD/BD.
Again, not speaking of the quality that is, just the way the audio comes across.

Iif you're not comparing the same source the comparison is for all intents and purposes useless.

[davcole]

Originally Posted by CraigW

dts is able to quote a higher datarate because they are including a max data dts-HD High Resolution track in the datarate for dts-Master Audio.

Just for clarification's sake, I think you meant to say a CORE track. DTSHR is a totally different animal than the lossless.

I've always been curious why the even developed DTSHR, I guess it was to be able to do a 7.1 lossy encode?

[Damage Inc.]

Originally Posted by dobyblue

No, the only difference is in efficiency.
You can encode .flac losslessly at level 1 or level 8. Level 8 uses more compression and gives you a smaller file size than 1, but it takes longer to encode. The end result is the same, the original .wav audio file is maintained.

So too is how Dolby and dts work. All lossless compression cannot be the same.

Another example, when you .zip up a Word document. What's the size?
Now compress it using .rar, it's probably smaller...but aren't the words all still the same and in the same language when you un-rar it back to the Word document?

Hope this analogy helps a bit.



Iif you're not comparing the same source the comparison is for all intents and purposes useless.

I did compare films with both Dolby and DTS tracks on the same disc.
I instantly switched between them.

But if you people don't believe me, fine, be stubborn...
I'm not the only one saying it, or else I would change my mind.

[ganthc]

Originally Posted by davcole

Just for clarification's sake, I think you meant to say a CORE track. DTSHR is a totally different animal than the lossless.

I've always been curious why the even developed DTSHR, I guess it was to be able to do a 7.1 lossy encode?

That is a good question. I wonder if they were developing it in case HD-DVD won, and they needed an audio encode that would work better on the HD-30 discs. So they needed an alternative to the DD+ (1.5mbps) encode that Dolby had for hd-dvd. So like DD+, I think DTS-HDHR may go the way of the dodo bird.

[cembros]

Originally Posted by Damage Inc.

I did compare films with both Dolby and DTS tracks on the same disc.
I instantly switched between them.

But if you people don't believe me, fine, be stubborn...
I'm not the only one saying it, or else I would change my mind.

just out of curiosity which track did you compare

[BIslander]

Originally Posted by Damage Inc.

I did compare films with both Dolby and DTS tracks on the same disc.
I instantly switched between them.

But if you people don't believe me, fine, be stubborn...

Which discs with dts-MA and TrueHD did you compare? Did you level match the outputs to remove volume differences from the equation? Were these blind tests or sighted?

It's not a matter of being stubborn. Your observations are not consistent with the science or engineering involved here. Under those circumstances, it seems prudent to ask whether there are other factors beyond the codecs that would account for the observed differences. That's where these discussions tend to break down. All too often, the subjectivists bail to the place where you seem to have landed - you hear what you hear and you really don't seem interested in figuring out why that might be the case.

I'm not the only one saying it, or else I would change my mind.

You base what you hear on what others hear? Really?

[Damage Inc.]

Originally Posted by BIslander

Which discs with dts-MA and TrueHD did you compare? Did you level match the outputs to remove volume differences from the equation? Were these blind tests or sighted?

It's not a matter of being stubborn. Your observations are not consistent with the science or engineering involved here. Under those circumstances, it seems prudent to ask whether there are other factors beyond the codecs that would account for the observed differences. That's where these discussions tend to break down. All too often, the subjectivists bail to the place where you seem to have landed - you hear what you hear and you really don't seem interested in figuring out why that might be the case.

You base what you hear on what others hear? Really?

Oh don't be so childish, you know what I mean.
Wait, you don't, or else you wouldn't react this way would you.
I'm done here, I'm just telling my experience with the differences.
But everyone just rambles over it in disbelief, so bye.

[davcole]

Originally Posted by ganthc

That is a good question. I wonder if they were developing it in case HD-DVD won, and they needed an audio encode that would work better on the HD-30 discs. So they needed an alternative to the DD+ (1.5mbps) encode that Dolby had for hd-dvd. So like DD+, I think DTS-HDHR may go the way of the dodo bird.

Right now it doesn't seem to have a use, however DD+ may find itself a home in some internet and satellite download services.

[aygie]

Has Alexander J chimed in on this? That would be interesting, as he has used DTS HD MA 7.1 on pretty much all his titles.