Quality of converted LPCM to DTS-HD

[avr1910]

Hi people,

I have a copy of Fifth element with both Dolby TrueHD an LPCM 5.1. With eac3to i have extracted LPCM to mono wavs and encoded it to DTS-HD MA. I know that LPCM i uncompressed and should be of better quality compered to Dolby and Dts solutions. Is it possible that this Dts encode from LPCM could be better than TrueHD track on bluray disk?
I know that probably somebody will think this is stupid but i have nothing better to do:D

O and, is it possible to get 5.1 LPCM output from mpc-hc trough HDMI to receiver. There is no problem with truehd and dtshd but LPCM only goes out in stereo.

[Inspector.Gadget]

Lossless is lossless.

If you have a TrueHD decoder and DTS-HD encoder without any bugs, then the sound of each will be identical (provided you didn't do something dumb like map the channels in the wrong order).

Is it possible that this Dts encode from LPCM could be better than TrueHD track on bluray disk?

No. So many people inexplicably buy into the DTS hype. It's even less relevant where all involved compression schemes are LOSSLESS.

[Blue_MiSfit]

It's possible that the two tracks were mastered differently, but other than that you shouldn't see any differences, *ASSUMING EVERYTHING IS SET UP CORRECTLY*, as Inspector.Gadget said.

Derek

[avr1910]

Ok guys, thanks for that. I noticed how practically every new BR release feature dts-hd track but not truehd one. I would say that every 1 out of 10 releases feature truehd track so i thought that it should be better, maybe i am wrong.

[mindbomb]

Assuming the bit depth is the same, lpcm, truehd and dts-hd ma are all the same in terms of quality.
In a related note, you should check if the bit depth is the same.

[rik1138]

Ok guys, thanks for that. I noticed how practically every new BR release feature dts-hd track but not truehd one. I would say that every 1 out of 10 releases feature truehd track so i thought that it should be better, maybe i am wrong.

No, if done properly either one of them should be identical...

As for DTS's popularity over Dolby, it's just a simple matter of convenience... The DTS encoder is faster and cheaper than the TrueHD encoder. TrueHD was an absolute nightmare to try to make work with any kind of multi-angle or seamless branching (I understand they've improved this, but a little too late...)

And, from a production standpoint, the _ENTIRE_ Blu-ray production work flow is PC based, except for graphics creation (which can be PC or Mac). For some reason, the TrueHD encoder is only available for Macs. So every compressionist, author, etc in the Blu-ray field would have to get another computer just to use the software (or run Windows on a Mac)... When there's a cheaper, faster and better (from a usage standpoint) solution waiting, why bother?

It was the seamless branching thing that really killed them though... It took nearly 36 hours to encode TrueHD audio for seamless branching for 45 minute episode! Of a 3-season TV show, that was going to take _WAY_ too long... The DTS software created a perfect DTS HD-MA file in around an hour. And it's even faster now... (Haven't used Dolby in a while, so not sure how much they've improved.) WB finally switched over simply because of their 'Maximum Movie Mode' features which were nearly impossible to do with Dolby...

[avr1910]

Thanks rik1138, great explanation, one that makes sense to me and couldn't find it elsewhere. As for the coding speed, 6 channel lpcm file was converted to dts-ma format in about 20 minutes on my old Athlon X2 @3250 mhz, im quite happy about it.

[ACrowley]

. It took nearly 36 hours to encode TrueHD audio for seamless branching for 45 minute episode! Of a 3-season TV ...
Yes i know, but theres a new Dolby Media Encoder SE Update v1.3.8 which has significant improved TrueHD Encoding Perfomance. Its by far faster as the old v1.3.5.
However, DTS HD MA Suite is still faster :

[rik1138]

Yes i know, but theres a new Dolby Media Encoder SE Update v1.3.8 which has significant improved TrueHD Encoding Perfomance. Its by far faster as the old v1.3.5.
However, DTS HD MA Suite is still faster :

Keep in mind, this isn't just TrueHD encoding in general, it's encoding for seamless branching... Has that been improved? That's what made it take so long... Just encoding the 45 minute episode as one piece took half the time. But in order to segment it properly to allow seamless branching is what made it take so long... And, at that time, the TrueHD stream had to be encoded with one tool, and the AC3 stream with another (still segmented to match the branching pieces).

And it still won't run on any of the computers we use for Blu-ray production... :cool: (Although, funnily enough, the tool they gave me to do seamless branching _was_ PC based... So they have a PC version of the encoder, they just won't develop it or release it for some reason...)

I'm sure they've improved the software a lot, and I know they've added the seamless capabilities (but I haven't tried them out), but it just seems like it's a little too late... Once every studio wanted to do something with seamless branching, and Dolby really couldn't do it (or, at least not very easily), they just went to DTS... They should have focused on making that work much earlier if they wanted to compete.

[ACrowley]

Keep in mind, this isn't just TrueHD encoding in general, it's encoding for seamless branching... Has that been improved? That's what made it take so long... Just encoding the 45 minute episode as one piece took half the time. But in order to segment it properly to allow seamless branching is what made it take so long... And, at that time, the TrueHD stream had to be encoded with one tool, and the AC3 stream with another (still segmented to match the branching pieces).

And it still won't run on any of the computers we use for Blu-ray production... :cool: (Although, funnily enough, the tool they gave me to do seamless branching _was_ PC based... So they have a PC version of the encoder, they just won't develop it or release it for some reason...)

I'm sure they've improved the software a lot, and I know they've added the seamless capabilities (but I haven't tried them out), but it just seems like it's a little too late... Once every studio wanted to do something with seamless branching, and Dolby really couldn't do it (or, at least not very easily), they just went to DTS... They should have focused on making that work much earlier if they wanted to compete.

Yes, youre right. However, v 1.3.8 TrueHDencoding Perfomance is acceptable and not so far from DTS HD MAS Suite. Its really a lot faster no with the updste

by the Way.. alot of (the Most i think) Audio Production including Audio for BluRay comes from Mac Workstations, and Video comes more from Windows (Sonic,Netblender..)
I dont think Dolby cares alot about Hobby Users theyre using PCs :)

Ive the Feeling you dont like Macs generally ?:
However...

[kieranrk]

If the Media Encoder is anything like other products, it probably has no simd at all.

[rik1138]

by the Way.. alot of (the Most i think) Audio Production including Audio for BluRay comes from Mac Workstations, and Video comes more from Windows (Sonic,Netblender..)
I dont think Dolby cares alot about Hobby Users theyre using PCs :)

I'm not talking about hobbyists... I do this for a living working with the major studios, and Dolby/DTS directly.

Audio production is done on Macs, sure... But audio engineers/editors/Pro Tools users/etc aren't the ones that _encode_ the audio for Blu-ray. They deliver their final files to the Blu-ray facility. In every facility I've worked in, DVD and Blu-ray development is it's own dept. That department captures the video/audio off of tape (onto PCs), encodes the video and audio to the format of the disc (on PCs), delivers it to authoring (which is on PCs). There are absolutely _NO_ Mac computers in the professional Blu-ray/DVD workflow. If the facility I worked in didn't do graphics, they usually wouldn't even own a Mac... Even the DVD version of the Dolby encoder was PC based. To date, the company still hasn't actually given me a _reason_ for not developing the PC version of the encoder... And it's definitely part of the reason why they lost a lot of the market share. I know of a couple of facilities that bought the Dolby encoder before realizing they couldn't even use it (no Macs). I don't get the 'logic' of not developing it for both systems, especially when the MLP encoder was originally written for PCs... All they had to do was give it the Dolby user interface.

Ive the Feeling you dont like Macs generally ?:
However...

Don't have an opinion on them one way or the other... Seem like good computers, cool interface, etc... Just never really used them (unless I _have_ to encode TrueHD audio... :) ). This has nothing to do with my opinion of either computer... It's simply the fact that they made software for a computer that isn't heavily used by their target market.

[Blue_MiSfit]

Yeah... Media Encoder (or maybe it was Media Producer) was pretty bad last I used it, which was almost a year ago.

Their dedicated encoding systems like the DP600 are much better designed, and can integrate into a lot of different workflows easily. For me, it's a much better fit.

Speeds are obscenely slow compared to open source tools like Aften (in eac3to), with the latter being something like 10 times faster. Granted, the DP600 has the capability to analyze the audio, do loudness correction, and set all the Dolby metadata correctly instead of not setting it at all or just guessing as seems to be the place everywhere else.

How much that really matters, I'm not totally sure. I do know that in the tests I did with surround-heavy material, their E-AC3 encoded stream at 256kbps sounded noticeably better than an Aften encoded AC3 stream at 384kbps.

/shrug it's DOLBY (tm) ;)

Derek

[Ditto666]

The focus on this site is mainly the codecs and formats themselves and not really on what plays the products of these things back. Where some of the differences come in is there. What does "support for DTS-HD, Dolby TrueHD" on a receiver actually mean? It means that they have in them NOT just the capability to play the audio back (which is actually what happens with LPCM, aside from general built-in additional functionality), but to decode the audio using the matrix designed by the company for the balancing, distribution, and dynamics of the sound afterward, based on the input it's receiving. "The quality" is in fact the same but for instance, the differences between a media device like the PS3 decoding the audio and having the audio sent straight to the receiver are existent. Some receivers simply fail at doing this right because of interfering functionality but for the most part, what the hype is actually about is just this. I can't give you specific technical details about how that works, but, if that were put aside at least for a second to begin with, and trust was given to these wonderful things called ears, then none of this clever talk would've existed. Not that it all isn't relevant, it very much is, but unless you actually designed the darn thing, you will never know enough technically to see all of what affects the actual end result.

A more involved example of what I'm talking about is DTS-ES, which I'm noticing Disney Pixar movies are using commonly like UP and Toy Story 3. It can be and in these cases is a 6ch format that is engineered to work with the DTS-ES supported functionality in receivers to upmix to 6.1 (7ch), using the designed matrix.

[dansrfe]

Personally, if any "real man" company actually supported FLAC bitstreaming and there was a FLAC bitstreamer in ffdshow because of that, all of my problems of wasting space and sometimes having to go through a long ass extraction and then a long encoding time in dts hd encoder would be eliminated. FLAC beats everything. All other lossless codec bitc**s bow down.

[Blue_MiSfit]

Yeah... except FLAC isn't supported by BluRay :)

If you must have lossless audio, then Dolby TrueHD or DTS-HD MA are your only choices.. or PCM but you're a clown if you choose that!!!

Derek

[nixo]

If you must have lossless audio, then Dolby TrueHD or DTS-HD MA are your only choices.. or PCM but you're a clown if you choose that!!!

Derek

At least for multichannel. I've seen Blu-rays with 16-bit stereo DTS-MA tracks encoded with a 1536 kbit/s core, making the DTS tracks a good bit bigger than equivalent PCM. That's just bizarre.

--
Nikolaj

[Midzuki]

At least for multichannel. I've seen Blu-rays with 16-bit stereo DTS-MA tracks encoded with a 1536 kbit/s core, making the DTS tracks a good bit bigger than equivalent PCM. That's just bizarre.

Not "bizarre", just completely insane ¬¬
510kbps is "transparent enough" for 16-bit stereo.