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[Help] how to extract DTS-ES 6.1
#21
It's a fake (matrixed) 7th channel. It's not comparable to DTS-HD MA 7.1 or DTS-HD MA 6.1 and the hint is in the name. DTS-ES is different from DTS-HD MA. Just to demonstrate how weird it all is: Even DTS-HD is not always lossless, for example DTS-HD HRA is a lossy extension of the base DTS-HD standard. It's a confusing mess.

Here's from Wikipedia:

Quote:DTS-ES Matrix provides 5.1 discrete channels, with a matrixed center-surround audio channel. DTS processors that are compatible with the ES codec look for and recognize "flags" built into the audio coding and "unfold" the rear-center sound from data that would otherwise be sent to rear surround speakers. DTS decoders which do not understand ES process the sound as if it were standard 5.1, and the matrixed audio for the center surround channel is output equally from the two surround speakers (very much as a sound intended to be in the centre of the sound field in a stereo recording is played equally by the left and right speakers). This is notated as DTS-ES 5.1.


You have 6 actual channels. The 7th is just a matrixed rear one.

There's also a version called DTS-ES Discrete, which actually has 7 discrete channels and the rear is NOT matrixed. Here's again from Wikipedia:

Quote:DTS-ES Discrete provides 6.1 discrete channels, with a discretely recorded (non-matrixed) center-surround channel; in home theater systems with a 7.1 configuration, the two rear-center speakers play in mono. To maintain compatibility with DTS decoders which do not support DTS-ES, the center-surround channel is also matrixed into the left and right surround channels, so that the rear center channel's sound is still present when played in 5.1 on a non-ES system; an ES decoder removes the matrixed audio from these two channels when playing back DTS-ES Discrete soundtracks. DTS-ES Discrete is sometimes notated as DTS-ES 6.1. Only a few DVD titles have been released with DTS-ES Discrete.

So unless it is the specific "Discrete" variant, there is likely no 100% standardized way of extracting the rear channel I'm afraid and we have a similar situation as with Dolby Surround/Dolby Stereo. Although maybe there is a reference implementation of it somewhere in the chips/decoders they sell.

When you convert this DTS-ES to FLAC or WAV, you will get 5.1. That is the lossless conversion. The matrixed channel is still hidden in there in the two side channels, but you don't get it as a discrete one.

Why does MediaInfo say "7 channels"? I don't know. They must have figured that's the most fool-proof way of describing the format?

With that said, it's probably a bit pointless to convert it in the first place and smarter to just keep it in the format it is, as it is smaller and reencoding will only further reduce quality (unless you're delivering as lossless).

Also, personally, I am not sure how much point there is in a 96kHz lossy DTS over a 48 kHz PCM. I doubt the frequency response is actually that great up to the Nyquist frequency (around 48kHz for 96kHz I think). You could check it with a spectrum analysis of the original or the converted 5.1 FLAC/WAV tho.
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#22
Well, I'm "forced" to convert it nevertheless, as it's from a PAL DVD - unless I would leave it untouched and speed up video to 25fps! Eek

Yes, 96kHz Vs 48kHz would be not so noticeable - not by a 40+yrs old like me, for sure; still 24bit Vs 16bit *could* be noticeable... plus, I thought to try to take the English DTS-HD MA (which is "only" 5.1), and replace its central channel with the Italian track - IF the dialogs are not outside that central channel, of course...

So, I *guess* that slowing down from 25 to 23.976fps, the matrixed channel could not behave well... maybe it will be better to extract it (before slowdown) with FreeSurround (that could works quite well in this occasion), double it and save all as DTS-HD MA (using English based or pure Italian tracks)
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#23
Ah I see.

Isn't there an NTSC DVD somewhere that also has the 6.1 ES maybe?
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#24
(2018-04-25, 03:21 PM)TomArrow Wrote: Isn't there an NTSC DVD somewhere that also has the 6.1 ES maybe?

Maybe. But, as the BD has the English track in DTS-HD MA (albeit "only" 5.1) it will eventually benefit only of the added (twin copied) central surround(s) - that, most probably, could always be added using the Italian track!
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#25
Found this info about a DTS-HD MA track:

Code:
Codec................: DTS MA / ES Matrix / Core
Bitrate..............: 3 888 Kbps / 1 509 Kbps / 1 509 Kbps
kHz/bit..............: 48.0 KHz / 24 bits
Channels.............: 8 / 7 / 6

Despite the fact it has 8 discrete channels in MA, it displays as second codec ES Matrix; may be the same with mine?

Code:
Format profile                           : 96/24 / ES Matrix / Core
Bit rate                                 : 1 510 kb/s
Sampling rate                            : 96.0 kHz / 48.0 kHz / 48.0 kHz
Bit depth                                : 24 bits
Channel(s)                               : 7 channels / 7 channels / 6 channels

I mean, first is 96/24 with possibly discrete channels, and second 48/24 ES Matrix with matrixed surround.
Dunno... Huh
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#26
Extract from the eac3to thread on doom9:

The Sonic (E-)AC3 decoder forcefully applies DRC. As a result I do not recommend to use the Sonic (E-)AC3 decoder. The current version of the Sonic TrueHD decoder doesn't work properly at all. The Sonic DTS decoder is good for DTS, DTS-ES, DTS-96/24, DTS-HD Master Audio and DTS-HD High Resolution tracks. It's quite slow, though and it decodes DTS-HD 7.1 tracks only as 5.1. Most DTS-ES and DTS-HD Master Audio 6.1 tracks are fully decoded as 6.1, though. The Nero TrueHD decoder is working perfectly fine, but is limited to 5.1 channels. The Nero (E-)AC3 works fine for most audio tracks, but sometimes DRC is still enabled, so it's not really recommended. The Nero DTS decoder ignores the additional DTS-HD information and only decodes the DTS core. The Cyberlink decoders always only output 16bit and can't be used outside of PowerDVD. So they currently do not make a lot of sense for eac3to. The libav/ffmpeg (E-)AC3 decoder works really well, but don't support 7.1 decoding yet. The libav/ffmpeg DTS decoder works well, too, but currently ignores the additional DTS-HD information, so especially DTS-HD Master Audio can't be decoded in full quality. The libav/ffmpeg TrueHD decoder works perfectly fine including full 7.1 decoding. The ArcSoft DTS decoder works well for DTS and DTS-HD decoding, but decodes many 7.1 tracks either incorrectly or with forced processing/mixing. It does support every format and channel configuration, though. The ArcSoft TrueHD and ArcSoft (E-)AC3 decoders are currently not supported by eac3to. The dcadec decoder works great for all kinds of DTS formats and channel configurations, except LBR/XSA (low bitrate) content is not properly supported yet.
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#27
I tried ArcSoft dll, but it decodes track partially, with an error; the same with lav using new eac3to version, so I strongly suspect there could be a problem during decrypting.

Where can I found the dcadec dts decoder to use with eac3to? I'd like to test it.
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#28
(2018-04-27, 02:03 PM)zoidberg Wrote: Extract from the eac3to thread on doom9:

The Sonic (E-)AC3 decoder forcefully applies DRC. As a result I do not recommend to use the Sonic (E-)AC3 decoder. The current version of the Sonic TrueHD decoder doesn't work properly at all. The Sonic DTS decoder is good for DTS, DTS-ES, DTS-96/24, DTS-HD Master Audio and DTS-HD High Resolution tracks. It's quite slow, though and it decodes DTS-HD 7.1 tracks only as 5.1. Most DTS-ES and DTS-HD Master Audio 6.1 tracks are fully decoded as 6.1, though. The Nero TrueHD decoder is working perfectly fine, but is limited to 5.1 channels. The Nero (E-)AC3 works fine for most audio tracks, but sometimes DRC is still enabled, so it's not really recommended. The Nero DTS decoder ignores the additional DTS-HD information and only decodes the DTS core. The Cyberlink decoders always only output 16bit and can't be used outside of PowerDVD. So they currently do not make a lot of sense for eac3to. The libav/ffmpeg (E-)AC3 decoder works really well, but don't support 7.1 decoding yet. The libav/ffmpeg DTS decoder works well, too, but currently ignores the additional DTS-HD information, so especially DTS-HD Master Audio can't be decoded in full quality. The libav/ffmpeg TrueHD decoder works perfectly fine including full 7.1 decoding. The ArcSoft DTS decoder works well for DTS and DTS-HD decoding, but decodes many 7.1 tracks either incorrectly or with forced processing/mixing. It does support every format and channel configuration, though. The ArcSoft TrueHD and ArcSoft (E-)AC3 decoders are currently not supported by eac3to. The dcadec decoder works great for all kinds of DTS formats and channel configurations, except LBR/XSA (low bitrate) content is not properly supported yet.

That information is outdated, I believe.

ffmpeg has switched from its original decoder to libdcadec as default. This was the original libdcadec project: https://github.com/foo86/dcadec

It has been merged into ffmpeg in 2016 or 2017, iirc, so the version in ffmpeg is likely even better than the state described in that readme.

libdcadec decodes DTS-HD MA and DTS-HD HRA (for example) perfectly and is the best current option for any decoding that I know of, much better than Arcsoft too, as it doesn't share its version-dependent errors. I researched this a while ago. It's also the most easy-to-use decoder at the same time, as it works with a simple
Code:
ffmpeg -i input_file.dts output_file.flac

I advise using FLAC as output format. If you use PCM, it seems you need to specify 24 bit manually, even if the source file is 24 bit. Don't ask me why, it's some glitch I believe.

I would guess it will also decode your DTS-ES track as 5.1, unless it is a DTS-ES Discrete track. I can try for you, if you want to send me a link to the track, spoRv.

Also, that DTS-HD MA track you showed the MediaInfo of, I interpret it like this: It's 5.1 channels in the core, with the matrixed rear channel. The MA extension then extends it to full discrete 7.1 channels.
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#29
Also, never forget that the core track in a dts file is a track to be compliant with the basic of dts decoder. So even in a 6.1 track, the core may be a 5.1 track.

We should try your steps to convert with a true discrete 6.1 dts-es from DVD, and check 8f the result has 7 single channels, and if the MediaInfo still tells 5.1 core...
"Never cut a deal with a dragon..."
- Old Shadowrun wisdom
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#30
(2018-04-27, 02:10 PM)spoRv Wrote: Where can I found the dcadec dts decoder to use with eac3to? I'd like to test it.

It's built into recent versions, but it doesn't work on your file. I did successfully decode your DTS track with Sonic, but as we expected, the output is still only 5.1.
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