Remove lossy core?

[marcusj0015]

Can I remove DTS HD MA core and remove core from TrueHD too? AKA can I just keep the high def lossless sound and throw away the lossy parts?

[Sparktank]

MakeMKV allows you to select just the HD audio tracks. It's free while in BETA.
DVDfab also allows you to select the HD audio tracks.

In most programs, just select the HD audio track.
The lossless HD audio tracks contain the Core internally at all times.
Just some programs will let you select two formats: HD audio or the Core.

DTS-HD MA/TrueHD will always have the Core embedded, but it will not effect the file size.

In programs like MakeMKV, you'll see that it allows you to choose several formats for the audio.
-Lossless HD audio
--Core audio
-Lossless HD audio (different language)
--Core audio (different language)
-AC3@640 (core without the HD audio)
-AC3@xxx bitrate (AC3 audio for commentary/foreign language/etc without the HD audio)

[Gser]

There is no lossy core in TrueHD and no you can't take out the lossy part from DTS HD-MA because the lossless part is "added" on top of the lossy part.

[SassBot]

Can I remove DTS HD MA core and remove core from TrueHD too? AKA can I just keep the high def lossless sound and throw away the lossy parts?

You can't remove the lossy core from a DTS HD MA unless you don't want the file to work anymore. The lossless part is a bitstream extension to the lossy core. Both pieces are needed.

[ramicio]

There IS support for lossy cores in TrueHD, most soundtracks employ it, and you CAN indeed strip away the core to be left with just the lossless portion. You can't do squat about DTS-HD Master but capture the lossy core.

eac3to <input crap> output.thd+ac3

...would just copy literally the source.

eac3to <input crap> output.thd

...would give you the lossless portion only.

eac3to <input crap> output.ac3

...would give you the lossy core

eac3to <input crap> output.dts -core

...would give you the lossy core of the DTS-HD Master track.

Please try to fix the blank lines after the single line of code. It's sloppy looking, as is also everything on the Internet removing double spacing after a period or other sentence-ending punctuation.

[marcusj0015]

There IS support for lossy cores in TrueHD, most soundtracks employ it, and you CAN indeed strip away the core to be left with just the lossless portion. You can't do squat about DTS-HD Master but capture the lossy core.

eac3to <input crap> output.thd+ac3

...would just copy literally the source.

eac3to <input crap> output.thd

...would give you the lossless portion only.

eac3to <input crap> output.ac3

...would give you the lossy core

eac3to <input crap> output.dts -core

...would give you the lossy core of the DTS-HD Master track.

Please try to fix the blank lines after the single line of code. It's sloppy looking, as is everything on the Internet removing double spacing after a period or other sentence-ending punctuation.

Thank's man, just what I was looking for. :D

[SassBot]

There IS support for lossy cores in TrueHD, most soundtracks employ it, and you CAN indeed strip away the core to be left with just the lossless portion.

Except it's not a lossy "core". It's AC3 frames interleaved into the TrueHD track. The TrueHD track has no dependence on those AC3 frames. This is different to DTS HD MA which requires both the lossy core + lossless extension to decode properly.

[ramicio]

What's your point? It's still a lossy track to fall back to. Who cares about the computational method they use to pair the two into one space? To the consumer, who has ZERO need to separate the two, they are the same damn thing.

[SassBot]

Because for what he wants to do the distinction makes a big difference? Stripping out those AC3 frames from a TrueHD track doesn't have any effect on the TrueHD part. Stripping out the "core" of a DTS HD MA track leaves it broken since you can't decode it just from the lossless extension which is what the OP assumed he could do.

AKA can I just keep the high def lossless sound and throw away the lossy parts?

[ramicio]

THERE IS NO SUCH THING AS STRIPPING THE CORE FROM A DTS-HD MASTER TRACK AND BEING LEFT WITH A LOSSLESS SHELL!!! Why are you harping on this? No one else here offered any help, you just gave your opinion on semantics.

[Asmodian]

Except it's not a lossy "core". It's AC3 frames interleaved into the TrueHD track. The TrueHD track has no dependence on those AC3 frames. This is different to DTS HD MA which requires both the lossy core + lossless extension to decode properly.

Thanks for this clarification; I had assumed both DTS HD MA and TrueHD worked in a similar way. It is interesting and unexpected to me to know TrueHD has no dependence on on the AC3 portion. That seems pretty wasteful of bits but I guess they do not care about that too much on a bluray.


THERE IS NO SUCH THING AS STRIPPING THE CORE FROM A DTS-HD MASTER TRACK AND BEING LEFT WITH A LOSSLESS SHELL!!! Why are you harping on this? No one else here offered any help, you just gave your opinion on semantics.

He was just pointing out the difference between the two, the helpful command lines you gave were great but you didn't point out that you couldn't strip the DTS-HD lossless without its lossy core (just didn't include a command for it). More information is almost never a bad thing, surely not in this case. The difference between "core" and "interleaved AC3 track" is not at all too subtle to point out on Doom9.

[ramicio]

the helpful command lines you gave were great but you didn't point out that you couldn't strip the DTS-HD lossless without its lossy core (just didn't include a command for it).

Excuse me? Did you read my post?

You can't do squat about DTS-HD Master but capture the lossy core.

[Asmodian]

Ah, Sorry I missed that line, still the difference between "core" and "interleaved AC3 track" is not at all too subtle to point out on Doom9.

[ramicio]

Again, it's just BS semantics. The comments about it were completely pointless in this context because they offered no help and gave completely horrible information.

[hello_hello]

Thanks for this clarification; I had assumed both DTS HD MA and TrueHD worked in a similar way. It is interesting and unexpected to me to know TrueHD has no dependence on on the AC3 portion. That seems pretty wasteful of bits but I guess they do not care about that too much on a bluray.

I agree. I knew how DTS HD MA worked, and thanks to this thread I now know how TrueHD works, and as you said it's a distinction which many doom9 members would prefer to understand.

[ramicio]

It's not interesting when it has nothing to do with the case at hand, and the fact that it offers no useful information for helping the OP reach their goal.

[Ghitulescu]

It is interesting and unexpected to me to know TrueHD has no dependence on on the AC3 portion. That seems pretty wasteful of bits but I guess they do not care about that too much on a bluray.
Since TrueHD had no "lossy core", and Blu-ray wagon was already on its track, something had to be done for the players that could not decode TrueHD (first gen, and most of 2nd one). The solution was to embed an additional AC-3 track (what's 600MB on a BD25?). Old players played the AC-3, new ones the THD.[/QUOTE]

Again, it's just BS semantics. The comments about it were completely pointless in this context because they offered no help and gave completely horrible information.
It's not BS semantics at all. It is a very important technical difference. Like the coconut vs. a cherry. One can extract the kernel of a cherry, but not from the coconut, as the coconut is itself the kernel.

[ramicio]

It's BS semantics...pure and simple. DTS-HD Master and its core operate the same exact way. Things that cannot decode the master will decode the core. TrueHD operates the same way. The only difference is that it can operate without a core. It doesn't makes its core not a core.

[Chetwood]

It's not BS semantics... pure and simple.

[ramicio]

It is BS semantics, pure and simple. It had zero to do with the thread at hand.

[Ghitulescu]

TrueHD operates the same way.Nope. In the absence of an additional AC-3 track, the players that cannot decode THD will remain mute. Those that cannot decode DTS-HD should at least decode its lossy core (added since the DVD technological age).

[ramicio]

Show me a title where that actually exists... If there was a title like that, it would have other sound tracks and would just decode them.

[Ghitulescu]

Show me a title where that actually exists... If there was a title like that, it would have other sound tracks and would just decode them.

Nobody can show you this because the titles we have access, as consumers, come on Blu-rays, and on these it is mandatory to have the AC-3 supplementary track to each THD one.

People that want the lossy part of any HD format simply demux the AC-3 tracks (or get the DTS-core). Those that need HD audio instead, eg in FLAC, they could use the DTS-HD MA tracks, or, alternatively, the THD one (not the THD+AC3).

[ramicio]

Exactly, so it doesn't apply, and your whole argument just falls apart.

[Ghitulescu]

Exactly, so it doesn't apply, and your whole argument just falls apart.

No, because once one remuxes the movie into MKV by keeping eg only the HD audio (DTS-HD MA and THD), that one can easily recover a lossy part from the DTS-HD (a simple demux) but he cannot get the lossy part from THD (unless he downconverts the HD audio).

[ramicio]

Which applies to what? You're making less sense as time goes on.

[kolak]

TrueHD and DTS-MA do not work in exactly the same way even if the end effect for the end user is the same. You keep saying that they do, because you care only at end effect. People on doom9 look way deeper than just end effect- they are not a "average" consumers- they like to know how things work. It has been described quite well how TrueHD and DTS-MA work, what is the same, what is different. Your post in majority just spam this thread.

Ghitulescu post from above makes perfect sense.

[ramicio]

Again, it has no bearing on what the OP was looking for.

[LoRd_MuldeR]

I think it's time to close this thread :rolleyes: