eac3to - audio conversion tool

[Etroxamin]

it might have been discussed here already, i would guess, but i only found little information about it:

when i demux a normal .dts file (in this case a 320kbps 2.0 dts track) eac3to says: patching dts to 24 bits.
mediainfo tells me the dts track inside m2ts file is 16 bit, there is a switch: -dontpatchdts - if I use it i get a file of the same size (down to the last byte). However on a wiki i read that -dontpatchdts switch applies a dither.

will this switch really apply a dithering to a normal .dts file?
and is the patching to 24 bit change anything else than a metaflag change somewhere inside the dts file?

as far as i have understand it, lossy audio usually dont have a bit depth at all, but for some reason a dts file has a flag, to be able to be copied to an audio disc, as there are also some dts audio tracks and it seems to be mandatory to have that flag on a audio disc.

actually i would like to keep the 16 bit flag, even if it doesnt change anything, that 24 bit however would just be pointless if i can demux it without that 24 bit patching, and without damaging the file of course (which would be the case with dithering in same way). As this whole patching thing amplifies the uselessness of that information, i think.

But for dithering i would expect that eac3to needs to reencode the file, but with the -dontpatchdts switch, eac3to just says extracing track. it takes the same time too (almost, 2secs more 9m 24s vs 9min 26s, but i doubt that the 2 secs are enough to reencode and dther), so i would strongly guess that dither only is applied to lossless dts-hd when decoing to wav or flac or that the information on the wiki is misleading,

so my final question is: is it save to use the -dontpatchdts switch to keep the (useless) bit flag as it is?

I would guess yes, but maybe someone here can give me more information, so that i feel more satisfied doing it

Originally Posted by Etroxamin

However on a wiki i read that -dontpatchdts switch applies a dither.
will this switch really apply a dithering to a normal .dts file?

No, and if it's this wiki, it doesn't claim that standard DTS files will be dithered when that switch is used.

Originally Posted by Etroxamin

and is the patching to 24 bit change anything else than a metaflag change somewhere inside the dts file?

No. It's just metadata.

Originally Posted by Etroxamin

as far as i have understand it, lossy audio usually dont have a bit depth at all,

Correct.

Originally Posted by Etroxamin

so my final question is: is it save to use the -dontpatchdts switch to keep the (useless) bit flag as it is?

Yes.

[Etroxamin]

Originally Posted by Richard1485

No, and if it's this wiki, it doesn't claim that standard DTS files will be dithered when that switch is used.

No. It's just metadata.

Correct.

Yes.

Great

thank you very much for your answer.

Btw, no that wasn't the wiki where i have read this, it was here:

https://en.wikibooks.org/wiki/Eac3to/How_to_Use

(this seems to be the same, but with a very slightly different url)

but after rechecking the information there, it actually really just seems to be DTS-HD, but i somehow ignored that and thought this can happen to any DTS track ... wellm thanks again for clarification

[Pochka]

Thank you tebasuna51 and Etroxamin

[tebasuna51]

Originally Posted by Etroxamin

Btw, no that wasn't the wiki where i have read this, it was here:

https://en.wikibooks.org/wiki/Eac3to/How_to_Use

(this seems to be the same, but with a very slightly different url)

Both are out of date concerning to DTS-HD decoder, in the changelog:

v3.30 (2015)
* libDcaDec is now default for all DTS tracks except XSA / low bitrate

libdcadec.dll is included in eac3to package, and can decode bit exact DTS-MA (unique DTS with util metadata 'Source PCM Resolution': 16 or 24).

Some old DTS standard encoders (Surcode) put always Source PCM Resolution to 24 even with PCM 16 bits sources, then that metadata is useless and maybe false.

Now a updated version (suport for DTS Express and other improvments) of libdcadec is included in ffmpeg (not included in 2015 libav dll's in eac3to)

[Sakura-chan]

Originally Posted by tebasuna51

Just add the inverse delay, for instance:


or

I know this is long overdue, but thanks. Yeah, I figured the only way was to add the inverse delay.

Originally Posted by Asmodian

Why would you want to ignore delay? It is a flag telling all players to add/subtract that much audio before playing, so unless it is normally out of sync, what is the use case for ignoring that field? Is it that the flag smaller than Xms of silence and you will reapply it when muxing?

Maybe some other reason I haven't thought of?

Generally the delay it's correct, but I had a couple of discs that had some random delay set that was wrong. If I let eac3to process the delay I ended up with out of sync audio. You just had to ignore the delay, the track was perfectly in sync. Curiously mkvmerge seemed to ignore the delay and the remuxed file was in sync. But I needed eac3to as I use it to convert lpcm to flac from source, without extracting/remuxing first. So far I haven't encountered more discs with wrong delays.



Now, something I really can't figure out and has bothered me for a while.

When processing a bluray playlist eac3to likes to label the chapters as the first track, so chapters is 1, video is 2, first audio track is 3 and so on. When processing any other file type 1 is the video, 2 is audio. Why chapters in playlists are always first I do not know. Most sensible thing I think would be to put them at the end (since the chapters are arguably the least important "track") or to make it more batch friendly have a non-number to them. Like:

1: h264/AVC, 1080p24 /1.001 (16:9)
2: DTS Master Audio, German, 2.0 channels, 24 bits, 48kHz
   (core: DTS, 2.0 channels, 1509kbps, 48kHz)
3: DTS Master Audio, English, 2.0 channels, 16 bits, 48kHz
   (core: DTS, 2.0 channels, 1509kbps, 48kHz)
4: Subtitle (PGS), German
5: Subtitle (PGS), English
C: Chapters, 12 chapters

Anyway, those damn chapters mess up by batches when extracting from a mix of mpls and m2ts sources. I have the list of files and the tracks I need but then I have to manually search the batch offsetting the mpls track numbers and it's a pain in the ass.

Is there a way to leave out chapters from the track list?

I'm trying ffmpeg, it ignores chapters completely, video always falls on 1, audio on 2 and so on, easy to batch. Still, I'm unsure whether ffmpeg supports seamless branching (have yet to try) and has some not-very-nice looking warnings (PES packet size mismatch and packet corrupt on DTS tracks), when eac3to processes the playlist without a hitch.

AFAIK, ffmpeg still lacks support for seamless-branching discs. The quirk with eac3to's track order does present problems on occasion. Unless there's an undocumented switch somewhere that locks onto the first video track (like the -demux switch does), there probably isn't a ready-made solution. Maybe you could write a batch script with a conditional that handles files differently based on extension.

[Asmodian]

Originally Posted by Richard1485

Maybe you could write a batch script with a conditional that handles files differently based on extension.

Parsing EAC3TO cmd output is weird, but it does work. I did one in Python.

[AnimeN]

Hi, anyone could help me? I need to cut .aac file without reencode from time hh:mm:ss to time hh:mm:ss
I don't know how work with edit parameter

Thanks a lot

[tebasuna51]

You have the answer in the FAQ (convert hh:mm:ss to seconds):

besplit -core( -input in.aac -prefix out -type aac ) -split( s1.m1 s2.m2 )

[AnimeN]

Originally Posted by tebasuna51

You have the answer in the FAQ (convert hh:mm:ss to seconds):

besplit -core( -input in.aac -prefix out -type aac ) -split( s1.m1 s2.m2 )

Finally I did with this https://mpesch3.de/

[Hackerjac]

Have been using eac3to for serval years with alot of diff guis, but here yesteday when i wanted to demux some subs i get a strange error, it all happens when loading the disc

Access violation at address 0046CEA9 in module 'eac3to.exe'. Write of address 751C1000.


Log File

[wiggaz]

Originally Posted by Hackerjac

Have been using eac3to for serval years with alot of diff guis, but here yesteday when i wanted to demux some subs i get a strange error, it all happens when loading the disc

Access violation at address 0046CEA9 in module 'eac3to.exe'. Write of address 751C1000.


Log File

Happened to me also.
madshi is working on it.

[Hackerjac]

Originally Posted by wiggaz

Happened to me also.
madshi is working on it.

Thanks for the info and link


Had a feeling it had something to do with latest Windows updates

[Hackerjac]

Originally Posted by wiggaz

Happened to me also.
madshi is working on it.

Acording to the comments in your link the newly Windows Update resolve the problem, gonna try installing that

[tebasuna51]

Just to resume:

Windows Updates KB5006744 and KB5006847 gives me an Access Violation
Windows Updates KB5007206 KB5007884 and eac3to is working again!

[VAMET]

Dear Friends

Please correct me, if I am wrong. I have movie.mkv file with Atmos - Track 2. When I will use command:

eac3to movie.mkv 2: atmos.thd

Will it demux Atmos track to atmos.thd without any changes? If I will mux it again to other .mkv file, will it be exact the same (1:1) Atmos track like in original movie.mkv?

Thank you in advance for your reply.

Sincerely

[tebasuna51]

Originally Posted by VAMET

...
Will it demux Atmos track to atmos.thd without any changes?...

Yes, but to be sure show the eac3to log to see if eac3to found any problem when extract it.

[DanDare1983]

Hi, I have a quick question. I currently use the eac3to gui but just wanted to make sure of something. For DTS-HD MA audio, I use dtshd....is this correct? Also I wanted to see if theirs an option where all DTS-HD MA 1.0/2.0 tracks are made into flac files. I would like to make it easy by just using the demux option but I can't if 1.0/2.0 tracks exist as I like to save space by converting to flac. Also would like to say what a fantastic program eac3to is and many thanks for keeping it active with updates.

[tebasuna51]

Originally Posted by DanDare1983

I currently use the eac3to gui

What GUI?

I use dtshd....is this correct?

Yes, but you can use also .dts without problems.
Many soft use the first bytes in file (the header) to identify the format, not only the extension.

Also I wanted to see if theirs an option where all DTS-HD MA 1.0/2.0 tracks are made into flac files.

Don't exist a specific option, you must recode each track.
Always the recoded flac save space over the DTS-MA, not only 1/2 channels also 5.1 or 7.1.