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Old 29th May 2009, 23:30   #8921  |  Link
TinTime
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The AC3 decoder (the Nero one anyway) decodes to 24 bits. It's not the AC3 itself that's 24 bit. If encoding to AC3 just pass it the best quality audio possible - 24 bit in this case. There's no need to reduce to 16 bit.
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Old 30th May 2009, 01:34   #8922  |  Link
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If you use eac3to to recode ac3 640Kbs to 448Kbs the decoder (at least libav) suply audio samples with 32 bits float, and the Aften encoder (libaften) read these 32 bit float to obtain the ac3 stream.
The ac3 stream don't have a fix bitdepth, the quality is measured in bitrate instead.
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Old 30th May 2009, 14:29   #8923  |  Link
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I had some recent difficulty re-authoring a disc with a TrueHD track and the only thing I can pin it on is EAC3to. I will explain more so you can let me know if this is normal behavior for this application.

I demuxed a Dolby TrueHD (TrueHD+AC3) track with EAC3to and then re-encoded the video, after that remuxed back together with tsMuxeR.

My Pioneer SC-LX81 AVR made some spluttering noises and the audio was quite garbled (bitstreamed from LG BD370). My PS3 seemed to decode the audio and send the AVR the LPCM track with no problem.

So I decided to take the disc to work and on 4 other AVR's in the store, the info display showed "DIAL NORM -27" (I think that was the number, I could be off a little but I am sure it was in it's twenties). The AVR's at work seemed to be able to play the audio ok. However, I have never seen such a large number show up on my AVR. It is usually somewhere between +8 and -8 (from memory???). After doing some reading it appears that -27 could be the default dialog normalization figure before any metadata changes are made. This suggested to me that maybe EAC3to removed the dialog normalization when demuxing. To further solidify my thoughts, I remuxed the same tracks, only this time avoiding using the demuxed (thd+ac3) track from EAC3to, instead I loaded the original m2ts file into tsMuxeR and selected the TrueHD track that way.

This time it played without any problems at all, except now no DIAL NORM notification comes up on my AVR. To sum this post up...

Does EAC3to remove or alter dialog normalization when demuxing? I am aware how this could affect encoding but surely it shouldn't be removed or altered when demuxing, should it?

Last edited by Ryu77; 30th May 2009 at 14:36.
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Old 30th May 2009, 15:09   #8924  |  Link
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Quote:
Originally Posted by Ryu77 View Post
Does EAC3to remove or alter dialog normalization when demuxing?
Yes, change any value of Dialog Normalization to -31 dB
Quote:
I am aware how this could affect encoding but surely it shouldn't be removed or altered when demuxing, should it?
The change only affect this field value in headers (and CRC), is a lossless change without reencode.
This change can't be the source of your problems.
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Old 30th May 2009, 16:11   #8925  |  Link
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If you want to keep the existing dialnorm value then you can use the -keepDialnorm option with eac3to.

A value of -27 is very usual.

As to whether the original value should be kept or not when demuxing, opinion is divided. It's really personal preference. I keep it myself.
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Old 30th May 2009, 23:07   #8926  |  Link
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Quote:
Originally Posted by tebasuna51 View Post
Yes, change any value of Dialog Normalization to -31 dB

The change only affect this field value in headers (and CRC), is a lossless change without reencode.
This change can't be the source of your problems.
Well it obviously was the source of my problem as my receiver didn't like the audio track with the dialog normalization removed. Once remuxed with the dial norm untouched my AVR played it without any issue.


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Originally Posted by TinTime
If you want to keep the existing dialnorm value then you can use the -keepDialnorm option with eac3to.
Thank you, I forgot about that command. I always thought this wasn't a problem with demuxing though. I always thought this was only removed for re-encoding purposes. Now I know different.
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Old 31st May 2009, 00:18   #8927  |  Link
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Well it obviously was the source of my problem as my receiver didn't like the audio track with the dialog normalization removed. Once remuxed with the dial norm untouched my AVR played it without any issue.
Nope, can't be the problem.
The DialNorm isn't removed, is changed to a valid value (-31).

When the receiver read a -27 dB value in DialNorm make a global attenuation of 4 dB.

When the receiver read a -31 dB value in DialNorm make a global attenuation of 0 dB.

Maybe is other problem related to the demux-remux.
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Old 31st May 2009, 01:13   #8928  |  Link
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Quote:
Originally Posted by tebasuna51 View Post
Nope, can't be the problem.
The DialNorm isn't removed, is changed to a valid value (-31).

When the receiver read a -27 dB value in DialNorm make a global attenuation of 4 dB.

When the receiver read a -31 dB value in DialNorm make a global attenuation of 0 dB.

Maybe is other problem related to the demux-remux.
Thank you for your help but as mentioned earlier when I muxed with tsMuxeR only (avoiding EAC3to), the disc created played with no problem at all. So that leaves the only different viarable as EAC3to.

Another oddity I noticed is that when I extracted the AC3 stream from the TrueHD+AC3 track with tsMuxeR, which was originally demuxed with EAC3to, the dial norm registered as +4 on my AVR. Why this reverted back with the core stream, I have no idea. Maybe tsMuxeR altered the metadata back to it's original state somehow.

If you still want the log file, I can post that when I get home from work later today. I thought that the problem was pretty clear cut (and solved) but I can certainly post it later. I posted this as I had originally forgotten about the "-KeepDialnorm command" that TinTime reminded me of. Now that I know that it exists, I will use it to keep the audio as the studio intended.

Last edited by Ryu77; 31st May 2009 at 01:21.
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Old 31st May 2009, 12:46   #8929  |  Link
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Quote:
Originally Posted by Ryu77 View Post
Does EAC3to remove or alter dialog normalization when demuxing? I am aware how this could affect encoding but surely it shouldn't be removed or altered when demuxing, should it?
eac3to removes dialnorm by setting it to -31dB, which is the right way of doing it but the Pioneer receivers are known not to deal with -31dB properly for some reason. Use the -keepdialnorm tag in relation to every Dolby (DD/TrueHD) track you want to demux and you should be fine.
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Old 31st May 2009, 14:58   #8930  |  Link
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Quote:
Originally Posted by peterjcat View Post
eac3to removes dialnorm by setting it to -31dB, which is the right way of doing it but the Pioneer receivers are known not to deal with -31dB properly for some reason.
Nope, the problem in Pionner receiver was when the value is set to 0 dB, but this was corrected at:
v2.85
...
* AC3 and E-AC3 dialnorm removal now uses "-31db" instead of "-0db"

The -31dB must work fine on all players/recievers.
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Old 31st May 2009, 17:38   #8931  |  Link
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Quote:
Originally Posted by tebasuna51 View Post
The -31dB must work fine on all players/recievers.
Yep. My Yamaha amp works with -31dB but not 0. Or rather, it works with 0dB Dialnorm but is really quiet, as you would expect.

Quote:
Originally Posted by peterjcat View Post
eac3to removes dialnorm by setting it to -31dB, which is the right way of doing it but the Pioneer receivers are known not to deal with -31dB properly for some reason. Use the -keepdialnorm tag in relation to every Dolby (DD/TrueHD) track you want to demux and you should be fine.
Pioneer amps must be able to handle a value of -31dB surely? This is a valid value. What if the source already has a value set of -31dB? Then the -keepdialnorm switch won't make any difference.
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Old 31st May 2009, 18:24   #8932  |  Link
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Sonic DTS 4.3 or 4.2 ??

I have both the Sonic 4.2 and 4.3 versions and have been using 4.3 since it came out.

I have read somewhere (don't remember where, but on a forum) yesterday that a number of people have had problems with ver 4.3 decoding DTS to AC-3 and that 4.2 was more stable and the one to use.

Can anyone comment on this and confirm if it's true or not?
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Old 31st May 2009, 23:00   #8933  |  Link
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Quote:
Originally Posted by tebasuna51 View Post
Nope, the problem in Pionner receiver was when the value is set to 0 dB, but this was corrected at:
v2.85
...
* AC3 and E-AC3 dialnorm removal now uses "-31db" instead of "-0db"

The -31dB must work fine on all players/recievers.
What about TrueHD? As mentioned earlier it was only the TrueHD track that caused the problem. When I extracted the AC3 core with tsMuxeR from the same problematic track the core somehow reverted back to dial norm +4. Also, my Pioneer AVR didn't display a dial norm fugure, it was one of the AVR's at work that showed something like -27 but the wierd part was they seemed to manage to play the audio.

I don't know what caused the problem but all I know is when I used tsMuxeR exclusively to handle the demuxing that everything was ok.

Last edited by Ryu77; 31st May 2009 at 23:02.
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Old 31st May 2009, 23:05   #8934  |  Link
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Why does eac3to remove the fullrange flag from h264 streams?
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Old 1st June 2009, 00:05   #8935  |  Link
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Because there are almost always wrong, mostly due to a bug in the old Tandberg h.264 encoder that most European tv stations use.
 
Old 2nd June 2009, 00:29   #8936  |  Link
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Just to follow up on my previous posts...

I tested the disc created with the audio track (Dolby TrueHD) demuxed with EAC3to and then remuxed with tsMuxeR (after re-encoding video) on an Onkyo TXNR906 at work (again) and the display showed DIAL NORM -27dB. This same disc is the one that was spluttered and garbled on my Pioneer SC-LX81 (SC-07 in the USA). Strangely enough the disc displaying -27 seemed a little louder at the same volume setting on the Onkyo AVR.

However, the disc created with the audio track demuxed/remuxed exclusively with tsMuxeR didn't display anything at all on the Onkyo AVR but displays DIAL NORM +4 on my Pioneer AVR (and plays perfectly on both).

Another point is, it was said earlier that EAC3to doesn't remove dialog normalization but instead changes it to -31. If that is the case, why does the Onkyo AVR display -27? Also, why does the Dolby Digital core extracted from the same TrueHD track revert back to +4?

Also, another interesting note. I tested Transformers with a regular Dolby Digital track and it displayed DIAL NORM +4 on both the Onkyo TXNR906 at work and my SC-LX81 at home... ??? So that would indicate that they both indeed use the same measurement system. Maybe my Pioneer AVR didn't like the DIAL NORM -27 metadata setting. It also seems that EAC3to may have handled this TrueHD track different to usual.

Last edited by Ryu77; 2nd June 2009 at 00:53.
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Old 2nd June 2009, 01:31   #8937  |  Link
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Ryu77,

I've had issues with Dolby TrueHD and my Pioneer receiver for a long time. (See this thread). I'm virtually certain the issue is some kind of metadata in the TrueHD stream that's being altered by eac3to, tsMuxer, or one of the other common tools that happens to cause the audio on the Pioneers to not play back properly.

I'm going to try again with the latest tsMuxer, and use the -keepdialnorm option on eac3to and see if it fixes the problem.

Gotto go dig out the Iron Man BD for the 57th time ...
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Old 2nd June 2009, 02:17   #8938  |  Link
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Quote:
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Ryu77,

I've had issues with Dolby TrueHD and my Pioneer receiver for a long time. (See this thread). I'm virtually certain the issue is some kind of metadata in the TrueHD stream that's being altered by eac3to, tsMuxer, or one of the other common tools that happens to cause the audio on the Pioneers to not play back properly.

I'm going to try again with the latest tsMuxer, and use the -keepdialnorm option on eac3to and see if it fixes the problem.

Gotto go dig out the Iron Man BD for the 57th time ...
Hello Joe,

I did state above that when using tsMuxeR exclusively (avoiding EAC3to) to demux/remux that the TrueHD track plays without any problem on my Pioneer SC-LX81 (SC-07). I have authored a few discs with TrueHD and DTS-HD MA and they all play fine. Previously I used tsMuxeR to do the demuxing. It was only recently that I started using EAC3to to handle the demuxing and that is when the TrueHD problem occured.

I do like the ease of use that EAC3to offers when locating the main movie playlist and also I believe it handles seamless branching better. However, I am not sure what it is doing to the dialog normalization to make my Pioneer AVR to reject the track. So for the time being I may need to stick with tsMuxeR for all the work.
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Old 2nd June 2009, 16:14   #8939  |  Link
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Hi,

I have a DTS-ES 6.1 24bits track, and I would like to convert it, to a 2CH AC3 192.
Is this the correct command line for it, or am I missing something?

eac3to c:\a\a.dts c:\a\a.ac3 -down2 -normalize -192

Do I have to worry about that 24bit, and use -down16 too?

Thanks.
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Old 3rd June 2009, 13:54   #8940  |  Link
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Quote:
Originally Posted by SomeJoe View Post
Ryu77,

I've had issues with Dolby TrueHD and my Pioneer receiver for a long time. (See this thread). I'm virtually certain the issue is some kind of metadata in the TrueHD stream that's being altered by eac3to, tsMuxer, or one of the other common tools that happens to cause the audio on the Pioneers to not play back properly.

I'm going to try again with the latest tsMuxer, and use the -keepdialnorm option on eac3to and see if it fixes the problem.

Gotto go dig out the Iron Man BD for the 57th time ...

Does this happen on every movie with TrueHD or is from movie to movie with TrueHD i ask because im having what seems to be the same problem, theres movies that are messed up and others that are not and im using a Pioneer receiver aswell. If the audio has problems do you hear it right away meaning through out the movie or is it parts of the audio during the movie?

I take it you have no problems with DTS-HD Master or PCM audio when demuxed and then remuxed?

Last edited by DoomBot; 5th June 2009 at 01:40.
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