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Old 13th July 2010, 18:59   #10321  |  Link
crl2007
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Sometimes, when I join multiple m2ts files and demux the streams, the end result shows 13 hours as duration.

I join multiple m2ts files from branched discs, for backup as a single m2ts. So it should have 2 hours, not 13.
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Old 16th July 2010, 16:39   #10322  |  Link
hubblec4
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hello

can everybody help me with the second pass. i have a trueHD track. i want convert it to flac. when the first pass ready the second pass starts, with the message superfluous bits detected: reduce bitdepth from 24 to 16bit. but the second-pass-file sounds damaged.
But the first-pass-flie sounds good(perfect)

is there an option to disable the second pass?


and how i get a full-list of the option by eac3to?

Last edited by hubblec4; 16th July 2010 at 22:38.
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Old 16th July 2010, 16:46   #10323  |  Link
Inspector.Gadget
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What do you mean "sounds damaged"? What's the difference in sound between the original and the encoded FLAC file? eac3to is pretty good about throwing out only padding in lossless audio tracks.
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Old 16th July 2010, 16:55   #10324  |  Link
Midzuki
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Quote:
Originally Posted by hubblec4 View Post
is there an option to disable the second pass?

and how i get a full-list of the option by eac3to?
http://en.wikibooks.org/wiki/Eac3to/How_to_Use

but I'm not sure if dropping the 2nd pass will be a solution
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Old 16th July 2010, 16:57   #10325  |  Link
hubblec4
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you cant understand speech in this file. the musik is distorted. icant explain that exactly, but you hear nothing right.

the bit depth reducing from 24 to 16 bit is not necessary. you know the option to disable the second pass?

i can manually abort the cmd after finished the first pass and then i have the firstpass-file.

Last edited by hubblec4; 16th July 2010 at 22:37.
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Old 16th July 2010, 16:57   #10326  |  Link
hubblec4
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Quote:
Originally Posted by Midzuki View Post
http://en.wikibooks.org/wiki/Eac3to/How_to_Use

but I'm not sure if dropping the 2nd pass will be a solution
ok. i've found it. thanks.

i think is a good solution, because the firstpass-audio sounds perfect with a bit depth of 24.
and the secondpass-file with 16bit sounds very bad.

Last edited by hubblec4; 16th July 2010 at 22:36.
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Old 16th July 2010, 17:11   #10327  |  Link
deathlord
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Quote:
Originally Posted by hubblec4 View Post
ok. i've found it. thanks.

i think is a good solution, because the firstpass-audio sounds perfect with a bitdeth of 24.
and the secondpass-file with 16bit sounds very bad.
The only reason eac3to uses only 16 bits and not 24 in this track is that only those bits contain audio information. The 8 least significant bits are empty. Eac3to does not need to do a second pass in order to strip these. So the second pass must have another reason, e.g. because eac3to detects clipping.
I suspect there is something (slightly) wrong with the file and that's why the second pass produces garbage (this happend to me once).
In any event, if the result of the first pass is ok, i.e. audio is in sync throughout the movie, you can use that of course.
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Old 16th July 2010, 18:44   #10328  |  Link
hubblec4
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here the log with second-pass

eac3to v3.21
command line: eac3to.exe "00000 - 6 - TrueHD+AC3, German, 5.1 channels, 48kHz DELAY 125ms.thd+ac3" "deu.flac" -50mb
------------------------------------------------------------------------------
TrueHD/AC3, 5.1 channels, 48kHz
(embedded: AC3, 5.1 channels, 640kbps, 48kHz)
Extracting TrueHD stream...
Decoding with libav/ffmpeg...
Encoding FLAC with libFlac...
Creating file "deu.flac"...
The original audio track has a constant bit depth of 16 bits.
Superfluous zero bytes detected, will be stripped in 2nd pass.
Starting 2nd pass...
Decoding FLAC...
Reducing depth from 24 to 16 bits...
Encoding FLAC with libFlac...
Creating file "deu.flac"...
The processed audio track has a constant bit depth of 16 bits.
eac3to processing took 25 seconds.
Done.
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Old 16th July 2010, 20:48   #10329  |  Link
Snowknight26
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Quote:
Originally Posted by hubblec4 View Post
eac3to v3.21
Enough said.
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Old 16th July 2010, 20:54   #10330  |  Link
Atak_Snajpera
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@madshi
can you add option to automatically ignore .m2ts in playlist if number of audio channels is not constant. In this example also frame rate is different in first file.

Movie Downfall
Code:
eac3to v3.22
------------------------------------------------------------------------------
1) 00014.mpls, 00034.m2ts+00014.m2ts, 2:35:21
   - Chapters, 35 chapters
   - VC-1, 1080p24 /1.001 (16:9)
   - AC3, German, stereo, 48kHz

00034.m2ts
M2TS, 1 video track, 1 audio track, 0:00:37, 29.766p
1: Chapters, 35 chapters
2: VC-1, 1080p24 /1.001 (16:9)
3: AC3, German, 2.0 channels, 192kbps, 48kHz, dialnorm: -27dB

00014.m2ts
M2TS, 1 video track, 1 audio track, 0:00:29, 24p /1.001
1: VC-1, 1080p24 /1.001 (16:9)
2: AC3, German, 5.1 channels, 640kbps, 48kHz, dialnorm: -27dB
Sample
http://www.mediafire.com/file/zyyedj..._CLIPPED.zip_0
http://www.mediafire.com/file/hujn1t..._CLIPPED.zip_1
http://www.mediafire.com/file/n1zmqn..._CLIPPED.zip_2

you will have to combine them before extracting:
Code:
copy DOWNFALL_CLIPPED.zip_0 /b + DOWNFALL_CLIPPED.zip_1 /b + DOWNFALL_CLIPPED.zip_2 /b DOWNFALL_CLIPPED.zip /b

Last edited by Atak_Snajpera; 16th July 2010 at 21:07.
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Old 16th July 2010, 21:57   #10331  |  Link
hubblec4
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Quote:
Originally Posted by Snowknight26 View Post
Enough said.
ok you have right. with eac3to3.22 it works. eac3to make the second-pass and reduce the bitdepth to 16bit. but the file size is the same like 24bit. before the 24bit file was 1,4gb and the 16bit-file 0,9gb.


why two passes? the truehd+ac3-source is 16bit and eac3to convert it to 24bit first and then to 16bit??

so i can use the switch -down16 then start eac3to one pass only.

Last edited by hubblec4; 16th July 2010 at 22:45.
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Old 17th July 2010, 10:34   #10332  |  Link
yesgrey
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Quote:
Originally Posted by hubblec4 View Post
why two passes? the truehd+ac3-source is 16bit and eac3to convert it to 24bit first and then to 16bit??
It starts converting to 24bit because it's the indicated bit depth. After processing the entire file eac3to realizes that the effective bit depth is 16 bit, hence the bit depth reduction.

If you start using always the -down16, the files which would be effectively 24 bit will be reduced to 16 bit, and you might not want that.
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Old 17th July 2010, 16:13   #10333  |  Link
hubblec4
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Quote:
Originally Posted by yesgrey View Post

If you start using always the -down16, the files which would be effectively 24 bit will be reduced to 16 bit, and you might not want that.
no, thats for this conversion only.

other 16bit sources will directly encoded with 16bit.
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Old 17th July 2010, 18:54   #10334  |  Link
deathlord
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Quote:
Originally Posted by hubblec4 View Post
no, thats for this conversion only.

other 16bit sources will directly encoded with 16bit.
TrueHD is always 24 bit, but sometimes it only contains 16 bit of audio data, which can only be seen after reading the whole track. Some time ago, eac3to wrote two tracks, a 16 and a 24 bit one. Apparently, now eac3to starts a second pass to write a 16 bit track in case it was only 16 effectively. So if you always use -down16 on thd tracks, you will lose the least significant 8 bit of audio data in case of a "real" 24 bit track.
However, if this is an audible loss of audio quality is highly questionable. I only use 16 bit for all formats.
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Old 17th July 2010, 19:21   #10335  |  Link
ron spencer
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Just a quick question google has not helped with.

I would like to downmix dts to 2.0, which is easy. But I cannot seem to find what flac compression options eac3to uses? Can I choose 8? Or does it do that by default?

thanks!!!
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Old 17th July 2010, 20:15   #10336  |  Link
deathlord
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eac3to uses level 8:
http://forum.doom9.org/showthread.ph...el#post1222771
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Old 18th July 2010, 15:06   #10337  |  Link
hubblec4
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Quote:
Originally Posted by deathlord View Post
TrueHD is always 24 bit, but sometimes it only contains 16 bit of audio data, which can only be seen after reading the whole track. Some time ago, eac3to wrote two tracks, a 16 and a 24 bit one. Apparently, now eac3to starts a second pass to write a 16 bit track in case it was only 16 effectively. So if you always use -down16 on thd tracks, you will lose the least significant 8 bit of audio data in case of a "real" 24 bit track.
However, if this is an audible loss of audio quality is highly questionable. I only use 16 bit for all formats.
ok i understand this stuff now.
i dont use the switch -down16 for other convertions. only in this case.
with the v3.22 create eac3to a 24bit firstpass file and then the secondpass file with 16bit, which works fine. the original truhd.file is defintiv 16bit.
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Old 20th July 2010, 18:57   #10338  |  Link
mastrandrea
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Hi, is there a way to stretching an audio file to a given time?
In my case I would like to stretch a track by adding 400ms to it, is it possible with eac3to?

(Thanks for this really useful tool!)
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Old 20th July 2010, 23:06   #10339  |  Link
hubblec4
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Quote:
Originally Posted by mastrandrea View Post
Hi, is there a way to stretching an audio file to a given time?
In my case I would like to stretch a track by adding 400ms to it, is it possible with eac3to?

(Thanks for this really useful tool!)
stretch by 400ms?? i think you mean a delay of 400ms.

you can use this switch +400ms
(eac3to input.xxx output.xxx +/-400ms
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Old 21st July 2010, 00:21   #10340  |  Link
mastrandrea
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No, I was meaning I need to sync audio and video, and the audio is 400ms shorter.
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