Need help with an .ac3 stereo track!

[b66pak]

hi


i am trying to decode to .wav an .ac3 stereo track (from a capped hdtv movie) but i get a blank result with last behappy or blank+distorted with last eac3to...


here is a 2 min sample:

http://www.megaupload.com/?d=5HXCF86B

http://www.mediafire.com/?vtgitmejcvd



mediainfo on original file

Audio
ID : 1
Format : AC-3
Format/Info : Audio Coding 3
Codec ID : A_AC3
Duration : 2h 11mn
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Stream size : 360 MiB (8%)
Language : English


mediainfo on demuxed file

General
Complete name : F:\audio.ac3
Format : AC-3
Format/Info : Audio Coding 3
File size : 360 MiB
Duration : 2h 11mn
Overall bit rate : 384 Kbps

Audio
Format : AC-3
Format/Info : Audio Coding 3
Duration : 2h 11mn
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Surround: L R, LFE
Sampling rate : 48.0 KHz
Stream size : 360 MiB (100%)


eac3to on demuxed audio

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

F:\Tools_Audio\eac3to>eac3to f:\audio.ac3
AC3, 2.0 channels, 2:11:07, 384kbps, 48khz, dialnorm: -27dB


leeaudbi on demuxed audio

==========================================================
File ........: F:\audio.ac3
Size ........: 377601024 bytes

----------------------------------------- First Frame Info
SampleRate ..................: 0 (48000 KHz)
BitRate .....................: 14 (384 Kb/s)
Version (bsid) ..............: 6 (Alternate sintax)
Bit Stream mode (bsmod) .....: 0 (main audio service: complete main, CM)
Audio coding mode (acmod) ...: 2 (2/0 - L, R)
Dolby Surround Mode .........: 0 (not indicated)
Low frequency effects channel: 0 (Not present)
Dialogue normalization ......: - 31 dB
RF atenuattion ..............: 8.78 dB Frame: 1
Languaje ....................: 0 (Not present)
Audio Production Info .......: 0 (Not present)
CopyRight bit ...............: 0
Original bit ................: 0
Preferred stereo downmix mode: 0 (not indicated)
Lt/Rt center mix level ......: 0 (1.414, +3.0 dB)
Lt/Rt surround mix level ....: 0 (1.414, +3.0 dB)
Lo/Ro center mix level ......: 0 (1.414, +3.0 dB)
Lo/Ro surround mix level ....: 0 (1.414, +3.0 dB)
Dsurexmod Indication ........: 0 (not indicated)
Dheadphonmod Indication .....: 0 (not indicated)
Type of A/D converter .......: 0 (Standard)
Reserved bits ...............: 1
Additional Bsi ..............: 0 (Not present)
Block switch flags ..........: 0
Dither flags ................: 3
Dynamic Range gain ..........: 8.78 dB Frame: 1
------------------------------------------- Rest of Frames
Frame SR BR PB BS BM AM LF DN DyRaCo Bytes Before Header
--------- -- -- -- -- -- -- -- -- ------ -------------------
* 5 0 14 0 6 0 7 1 31 9.17
--------------------------------------------- Revised Info
RF Ov. Pr. min/max : -13.21 / 9.17 dB
Dyn. Range min/max : -13.21 / 9.17 dB
Total Frames ......: 245834
Duration ..........: 7866.688 seconds. ( 2 h. 11 m. 6.688 s.)
------------------------------------------------- End Info

i am waiting for suggestions...
_

[poisondeathray]

You are trying to convert AC3=>WAV ?

There seems to be an error in that .ac3 sample ; and neither ac3fix or delaycut could fix it

Foobar2000 => failed
NicAC3Source() + Behappy => failed

DirectShowSource() + Behappy => success (using ac3 filter on my system, behappy r50502)

[b66pak]

there is no error in the audio file (tested with last delaycut!)...it plays fine (ffdshow + haali + mpc)...i provided this sample in order to help behappy and eac3to developers to improve their applications...
_

[rik1138]

There does seem to be something 'not right' with the file. I have an AC3 header reading tool that won't even load it... But, there's an old AC3 to WAV converter called PX3 that actually worked fine to make it a WAV file, so you might try that...

http://www.digital-digest.com/software/download.php?sid=12&ssid=0&did=1

Or Google for px3conv_004.zip.

For some reason I've had this program on my computer since I started ripping DVDs, and I go back to it every now and then... Seems to always work with 2.0 AC3, not sure if it even supports 5.1 or not...

[tebasuna51]

there is no error in the audio file (tested with last delaycut!)...
Of course there are a important error:
Time 00:00:00.128; Frame#= 5. Some basic parameters changed between Frame #1 and this frame

...i provided this sample in order to help behappy and eac3to developers to improve their applications...

At least BeHappy work fine with this file and decode the first 4 frames like stereo, the rest of frames are 5.1 and can't be stored in 2.0 format then put silence, is the defined behaviour.

Use Delaycut to Delay -128 ms (this delete the 4 firts stereo frames) and you obtain a correct ac3 file.

[b66pak]

it works...thanks tebasuna51...it will be nice if nicaudio will issue a warning for this kind of files...
_