Problem extracting 5.1ch ac3 audio to Stereo

[vulcan4d]

I have a xvid video with 5.1ch ac3 audio encoded. I am converting the video but the audio keeps messing up while converting to stereo. Some of the sound like voices are very faint when compared to the origonal audio stream. I have tried every tool to extract the audio from the video and have it converted to wav, mp3, whatever and it just keeps messing up. Any tools you guys recommend that might do the trick?

[mats.hogberg]

Demux audio track (direct stream) with VirtualDubMod.
Decode/downmix with HeadAC3he.

/Mats

[sanjayk]

Open the file in VirtualDubMod. Go to Streams > Streams List. Select the audio stream. Click Demux buttom. You will get your AC3 file.

Load in file in HeadAC3he and convert to wav or MP2 or MP3.

[vulcan4d]

Thank you guys, worked like a charm.

[liorde]

Hi,

Is there a way to extract the sound track DIRECTLY from VDubMod to WAV or MP3 2channels? I tried once to do so but i got an error message that "No Audio Decompressor was found". What audio decompressor do I need for this anyway?


Thank-you.

[mats.hogberg]

You need this.

/Mats

[DRP]

Another alternative method if I may so humbly suggest is to open the AVI in GoldWave to get the WAV. Perform replygain on WAV using WaveGain to increase volume and then convert back to MP2 (for VCD conversion) using tooLame or AC3 (for DVD conversion) using TMPGEnc AC-3 Sound Plug-in via DVD-lab PRO.

[mats.hogberg]

Well, if the goal is to create a DVD, you're better off just demuxing the AC3 stream, and use that when authoring the DVD. Decoding to wav, then reencoding to AC3 again won't do you no good.

/Mats

[DRP]

Unless of course the problem is just that the volume is too soft which is the case with many retail DVDs

[mats.hogberg]

Strange - never had any problem with the AC3 track from any commercial DVD.

/Mats

[guns1inger]

Too many kiddies trying to watch DVDs in their bedroom when they should be asleep. Need to keep the volume down 'cause the bangs are loud, but the voices are sooooo soft

There is nothing wrong with AC3 mixing that a decent home theatre won't fix. In the mean time, turn up the TV or go to bed when mummy tells you.

[DRP]

Try the R1 release of the 2003 release of The Italian Job DVD. The AC3 audio is so soft that by the time you've turned the amp volume up high enough to hear anything you need to load half a set of encyclopaedias on the speakers to keep them from walking across the floor with the amplifier hum.

The waveform of the AC3 is almost completely flat. It needs 22dB pumped into it to make it "normal" loudness.

[mikiem]

A BIG FWIW...

Often the theater track is used for the DVD (you'll find ref's to this all over the web)... The theater track makes use of the theater's speaker system, with quiet dialog & *loud* booms. Most DVD players I think, soft & hardware, have settings to apply audio compression, playing everything at a volume level closer to a happy medium, though when you're going out spdif those controls don't work.

Sooo,,, software like DGIndex have a convert to wav option that includes level adjustment, or decoding to stereo thru graphedit use the cyberlink version, or a host of other means (usually more involved) to adjust the level of the wavs & re-encode, or just re-encode with more modest settings for the ac3. It might be possible to work with the original ac3, changing level settings, but I'm not sure -- never tried or looked into it.

It is handy to modify levels if you live in an apt., are 1/2 deaf like me, or use headphones and don't want to be.