AC3 to WAV conversion failing

[mikebo]

Hi everyone -
I demuxed 2 channel PCM audio from a concert DVD using DVD Decrypter. I used dBpoweramp to convert all the resulting AC3 files to WAV. All of them worked except one file - the converter errors out and the resulting WAV file is 1KB of garbage.

I thought the AC3 file might be corrupt, but it's not. I downloaded the demo version of "AC3 Decoder" from mediatwins.com, and this program has no trouble converting this file AC3 to WAV. It sounds great!

So, is this a known problem with dBpoweramp, AC3filter, or some other codec? Can anyone offer any suggestions on how to do this job with dBpoweramp? I really don't want to have to pay for "AC3 Decoder" unless I have no other choice.

Thanks for any input...
Regards,
mikebo

[LtData]

Re: AC3 to WAV conversion failing

The file it failed on, you are sure it was a 2-channel AC3 file?

[mikebo]

Re: AC3 to WAV conversion failing

According to DVD DeCrypter, the 2-channel stream ID is 0x80, and the 6-channel stream ID is 0x81. I'm only de-muxing stream ID 0x80. Only chapter 11 of 15 is giving me a problem. dBpoweramp converts chapters 1-10 and 12-15 AC3 files to WAV with no problem. Here's the stream info:

0x80 - Audio - AC3 / 2ch / 48kHz / DRC / English / LBA: 358412 / PTS: 00:15:36.265 / Delay: -169ms
0x81 - Audio - AC3 / 6ch / 48kHz / DRC / English / LBA: 358411 / PTS: 00:15:36.201 / Delay: -233ms
0xE0 - Video - MPEG-2 / 720x480 (NTSC) / 16:9 / Letterboxed / LBA: 358410 / PTS: 00:15:36.435 / Delay: 0ms

I ripped the chapter 11 multiplex VOB and I'm examining the stream with VOBedit, looking at individual packet headers. It's extremely tedious and I'm not sure what I'm looking for... But is it possible that incorrectly formatted frames were purposely inserted in the 0x80 stream as a rudimentary form of copy protection? If so, AC3Decoder ignores them, or converts them properly.

Is there a way to get dBpoweramp to work, possibly by tweaking the settings on AC3filter to ignore errors?

Any suggestions are welcome!
Thanks!
mikebo

PS> I just ripped another concert DVD and got the same problem on only track 7 of 17. Both problems occur 37 and 41 minutes into the shows... strange. I wonder if this is a layer transition problem...

[mikebo]

Re: AC3 to WAV conversion failing

Oh well... Sometimes you get what you pay for...

I'll spend the $20 on MediaTwins AC3 Decoder which just works and quit fiddling around with dBpoweramp and AC3filter - they couldn't get the job done.
mikebo

[dmdevotee]

Re: AC3 to WAV conversion failing

I have installed the dbpoweramp directshow filter and the ac3 filter, but when i want to convert ac3 files to wav dbpoweramp says: "no audio files selected for conversion". What is the problem? thanks

[Spoon]

Re: AC3 to WAV conversion failing

Click the list / rename button in music converter, does that show the correct files?

[LtData]

Re: AC3 to WAV conversion failing

In dBpoweramp Configuration (See "Need to find your version?" below), does it show .ac3 by the DirectShow codec?

[dmdevotee]

Re: AC3 to WAV conversion failing

Click the list / rename button in music converter, does that show the correct files?

do you mean this?

In dBpoweramp Configuration (See "Need to find your version?" below), does it show .ac3 by the DirectShow codec?

No, it doesn't..

[LtData]

Re: AC3 to WAV conversion failing

Per the DirectShow Codec help file:

Got to your Start Menu and click run, then type: "%appdata%\dbpoweramp"
Open up directshow.txt and make sure .ac3 is in there. If it isn't there, add it.

[dmdevotee]

Re: AC3 to WAV conversion failing

Per the DirectShow Codec help file:

Got to your Start Menu and click run, then type: "%appdata%\dbpoweramp"
Open up directshow.txt and make sure .ac3 is in there. If it isn't there, add it.

thanks, it worked