Trying to isolate LPCM audio

[pooksahib]

Hi. I have a video with AC-3 and PCM audio. I've read that the PCM sounds much better so I want to make an encode using MeGUI with the PCM audio only i.e. encode the video but not the audio. First step is to demux the PCM track, yes? I've tried doing so with mkvtoolnix and tsMuxeR but both resulting audio files are white noise.

If I open the video with Avidemux and select the LPCM track, I get white noise. However, MPC-HC and VLC have no problem playing either track.

Can anyone see what the problem is and maybe suggest how I go about getting a PCM track that I can point MeGUI to? Thank you.

[hello_hello]

If it happens to be similar to an old issue with MakeMKV, eac3to should extract it (MeGUI's HD Streams Extractor). The source file is MKV, I assume? Have you tried extracting with MeGUI's File Indexer?

Or try dragging and dropping the MKV into MeGUI's audio section. Normally MeGUI would check for audio and create a script to encode it, although it only checks for a single audio stream. MeGUI's OneClick encoder should detect multiple audio streams and it'll let you just the ones to encode or copy and it'll also copy the video rather than re-encode it.

Failing all that, post MeGUI's log file after it's failed to open the source, or the MediaInfo for the source, or a tiny sample if you can split it with MKVToolnixGUI.

[pooksahib]

Hello hello_hello. You assume wrongly - the source is VOB (error in OP - the audio tracks are AC-3 and PCM, not AAC). I tried eac3to but regardless of whichever output format I chose, it demuxed everything 'as is' i.e. video, AC3 and a pcm file, the latter being unplayable. Then I tried the MeGUI HD Stream Extractor (I was unaware of that feature, so thanks). It only gives one output format, W64, which I can play with MPC-HC but it remains to be seen if it'll work on my media player in the lounge (I googled W64 and it's for Sony products apparently). I'll give it a go tomorrow and see what happens. Thanks for your help, as ever.

PS. I've just copied the W64 file over to my Dune. It doesn't like it.

PPS. Things are moving on. OneClick Encoder (again, not a feature I've ever used) gave me a video with just the PCM stream so that's great. I'm not sure if the Dune likes PCM but if not I'll simply convert the W64 to FLAC or WAV using XMediaRecode. Thanks again. I've gotta go to bed now...

[netmask56]

If it is a DVD rip ie a full set of VOBs and IFO and BUP files all you need is MakeMKV. When MakeMKV displays the contents, it will show the video and both sound tracks and any subtitles, simply deselect the tracks you don't want and then process. You will then have a MKV file with PCM audio assuming you deselected the AC3 track. No re-encoding quality in = quality out. Possibly MakeMKV will work with just the VOB files but I haven't tried that.

[hello_hello]

Hello hello_hello. You assume wrongly - the source is VOB (error in OP - the audio tracks are AC-3 and PCM, not AAC).

MeGUI's File Indexer shouldn't have any problem extracting it, using the default indexer for vob files... DGIndex.

I tried eac3to but regardless of whichever output format I chose, it demuxed everything 'as is' i.e. video, AC3 and a pcm file, the latter being unplayable. Then I tried the MeGUI HD Stream Extractor (I was unaware of that feature, so thanks). It only gives one output format, W64, which I can play with MPC-HC but it remains to be seen if it'll work on my media player in the lounge (I googled W64 and it's for Sony products apparently). I'll give it a go tomorrow and see what happens. Thanks for your help, as ever.

W64 is an extension to the wave file format, mostly for supporting file sizes greater than 4GB.

Top/left of the HD Streams Extractor window it says "Settings". It's a menu item even though it doesn't look like one, and for some reason most of the extraction options are disabled by default. If you click on Settings and check the "Extract As" menu items, you'll be able to convert with the HD Streams Extractor while extracting.

PPS. Things are moving on. OneClick Encoder (again, not a feature I've ever used) gave me a video with just the PCM stream so that's great. I'm not sure if the Dune likes PCM but if not I'll simply convert the W64 to FLAC or WAV using XMediaRecode. Thanks again. I've gotta go to bed now...

OneClick would've extracted it from the vob file with DGIndex, I'm pretty sure.

[pooksahib]

Thanks guys. I understand OneClick much better now - once Queued and Started, the selected PCM stream is produced as a WAV file. I'm good, thanks again.