Buzz in ripped LPCM track

Discussion in 'AnyDVD HD (Blu-ray issues)' started by negativeZero, Mar 2, 2008.

  1. negativeZero

    negativeZero Member

    I'm having an issue ripping my Pat Metheny "The Way Up" concert HD-DVD. The disc contains an LPCM 2.0 channel 16-bit/48kHz audio track that I'd eventually like to demux, but it seems that after I rip it using AnyDVD HD (with eval. license) it has a digital "buzz" sound that is present throughout. When I demux out the LPCM track using EVOdemux and look at the resulting raw LPCM file in a hex editor, I see the pattern 0x1001 (i.e., 0x0110 in LSBF) appear at just about every 0x7da bytes, though this interval is not fixed throughout the file. Anyone have an idea what this could be?

    The disc plays fine from my XBOX 360 drive using PDVD; it is not AACS protected.

    Thanks!
    nZ
     

    Attached Files:

  2. Adbear

    Adbear Well-Known Member

    If it has no AACS then why have AnydvdHD running when you rip it? Try ripping it without Anydvd HD running and see if you get the same problem
     
  3. negativeZero

    negativeZero Member

    That's an excellent question - I suppose so I wouldn't have had to install the UDF driver for XP. But I've now done so and tried to EVOdemux the LPCM track right off the disc file itself with AnyDVD shut down; the 0x1001 pattern is still there. Guess that absolves AnyDVD!

    If anyone happens to have a suggestion re: this problem, your input is appreciated.

    Thanks!
    nZ
     
  4. Adbear

    Adbear Well-Known Member

    If you play the HDDVD from the hard drive does it have the buzz, or is it only there after you demux it?
     
  5. negativeZero

    negativeZero Member

    Adbear,

    Once the .EVO containing the audio track I want is on the HD - either by ripping or now by copying via Windows Explorer - I use mplayer to play it (not aware of any other media players that will play an EVO off an HD). When I do so, I still hear the buzz in the LPCM track. After demuxing via EVOdemux and playing the raw LPCM in GWave, the same buzz can be heard, so I don't think the problem is isolated to EVOdemux. I would suspect that that these two programs (i.e., mplayer and EVOdemux) are demuxing in the same way and leaving container metadata in the LPCM stream. Wish I know more about the E-VOB format; what are the chances the DVD Forum will open the standard now that HD-DVD is no more? :)

    Thanks!
    nZ
     
  6. YaniD

    YaniD Well-Known Member

    Is this "watermarking" perhaps?

    If so, then it doesn't sound as though it is a transparent protection to the user.
     
  7. negativeZero

    negativeZero Member

    I don't imagine this particular issue is caused by watermarking; the buzz is extremely prominent and makes the track unlistenable by anyone. I had considered that it might be due to some type content protection system, but I tend to discount that. I believe it is much more likely due to a software error in the free tools I'm using to manipulate the track arising from the fact that the tools were written based on a reverse engineering of the EVO format rather than official spec's. Certainly an LPCM track needs no decoding, but all the other bits in the container need to be stripped away; my guess is that some of them are being left in.

    Thanks!
    nZ
     
  8. Adbear

    Adbear Well-Known Member

    But have you tried playing it as an HD DVD disc from the harddrive in PowerDVD rather than just the file on it's own? It could be to do with the decoder you system is picking up on for the audio when playing it as a single file
     
  9. seeya

    seeya Active Member

    Use eac3to instead of EvoDemux. That should solve the buzzing problem (EvoDemux has a bug with demuxing EVO LPCM tracks!). Furthermore by using you'll even be able to convert directly to FLAC or WAV.
     
  10. negativeZero

    negativeZero Member

    seeya,

    You're 100% correct; ea3to worked like a charm and now I have a nice 48kHz track to play on my Squeezebox. Sounds great! Thanks for your help!

    nZ