VideoHelp Forum

Our website is made possible by displaying online advertisements to our visitors. Consider supporting us by disable your adblocker or Try ConvertXtoDVD and convert all your movies to DVD. Free trial ! :)
+ Reply to Thread
Results 1 to 2 of 2
Thread
  1. Member
    Join Date
    Jun 2018
    Location
    Americas
    Search Comp PM
    So, I have these DVDs from a boxset that all have a 2.0 DTS track. Except one that shows up as 5.1. When inspecting the VOB file it looks like a proper stereo track, but MakeMKV, eac3to, mkvtoolnix, all produce a "fake" 5.1 track with a strange tag when seen with MediaInfo ("Channel(s)_Original") that suggests it's actually stereo. When opening said track with Audacity the first two channels have sound, the rest are empty. See the mediainfos below:

    Original VOB from DVD
    Code:
    Audio #2
    ID                                       : 189 (0xBD)-137 (0x89)
    Format                                   : DTS
    Format/Info                              : Digital Theater Systems
    Muxing mode                              : DVD-Video
    Duration                                 : 17 min 16 s
    Bit rate mode                            : Constant
    Bit rate                                 : 755 kb/s
    Channel(s)                               : 2 channels
    Channel layout                           : L R
    Sampling rate                            : 48.0 kHz
    Frame rate                               : 93.750 FPS (512 SPF)
    Bit depth                                : 16 bits
    Compression mode                         : Lossy
    Stream size                              : 93.2 MiB (9%)
    DTS extracted from the MakeMKV remux
    Code:
    Audio #2
    ID                                       : 3
    ID in the original source medium         : 189 (0xBD)137 (0x89)
    Format                                   : DTS
    Format/Info                              : Digital Theater Systems
    Codec ID                                 : A_DTS
    Duration                                 : 1 h 12 min
    Bit rate mode                            : Constant
    Bit rate                                 : 755 kb/s
    Channel(s)                               : 6 channels
    Channel(s)_Original                      : 2 channels
    Channel layout                           : L R
    Sampling rate                            : 48.0 kHz
    Frame rate                               : 93.750 FPS (512 SPF)
    Bit depth                                : 16 bits
    Compression mode                         : Lossy
    Stream size                              : 391 MiB (9%)
    Title                                    : Surround 5.1
    Language                                 : Japanese
    Default                                  : No
    Forced                                   : No
    Original source medium                   : DVD-Video
    It's impossible to use "-downStereo" with eac3to, I get this:
    Code:
    a03 Extracting audio track number 3...
    a03 Decoding with libDcaDec DTS Decoder...
    a03 Encoding FLAC with libFlac...
    a03 libDcaDec output changed from 6 channels, 48kHz to 2 channels, 48kHz.
    a03 Creating file "C:\lol.flac"...
    Aborted at file position 262144.
    So far I can extract the "5.1" DTS as is, open it with Audacity, delete the empty channels and export that as FLAC. Ironically the 755 kbps DTS file goes down to a 415 kbps FLAC. Lol, it's an old movie with shit sound, there must be so little data that the fixed bitrate DTS is a waste. In fact, both channels in Audacity looked the same, it must be a mono track originally.

    Aside that, what can you do in these cases of "fake" DTS tracks? How can you get rid of the empty channels?
    Quote Quote  
  2. Old movies are stereo at best - most cases audio was considered unimportant (used to create mood or as dialogue with some "fill gap" music).
    Of course you can convert DTS to 2.0 channel. Alternatively you could in theory create if not multichannel audio then at least artificially created room characteristic multichannel (see no point when you can do this in real life using AV amplifier embedded DSP).
    Quote Quote  



Similar Threads