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  1. Member
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    Hello. Maybe you can help. With the tools I have I can only mux 2 audio files to a VIDEO_TS format with an encoding to 224kbps step by ffmpegx. I would prefer to keep the audio files PCM. Is that possible to mux with two lossless audio soundtracks?
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  2. Always Watching guns1inger's Avatar
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    It is within spec, so it is allowable. Can ffmpeg do it ? Don't know.

    Remember, however, that PCM is 1500+ kbps per track, so you have to encode your video to take the extra size into account.

    How long is your video and what is the bitrate ?
    Read my blog here.
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  3. Member
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    There should be enough room to keep it within 4.36gb because the source was about 3gb. It's 01:26:24 and 5.29mbps. The source audio unfortunately was AC3@192 I think. I demuxed to AIFF and did my thing on it converting that to WAV. Could the new mux have the origional AC3 on one track and the remastered as LPCM on another?
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  4. Always Watching guns1inger's Avatar
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    Again - it is within the spec to do this.
    Read my blog here.
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  5. Member
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    Thanks. The only tools I think I have to mux two audio files automatically compress the files. What tools would allow dual PCM muxing to VIDEO_TS? Do you know?
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  6. Always Watching guns1inger's Avatar
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    Unfortunately, I don't use a Mac or know Mac tools well enough. DVD Author should be able to do it, and there is a GUI front-end called Sizzle that might allow it. SmallDVD is also a DVD Author frontend you could look at.
    Read my blog here.
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  7. Originally Posted by cleantone
    What tools would allow dual PCM muxing to VIDEO_TS?
    I often have bad results with PCM (too high bitrate like said by guns1inger). I almost never succeed to mux 2 PCM audio (failure with DVD norm)
    It's 01:26:24 and 5.29mbps.
    5,29 Variable Bit Rate !!! (I don't think you will succeed to mux 2 PCM)

    about muxing: the soft in my sign (Menu "Windows"->"Mux") will allow you to mux m2v and real DVD-PCM(s) (for free, no need to register )…but success depends on the resulting bitrate
    PS: WAV file is not PCM, wav is a special PCM wrapped in "wav"
    and AIFF files are almost DVD-PCM compatible (but wrapped too, not relly wrapped, but with some non-compatible headers

    conclusion: Your audio was compressed (AC3 192kb/s), so you decompressed it (no loose but no gain). Why do you want to keep it as "PCM"???? Convert your audio file to ac3 stéréo 224kb and you'll be sure to loose nothing.

    bye
    For DVD, iPad, HD, connected TV, … iMovie & FCPX? MovieConverter-Studio 3 (01/24/2015) - Handle your camcorder's videos? even in 60p or 60i? do a slow-motion? MovieCam.
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  8. Member
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    Thanks. The loss would be AC3>WAV>AC3(or mp3). The 2nd AC3(or mp3) conversion would be more lossy. I'll check out the software you mention.
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  9. Always Watching guns1inger's Avatar
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    Why did you convert the audio to begin with ?
    Read my blog here.
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  10. Member
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    I didn't.
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  11. Originally Posted by cleantone
    Thanks. The loss would be AC3>WAV>AC3(or mp3). The 2nd AC3(or mp3) conversion would be more lossy
    "not really"
    the first compression (from original to AC3, removed part of frequencies)
    AC3->WAV->AC3 does not change a lot (your WAV file is still "reduced")

    bye
    For DVD, iPad, HD, connected TV, … iMovie & FCPX? MovieConverter-Studio 3 (01/24/2015) - Handle your camcorder's videos? even in 60p or 60i? do a slow-motion? MovieCam.
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  12. Member
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    AC3 is a lossy conversion is it not? Assuming it is, the origional source was converted to AC3. Loss. That was converted to WAV with no loss. The WAV that comes from a lossy source is then reinterpreted to AC3 making a lossy copy of a lossy source. Doubly lossy. Unless I am mistaken.
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  13. your right, BUT...
    (sorry I'm not english native, I don't know the good terms so I will use "stupid images" )

    audio compression (to fill information in bitrate) is:
    compress range
    remove some multiples sounds that human ears cannot ear

    think like a box:
    you have a box with a children book (input ac3)
    your box is now OKed to fill with a dictionnary (WAV bitrate) but you still have inside a children book (exactly the same than the previous one)
    you want to reduce the box again (WAV to AC3), you're box can still contains the children book, your 2nd compression is easy (and not so destructive: range and multiples sounds are still destroyed)

    bye
    For DVD, iPad, HD, connected TV, … iMovie & FCPX? MovieConverter-Studio 3 (01/24/2015) - Handle your camcorder's videos? even in 60p or 60i? do a slow-motion? MovieCam.
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  14. Banned
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    Yes, AC3 -> WAV -> AC3 is "double lossy" but if you use a high enough bit rate, can you REALLY and truly tell? Maybe, maybe not. Some people have much more sensitive hearing than others, but you may not necessarily notice any difference. I've had to convert 640 Kbps AC3 to 448 Kbps AC3 to make HD DVDs (yes, I actually have a player) and it sounds fine to me. You should be able to use 2 PCM tracks as long as the maximum video bit rate does not exceed about 6800 Kbps. If it does, you won't be able to do this. The avg. bit rate means nothing here - it is the maximum you have to worry about.
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  15. Video Restorer lordsmurf's Avatar
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    DVDSP would do it on Mac OS X.
    DVDWS2 would do it on Windows.
    Want my help? Ask here! (not via PM!)
    FAQs: Best Blank DiscsBest TBCsBest VCRs for captureRestore VHS
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