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  1. I have been given a set of audio files which are AC3 5.1 encoded.

    Is there any way to write these out to a DVD. They are audio only no video. The idea is to play them back on a commercial DVD surround sound system.

    W.
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  2. Originally Posted by Wibbler
    I have been given a set of audio files which are AC3 5.1 encoded.

    Is there any way to write these out to a DVD. They are audio only no video. The idea is to play them back on a commercial DVD surround sound system.

    W.
    No responses

    Anyway, I had a dig around and found an article in Linux Journal that went some way into helping. I now have the AC3 files mplex'd to a series of stills burned onto a DVD.

    MPlayer at the commandline will play the dvd tiltles fine:

    $ mplayer dvd://1

    etc, but when I try to play the DVD with the Mac DVD Player it just exits. I inserted the DVD into my domestic sony DVD player and it appears to play them OK, except that the audio is speeded up a wee bit. I checked the AC3 files out and found that they are 44100 Hz not 48000 Hz so that accounts for the slight speed up.

    I tried to use ffmpegX and ffmpeg from the Terminal, and found that neither will resample the 44100 to 48000 as AC3..

    Any Ideas?

    W.
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  3. Try to use an authoring program like DVDSP which should have enough options for that.
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  4. I would also suggest Roxio Jam. It has tools for burning AC-3 DVD-Audio discs.
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  5. Thanks, but I should really have asked:

    Any ideas which make use of Free or Shareware software.

    Both these products may be very good, but I only intend to do the 1 DVD so any commercial product is bit OTT..

    W.
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  6. Maybe with Sizzle? I think you can define a menu image and background audio with it.
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  7. Originally Posted by major
    Maybe with Sizzle? I think you can define a menu image and background audio with it.
    I have no problem creating a DVD structure, just that the audio is 44100Hz AC3 and the DVD spec need 48000Hz AC3. All I need to do is resample the AC3 audio from 44100 Hz to 48000 Hz.

    W.
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  8. Use "audio file to ac3" preset and set the sampling to 48000.
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  9. Originally Posted by major
    Use "audio file to ac3" preset and set the sampling to 48000.
    Tried that...

    It pops up an applescript box, saying.

    'cant get text item 2 of no video'

    W.
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  10. Not very helpfull..

    W.
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  11. What do you mean, maybe you didn't understand the link? It was intended to say that you should download again ffmpegX, as in the current version the bug you reported above has been fixed.
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  12. Originally Posted by major
    What do you mean, maybe you didn't understand the link? It was intended to say that you should download again ffmpegX, as in the current version the bug you reported above has been fixed.
    I am using 0.0.9s

    W.
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  13. Indeed I uploaded small bugfixes onto a new copy of 0.0.9s at the same download address. You should download ffmpegX again and try again and you will notice that the bug your reported above will not happen again.
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  14. Originally Posted by major
    Indeed I uploaded small bugfixes onto a new copy of 0.0.9s at the same download address. You should download ffmpegX again and try again and you will notice that the bug your reported above will not happen again.
    Okedoke, now it doesn't complain about the lack of video, but it still fails..

    Code:
    /Applications/ffmpegX.app//Contents/Resources/pbpaste | sh
    Encoding started on Fri Jan 28 00:33:30 GMT 2005
    ffmpeg version 0.4.9-pre1, build 4736, Copyright (c) 2000-2004 Fabrice Bellard
      configuration:  --enable-mp3lame --enable-gpl --disable-vhook --enable-ffplay --disable-ffserver --enable-a52 --enable-xvid --enable-faac --enable-faad --enable-amr_nb --enable-amr_wb --enable-pthreads 
      built on Jan  7 2005 02:34:06, gcc: 3.3 20030304 (Apple Computer, Inc. build 1666)
    Input #0, ac3, from '/Movies/Work/AC3/episode-1.ac3':
      Duration: 00:27:34.9, start: 0.000000, bitrate: 448 kb/s
      Stream #0.0: Audio: ac3, 44100 Hz, 5:1, 448 kb/s
    Resampling with input channels greater than 2 unsupported.Can't resample.  Aborting.
    Abort at ffmpeg.c:1567
    sh: line 1:   451 Abort trap              /Applications/ffmpegX.app//Contents/Resources/ffmpeg -i /Movies/Work/AC3/episode-1.ac3 -y -threads 2 -vn -f ac3 -acodec ac3 -ab 448 -ar 48000 -ac 6 -map 0.0:0.0 -benchmark /Movies/Work/AC3/episode-1.ac3.ff.ac3
    W.
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  15. Maybe your source ac3 is stereo and not 5:1?
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  16. Originally Posted by major
    Maybe your source ac3 is stereo and not 5:1?
    No, The source file is AC3 5:1

    This is what mplayer says about it..

    Code:
    Opening audio decoder: [liba52] AC3 decoding with liba52
    Using AltiVec optimized IMDCT transform
    AC3: 5.1 (3f+2r+lfe)  44100 Hz  448.0 kbit/s
    W.
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  17. Member ChrissyBoy's Avatar
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    My understanding is that ffmpeg can passthrough 5.1 AC3 but can only encode/resample to 2.0. Therefore resampling 5.1 is not possible.
    SVCD2DVD v2.5, AVI/MPEG/HDTV/AviSynth/h264->DVD, PAL->NTSC conversion.
    VOB2MPG PRO, Extract mpegs from your DVDs - with you in control!
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  18. In fact it can encode to 5.1, but when resampling it can only go to 2.0.
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  19. Member ChrissyBoy's Avatar
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    Doh! I was close...
    SVCD2DVD v2.5, AVI/MPEG/HDTV/AviSynth/h264->DVD, PAL->NTSC conversion.
    VOB2MPG PRO, Extract mpegs from your DVDs - with you in control!
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  20. would it be possible to split each AC3 5:1 into its component parts, resample each one separately, and then reassemble the bits..?

    W.
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  21. Not easy, as I think ffmpeg can't neither output to multichannel wav. Where did you get that 44100 Hz AC3 from, as it is highly unstandard. I don't know of any simple method right now other than downsampling this file to stereo.
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  22. The AC3 files are episodes of the recent Hitch Hikers Guide to the Galaxy series (Tertiary Phase) and were downloaded from the BBC website.

    They were only available for a short time. I thought at first that the Beeb were going to release them as a DVD but have only released the series as a 3CD set in stereo.

    W.
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  23. I'm running out of hints. Try to take a mpv file, with a black image or an abstract paint, and use the "Mux as.. DVD" tool to mux it with your 41000 Hz AC3 ("Author as DVD" option enabled). It will make a non-standard DVD anyway, but some DVD players will still play it.
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  24. Originally Posted by major
    I'm running out of hints. Try to take a mpv file, with a black image or an abstract paint, and use the "Mux as.. DVD" tool to mux it with your 41000 Hz AC3 ("Author as DVD" option enabled). It will make a non-standard DVD anyway, but some DVD players will still play it.
    I've already done something like that, and my Sony DVD will play it. But since the audio is 44100 not 48000 it all plays back slightly too fast with everyone sounding like pinky and perky ...

    W.

    (Pinky and Perky - two little pigs with a squeaky high pitched voice - A TV programme from when I was a little lad..)
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