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  1. I have a couple question that cover a few sub forums. Sorry if this is the wrong forum section and/or if I missed it in a search.

    I have Final Cut Pro and Compressor.
    Normally I use FCP to do all edits and “share” to Blu-ray directly (ac3 audio). That creates a disc image that I then burn in Toast.
    however, in this case I need to use uncompressed wav/aiff audio.
    I can’t figure out a way to do it via FCP. Is there a way to export direct from FCP to blu-ray/disc image with uncompressed audio?
    If not, I want to export to Compressor.

    Does anyone know how many minutes and at what bitrate I can set Compressor too in order for it to create a disc image that I can burn?
    For example...
    60 mins of 1080 video with aiff audio needs a bitrate maximum of ___
    120 mins
    180 mins

    Every time I try, Compressor saves the audio and video as separate files but “fails” when creating the disc image.
    I assume it is an issue of the files being to large because If I do a “test” with a files that’s only a few minutes long, it works but when trying files that are 120-180 mins long it fails.

    TIA for any info/tips/advice/fix
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  2. Member DB83's Avatar
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    This is a not exactly a Mac issue but you might well have more assistance with the softwares posting in the dedicated Mac forum.


    However......


    Aiff is NOT an audio format supported by blu-ray so that in itself may be your problem.


    Blu-ray supports a maximum total bitrate of 48 Mbit/s of video + audio. A single PCM audio stream will be 1536 kb/s. 180 mins !!. Well I currently play a single disk that has 170 mins of video/audio. Of course a single-layer disk will hold much less than that.
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  3. Originally Posted by DB83 View Post
    This is a not exactly a Mac issue but you might well have more assistance with the softwares posting in the dedicated Mac forum.


    However......


    Aiff is NOT an audio format supported by blu-ray so that in itself may be your problem.


    Blu-ray supports a maximum total bitrate of 48 Mbit/s of video + audio. A single PCM audio stream will be 1536 kb/s. 180 mins !!. Well I currently play a single disk that has 170 mins of video/audio. Of course a single-layer disk will hold much less than that.
    Thanks for the reply.
    I will look at cross posting to the Mac forum too.

    I am using single layer discs
    Compressor states it is PCM audio when using wav/aiff. I am trying it again now with wav vs aiff but aiff works when I export a short test clip. Do you have a suggestion for an audio format that is uncompressed and supported by blu-ray?
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  4. Member DB83's Avatar
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    Read the 'What is' link at top of this page.


    PCM is the only uncompressed audio format that blu-ray (and dvd for that matter) supports. All other supported formats are compressed.


    Of course this only applies to actual blu-ray media. If you just want locally playable files you have greater flexibility.


    Coming back to your original question it is a case of trial and error when using a bitrate calculator. Your single-layer disk will hold appr. 25 gb. Maximum video bitrate is 40 MBit/s. But the blu ray spec does not state a minimum video bitrate. And while you could get perfectably acceptable 1080p video at 5 MBit/s on a PC a blu-ray player might refuse to play it. So I suggest you look more towards 20-25 MBit/s minimum.
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  5. Member Cornucopia's Avatar
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    Both DVD and Blu-ray support LPCM, and the better authoring/muxing software ought to allow for both WAV & AIFF as input formats to the encoder, as it is literally just a stripping of the headers/metadata and using the raw LPCM streams within them (assuming you are NOT using compressed forms of WAV or AIFF - there are some out there). The only difference between WAV and AIFF internally with their datastreams is that WAV stores the stream little-endian and AIFF stores it Big-endian. IIRC, DVD/BD store it Big-endian as well.

    I agree w/ DB83, use a bitrate calc setting the audio to 1536kbps (2ch * 48000samples/sec * 16bit/channel/sample). The video will be whatever is left over.


    Scott
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  6. Thanks guys
    I will post in the Mac section too as it seems my issue is more Compressor related at this point because I can get it to export a .img file however the audio is muted when trying to use .wav audio
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