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  1. Broadcaster bigass's Avatar
    Join Date: Dec 2006
    Location: Halifax, NS Canada
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    I'm at the tail end of a gruelling render of a six-episode TV series.

    The end product is a series of MXF files, rendered at 35mbps, 1440x1080, 60i. These are the files I'm submitting to the broadcaster.

    The video portion of these master files is encoded with mpeg2, with uncompressed 16/48 audio.

    I'm thinking there must be some kind of simple solution for lifting the audio & video out of the mxf wrapper so I can put author these to a Blu-Ray disc without more rendering or converting. After all, BR wants a high-bitrate mpeg2 -- I have a high-bitrate mpeg2, but in an mxf wrapper.

    To answer the inevitable "why?" -- the MXF files are for the broadcaster, but I'd like to have playable BR to share the show with the crew and talent.

    Thoughts?
    Last edited by bigass; 10th Mar 2014 at 14:27.
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  2. Member
    Join Date: Sep 2007
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    Not all varieties of "high bitrate mpeg2" are compliant with blu-ray

    What does mediainfo (view=>text) say about the files ?

    If the mpeg2 is compliant then you can just demux the audio & video for import into your authoring program . You can use ffmpeg to demux
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  3. Broadcaster bigass's Avatar
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    Looking at this site's "what is blu-ray" article, I think I'm out of luck. Under "Video frame size" it says "1440x1080x59.94i, 50i (16:9) AVC / VC-1 only."

    So, looks like a re-render's in my future.
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  4. Member Cornucopia's Avatar
    Join Date: Oct 2001
    Location: Deep in the Heart of Texas
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    From what I read of "BD Demystified", MP@H1440L @59.94 MPEG2 is a valid profile. Of course, there are other requisites to that (VBV, GOP, colorspace etc)

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  5. Member
    Join Date: Sep 2007
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    That's outdated information from an early BD draft specification white paper (2005), and baldrick should update it

    You can check directly from the bd association, the revised version shows the change

    Common modern authoring programs (e.g. encore, dvda) allow it as well
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  6. Broadcaster bigass's Avatar
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    Thanks, Cornucopia. Other guides I've searched also said mpeg2 was ok for that resolution.

    When I get back to the studio, I'll post the mediainfo assessment and someone can nix or greenlight my quest.

    If it saves any time, the files were rendered from Sony Vegas 12 with its MXF template, 35mbps, quality slider at 25 (out of 31). Vegas doesn't offer other options on that one.
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  7. Member
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    If it's using a XDCAM-EX preset then it will be 35Mb/s MPEG2 and BD compliant
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  8. Broadcaster bigass's Avatar
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    Here's what MediaInfo tells me about the file:

    Code:
    General
    Complete name                            : L:\TCW on Eastlink - S01 masters\TCW on Eastlink - S01 E01.mxf
    Format                                   : MXF
    Commercial name                          : XDCAM HD 35
    Format profile                           : OP-1a
    Format settings                          : Closed / Complete
    File size                                : 10.4 GiB
    Duration                                 : 53mn 0s
    Overall bit rate mode                    : Variable
    Overall bit rate                         : 28.2 Mbps
    Encoded date                             : 2014-03-06 02:01:13.000
    Writing application                      : SONY Vegas 12.0.0.726
    Writing library                          : SONY Vegas 12.0.0.726
    
    Video
    ID                                       : 2
    Format                                   : MPEG Video
    Commercial name                          : XDCAM HD 35
    Format version                           : Version 2
    Format profile                           : Main@High
    Format settings, BVOP                    : Yes
    Format settings, Matrix                  : Custom
    Format settings, GOP                     : Variable
    Format_Settings_Wrapping                 : Frame
    Duration                                 : 53mn 0s
    Bit rate mode                            : Variable
    Bit rate                                 : 35.0 Mbps
    Width                                    : 1 440 pixels
    Height                                   : 1 080 pixels
    Display aspect ratio                     : 16:9
    Frame rate                               : 29.970 fps
    Standard                                 : Component
    Color space                              : YUV
    Chroma subsampling                       : 4:2:0
    Bit depth                                : 8 bits
    Scan type                                : Interlaced
    Scan order                               : Top Field First
    Compression mode                         : Lossy
    Bits/(Pixel*Frame)                       : 0.751
    Time code of first frame                 : 00:00:00:00
    Time code source                         : Group of pictures header
    Stream size                              : 13.0 GiB
    Color primaries                          : BT.709
    Transfer characteristics                 : BT.709
    Matrix coefficients                      : BT.709
    
    Audio #1
    ID                                       : 3
    Format                                   : PCM
    Format settings, Endianness              : Little
    Format_Settings_Wrapping                 : Frame (AES)
    Duration                                 : 53mn 0s
    Bit rate mode                            : Constant
    Bit rate                                 : 768 Kbps
    Channel(s)                               : 1 channel
    Sampling rate                            : 48.0 KHz
    Bit depth                                : 16 bits
    Stream size                              : 291 MiB (3%)
    
    Audio #2
    ID                                       : 4
    Format                                   : PCM
    Format settings, Endianness              : Little
    Format_Settings_Wrapping                 : Frame (AES)
    Duration                                 : 53mn 0s
    Bit rate mode                            : Constant
    Bit rate                                 : 768 Kbps
    Channel(s)                               : 1 channel
    Sampling rate                            : 48.0 KHz
    Bit depth                                : 16 bits
    Stream size                              : 291 MiB (3%)
    
    Other #1
    ID                                       : 1
    Type                                     : Time code
    Format                                   : MXF TC
    Time code of first frame                 : 00:00:00;00
    Time code settings                       : Striped
    
    Other #2
    Type                                     : Time code
    Format                                   : SMPTE TC
    Muxing mode                              : SDTI
    Time code of first frame                 : 00:00:00;00
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  9. Member
    Join Date: Sep 2007
    Location: Canada
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    Video is ok, but your audio has to be stereo
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  10. demux to get audio and then mix it to get stereo audio:
    Code:
    ffmpeg -i video.mxf -map 0:1 -acodec copy -vn left_audio.wav -map 0:2 -acodec copy -vn right_audio.wav
    sox -M left_audio.wav right_audio.wav stereo.wav
    Last edited by _Al_; 10th Mar 2014 at 20:23.
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  11. Member
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    You don't need sox anymore, ffmpeg can mix to stereo from dual mono using 'amerge'

    eg
    Code:
    ffmpeg -i video.mxf -map 0:1 -map 0:2 -c:a:0 pcm_s16le -c:a:1 pcm_s16le -filter_complex amerge out.wav

    So if you wanted to demux with a batch file to elementary video and combine demuxed to stereo

    Code:
    for %%a in ("*.mxf") do ffmpeg -i "%%a" -c:v copy -an -sn "%%~na.m2v"
    for %%a in ("*.mxf") do ffmpeg -i "%%a"  -map 0:1 -map 0:2 -vn -sn -c:a:0 pcm_s16le -c:a:1 pcm_s16le -filter_complex amerge "%%~na.wav"
    pause
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  12. Member
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    Originally Posted by _Al_ View Post

    but can be PCM part for BD? You might make AC3 out of it, like:
    Code:
    neroAacEnc -lc -cbr 256000 -if "stereo.wav" -of "stereo.m4a

    technically it needs to be LPCM, but most authoring programs will accept PCM

    neroAAC must be a typo

    You can just change the commandline in ffmpeg to encode AC3
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  13. well, habits , good to hear that ffmpeg would do it all

    oh, I see, that is a nonsense, that would be AC3 needed, , I take it down from above post
    Last edited by _Al_; 10th Mar 2014 at 20:23.
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  14. Broadcaster bigass's Avatar
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    I already have the soundtrack mixed as separate 16/48 stereo wav files peaking at -15db. Authoring software ought to let me pick those once I get the mpeg video demuxed. Worst case scenario, re-rendering the soundtrack to ac3 would not be a big chore at all. My wish is merely to avoid having to re-render the video, since it's been such an ordeal getting Vegas to chew it up and spit it out without vomiting.

    Thanks for your command line wizardry, guys!
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  15. Broadcaster bigass's Avatar
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    ... and if I understand correctly, the command line I'd use in this case for the video would be ...?

    Code:
    ffmpeg -i in.mxf -c copy out.mpg
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  16. Member
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    You need an elementary video stream, not program stream (ie. no container)

    Code:
    ffmpeg -i input.mxf -c:v copy -an -sn output.m2v
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  17. Broadcaster bigass's Avatar
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    Excellent. Thanks, pdr.
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