4 Replies Latest reply on May 16, 2012 12:09 PM by Wil Renczes

    Changing setting in MXF export preset

    Gobblor

      Hey,

       

      A client needs the following format:

       

      HD File Delivery Specification

      “Wrapper”

      MXF OP1A

      Video CODEC

      XDCAMHD 422

      Frame Rate

      25 frames per second

      Video Format

      1080i25, interlaced, top field first

      MPEG Profile

      MPEG-2 422P@HL

      Resolution

      1920 x 1080

      GOP

      • 12 frame GOP
      • Closed GOP, every GOP
      • GOP header on every sequence
      • Sequence header on every GOP

      Timecode

      • TC in every GOP header
      • Timecode to start from 00:00:00:00

      Intra_DC_precision

      10 or higher

      Bit Rate

      50 Mb/s Constant Bit Rate

      Audio Format

      • 24 bit depth
      • 48 kHz sampling rate
      • PCM

      Audio Range

      • Peaks -9/10dBfs (6ppm)
      • Average Dialogue - 16dBfs
      • Average Music  -12dBFs
      • Low level  - 24dBS

      Audio tracks 1&2

      Stereo English Language

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

      Premiere Pro CS6 allows most of these options via a preset - but the preset won't allow me to make any further manual changes. The main issue I'm having is that my files are encoding at 15 frame GOP as opposed to the 12 frame GOP they require. I also can't change any of the other GOP settings.

       

      Any suggestions? Thanks!

        • 1. Re: Changing setting in MXF export preset
          Jim_Simon Level 8

          I see nowhere to change the DC Precision either.  You may have to create an Intermediate and use another encoder for this.

          • 2. Re: Changing setting in MXF export preset
            Wil Renczes Adobe Employee

            If you pick the PAL 1080i 422 50 mbit preset, it will automatically set the GOP length to 12.  Only the NTSC 30 fps variants will default to 15.

             

            Cheers

            • 3. Re: Changing setting in MXF export preset
              Gobblor Level 1

              Hi Will - but that doesn't give me:

               

              • Closed GOP, every GOP
              • GOP header on every sequence
              • Sequence header on every GOP

               

              Any further suggestions?

              • 4. Re: Changing setting in MXF export preset
                Wil Renczes Adobe Employee

                GOP headers, sequence headers & sequence extension headers are generated automatically, that's not something you need to toggle on.  The only thing you can't control here is closed GOP on each GOP.  That's not an available option.

                 

                Why is this a requirement, btw?  Almost every MXF file I've ever analyzed is always closed GOP for the first (which it needs to be for the B0/B1 frames to be legit), and open GOP for the rest of the stream.  The few exceptions I've ever seen:  when 3rd party vendors screw up on the MXF wrapper, and the MXF index entries have closed GOP flags marked throughout the file, but in fact the underlying mpeg stream is actually open GOP throughout.

                 

                I'd check back with your client, I think this is an odd requirement.  We have several broadcasters that we work with who have standardized on OP1a MXF delivery and have no issues with the files we're generating.  You might try generating a test file & have them check it against whatever system they're using it with.

                 

                (Feel free to PM me back with additional questions if the client has more questions, I'm the MXF nerd in house.)

                 

                Cheers