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  1. Member
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    Search Comp PM
    I am trying to convert a 1080i MPEG2 transport stream (HDTV) to 720p. If I set the video size to 1280x720 with Autosize set to 16:9, I lose the 16:9 flag. If I change the video size to 1280x724, I get the 16:9 flag. Why is that?
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  2. Member
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    Search Comp PM
    Perhaps it's not the 16:9 flag.

    My original file looks like this in MPEG StreamClip:

    Duration: 0:00:49
    Data Size: 97.26 MB
    Bit Rate: 16.46 Mbps

    Video Tracks:
    49 MPEG-2, 1920 × 1080, 16:9, 23.976 fps, 65.00 Mbps, upper field first

    Audio Tracks:
    52 AC3 3/2, 48 kHz, 384 kbps

    The resulting file looks like this:

    Duration: 0:00:49
    Data Size: 71.43 MB
    Bit Rate: 12.17 Mbps

    Video Tracks:
    224 MPEG-2, 1280 × 720, 59.94 fps, 104.86 Mbps, progressive

    Audio Tracks:
    128 AC3 3/2, 48 kHz, 384 kbps

    Where the heck did the 104.86 Mbps come from?
    _
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  3. Member
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    It would appear that I need to set the ffmpeg "maxrate" option, but ffmpegX does not allow for this. I guess I'll have to fiddle around with command line ffmpeg.
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  4. Member
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    If I set the Video size to 1280x720, then Autosize to "Unconstrained", it would appear that I get what I want.

    Edit: No, I definitely need the aspect ratio flag.
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  5. Member
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    Ffmpeg will not set the display aspect ratio flag if the size of the image is 16:9 (the ffmpegX documentation is incorrect when it states "Using 16:9 ratios or presets also apply a 16:9 special flag to mpeg-2 streams."). However, I've discovered that I can set the aspect ratio flag with a hex editor.
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  6. Member
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    Is it possible with any version of ffmpeg to get output with these characteristics?

    MPEG-2, 1280 × 720, 16:9, 59.94 fps, 19.00 Mbps, progressive

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