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  1. OK, I've got an mpeg video (recorded on a DVR) from which I need to edit out the ad breaks.
    Unfortunately, some of the points that I need to make the cuts at are between Keyframes.

    So my plan is to do a 'first pass' re-encding of the complete video to create a version with (many) more Keyframes,
    then edit (and re-encode) the copy to produce the final version.

    Obviously I'd rather avoid too much compression loss in these two conversion passes
    so I need a format for the first pass that - as well as creating new Keyframes - will preserve the original video quality.

    I don't mind if this first pass takes all night to run and creates a humongous output file, because it's only temporary.
    I've searched this forum for the subject of high quality re-encoding, but all of the posts are concerned with best quality for a reasonable file size.

    So can anyone suggest an AVIdemux Video Output format which will maximise Keyframes and preserver quality?


    If it helps, here are the stats of the original file:

    Video Total Duration: 02:09:57.120
    Codec 4CC: MPEG
    Image Size: 544 x 576 Aspect Ratio: Unknown (32:17)
    Frame Rate: 25.000 fps Average Bitrate: 1362 kbps
    Pixel format: YUV 4:2:0, 8-bit Color range: Limited (MPEG)
    Color primaries: BT.709 Transfer characteristics: BT.709
    Color space: BT.709

    Audio (1 active track) Total Duration: 02:09:55.656
    Codec: MP2 Channels: Stereo
    Bitrate: 16000 Bps / 128 kbps Frequency: 48000 Hz
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  2. Use any lossless codec - old HuffYUV work very well and without many issues common for his successors.
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  3. If you don't want to deal with lossless, you can use the x264 mezzanine configuration (crf8, all keyframes).

    Once you are done with the edit, you should be able to apply it to the original file:
    - Save the project file
    - edit the source file name
    - then open the project.
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  4. You might as well do it in 1 pass since you're re-encoding anyways - you can cut anywhere since you're not stream copying. ie There is no benefit for an intermediate step - only potential loss of quality and definite loss of time

    Cutting on keyframe boundaries is only necessary for stream copy in editors that do not smart render the format
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  5. If there are only a few cuts to be made, I would agree there is no point dealing with an intermediate file. Do the cuts on the frame you want then reencode.
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