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  1. Member
    Join Date
    Mar 2011
    Location
    Paris, France
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    Hello

    I'm using the following commands to slice an MP4 video (video h264 (High) avc1, audio aac mp4a) into four segments, where files must be one hour long at most:
    Code:
    ffmpeg -ss 00:00:00 -i input.mp4 -t 3600 -c:v copy -c:a copy output.1.mp4
    ffmpeg -ss 00:59:50 -i input.mp4 -t 3600 -c:v copy -c:a copy output.2mp4
    ffmpeg -ss 01:59:40 -i input.mp4 -t 3600 -c:v copy -c:a copy output.3.mp4
    ffmpeg -ss 02:59:30 -i input.mp4 -c:v copy -c:a copy output.4.mp4
    The files play OK locally through VLC, but the video sharing server rejets them saying it has a problem encoding them.

    I read that MP4 is able to slice files even on non-keyframes, and simply includes instructions for readers to jump to the right location, so I don't know where to look for an explanation as to why uploads fail. Any idea?

    Thank you.

    ---
    Edit: As a complement, the original MPEG2 file shot with the camcorder was this:
    Code:
    Duration: 03:28:09.98, start: 0.290767, bitrate: 9462 kb/s
        Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv), 720x576 [SAR 64:45 DAR 16:9], max. 9100 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
        Stream #0:1[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
    And here's what I used to convert it to MP4:
    Code:
    ffmpeg.exe -i input.mpg -c:v libx264 -vf "scale=640:-2" -c:a aac -strict experimental -b:a 128k -ac 2 -shortest -f mp4 input.mp4
    Last edited by yetanotherlogin; 18th May 2014 at 14:56.
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  2. What is the error message the server gives you ?

    What does mediainfo (view=>text) say about one of the split segments ?

    If you don't split, but use the same settings just to test a short 1 min sample for upload, does the server accept it with those same ffmpeg libx264 encoding settings ? What I'm trying to get at is: are you sure the splitting is the culprit?

    In the future, if you know you will be splitting, just split beforehand (ie. encode 4 segments). This way you don' t need to overlap either (cuts will be perfect)
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  3. Member
    Join Date
    Mar 2011
    Location
    Paris, France
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    Thanks for the tips. Ultimately, the segments were accepted. I'll encode the parts as you explained above.
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