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  1. Hi

    I'm encoding this video:

    Code:
    Guessed Channel Layout for  Input Stream #0.1 : stereo
    Input #0, avi, from 'input.avi':
      Duration: 00:00:15.00, start: 0.000000, bitrate: 841360 kb/s
        Stream #0:0: Video: rawvideo, bgr24, 1080x1080, 841678 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
        Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, 2 channels, s16, 1536 kb/s
    using the ffmpeg command:

    Code:
    ffmpeg -i input.avi -codec:v libx264 -profile:v baseline -preset slow -pix_fmt yuv420p -r 29.97 -b:v 25000k -threads 0 -acodec libvo_aacenc -ar 44100 output.mp4
    This produces the following video:

    Code:
    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'output.mp4':
      Metadata:
        major_brand     : isom
        minor_version   : 512
        compatible_brands: isomiso2avc1mp41
        encoder         : Lavf57.2.100
      Duration: 00:00:15.04, start: 0.036281, bitrate: 24893 kb/s
        Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 1080x1080, 24794 kb/s, 29.97 fps, 29.97 tbr, 11988 tbn, 59.94 tbc (default)
        Metadata:
          handler_name    : VideoHandler
        Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
        Metadata:
          handler_name    : SoundHandler
    There are no artefacts at this point, but when I upload this mp4 to instagram, I get the following artefact:

    Click image for larger version

Name:	ugly_frame.png
Views:	474
Size:	19.9 KB
ID:	33783

    See for yourself at https://instagram.com/p/73mZSGTCqz/

    What could cause such a monstrosity? Any ideas on how to get a better result?

    Code:
    ffmpeg version N-75458-g198110d Copyright (c) 2000-2015 the FFmpeg developers
      built with gcc 4.9.3 (GCC)
      configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enab
    le-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --ena
    ble-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
      libavutil      55.  2.100 / 55.  2.100
      libavcodec     57.  3.100 / 57.  3.100
      libavformat    57.  2.100 / 57.  2.100
      libavdevice    57.  0.100 / 57.  0.100
      libavfilter     6.  6.100 /  6.  6.100
      libswscale      4.  0.100 /  4.  0.100
      libswresample   2.  0.100 /  2.  0.100
      libpostproc    54.  0.100 / 54.  0.100
    Thanks
    Quote Quote  
  2. DECEASED
    Join Date
    Jun 2009
    Location
    Heaven
    Search Comp PM
    Try a service which sucks less than Instagram or Facebook —
    YouTube, Vimeo, whatever.

    OR upload to a file sharing site, then the loss of quality = zero.
    Quote Quote  
  3. I don't know what sort of bit rate instagram expects, but

    Code:
    -b:v 25000k
    is a pretty fat bit rate. I would try something more parsimonious like 5000 and see if that helps. Plus the sample rate of the audio, 44.1 kHz, is not standard for video and should be 48 kHz.
    Quote Quote  
  4. Isn't the max resolution 640x640?

    Try disabling weightp - a similar decoding error used to happen to other websites

    In ffmpeg libx264 it would be
    -x264opts weightp=0
    Quote Quote  



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