Newest 'ffmpeg' Questions - Stack Overflow

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• GIF to video conversion using FFmpeg [on hold]

  12 mai 2018, par Mehmet Kurtgoz

  Hi I want to convert gif file to video file using FFmpeg.

  My library:

  implementation 'com.writingminds:FFmpegAndroid:0.3.2'

  and the way the code is written:

   String[] commands =  { 
       "-i",
       inputfile,
       "-movflags",
       "faststart",
       "-pix_fmt",
       "yuv420p",
       outputFile
   };
  

  I get an error in this code. Other examples on the Internet do not fit into the library I use. Can you help me ?

• Android - Gif to Video convert FFmpeg

  12 mai 2018, par Mehmet Kurtgoz

  Hi I want to convert gif file to video file using FFmpeg.

  My library:

  implementation 'com.writingminds:FFmpegAndroid:0.3.2'

  and the way the code is written:

   String[] commands =  { 
                                      "-i",
                                      inputfile,
                                      "-movflags",
                                      "faststart",
                                      "-pix_fmt",
                                      "yuv420p",
                                      outputFile
                              };
  

  I get an error in this code. Other examples on the Internet do not fit into the library I use. Can you help me ?

• Convert video to mp4 format in Asp Core 2

  12 mai 2018, par AlTheSwede

  I have tried MediaToolkit as well as NReco.video converter, both works great on ASP.Net but not in core. I tried using MediaToolkit.NetCore which is in early stage but I have not been able to get it to work on ASP Core 2.

  With MeidaToolkit.NetCore i tried this:

  var inputFile = new MediaFile {Filename = @"C:\Path\To_Video.flv"};

  var outputFile = new MediaFile {Filename = @"C:\Path\To_Save_New_Video.mp4"};

  using (var engine = new Engine())

  { engine.Convert(inputFile, outputFile);}

  But the problem is that ffmpeg.exe is not embedded in library binaries, so you have to pass a path to ffmpeg.exe explicitly in the constructor, which I don't know how to do.

  How can I pass the ffmpeg.exe in the constructor above or is there another free FFmpeg wrapper or similar that I can use in order to convert most common video formats into .mp4 format that works on ASP Core 2.x?

• Auto resize video with ffmpeg based on input video resolution

  12 mai 2018, par Masoud Mohammadi

  I wrote a Bash script to convert all video files in a directory. Some videos are 1280 x 720 resolution, and others are 720 x 1280.

  How can I write a ffmpeg command that converts 1280 x 720 videos to 640 x 360 and 720 x 1280 videos to 360 x 640?

• ffmpeg - duration usage in input text file

  12 mai 2018, par Voicu

  I am trying to use ffmpeg to concatenate video segments with some black screen. To do that I've first generated a blank 10-second video (no audio track) with:

  $ ffmpeg -f lavfi -i color=black:s=320x240:r=1 -f lavfi -i anullsrc -t 10 -vcodec libvpx -an blank.mkv

  I then created the simplest possible scenario within input.txt file (contents below) in order to have three seconds of black screen followed by some video (no audio track):

  file 'blank.mkv'
  duration 3
  file 'video_example.mkv'
  

  And, finally, ran the following ffmpeg command to concat the contents of that input file:

  $ ffmpeg -f concat -i input.txt -codec:v copy -codec:a copy output.mkv

  The issue that I have is that the duration 3 is not considered, so the final video still has ten seconds of black frames (instead of three) followed by my video. And also "Non-monotonous DTS in output stream 0:0 ..." message is shown when using duration x in the file. If I remove duration the warnings are gone and getting the 10-second black screen first output as well.

  Full output of the ffmpeg concat command:

  $ ffmpeg -hide_banner -f concat -i input.txt -codec:v copy -codec:a copy output.mkv
  Input #0, concat, from 'input.txt':
    Duration: N/A, start: 0.000000, bitrate: N/A
      Stream #0:0: Video: vp8, yuv420p(progressive), 320x240, SAR 1:1 DAR 4:3, 1 fps, 1 tbr, 1k tbn, 1k tbc
      Metadata:
        ENCODER         : Lavc57.107.100 libvpx
        DURATION        : 00:00:10.000000000
  File 'output.mkv' already exists. Overwrite ? [y/N] y
  Output #0, matroska, to 'output.mkv':
    Metadata:
      encoder         : Lavf57.83.100
      Stream #0:0: Video: vp8 (VP80 / 0x30385056), yuv420p(progressive), 320x240 [SAR 1:1 DAR 4:3], q=2-31, 1 fps, 1 tbr, 1k tbn, 1k tbc
      Metadata:
        ENCODER         : Lavc57.107.100 libvpx
        DURATION        : 00:00:10.000000000
  Stream mapping:
    Stream #0:0 -> #0:0 (copy)
  Press [q] to stop, [?] for help
  [concat @ 000000000031a440] DTS 3000 < 9000 out of order
  [matroska @ 0000000000328420] Non-monotonous DTS in output stream 0:0; previous: 9000, current: 3000; changing to 9000. This may result in incorrect timestamps in the output file.
  [matroska @ 0000000000328420] Non-monotonous DTS in output stream 0:0; previous: 9000, current: 4001; changing to 9000. This may result in incorrect timestamps in the output file.
  [matroska @ 0000000000328420] Non-monotonous DTS in output stream 0:0; previous: 9000, current: 4998; changing to 9000. This may result in incorrect timestamps in the output file.
  [matroska @ 0000000000328420] Non-monotonous DTS in output stream 0:0; previous: 9000, current: 6004; changing to 9000. This may result in incorrect timestamps in the output file.
  [matroska @ 0000000000328420] Non-monotonous DTS in output stream 0:0; previous: 9000, current: 7002; changing to 9000. This may result in incorrect timestamps in the output file.
  [matroska @ 0000000000328420] Non-monotonous DTS in output stream 0:0; previous: 9000, current: 8005; changing to 9000. This may result in incorrect timestamps in the output file.
  frame= 5794 fps=0.0 q=-1.0 Lsize=    7109kB time=01:37:09.70 bitrate=  10.0kbits/s speed=5.16e+004x
  video:7043kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.926229%
  

  Any idea what am I doing wrong? The warning seems to hint towards the issue here.

  Other possibly useful info:

  $ ffprobe -hide_banner blank.mkv
  Input #0, matroska,webm, from 'blank.mkv':
    Metadata:
      ENCODER         : Lavf57.83.100
    Duration: 00:00:10.00, start: 0.000000, bitrate: 1 kb/s
      Stream #0:0: Video: vp8, yuv420p(progressive), 320x240, SAR 1:1 DAR 4:3, 1 fps, 1 tbr, 1k tbn, 1k tbc (default)
      Metadata:
        ENCODER         : Lavc57.107.100 libvpx
        DURATION        : 00:00:10.000000000
  
  $ ffprobe -hide_banner video_example.mkv
  Input #0, matroska,webm, from 'video_example.mkv':
    Metadata:
      encoder         : GStreamer matroskamux version 1.8.1.1
      creation_time   : 2018-05-04T17:57:04.000000Z
    Duration: 01:37:08.70, start: 15434.269000, bitrate: 9 kb/s
      Stream #0:0(eng): Video: vp8, yuv420p(progressive), 320x240, SAR 1:1 DAR 4:3, 1 fps, 1 tbr, 1k tbn, 1k tbc (default)
      Metadata:
        title           : Video
  
  $ ffmpeg -v
  ffmpeg version 3.4.2 Copyright (c) 2000-2018 the FFmpeg developers
    built with gcc 7.3.0 (GCC)