Sur d’autres sites (13690)

• How to link libav* libraries of FFmpeg in my own program ?

  20 août 2019, par zuguorui

  I am new to FFmpeg, now I want to use the FFmpeg codec compenet in my own program. I’ve followed the guide on FFmpeg wiki to complie the libraries the FFmpeg and get them done. But when I compile my own program it always tips ld: library not found for -lavutil or something like this.

  Environment：MacOS 10.14.6

  Compile tool : clang++

  steps :

  (1)Install all needed libraries follow the wiki.

  (2)./configuure --prefix=host --enable-shared --disable-static

  (3)make

  (4)make install, after this step, I got compiled files in dictionary host.

  (5)copy the source code in FFmpeg/doc/examples/decode_audio.c to create a new project, and copy includes and dylib files to my project dictionary. The structure of my project is :

  ./
  
  |----FFmpeg
  
       |----include
  
            |----libavcodec
  
                 |----*headers*
  
            |----libavformat
  
                 |----*headers*
  
            |----libavutil
  
                 |----*headers*
  
       |----lib
  
            |----libavutil.dylib
  
            |----libavcodec.dylib
  
            |----libavformat.dylib
  
  |----main.cpp

  (6)compile the project.

  clang++ *.cpp -L./FFmpeg/lib/ -lavutil -lavformat -lavcodec -I ./FFmpeg/include -o main.out

  But it always fail with tip ld: library not found for -lavutil or something like this. I don’t know why. Do I need to install those libraries in /usr/local dictionary instead of host ? Or I miss some variables when configing or compiling ?

  update：I solved this problem, I copyed the links of dylib files but not dylib itself, which caused this problem. But a new problem rised, when I run the program, it tips dyld: Library not loaded: @executable_path/lib/libavcodec.dylib. Reason: image not loaded.

• FFmpeg ogg - Invalid data found when processing input

  28 juillet 2017, par Earinor

  I am trying to change the framerate of a Video of mine. Below there is the example Input and the Output. I Built ffmpeg myself and I’m pretty sure I miss the right decoder/demuxer but I have no Idea what I need. I thought —enable-libtheora would be enough to enable, muxers, demuxers, encoder and decoder, but apperently there is somehting missing. Does anybody have an idea about this ?

  I have inserted path-to-ffmpeg to make this shorter, the Path itself is okay, so no worries about that.

     *path-to-ffmpeg*\ffmpeg>ffmpeg -i Video.ogg -filter "minterpolate='fps=60'" out.ogg
  
  ffmpeg version 3.3.git Copyright (c) 2000-2017 the FFmpeg developers
  
    built with gcc 6.3.0 (x86_64-posix-seh-rev2, Built by MinGW-W64 project)
  
    configuration: --disable-encoders --disable-decoder=hevc --disable-decoder=raw
  
  video --disable-decoder=ac3 --disable-decoder=flac --disable-decoder=ffwavesynth
  
   --disable-decoder=libcelt --disable-decoder=libgsm --disable-decoder=libilbc --
  
  disable-decoder=libopus --disable-decoder=dvbsub --disable-decoder=dvdsub --disa
  
  ble-hwaccels --disable-parsers --disable-bsfs --disable-protocols --disable-inde
  
  vs --disable-outdevs --disable-devices --disable-filters --disable-muxers --disa
  
  ble-demuxers --enable-muxer=ogg --enable-zlib --enable-libtheora --enable-libvor
  
  bis --enable-shared --enable-encoder=libtheora --enable-encoder=libvorbis --enab
  
  le-demuxer=image2 --enable-filter=framerate --enable-protocol=file --enable-filt
  
  er=minterpolate --enable-filter=scale
  
    libavutil      55. 61.100 / 55. 61.100
  
    libavcodec     57. 93.100 / 57. 93.100
  
    libavformat    57. 72.101 / 57. 72.101
  
    libavdevice    57.  7.100 / 57.  7.100
  
    libavfilter     6. 85.100 /  6. 85.100
  
    libswscale      4.  7.101 /  4.  7.101
  
    libswresample   2.  8.100 /  2.  8.100
  
  Video.ogg: Invalid data found when processing input

• ffmpeg Extract multiple streams from mkv to mp4

  28 mai 2016, par Sebastien Lemichez

  The situation

  I’m working on a everything to high compatibility mp4 app.
  The goal is to pass a video file and get a mp4 file that can be played by almost every player.

  I’m using ffmpeg to do so with this command :

  "ffmpeg -i " + inputPath + " -c:v libx264 -profile:v baseline -level 3.0 -preset ultrafast " + outputPath

  I’m doing it in a c# wrapper and it’s working like a charm.

  The Problem

  The real problem comes with extra streams that you can commonly find in mkv files like extra audio stream and multiple subtitles.

  So my goal is to use ffprobe.exe to get all input streams, extract them into different files and then using mp4box.exe to add them to my high compatibility mp4 file generated by ffmpeg.exe

  What I’ve done so far

  I have managed to get input streams in json with a structure like this :

  "streams":[
  
      {
  
          "index": 0,
  
          "codec_name": "h264",
  
          "codec_type": "video"
  
      },
  
      {
  
          "index": 1,
  
          "codec_name": "aac",
  
          "codec_type": "audio"
  
      },
  
      {
  
          "index": 2,
  
          "codec_name": "subrip",
  
          "codec_type": "subtitle"
  
          "tags":{
  
              "language": "eng"
  
          }
  
      },
  
      {
  
          "index": 3,
  
          "codec_name": "subrip",
  
          "codec_type": "subtitle"
  
          "tags":{
  
              "language": "fre"
  
          }
  
      },
  
      {
  
          "index": 4,
  
          "codec_name": "aac",
  
          "codec_type": "audio"
  
          "tags":{
  
              "language": "fre"
  
              "title": "Commentary"
  
          }
  
      }
  
  ]

  Where I’m stuck

  To extract those extra stream I would need to do something like this :

  ffmpeg -i input.mkv \
  
  -map 0:2 -c copy subtitle-2.srt \
  
  -map 0:3 -c copy subtitle-3.srt \
  
  -map 0:4 -c copy audio-4.aac

  So is there a way to use my ffprobe result to get these file extension because I have a codec_name "subrip" that should be saved in a srt.

  I’m avoiding an hard coded list because if I miss a format it will break. I’m more looking for a ffmpeg or ffprobe associated list I can use.

  English is not my native language so sorry for any misstakes.