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• Problems with video length when join video file using ffmpeg concat [migrated]

  27 décembre 2013, par nhanpt

  I have 3 videos, open.avi :duration 0:46:37.885933 , middle.avi : 0:02:56.991927, fin.avi : 0:02:48.199268.
  I try to concat 3 videos using command :

  ffmpeg -i "concat:fin.avi|open.avi|middle.avi" -preset ultrafast -c copy -y vide.avi

  ffmpeg version 1.2.4 Copyright (c) 2000-2013 the FFmpeg developers
  built on Oct 16 2013 22:38:01 with gcc 4.8.1 (GCC) 20130603 (Red Hat 4.8.1-1)
  configuration : —prefix=/usr —bindir=/usr/bin —datadir=/usr/share/ffmpeg —incdir=/usr/include/ffmpeg —libdir=/usr/lib —mandir=/usr/share/man —arch=i686 —optflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector —param=ssp-buffer-size=4 -grecord-gcc-switches -m32 -march=i686 -mtune=atom -fasynchronous-unwind-tables' —enable-bzlib —disable-crystalhd —enable-frei0r —enable-gnutls —enable-libass —enable-libcelt —enable-libdc1394 —disable-indev=jack —enable-libfreetype —enable-libgsm —enable-libmp3lame —enable-openal —enable-libopencv —enable-libopenjpeg —enable-libopus —enable-libpulse —enable-libschroedinger —enable-libspeex —enable-libtheora —enable-libvorbis —enable-libv4l2 —enable-libvpx —enable-libx264 —enable-libxvid —enable-x11grab —enable-avfilter —enable-avresample —enable-postproc —enable-pthreads —disable-static —enable-shared —enable-gpl —disable-debug —disable-stripping —shlibdir=/usr/lib —cpu=i686 —enable-runtime-cpudetect
  libavutil 52. 18.100 / 52. 18.100
  libavcodec 54. 92.100 / 54. 92.100
  libavformat 54. 63.104 / 54. 63.104
  libavdevice 54. 3.103 / 54. 3.103
  libavfilter 3. 42.103 / 3. 42.103
  libswscale 2. 2.100 / 2. 2.100
  libswresample 0. 17.102 / 0. 17.102
  libpostproc 52. 2.100 / 52. 2.100
  Input #0, avi, from 'concat:fin.avi|open.avi|middle.avi' :
  Duration : 00:02:48.20, start : 0.000000, bitrate : 28159 kb/s
  Stream #0:0 : Video : mjpeg (MJPG / 0x47504A4D), yuvj422p, 640x480, 11.20 tbr, 11.20 tbn, 11.20 tbc
  Output #0, avi, to 'vide.avi' :
  Metadata :
  ISFT : Lavf54.63.104
  Stream #0:0 : Video : mjpeg (MJPG / 0x47504A4D), yuvj422p, 640x480, q=2-31, 11.20 tbn, 11.20 tbc
  Stream mapping :
  Stream #0:0 -> #0:0 (copy)
  Press [q] to stop, [?] for help
  frame=27988 fps=2386 q=-1.0 Lsize= 578159kB time=00:41:38.70 bitrate=1895.5kbits/s
  video:577498kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.114549%

  When I change the oder of input video :

  Input #0, avi, from 'concat:open.avi|middle.avi|fin.avi':

  Duration : 00:46:37.89, start : 0.000000, bitrate : 1692 kb/s
  Stream #0:0 : Video : mjpeg (MJPG / 0x47504A4D), yuvj422p, 640x480, 8.61 tbr, 8.61 tbn, 8.61 tbc
  Output #0, avi, to 'vide.avi' :
  Metadata :
  ISFT : Lavf54.63.104
  Stream #0:0 : Video : mjpeg (MJPG / 0x47504A4D), yuvj422p, 640x480, q=2-31, 8.61 tbn, 8.61 tbc
  Stream mapping :
  Stream #0:0 -> #0:0 (copy)
  Press [q] to stop, [?] for help
  frame=27988 fps=2343 q=-1.0 Lsize= 578159kB time=00:54:11.01 bitrate=1456.9kbits/s
  video:577498kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.114549%

  What can I do to fix it ?

• FFMPEG build for android on ubuntu

  23 février 2014, par james

  I am developing a media app which provides support for all video formats for implementing this feature we require FFMPEG the very best library for codecs. Compiling FFMPEG on windows for android is very long battle so I migrated to ubuntu I have almost compiled it shows the the binaries but it gives at last point following message

  >AR libpostproc/libpostproc.a
  
  AR  libswresample/libswresample.a
  
  AR  libswscale/libswscale.a
  
  AR  libavcodec/libavcodec.a
  
  AR  libavutil/libavutil.a
  
  INSTALL libavfilter/libavfilter.a
  
  INSTALL libavformat/libavformat.a
  
  INSTALL libavresample/libavresample.a
  
  INSTALL libpostproc/libpostproc.a
  
  INSTALL libswresample/libswresample.a
  
  INSTALL libswscale/libswscale.a
  
  INSTALL libavutil/libavutil.a
  
  LD  ffmpeg_g
  
  INSTALL libavcodec/libavcodec.a
  
  CP  ffmpeg
  
  STRIP   ffmpeg
  
  skipping strip ffmpeg
  
  INSTALL install-progs-yes
  
  INSTALL ffmpeg
  
  /home/akshay/Desktop/android-ndk-r9c/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86/bin/arm-linux-androideabi-ld: -: unknown option

  Here is my script

  #!/bin/bash
  
  NDK=/home/akshay/Desktop/android-ndk-r9c
  
  PLATFORM=$NDK/platforms/android-8/arch-arm
  
  PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86
  
  PREFIX=./android-ffmpeg
  
  function build_one
  
  {
  
      ./configure --target-os=linux --prefix=$PREFIX \
  
      --enable-cross-compile \
  
      --enable-runtime-cpudetect \
  
      --disable-asm \
  
      --arch=arm \
  
      #--cc=$PREBUILT/bin/arm-linux-androideabi-gcc \
  
      --cross-prefix=$PREBUILT/bin/arm-linux-androideabi- \
  
      --disable-stripping \
  
      #--nm=$PREBUILT/bin/arm-linux-androideabi-nm \
  
      --sysroot=$PLATFORM \
  
      --enable-nonfree \
  
      --enable-version3 \
  
      --disable-everything \
  
      --enable-gpl \
  
      --disable-doc \
  
      --enable-avresample \
  
      --enable-demuxer=rtsp \
  
      --enable-muxer=rtsp \
  
      --disable-ffplay \
  
      --disable-ffserver \
  
      --enable-ffmpeg \
  
      --disable-ffprobe \
  
      --enable-encoders \
  
      --enable-decoders \
  
      --enable-protocols \
  
      --enable-hwaccels \
  
      --enable-zlib \
  
      --disable-devices \
  
      --disable-avdevice \
  
      --extra-cflags="-I/home/android-ffmpeg/include -fPIC -DANDROID -D__thumb__ -mthumb -Wfatal-errors -Wno-deprecated -mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=armv7-a" \
  
      --extra-ldflags="-L/home/android-ffmpeg/lib"
  
      make -j4 install
  
      $PREBUILT/bin/arm-linux-androideabi-ar d libavcodec/libavcodec.a inverse.o
  
      $PREBUILT/bin/arm-linux-androideabi-ld -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -L$PREFIX/lib  -soname libffmpeg.so -shared -  nostdlib  -z,noexecstack -Bsymbolic --whole-archive --no-undefined -o $PREFIX/libffmpeg.so libavcodec/libavcodec.a libavfilter/     libavfilter.a libavresample/libavresample.a libavformat/libavformat.a libavutil/libavutil.a libswscale/libswscale.a -lc -lm -lz -ldl -  llog --warn-once --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.8/libgcc.a
  
  }
  
  build_one

  Please tell me anything wrong in the script

• Video Conferencing in HTML5 : WebRTC via Socket.io

  
  1er janvier 2014, par silvia

  Six months ago I experimented with Web sockets for WebRTC and the early implementations of PeerConnection in Chrome. Last week I gave a presentation about WebRTC at Linux.conf.au, so it was time to update that codebase.

  I decided to use socket.io for the signalling following the idea of Luc, which made the server code even smaller and reduced it to a mere reflector :

   var app = require(’http’).createServer().listen(1337) ;
   var io = require(’socket.io’).listen(app) ;
   io.sockets.on(’connection’, function(socket) 
  
           socket.on(’message’, function(message) 
  
           socket.broadcast.emit(’message’, message) ;
  
       ) ;
  
   ) ;
  

  Then I turned to the client code. I was surprised to see the massive changes that PeerConnection has gone through. Check out my slide deck to see the different components that are now necessary to create a PeerConnection.

  I was particularly surprised to see the SDP object now fully exposed to JavaScript and thus the ability to manipulate it directly rather than through some API. This allows Web developers to manipulate the type of session that they are asking the browsers to set up. I can imaging e.g. if they have support for a video codec in JavaScript that the browser does not provide built-in, they can add that codec to the set of choices to be offered to the peer. While it is flexible, I am concerned if this might create more problems than it solves. I guess we’ll have to wait and see.

  I was also surprised by the need to use ICE, even though in my experiment I got away with an empty list of ICE servers – the ICE messages just got exchanged through the socket.io server. I am not sure whether this is a bug, but I was very happy about it because it meant I could run the whole demo on a completely separate network from the Internet.

  The most exciting news since my talk is that Mozilla and Google have managed to get a PeerConnection working between Firefox and Chrome – this is the first cross-browser video conference call without a plugin ! The code differences are minor.

  Since the specification of the WebRTC API and of the MediaStream API are now official Working Drafts at the W3C, I expect other browsers will follow. I am also looking forward to the possibilities of :

  • multi-peer video conferencing like the efforts around webrtc.io,
  • the media stream recording API,
  • and the peer-to-peer data API.

  The best places to learn about the latest possibilities of WebRTC are webrtc.org and the W3C WebRTC WG. code.google.com has open source code that continues to be updated to the latest released and interoperable features in browsers.

  The video of my talk is in the process of being published. There is a MP4 version on the Linux Australia mirror server, but I expect it will be published properly soon. I will update the blog post when that happens.