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• How to get a list of libraries ffmpeg has linked to (static ffmpeg libraries) ?

  22 octobre 2012, par myWallJSON

  I have compiled Ffmpeg (1.0) with newt configuration:

  ./configure  --disable-doc  --disable-ffplay --disable-ffprobe  --disable-ffserver    --disable-avdevice   --disable-avfilter   --disable-pthreads  --disable-everything --enable-muxer=flv --enable-encoder=flv --enable-encoder=h263 --disable-mmx  --disable-shared   --prefix=bin/  --disable-protocols --disable-network --disable-debug  --disable-asm --disable-stripping
  

  It compiled - no errors - headers and libs (static .a) are in place. (special experimental cigwin, experimental gcc, with no asm options, and no known by ffmpeg platform defines) (yet I have compiled and tested boost on it)

  Now I try to compile my app. I get next exceptions:

  ../ffmpeg-1.0/bin/lib/libavcodec.a: error: undefined reference to 'exp'
  ../ffmpeg-1.0/bin/lib/libavcodec.a: error: undefined reference to 'log'
  

  My compiler build line looks like this:

  g++ -static -emit-swf -o CloudClient.swf  -I../boost/boost_libraries/install-dir/include -I../ffmpeg-1.0/bin/include -L../boost/boost_libraries/install-dir/lib -L../ffmpeg-1.0/bin/lib \
      timer.o \
      audio_encoder.o \
      audio_generator.o \
      video_encoder.o \
      video_generator_rainbow.o \
      simple_synchronizer.o \
      multiplexer.o \
      transmitter.o \
      graph_runner.o \
      cloud_client.o \
      -pthread \
      -lswscale \
      -lavutil \
      -lavformat \
      -lavcodec \
      -lboost_system \
      -lboost_date_time \
      -lboost_thread 
  

  So as you see quite complex and I already have all object files compiled and ready... Only one thing left - link it all to ffmpeg (striped from ffmpeg version compiled with boost)

  Tried adding -lm - no help...

  Well here my question is - how to get list of libraries ffmpeg linked to (like -lm etc)?

• FFMpeg crashes on decoding MJpeg

  22 octobre 2012, par Lior Ohana

  I'm working with FFMpeg for decoding Mjpeg streams. Recently I've bumped into access violation exceptions from FFMpeg, after investigating, I found that due to network packet drops, I'm passing to the FFMpeg a frame that might have "gaps" in it. The FFMpeg probably crash since it jumps to a marker payload which doesn't exist in the frame's memory.

  Any idea where I can find a mjpeg structure validator? Is there any way to configure FFMpeg to perform such validations by itself?

  Thanks.

• ffmpeg - How to set MIME-type ? [migrated]

  22 octobre 2012, par sasa

  I'm trying to set the proper MIME-type for an AAC file, but this command does not work:

  ffmpeg -i rain.mp3 -metadata mime-type="audio/aac" rainmp3toaac.aac
  

  but, actualy audio/x-hx-aac-adts is set.

  So, how I can force another MIME-type?

• There is no sound with iFrameExtractor player

  22 octobre 2012, par why

  I has built ffmpeg and iFrameExtractor with ios5.1 successful, But when I play the video, There is no sound

  // Register all formats and codecs
  avcodec_register_all();
  av_register_all();
  avformat_network_init();
  
  
  if(avformat_open_input(&pFormatCtx, [@"http://somesite.com/test.mp4" cStringUsingEncoding:NSASCIIStringEncoding], NULL, NULL) != 0) {
      av_log(NULL, AV_LOG_ERROR, "Couldn't open file\n");
      goto initError;
  }
  

  The log is

  [swscaler @ 0xdd3000] No accelerated colorspace conversion found from
   yuv420p to rgb24. 2012-10-22 20:42:47.344 iFrameExtractor[356:707]
   video duration: 5102.840000 2012-10-22 20:42:47.412
   iFrameExtractor[356:707] video size: 720 x 576 2012-10-22 20:42:47.454
   iFrameExtractor[356:707] Application windows are expected to have a
   root view
  

  This is my configure file for ffmpeg 0.11.1:

  #!/bin/tcsh -f
  
  rm -rf compiled/*
  
  ./configure \
  --cc=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc \
  --as='/usr/local/bin/gas-preprocessor.pl /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc' \
  --sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk \
  --target-os=darwin \
  --arch=arm \
  --cpu=cortex-a8 \
  --extra-cflags='-arch armv7' \
  --extra-ldflags='-arch armv7 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk' \
  --prefix=compiled/armv7 \
  --enable-cross-compile \
  --enable-nonfree \
  --disable-armv5te \
  --disable-swscale-alpha \
  --disable-doc \
  --disable-ffmpeg \
  --disable-ffplay \
  --disable-ffprobe \
  --disable-ffserver \
  --enable-decoder=h264 \
  --enable-decoder=svq3 \
  --disable-asm \
  --disable-bzlib \
  --disable-gpl \
  --disable-shared \
  --enable-static \
  --disable-mmx \
  --disable-neon \
  --disable-decoders \
  --disable-muxers \
  --disable-demuxers \
  --disable-devices \
  --disable-parsers \
  --disable-encoders \
  --enable-protocols \
  --disable-filters \
  --disable-bsfs \
  --disable-postproc \
  --disable-debug 
  

• Playing and recording a live stream from another computer webcam using VLC/FFmpeg [closed]

  22 octobre 2012, par user573014

  I was trying lately to set a video server on one machine and play it in a differen machine, it works with me.. but the problem is that it always stuck and become jammed in the middle .. and it is very slow comparing to the original stream.. something like 5 seconds delay which is not acceptable at all! The warning messages I get usually includes something like that: in the client side, which is the one which is jammed

  [0x24d1ab0] ts demux warning: discontinuity received 0x5 instead of 0xe (pid=68)
  [0x7f4340015e50] rtp demux warning: 2 packet(s) lost
  reference picture missing during reorder
  Missing reference picture
  mmco: unref short failure
  Reference 4 >= 4 (H264 - MPEG-4 AVC (part 10)) stopped
  error while decoding MB 34 14, bytestream (575)
  

  and that is the picture of the streaming when it is jammed

  

  and that is what it looks like when it is running smoothly

  

  This is the error message I got on the server

  [0x2513820] main generic debug: auto hidding mouse
  [0x2296230] main mux warning: late buffer for mux input (1840085)
  

  and Finally here is my command line that I am using > on the server :

  vlc -vvv v4l2:///dev/video1:v4l2-width=640:v4l2-height=480 --sout 
  '#duplicate{dst=display,dst="transcode{vcodec=h264,vb=800,ab=128}
  :duplicate{dst=rtp{mux=ts,dst=172.22.2.87,port=50004}'
  

  on the client :

  vlc -vvv rtp://@:50004 
  

  I thought that it might be from VLC or from my command .. I tried different protocol for transmission, with no luck I also tried FFmpeg and I got similar results + warning messages .. I thought then that both of them are using the same libraries in Linux

  here is the command using FFMpeg :

  ffmpeg -f video4linux2 -i /dev/video1 -vcodec libx264 -s 320x240 -pix_fmt 
  yuv420p -vb 200000 -minrate 200000 -maxrate 200000 -bufsize 2000000 -acodec 
  libmp3lame -ab 128k -ar 44100 -ac 2 -f mpegts udp://172.22.2.87:5544 
  

  In conclusion, I would like to find a solution for the latency of the streaming (which is very high) and the jamming problem I appreciate anyone's input, thank you