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• FFmpeg fails to be built for android

  8 septembre 2014, par Andro-Begg

  I'm trying to build FFmpeg for android, everything works just fine until the build of build_android.sh, I get at the end :

  /bin/sh: 1: cd: can't cd to ../ffmpeg-build/armeabi/lib
  make: *** [install-libavresample-shared] Error 2
  make: *** Waiting for unfinished jobs....
  /bin/sh: 1: cd: can't cd to ../ffmpeg-build/armeabi/lib
  make: *** [install-libavutil-shared] Error 2
  /bin/sh: 1: cd: can't cd to ../ffmpeg-build/armeabi/lib
  make: *** [install-libswresample-shared] Error 2
  

  I've been inspecting this for a while but couldn't figure out where the problem is..

  Any help will be very appreciated. Thank you.

• interrupt_callback in ffmpeg

  8 septembre 2014, par chesschi

  I understand that many of the functions provided by the ffmpeg libraries are blocking. In order to control the blocking function to timeout, we can assign a callback function to interrupt_callback.

  static int interrupt_cb(void *ctx) 
  

  What is the optimal value for setting this timeout? What will these blocking functions behave when the timeout value is too small?

  For example, the avformat_open_input may take 1 second to complete and if I set a timer for 500 milliseconds, will it never be able to connect to the RTSP server and return non-zero value?

  What is the best approach to use this callback function?

• How to Render video via openGLES2 with Android NDK

  8 septembre 2014, par wolfz

  I made a apk code with NDK to get video frames by ffmpeg decoding, and rendered to opengles 2.0 , but the screen had nothing to display. so did i make a mistake?

  my opengles2.0 ini code is below：

  static int window_init_display(void)
  {
  EGLint attribs [] = {
    EGL_RED_SIZE,        8,
    EGL_GREEN_SIZE,      8,
    EGL_BLUE_SIZE,       8,
    EGL_ALPHA_SIZE,      8,
    EGL_DEPTH_SIZE,     16,
    EGL_STENCIL_SIZE,    0,
    EGL_SAMPLE_BUFFERS,  0,
    EGL_SAMPLES,         0,
    EGL_SURFACE_TYPE,    EGL_WINDOW_BIT,
    EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
    EGL_NONE
  };
  
  EGLint w, h, format;
  EGLint numConfigs;
  EGLConfig config;
  EGLSurface surface;
  EGLContext context;
  
  EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
  
  eglInitialize(display, 0, 0);
  
  eglChooseConfig(display, attribs, &config, 1, &numConfigs);
  
  eglGetConfigAttrib(display, config, EGL_NATIVE_VISUAL_ID, &format);
  
  ANativeWindow_setBuffersGeometry(g_application->window, 0, 0, format);
  
  surface = eglCreateWindowSurface(display, config, g_application->window, NULL);
  
  eglQuerySurface(display, surface, EGL_WIDTH, &w);    
  eglQuerySurface(display, surface, EGL_HEIGHT, &h);
  LOGI("EGL_WIDTH=%d, EGL_HEIGHT=%d",w,h);
  
  eglBindAPI(EGL_OPENGL_ES_API);
  
  EGLint contextAttrs[] =
  {
     EGL_CONTEXT_CLIENT_VERSION, 2,
     EGL_NONE
  };
  context = eglCreateContext(display, config, NULL, contextAttrs);
  
  if (eglMakeCurrent(display, surface, surface, context) == EGL_FALSE) 
  {         
          LOGW("Unable to eglMakeCurrent");      
          return -1;   
  }
  
  LOGI("OK init EGL !!!!");
  

  My render code is below:

  int m_rgbBufferSize = pPicture->iDisplayWidth*pPicture->iDisplayHeight*4;
  m_rgbBuffer = new unsigned char[m_rgbBufferSize];
  
  struct SwsContext *m_sw_context=NULL;
  m_sw_context = m_dllSwScale.sws_getCachedContext(m_sw_context,
                                                    pPicture->iWidth, pPicture->iHeight, PIX_FMT_YUV420P,
                                                    pPicture->iWidth, pPicture->iHeight, PIX_FMT_RGBA,
                                                    SWS_FAST_BILINEAR, NULL, NULL, NULL);
  
  uint8_t *psrc[] = { pPicture->data[0], pPicture->data[1], pPicture->data[2], 0 };
  int srcStride[] = { pPicture->iLineSize[0], pPicture->iLineSize[1], pPicture->iLineSize[2], 0 };
  uint8_t *dst[]  = { m_rgbBuffer, 0, 0, 0 };
  int dstStride[] = { pPicture->iDisplayWidth*4, 0, 0, 0 };
  m_dllSwScale.sws_scale(m_sw_context, psrc, srcStride, 0, pPicture->iDisplayHeight, dst, dstStride);
  //LOGV("swscale OK");
  glEnable(GL_TEXTURE_2D);
  glPixelStorei(GL_UNPACK_ALIGNMENT,1);
  if(textureid == 0)
      glGenTextures(1, &textureid);
  glActiveTexture(GL_TEXTURE2);
  glBindTexture(GL_TEXTURE_2D, textureid);
  glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 
                  pPicture->iDisplayWidth, pPicture->iDisplayHeight, GL_RGBA, GL_UNSIGNED_BYTE, m_rgbBuffer);
  

• Receiving Raw MPEG2-TS data received over RTSP(RTP) via FFMPEG

  8 septembre 2014, par AGP

  I am trying to read raw MPEG2-TS data packets(188 byte) from an RTSP(RTP) stream. I can not figure how to code a client that opens stream and reads raw data. For other video formats and without raw data handling, it is much easier in ffmpeg.

  How can i code this type of client in ffmpeg ?

  Thanks

• JavaCV on Android : UnsatisfiedLinkError from libjniavdevice.so / dlopen failed cannot locate symbol "av_input_audio_device_next"

  8 septembre 2014, par liorg

  I am trying to work with JavaCV's FFmpegFrameGrabber on Android 4.4.2 / 4.3.1 .

  Inside the onCreate(...) method I am calling:

  FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(path)

  This causes the following runtime error:

  dlopen("/data/app-lib/com.example.testjavacv-1/libjniavdevice.so")
  failed: dlopen failed: cannot locate symbol "av_input_audio_device_next"
  referenced by "libjniavdevice.so"
  

  Other (possible) relevant information:

  1) I have included all the JavaCV .so libraries inside the libs/armeabi and libs/x86 folders.

  2) I have given the application permissions to read/write to external storage and access the camera and microphone.

  3) I am NOT statically loading any of the JavaCV native libraries before instantiating FFmpegFrameGrabber. This is because,

  • Some of the libraries cause runtime exceptions when I attempt to load them statically by myself.
  • I get the impression that JavaCV handles it's own native library loading - for example the error I get ocurrs even though I have not requested to load the jniavdevice.so library and happens only if the ... new FFmpegFrameGrabber(...) ... code is present.

  4) I have taken a look at: https://groups.google.com/forum/#!topic/javacv/bgB5rCv_fVM which seems to address a similar issue, but the suggested solutions don't seem to work.

  Any help on this issue would be much appreciated, Cheers!