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• avformat/utils : Redesign scoring in av_find_default_stream_index()

  1er juillet 2015, par Michael Niedermayer

  avformat/utils : Redesign scoring in av_find_default_stream_index()
  This avoids empty streams from being selected if a equivalent non empty one is available
  
  The new system is also clearer and more systematic
  
  This may need finetuning, which should be easy to do ...
  Fixes Ticket2687
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavformat/utils.c

• Meaningful thumbnails for a Video using PHP-FFMpeg (Laravel 5)

  10 juillet 2015, par JungleGenius

  I’m working on a project using Laravel 5 and the PHP-FFmpeg Library.

  Previously someone else asked this question "Meaningful thumbnails for a Video using FFmpeg" that works from the command line.

  However, I want to implement the functional equivalent using the PHP-FFmpeg Library.

  I have scanned both Stack Overflow and the Unit Tests for PHP-FFmpeg to try and figure out the correct syntax, but it is just not jumping out at me.

  So I’m hoping someone with more experience with PHP-FFmpeg can give me some pointers or an example of how to achieve the same results as the command line calls referenced in this post : "Meaningful thumbnails for a Video using FFmpeg".

  Thanks in advance for everyone’s help.

  BTW, This is my first post on Stack Overflow so the site won’t let me post all the relevant links (limit 2) or create a tag for "PHP-FFmpeg".

• Drawing YUV frames with OpenGL on mac

  10 mars 2015, par Oleg

  I’m decoding video with ffmpeg libraries and store decoded frames in array. Now i want to draw these frames on the screen with OpenGL. I googled and found that apple offers to use GL_APPLE_ycbcr_422 format for effective drawing. So i switched decoding frames in ffmpeg to PIX_FMT_YUYV422 format (packed YUV 4:2:2, 16bpp, Y0 Cb Y1 Cr) which seems to be an equivalent of GL_APPLE_ycbcr_422 in OpenGL. Now i’m trying to draw frames on surface with this code :

  GLsizei width = 2, height = 2;
  
  uint8_t data[8] = {128,200,123,10,5,13,54,180}; 
  
  GLuint texture_name;
  
  
  
  glEnable(GL_TEXTURE_RECTANGLE_ARB);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glGenTextures (1,&texture_name);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glBindTexture(GL_TEXTURE_RECTANGLE_ARB, texture_name);
  
  assert(glGetError() == GL_NO_ERROR);    
  
  
  
  glTextureRangeAPPLE(GL_TEXTURE_RECTANGLE_ARB, width * height * 2, (void*)data);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_STORAGE_HINT_APPLE , GL_STORAGE_SHARED_APPLE);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glPixelStorei(GL_UNPACK_CLIENT_STORAGE_APPLE, GL_TRUE);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  // not sure about code above    
  
  
  
  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
  
  assert(glGetError() == GL_NO_ERROR);    
  
  
  
  // end
  
  
  
  glViewport(0, 0,  width,height);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);                    
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGB, width, height, 0,
  
               GL_YCBCR_422_APPLE,GL_UNSIGNED_SHORT_8_8_APPLE,
  
               (void*)data);
  
  assert(glGetError() == GL_NO_ERROR);
  
  
  
  glTexSubImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
  
                  GL_YCBCR_422_APPLE,GL_UNSIGNED_SHORT_8_8_APPLE,
  
                  (void*)data);
  
  assert(glGetError() == GL_NO_ERROR);    
  
  
  
  glMatrixMode(GL_PROJECTION); 
  
  glLoadIdentity();
  
  
  
  glScalef(1.0f, -1.0f, 1.0f);
  
  glOrtho(0, width, 0, height, -1.0, 1.0);
  
  
  
  glMatrixMode(GL_MODELVIEW);
  
  glLoadIdentity();
  
  
  
  glBegin(GL_QUADS);
  
  
  
  glVertex3f(0, 0, -1.0f);
  
  glVertex3f(width, 0, -1.0f);
  
  glVertex3f(width, height, -1.0f);
  
  glVertex3f(0, height, -1.0f);
  
  
  
  glEnd();

  But i don’t see correct frames. Instead i see corrupted pictures of my display. So i understand that my using of OpenGL is not correct and maybe i don’t understand some fundamental things.

  Please, help to correct and to understand my mistakes. If i should RTFM please give me a link that will help me, because i didn’t find any useful info.