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• Revision 33460 : suite a discussion sur spip-dev, mettre le logo et le titre de l’article ...

  2 décembre 2009, par cedric@… — Log

  suite a discussion sur spip-dev, mettre le logo et le titre de l’article dans le meme pour fluidifier la lecture des revues d’ecran

• libavutil : camellia : remove unwanted memory loads

  10 février 2015, par Supraja Meedinti

  libavutil : camellia : remove unwanted memory loads
  lavu       CAMELLIA     size : 1048576  runs :   1024  time :   21.549 +- 0.17
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavutil/camellia.c

• android ffmpeg opengl es render movie

  18 janvier 2013, par broschb

  I am trying to render video via the NDK, to add some features that just aren't supported in the sdk. I am using FFmpeg to decode the video and can compile that via the ndk, and used this as a starting point. I have modified that example and instead of using glDrawTexiOES to draw the texture I have setup some vertices and am rendering the texture on top of that (opengl es way of rendering quad).

  Below is what I am doing to render, but creating the glTexImage2D is slow. I want to know if there is any way to speed this up, or give the appearance of speeding this up, such as trying to setup some textures in the background and render pre-setup textures. Or if there is any other way to more quickly draw the video frames to screen in android ? Currently I can only get about 12fps.

  glClear(GL_COLOR_BUFFER_BIT);
  
  glEnableClientState(GL_VERTEX_ARRAY);
  
  glEnableClientState(GL_TEXTURE_COORD_ARRAY);
  
  glBindTexture(GL_TEXTURE_2D, textureConverted);
  
  
  
  //this is slow
  
  glTexImage2D(GL_TEXTURE_2D, /* target */
  
  0, /* level */
  
  GL_RGBA, /* internal format */
  
  textureWidth, /* width */
  
  textureHeight, /* height */
  
  0, /* border */
  
  GL_RGBA, /* format */
  
  GL_UNSIGNED_BYTE,/* type */
  
  pFrameConverted->data[0]);
  
  
  
  glEnableClientState(GL_TEXTURE_COORD_ARRAY);
  
  glTexCoordPointer(2, GL_FLOAT, 0, texCoords);
  
  glVertexPointer(3, GL_FLOAT, 0, vertices);
  
  glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_BYTE, indices);
  
  glDisableClientState(GL_VERTEX_ARRAY);
  
  glDisableClientState(GL_TEXTURE_COORD_ARRAY);

  EDIT
  I changed my code to initialize a gltextImage2D only once, and modify it with glSubTexImage2D, it didn't make much of an improvement to the framerate.

  I then modified the code to modify a native Bitmap object on the NDK. With this approach I have a background thread that runs that process the next frames and populates the bitmap object on the native side. I think this has potential, but I need to get the speed increased of converting the AVFrame object from FFmpeg into a native bitmap. Below is currently what I am using to convert, a brute force approach. Is there any way to increase the speed of this or optimize this conversion ?

  static void fill_bitmap(AndroidBitmapInfo*  info, void *pixels, AVFrame *pFrame)
  
  {
  
  uint8_t *frameLine;
  
  
  
  int  yy;
  
  for (yy = 0; yy < info->height; yy++) {
  
      uint8_t*  line = (uint8_t*)pixels;
  
      frameLine = (uint8_t *)pFrame->data[0] + (yy * pFrame->linesize[0]);
  
  
  
      int xx;
  
      for (xx = 0; xx < info->width; xx++) {
  
          int out_offset = xx * 4;
  
          int in_offset = xx * 3;
  
  
  
          line[out_offset] = frameLine[in_offset];
  
          line[out_offset+1] = frameLine[in_offset+1];
  
          line[out_offset+2] = frameLine[in_offset+2];
  
          line[out_offset+3] = 0;
  
      }
  
      pixels = (char*)pixels + info->stride;
  
  }
  
  }