Recherche avancée

Sur d’autres sites (13072)

• Render FFmpeg AVFrame as OpenGL texture ?

  5 mars 2019, par ZeroDefect

  I’m attempting to to render a jpeg image (1024x1024 pixels) in the form of an FFmpeg AVFrame as a texture in OpenGL. What I get instead is something that appears as a 1024x1024 dark green quad :

  

  The code to render the AVFrame data in OpenGL is shown below. I have convinced myself that the raw RGB data held within the FFmpeg AVFrame data is not solely dark green.

  GLuint g_texture = {};
  
  
  
  //////////////////////////////////////////////////////////////////////////
  
  void display()
  
  {
  
      // Clear color and depth buffers
  
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  
      glMatrixMode(GL_MODELVIEW);     // Operate on model-view matrix
  
  
  
      glEnable(GL_TEXTURE_2D);
  
      GLuint texture = g_texture;
  
      glBindTexture(GL_TEXTURE_2D, texture);
  
  
  
      // Draw a quad
  
      glBegin(GL_QUADS);
  
      glVertex2i(0, 0); // top left
  
      glVertex2i(1024, 0); // top right
  
      glVertex2i(1024, 1024); // bottom right
  
      glVertex2i(0, 1024); // bottom left
  
      glEnd();
  
  
  
      glDisable(GL_TEXTURE_2D);
  
      glBindTexture(GL_TEXTURE_2D, 0);
  
  
  
      glFlush();
  
  }
  
  
  
  /* Initialize OpenGL Graphics */
  
  void initGL(int w, int h)
  
  {
  
      glViewport(0, 0, w, h); // use a screen size of WIDTH x HEIGHT
  
      glEnable(GL_TEXTURE_2D);     // Enable 2D texturing
  
  
  
      glMatrixMode(GL_PROJECTION);     // Make a simple 2D projection on the entire window
  
      glOrtho(0.0, w, h, 0.0, 0.0, 100.0);
  
      glMatrixMode(GL_MODELVIEW);    // Set the matrix mode to object modeling
  
      //glTranslatef( 0, 0, -15 );
  
  
  
      glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
  
      glClearDepth(0.0f);
  
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear the window
  
  }
  
  
  
  //////////////////////////////////////////////////////////////////////////
  
  int main(int argc, char *argv[])
  
  {
  
      std::shared_ptr<avframe> apAVFrame;
  
      if (!load_image_to_AVFrame(apAVFrame, "marble.jpg"))
  
      {
  
          assert(false);
  
          return 1;
  
      }
  
  
  
      // From here on out, the AVFrame is RGB interleaved
  
      // and is sized to 1,024 x 1,024 (power of 2).
  
  
  
      glutInit(&amp;argc, argv);
  
      glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE);
  
      glutInitWindowSize(1060, 1060);
  
      glutInitWindowPosition(0, 0);
  
      glutCreateWindow("OpenGL - Creating a texture");
  
  
  
      glGenTextures(1, &amp;g_texture);
  
  
  
      //glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  
      glBindTexture(GL_TEXTURE_2D, g_texture);
  
      glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, apAVFrame->width,
  
                   apAVFrame->height, 0, GL_RGB, GL_UNSIGNED_BYTE,
  
                   apAVFrame->data[0]);
  
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); /* We will use linear interpolation for magnification filter */
  
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); /* We will use linear interpolation for minifying filter */
  
  
  
      initGL(1060, 1060);
  
  
  
      glutDisplayFunc(display);
  
  
  
      glutMainLoop();
  
  
  
      return 0;
  
  }
  
  </avframe>

  Environment :

  • Ubuntu 18.04
  • GCC v8.2

  EDIT : As per @immibis’ suggestion below, it all works when I change the rendering of the quad to :

  // Draw a quad
  
  glBegin(GL_QUADS);
  
  glTexCoord2f(0, 0);
  
  glVertex2i(0, 0); // top left
  
  glTexCoord2f(1, 0);
  
  glVertex2i(1024, 0); // top right
  
  glTexCoord2f(1, 1);
  
  glVertex2i(1024, 1024); // bottom right
  
  glTexCoord2f(0, 1);
  
  glVertex2i(0, 1024); // bottom left
  
  glEnd();

• FFMPEG to OpenGL Texture

  23 avril 2014, par Spamdark

  I was here to ask, how can I convert an AVFrame to an opengl texture. Actually, I created a renderer the outputs me the audio (Audio is working) and the video, but the video is not outputing. Here is my code :

  Texture creation :

  glGenTextures(1,&_texture);
  
  glBindTexture(GL_TEXTURE_2D,_texture);
  
  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  
  
  
  glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR ); 
  
  glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );

  Code Info : _texture variable is a GLuint that keeps the texture ID

  Function that gets the AVFrame and convert it to OpenGL Texture :

  int VideoGL::NextVideoFrame(){
  
  // Get a packet from the queue
  
  AVPacket *videopacket = this->DEQUEUE(VIDEO);
  
  int frameFinished;
  
  if(videopacket!=0){
  
      avcodec_decode_video2(_codec_context_video, _std_frame,&frameFinished,videopacket);
  
  
  
      if(frameFinished){
  
  
  
          sws_scale(sws_ctx, _std_frame->data, _std_frame->linesize, 0, _codec_context_video->height, _rgb_frame->data, _rgb_frame->linesize);
  
  
  
          if(_firstrendering){
  
          glBindTexture(GL_TEXTURE_2D,_texture);
  
          glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, _codec_context_video->width,_codec_context_video->height,0,GL_RGB,GL_UNSIGNED_BYTE,_rgb_frame->data[0]);
  
  
  
          _firstrendering = false;
  
  
  
          }else{
  
  
  
              glActiveTexture(_texture);
  
              glBindTexture(GL_TEXTURE_2D,_texture);
  
              glTexSubImage2D(GL_TEXTURE_2D,0,0,0,_codec_context_video->width,_codec_context_video->height,GL_RGB,GL_UNSIGNED_BYTE,_rgb_frame->data[0]);
  
  
  
          }
  
          av_free_packet(videopacket);
  
          return 0;
  
      }else{
  
  
  
          av_free_packet(videopacket);
  
          return -1;
  
      }
  
  
  
  }else{
  
      return -1;
  
  }
  
  return 0;
  
  }

  Code Information : There is a queue where a thread store the AVFrames, this function is frequently called to get the AVFrames, until it gets a NULL it stops to being called.

  That’s actually not working. (I tried to look at some questions in stack overflow, it’s still not working)
  Any example, or someone that helps me to correct any error there ?

  Additional Data : I tried to change the GL_RGB to GL_RGBA and started to play with the formats, anyway it crashes when I try GL_RGBA (Because the width and height are very big, anyway I tried to resize them). I have tried to change the sizes to Power Of 2, stills not working.

  1 Edit :

  Thread function :

  DWORD WINAPI VideoGL::VidThread(LPVOID myparam){
  
  
  
  VideoGL * instance = (VideoGL*) myparam;
  
  instance->wave_audio->Start();
  
  
  
  int quantity=0;
  
  
  
  AVPacket packet;
  
  while(av_read_frame(instance->_format_context,&packet) >= 0){
  
      if(packet.stream_index==instance->videoStream){
  
          instance->ENQUEUE(VIDEO,&packet);
  
      }
  
      if(packet.stream_index==instance->audioStream){
  
          instance->ENQUEUE(AUDIO,&packet);
  
      }
  
  }
  
  
  
  instance->ENQUEUE(AUDIO,NULL);
  
  instance->ENQUEUE(VIDEO,NULL);
  
  
  
  return 0;
  
  }

  Thread creation function :

  CreateThread(NULL, 0, VidThread, this, NULL, NULL);

  Where this refers to the class that contains the NextVideoFrame, and the _texture members.

  Solved :

  I followed some of the datenwolf tips, and now the video is displaying correctly with the audio/video :

  

• Announcing Long Term Support in Piwik 2 – The analytics platform for your mission critical projects

  11 janvier 2016, par Matthieu Aubry — About, Development

  We are proud to announce our Long Term Support (LTS) for Piwik 2.X !

  Why Long Term Support (LTS) ?

  Part of our mission is to ready Piwik for the enterprise — and ready the enterprise for Piwik. Our fast release cycle and our ability to quickly innovate has served us well for the past seven years and has lead Piwik to being one of the most popular open source projects, used by over one million websites worldwide. But Piwik’s success today has also shown us that this fast release cycle is not suited for all users and customers. Like most large open source projects (such as Ubuntu, Firefox, Debian, Symfony, Node.js, etc.) at Piwik we now also offer a Long Term Support release which gives users the confidence that Piwik can be used for mission critical projects for months to come.

  What does LTS mean for Piwik ?

  For the duration of the LTS period, Piwik 2.X will continue to receive the following fixes :

  • Critical bugs causing data loss or data corruption.
  • Major and Critical security issues.

  Our goal is to offer you a Piwik LTS release that you can trust for all your mission critical projects.

  How long will Piwik 2.X be supported ?

  Piwik 2.X will be supported for at least 12 months after the initial release of Piwik 3.0.0.
  Piwik 3.0.0 is expected to be released in the second half of 2016.
  This means that Piwik 2.X will be supported at least until the second half of 2017.

  Which Piwik version is LTS ?

  The latest Piwik 2.16.X release is our Long Term Support version.

  How do I benefit from the LTS version ?

  To get the full benefits of Piwik LTS, please make sure you are using the latest LTS version. First, update to the latest Piwik 2.X version, then Configure Piwik to use the LTS release channel and then update to the latest LTS version.

  How do I configure Piwik to use the LTS version ?

  By default, Piwik will not use the LTS version. When you use the one-click update your Piwik instance will be updated to the very latest release : when Piwik 3.0.0 will be released, the one click update will update your instance to 3.0.0. It is however possible to configure your Piwik so that you will stay on Piwik 2.X and keep using the LTS Long Term Support version :

  • Login Piwik as the Super User,
  • Go to Settings > General > Update settings,
  • Under “Release channel” click “Latest stable 2.X Long Term Support version”, and click “Save”.
    

  How do I get professional Piwik Support ?

  If you need professional support for your Piwik service get in touch with the Piwik PRO experts.

  ---

  For other questions, feedback or discussion, feel free to join our forums and comment on this LTS forum post.

  We wish you all a fantastic year 2016 !