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• Issues with adding the current timestamp of a video when using FFPLAY

  28 janvier 2023, par lalelarsen1

  Hi i am trying to add to display the current time of the video as an overlay. i have tried to do follow the answer of this previous post : https://superuser.com/questions/968685/how-to-display-current-time-with-the-ffplay-exe but with no luck.

  


  This is my line of code :

  


  "./ffmpeg-2023-01-25-git-2c3107c3e9-full_build/bin/ffplay.exe" -vf "drawtext=fontfile=./consola.ttf:text='%{pts:hms}':fontsize=48:fontcolor=white:box=1:boxborderw=6:boxcolor=black@0.75:x=(w-text_w)/2:y=h-text_h-20" -i "%shadowplays_folder%\%NEWEST_FOLDER%\%NEWEST_FILE%" -autoexit -x "1000" -alwaysontop


  


  This will display the text "hms}" not the time.

  


  the above code works fine if i replace it with a simple string :

  


  "./ffmpeg-2023-01-25-git-2c3107c3e9-full_build/bin/ffplay.exe" -vf "drawtext=fontfile=./consola.ttf:text='test':fontsize=48:fontcolor=white:box=1:boxborderw=6:boxcolor=black@0.75:x=(w-text_w)/2:y=h-text_h-20" -i "%shadowplays_folder%\%NEWEST_FOLDER%\%NEWEST_FILE%" -autoexit -x "1000" -alwaysontop


  


  This will display the text "test"

  


  what am i missing ?

  


• 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);

• Systematic artefacts from 10bit source

  8 janvier 2015, par user3729198

  When encoding from a 10 bit source file, compression / color artifacts appear. From what I can see, the problem lies in the "dc precision" command "-dc". I have tried different combinations and these are my results.

  On HD encodings ”-dc8” will give you nice clean solid colors without artifacts. But gradients and shading will suffer and be rougher.

  On HD encodings ”-dc11” will give you bad compression and color artifacts that look very systematic. But the Gradients look nice and smooth.

  On SD encodings ”-dc8” will give you nice clean solid colors without artifacts. But gradients and shading will suffer and be rougher.

  On SD encodings ”-dc9” will give you bad compression and color artifacts that look very systematic. But the Gradients look nice and smooth.

  Why is this ? And can it be fixed ? From other encoding software’s if I mimic the settings, all the encodings looks nice in all cases. So it seems that there is a bug in ffmpeg.

  Here is an example of the ffmpeg command I use :

  -i INPUT -vcodec mpeg2video -aspect {$aspectRatio} -r 25 -pix_fmt yuv422p -timecode_frame_start 0 -minrate 150000k -maxrate 150000k -b 150000k -intra -flags +cgop -flags2 +ivlc+non_linear_q -dc 11 -sc_threshold 1000000000 -qscale 1 -qmin 1 -qmax 12 -bufsize 47185920 -rc_init_occupancy 47185920 -rc_buf_aggressivity 0.25 -s {$resolution} -vframes {$frameDuration} -an OUTPUT

  If you want to try it yourself, make sure your source is 10bit, like Uncompressed 10 bit YUV.