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• FFmpeg Auto Level, Auto Color etc similar to YouTube's Auto-Fix

  22 juin 2019, par Umer

  I used to use YouTube Auto-Fix which presumably auto fixed levels, color, contrast and added a bit of vibrance (it was almost always a bit high saturated which i kinda liked).

  I am looking for an alternate in ffmpeg. I tried using -vf pp=al but it only lightens the video.

  Any ideas ?

  P.S. I can do this in Premiere/After Effects but am looking for a ffmpeg solution.

• ffmpeg : how add constant color margin to a video

  24 octobre 2017, par علیرضا

  i have a video and i want to add a black background padding to top and bottom of the video to getting a square output.
  
  is it possible to do this with ffmpeg ?

• ffmpeg : RGB to YUV conversion loses color and scale

  27 avril 2015, par learner

  I am trying to convert RGB frames to YUV420P format in ffmpeg/libav. Following is the code for conversion and also the images before and after conversion. The converted image loses all color information and also the scale changes significantly. Does anybody have idea how to handle this ? I am completely new to ffmpeg/libav !

  // Did we get a video frame?
  
     if(frameFinished)
  
     {
  
         i++;
  
         sws_scale(img_convert_ctx, (const uint8_t * const *)pFrame->data,
  
                   pFrame->linesize, 0, pCodecCtx->height,
  
                   pFrameRGB->data, pFrameRGB->linesize);                   
  
  
  
         //==============================================================
  
         AVFrame *pFrameYUV = avcodec_alloc_frame();
  
         // Determine required buffer size and allocate buffer
  
         int numBytes2 = avpicture_get_size(PIX_FMT_RGB24, pCodecCtx->width,                                 
  
                                            pCodecCtx->height);
  
         uint8_t *buffer = (uint8_t *)av_malloc(numBytes2*sizeof(uint8_t));
  
  
  
         avpicture_fill((AVPicture *)pFrameYUV, buffer, PIX_FMT_RGB24,
  
                         pCodecCtx->width, pCodecCtx->height);
  
  
  
  
  
         rgb_to_yuv_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height,  
  
                                         PIX_FMT_RGB24,
  
                                         pCodecCtx->width,pCodecCtx->height, 
  
                                         PIX_FMT_RGB24,
  
                                         SWS_BICUBIC, NULL,NULL,NULL);
  
  
  
         sws_scale(rgb_to_yuv_ctx, pFrameRGB->data, pFrameRGB->linesize, 0, 
  
                   pCodecCtx->height, pFrameYUV->data, pFrameYUV->linesize);
  
  
  
         sws_freeContext(rgb_to_yuv_ctx);
  
  
  
         SaveFrame(pFrameYUV, pCodecCtx->width, pCodecCtx->height, i);
  
  
  
         av_free(buffer);
  
         av_free(pFrameYUV);
  
     }