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• Revision 1e30547984 : Skip mode search based on reference frame consistency This commit enables the e

  12 août 2014, par Jingning Han

  Changed Paths :
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Skip mode search based on reference frame consistency

  This commit enables the encoder to skip NEARMV and ZEROMV if the
  above and left blocks have identical reference frame, and the
  current reference is different from that. It reduces the runtime
  of speed 3 for test sequences :
  bus cif at 1000 kbps 10064 ms -> 9823 ms
  pedestrian 1080p at 2000 kbps 193078 ms -> 189559 ms

  The compression performance is changed by
  derf -0.085%
  stdhd -0.103%

  Change-Id : If304f26d42e6412152a84c3dd7b02635c38444f4

• getting black and white image after encoding

  16 mai 2012, par user1310596

  I am trying to encode image using ffmpeg library and objective c. I am using following code but I am getting black and white image as the result. Is there something to do with pixel format(PIX_FMT) ? Please help me so that I can get colored image.

  av_register_all();
  
  avcodec_init();
  
  avcodec_register_all();
  
  avformat_alloc_context();
  
  
  
  AVCodec *codec;
  
  AVCodecContext *ctx= NULL;
  
  int out_size, size, outbuf_size;
  
  AVFrame *picture;
  
  uint8_t *outbuf;
  
  unsigned char *flvdata = malloc(sizeof(unsigned char) * 30);
  
  
  
  
  
  outbuf_size = 200000;
  
  outbuf = malloc(outbuf_size);
  
  
  
  
  
  printf("Video encoding\n");
  
  
  
  codec = avcodec_find_encoder(CODEC_ID_FLV1);
  
  if (!codec) {
  
          fprintf(stderr, "codec not found\n");
  
          exit(1);
  
  }
  
  
  
  ctx= avcodec_alloc_context();
  
  picture= avcodec_alloc_frame();
  
  
  
  
  
  ctx->width = 320;
  
  ctx->height = 240;
  
  ctx -> sample_rate = 11025;
  
  ctx -> time_base.den = 1000;
  
  ctx -> time_base.num = 23976;
  
  ctx -> codec_id = CODEC_ID_FLV1;
  
  ctx -> codec_type = CODEC_TYPE_VIDEO;
  
  ctx->pix_fmt = PIX_FMT_YUV420P;
  
  
  
  if (avcodec_open(ctx, codec) < 0) {
  
          fprintf(stderr, "could not open codec\n");
  
          exit(1);
  
  }
  
  
  
  outbuf_size = 100000;
  
  outbuf = malloc(outbuf_size);
  
  size = ctx->width * ctx->height;
  
  
  
  AVFrame* outpic = avcodec_alloc_frame();
  
  int nbytes = avpicture_get_size(PIX_FMT_YUV420P, ctx->width, ctx->height);
  
  
  
  uint8_t* outbuffer = (uint8_t*)av_malloc(nbytes);
  
  
  
  fflush(stdout);
  
  
  
  int numBytes = avpicture_get_size(PIX_FMT_YUV420P, ctx->width, ctx->height);
  
  
  
  UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:@"0.jpg"]];
  
  CGImageRef newCgImage = [image CGImage];
  
  
  
  CGDataProviderRef dataProvider = CGImageGetDataProvider(newCgImage);
  
  CFDataRef bitmapData = CGDataProviderCopyData(dataProvider);
  
  long dataLength = CFDataGetLength(bitmapData);
  
  
  
  uint8_t *buffer = (uint8_t *)av_malloc(dataLength);
  
  buffer = (uint8_t *)CFDataGetBytePtr(bitmapData);
  
  
  
  for(int i = 0; i < dataLength; i++)
  
  {
  
          if((i + 1) % 16 == 1 && i != 1)
  
                  printf("\n");
  
          printf("%X\t",buffer[i]); // getting something different than the     actual hex value of the image
  
  }
  
  
  
  
  
  
  
  outpic -> pts = 0;        
  
  
  
  avpicture_fill((AVPicture*)picture, buffer, PIX_FMT_RGB8, ctx->width, ctx->height);
  
  
  
  avpicture_fill((AVPicture*)outpic, outbuffer, PIX_FMT_YUV420P, ctx->width, ctx->height);
  
  
  
  struct SwsContext* fooContext = sws_getContext(ctx->width, ctx->height, 
  
                                                         PIX_FMT_RGB8, 
  
                                                         ctx->width, ctx->height, 
  
                                                         PIX_FMT_YUV420P, 
  
                                                         SWS_FAST_BILINEAR, NULL, NULL, NULL);
  
  
  
  sws_scale(fooContext, picture->data, picture->linesize, 0, ctx->height, outpic->data, outpic->linesize);
  
  
  
  printf("abcdefghijklmnop");
  
  out_size = avcodec_encode_video(ctx, outbuf, outbuf_size, outpic);
  
  printf("\n\n out_size %d   outbuf_size %d",out_size,outbuf_size);

  Thanks in advance

• Encoding video only FLV

  25 mars 2012, par NadavRub

  I am trying to generate a video only FLV file, I am using :

  1. libx264 + ffmpeg
  2. 30 fps ( fixed )
  3. playback is done using VLC 2.0.1 and flowplayer

  When playing the FLV the frame-rate seems 1 frame per sec, following is the way I cfg ffmpeg :

  AVOutputFormat* fmtOutput = av_oformat_next(0);
  
  while((0 != fmtOutput) && (0 != strcmp(fmtOutput->name, "flv")))
  
      fmtOutput = av_oformat_next(fmtOutput);
  
  m_pFmtCtxOutput          = avformat_alloc_context();
  
  m_pFmtCtxOutput->oformat = fmtOutput;
  
  
  
  AVStream* pOutVideoStream= av_new_stream(m_pFmtCtxOutput, pInVideoStream->id);
  
  AVCodec*  videoEncoder   = avcodec_find_encoder(CODEC_ID_H264);
  
  
  
  pOutVideoStream->codec->width    = 640;
  
  pOutVideoStream->codec->height   = 480;
  
  pOutVideoStream->codec->level    = 30;
  
  pOutVideoStream->codec->pix_fmt  = PIX_FMT_YUV420P;
  
  pOutVideoStream->codec->bit_rate = 3000000;
  
  
  
  pOutVideoStream->cur_dts         = 0;
  
  pOutVideoStream->first_dts       = 0;
  
  pOutVideoStream->index           = 0;
  
  pOutVideoStream->avg_frame_rate  = (AVRational){ 30, 1 };
  
  pOutVideoStream->time_base       =
  
  pOutVideoStream->codec->time_base= (AVRational){ 1, 30000 };
  
  pOutVideoStream->codec->gop_size = 30;
  
  %% Some specific libx264 settings %%
  
  m_dVideoStep                     = 1000;// packet dts/pts is incremented by this amount each frame
  
  
  
  pOutVideoStream->codec->flags   |= CODEC_FLAG_GLOBAL_HEADER;
  
  avcodec_open(pOutVideoStream->codec, videoEncoder);

  The resulting file seems OK, with the exception of the playback frame-rate.
  having in mind that :

  1. pOutVideoStream->avg_frame_rate = (AVRational) 30, 1  ;
  2. pOutVideoStream->time_base = (AVRational) 1, 30000  ;
  3. pOutVideoStream->codec->time_base= (AVRational) 1, 30000  ;
  4. For each frame I increment the dts/pts by 1000

  What am I doing wrong here ? why the file is playing choppy ( 1 fps ) ?

  Any help will be appreciated.

  Nadav at Sophin