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• Revision c8ed36432e : Non-uniform quantization experiment This framework allows lower quantization bi

  4 mars 2015, par Deb Mukherjee

  Changed Paths :
   Modify /configure

  
   Modify /vp9/common/vp9_blockd.h

  
   Modify /vp9/common/vp9_onyxc_int.h

  
   Modify /vp9/common/vp9_quant_common.c

  
   Modify /vp9/common/vp9_quant_common.h

  
   Modify /vp9/common/vp9_rtcd_defs.pl

  
   Modify /vp9/decoder/vp9_decodeframe.c

  
   Modify /vp9/decoder/vp9_detokenize.c

  
   Modify /vp9/encoder/vp9_block.h

  
   Modify /vp9/encoder/vp9_encodemb.c

  
   Modify /vp9/encoder/vp9_encodemb.h

  
   Modify /vp9/encoder/vp9_quantize.c

  
   Modify /vp9/encoder/vp9_quantize.h

  
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  Non-uniform quantization experiment

  This framework allows lower quantization bins to be shrunk down or
  expanded to match closer the source distribution (assuming a generalized
  gaussian-like central peaky model for the coefficients) in an
  entropy-constrained sense. Specifically, the width of the bins 0-4 are
  modified as a factor of the nominal quantization step size and from 5
  onwards all bins become the same as the nominal quantization step size.
  Further, different bin width profiles as well as reconstruction values
  can be used based on the coefficient band as well as the quantization step
  size divided into 5 ranges.

  A small gain currently on derflr of about 0.16% is observed with the
  same paraemters for all q values.
  Optimizing the parameters based on qstep value is left as a TODO for now.

  Results on derflr with all expts on is +6.08% (up from 5.88%).

  Experiments are in progress to tune the parameters for different
  coefficient bands and quantization step ranges.

  Change-Id : I88429d8cb0777021bfbb689ef69b764eafb3a1de

• Merge commit ’e0046bc9c96150fa06146ace9093f06857dd7b23’

  23 mars 2015, par Michael Niedermayer

  Merge commit ’e0046bc9c96150fa06146ace9093f06857dd7b23’
  * commit ’e0046bc9c96150fa06146ace9093f06857dd7b23’ :
  
    movenc : Write the make and model metadata keys for mov style files
  Conflicts :
  
  	libavformat/movenc.c
  Merged-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavformat/movenc.c

• ffmpeg library performance for decoding h.264 for embedded device

  2 avril 2015, par pasifus

  I have some confuse when tried to compile and run decode h.264 on ARM and MIPS architecture.

  I have two embedded devices. I tired to run simple code that read h264 format from file and decode it to h264 in loop in maximum speed (without sleep between frames)

  I found that it too slow in there devices.
  I tested HD video (720p/25fps)

  1. MIPS32® 1004K (700MHz) it was 4 fps average.
  2. Raspberry Pi Model B (700MHz) it also was 4 fps average. (i know that raspberry have GPU to decoding/encoding)

  A also check it on my virtual machine on ubuntu i686 (1300MHz) and it was 200 fps average.

  The question : why it so different preference ? Somebody know how to increase decoding preference on MIPS32® 1004K architecture ?

  #include 
  
  #include 
  
  #include 
  
  #include 
  
  
  
  #include <sys></sys>time.h>
  
  #include 
  
  
  
  #include "libavcodec/avcodec.h"
  
  #include "libavutil/mathematics.h"
  
  
  
  #define INBUF_SIZE 80000
  
  
  
  
  
  static long get_time_diff(struct timeval time_now) {
  
     struct timeval time_now2;
  
     gettimeofday(&amp;time_now2,0);
  
     return time_now2.tv_sec*1.e6 - time_now.tv_sec*1.e6 + time_now2.tv_usec - time_now.tv_usec;
  
  }
  
  
  
  int main(int argc, char **argv)
  
  {
  
      AVCodec *codec;
  
      AVCodecContext *c= NULL;
  
      AVCodecParserContext *parser = NULL;
  
      int frame, got_picture, len2, len;
  
      const char *filename;
  
      FILE *f;
  
      AVFrame *picture;
  
      char *arghwtf = malloc(INBUF_SIZE);
  
      uint64_t in_len;
  
      int pts, dts;
  
      struct timeval t,t2;
  
      float inv_fps = 1e6/23.98;
  
      AVPacket avpkt;
  
  
  
      // register all the codecs
  
      avcodec_register_all();
  
  
  
      // log level
  
      av_log_set_level(AV_LOG_PANIC|AV_LOG_FATAL|AV_LOG_ERROR|AV_LOG_WARNING);
  
  
  
      filename = argv[1];
  
  
  
      av_init_packet(&amp;avpkt);
  
  
  
      printf("Decoding file %s...\n", filename);
  
  
  
      // find the H.264 video decoder
  
      codec = avcodec_find_decoder(CODEC_ID_H264);
  
      if (!codec)
  
      {
  
          fprintf(stderr, "codec not found\n");
  
          exit(1);
  
      }
  
  
  
      c = avcodec_alloc_context3(codec);
  
      picture = avcodec_alloc_frame();
  
  
  
      // skiploopfilter=all
  
      c->skip_loop_filter = 48;
  
  
  
      AVDictionary* dictionary = NULL;
  
      if (avcodec_open2(c, codec, &amp;dictionary) &lt; 0)
  
      {
  
          fprintf(stderr, "could not open codec\n");
  
          exit(1);
  
      }
  
  
  
      // the codec gives us the frame size, in samples
  
      parser = av_parser_init(c->codec_id);
  
      parser->flags |= PARSER_FLAG_ONCE;
  
  
  
      f = fopen(filename, "rb");
  
      if (!f)
  
      {
  
          fprintf(stderr, "could not open %s\n", filename);
  
          exit(1);
  
      }
  
  
  
      frame = 0;
  
      gettimeofday(&amp;t, 0);
  
      if(fread(arghwtf, 1, INBUF_SIZE, f) == 0)
  
      {
  
          exit(1);
  
      }
  
  
  
      in_len = 80000;
  
      gettimeofday(&amp;t2, 0);
  
      while (in_len > 0 &amp;&amp; !feof(f))
  
      {
  
          len = av_parser_parse2(parser, c, &amp;avpkt.data, &amp;avpkt.size, arghwtf, in_len, pts, dts, AV_NOPTS_VALUE);
  
  
  
          len2 = avcodec_decode_video2(c, picture, &amp;got_picture, &amp;avpkt);
  
          if (len2 &lt; 0) {
  
              fprintf(stderr, "Error while decoding frame %d\n", frame);
  
              exit(1);
  
          }
  
  
  
          if (got_picture)
  
          {
  
              fprintf(stderr, "\rDisplaying %c %dx%d :frame %3d (%02d:%03d)...", av_get_picture_type_char(picture->pict_type), c->width, c->height, frame, (int)(get_time_diff(t)/1000000), (int)((get_time_diff(t)/1000)%1000));
  
              fflush(stderr);
  
  
  
              frame++;
  
          }
  
  
  
          memcpy(arghwtf, arghwtf + len, 80000-len);
  
          fread(arghwtf + 80000 - len, 1, len, f);
  
      }
  
  
  
      fclose(f);
  
      avcodec_close(c);
  
      av_free(c);
  
      av_free(picture);
  
      printf("\n");
  
      printf("Avarage fps: %d\n", (int)(((double)frame)/(double)(get_time_diff(t)/1000)*1000));
  
  
  
      return 0;
  
  }