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• Revision 3819f11b28 : Use b_width_log2_ in partition type parse Replace mi_width/height_log2 with b_w

  16 mai 2013, par Jingning Han

  Changed Paths :
   Modify /vp9/encoder/vp9_bitstream.c

  
  
  Use b_width_log2_ in partition type parse

  Replace mi_width/height_log2 with b_width/height_log2 in partition
  type parsing at bit-stream writing stage. This allows parsing
  resolution at 4x4 block level and makes the 4x4/4x8/8x4 partition
  coding consistent with other superblock types.

  Change-Id : I7db3617ea042e0db2dc898999b0c323bff91a22f

• What is the best Library/SDK for Realtime 4k video Encoding ?

  2 mai 2013, par Abhishek Bansal

  My requirement is create a encoded video from raw frames in atleast 4k resolution. Presently I am recording videos @1080p using libavcodec (H.264, MPEG4). What will be the best solution for recording these videos @4k ?

  Is it possible to do multithreaded encoding using libavcodec ?
  Another option could be using Intel QuickSync. How good is that ?

  are there other any solutions available ?

  Edit : I require atleast 24FPS.

• C - Transcoding to UDP using FFmpeg ?

  30 avril 2013, par golmschenk

  I'm trying to use the FFmpeg libraries to take an existing video file and stream it over a UDP connection. Specifically, I've been looking at the muxing.c and demuxing.c example files in the source code doc/example directory of FFmpeg. The demuxing file presents code which allows an input video to be converted into the video and audio streams. The muxing file presents code which creates fake data and can already be output to a UDP connection as I would like. I've begun work combining the two. Below can be found my code which is basically a copy of the muxing file with some parts replaced/appended with parts of the demuxing file. Unfortunately I'm running into plenty of complications attempting my goal through this approach. Is there an existing source code example which does the transcoding I'm looking for ? Or at least a tutorial on how one might create this ? If not, at least a few pointers might be helpful in directing my work in combing the two files to achieve my goal. Specifically, I'm getting the error :

  [NULL @ 0x23b4040] Unable to find a suitable output format for 'udp://localhost:7777'
  
  Could not deduce output format from file extension: using MPEG.
  
  Output #0, mpeg, to 'udp://localhost:7777':

  Even though the muxing file could accept UDP formats. Any suggestions ? Thank you much !

  #include 
  
  #include 
  
  #include 
  
  #include 
  
  
  
  #include <libavutil></libavutil>mathematics.h>
  
  #include <libavformat></libavformat>avformat.h>
  
  #include <libswscale></libswscale>swscale.h>
  
  
  
  /* 5 seconds stream duration */
  
  #define STREAM_DURATION   200.0
  
  #define STREAM_FRAME_RATE 25 /* 25 images/s */
  
  #define STREAM_NB_FRAMES  ((int)(STREAM_DURATION * STREAM_FRAME_RATE))
  
  #define STREAM_PIX_FMT    AV_PIX_FMT_YUV420P /* default pix_fmt */
  
  
  
  //FROM DE
  
  static AVFormatContext *fmt_ctx = NULL;
  
  static AVCodecContext *video_dec_ctx = NULL, *audio_dec_ctx;
  
  static AVStream *video_stream = NULL, *audio_stream = NULL;
  
  static const char *src_filename = NULL;
  
  static const char *video_dst_filename = NULL;
  
  static const char *audio_dst_filename = NULL;
  
  static FILE *video_dst_file = NULL;
  
  static FILE *audio_dst_file = NULL;
  
  
  
  static uint8_t *video_dst_data[4] = {NULL};
  
  static int      video_dst_linesize[4];
  
  static int video_dst_bufsize;
  
  
  
  static uint8_t **audio_dst_data = NULL;
  
  static int       audio_dst_linesize;
  
  static int audio_dst_bufsize;
  
  
  
  static int video_stream_idx = -1, audio_stream_idx = -1;
  
  static AVFrame *frame = NULL;
  
  static AVPacket pkt;
  
  static int video_frame_count = 0;
  
  static int audio_frame_count = 0;
  
  //END DE
  
  
  
  static int sws_flags = SWS_BICUBIC;
  
  
  
  /**************************************************************/
  
  /* audio output */
  
  
  
  static float t, tincr, tincr2;
  
  static int16_t *samples;
  
  static int audio_input_frame_size;
  
  
  
  /* Add an output stream. */
  
  static AVStream *add_stream(AVFormatContext *oc, AVCodec **codec,
  
                              enum AVCodecID codec_id)
  
  {
  
      AVCodecContext *c;
  
      AVStream *st;
  
  
  
      /* find the encoder */
  
      *codec = avcodec_find_encoder(codec_id);
  
      if (!(*codec)) {
  
          fprintf(stderr, "Could not find encoder for &#39;%s&#39;\n",
  
                  avcodec_get_name(codec_id));
  
          exit(1);
  
      }
  
  
  
      st = avformat_new_stream(oc, *codec);
  
      if (!st) {
  
          fprintf(stderr, "Could not allocate stream\n");
  
          exit(1);
  
      }
  
      st->id = oc->nb_streams-1;
  
      c = st->codec;
  
  
  
      switch ((*codec)->type) {
  
      case AVMEDIA_TYPE_AUDIO:
  
          st->id = 1;
  
          c->sample_fmt  = AV_SAMPLE_FMT_S16;
  
          c->bit_rate    = 64000;
  
          c->sample_rate = 44100;
  
          c->channels    = 2;
  
          break;
  
  
  
      case AVMEDIA_TYPE_VIDEO:
  
          c->codec_id = codec_id;
  
  
  
          c->bit_rate = 400000;
  
          /* Resolution must be a multiple of two. */
  
          c->width    = 352;
  
          c->height   = 288;
  
          /* timebase: This is the fundamental unit of time (in seconds) in terms
  
           * of which frame timestamps are represented. For fixed-fps content,
  
           * timebase should be 1/framerate and timestamp increments should be
  
           * identical to 1. */
  
          c->time_base.den = STREAM_FRAME_RATE;
  
          c->time_base.num = 1;
  
          c->gop_size      = 12; /* emit one intra frame every twelve frames at most */
  
          c->pix_fmt       = STREAM_PIX_FMT;
  
          if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
  
              /* just for testing, we also add B frames */
  
              c->max_b_frames = 2;
  
          }
  
          if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
  
              /* Needed to avoid using macroblocks in which some coeffs overflow.
  
               * This does not happen with normal video, it just happens here as
  
               * the motion of the chroma plane does not match the luma plane. */
  
              c->mb_decision = 2;
  
          }
  
      break;
  
  
  
      default:
  
          break;
  
      }
  
  
  
      /* Some formats want stream headers to be separate. */
  
      if (oc->oformat->flags &amp; AVFMT_GLOBALHEADER)
  
          c->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
  
  
      return st;
  
  }
  
  
  
  /**************************************************************/
  
  /* audio output */
  
  
  
  static float t, tincr, tincr2;
  
  static int16_t *samples;
  
  static int audio_input_frame_size;
  
  
  
  static void open_audio(AVFormatContext *oc, AVCodec *codec, AVStream *st)
  
  {
  
      AVCodecContext *c;
  
      int ret;
  
  
  
      c = st->codec;
  
  
  
      /* open it */
  
      ret = avcodec_open2(c, codec, NULL);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Could not open audio codec: %s\n", av_err2str(ret));
  
          exit(1);
  
      }
  
  
  
      /* init signal generator */
  
      t     = 0;
  
      tincr = 2 * M_PI * 110.0 / c->sample_rate;
  
      /* increment frequency by 110 Hz per second */
  
      tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
  
  
  
      if (c->codec->capabilities &amp; CODEC_CAP_VARIABLE_FRAME_SIZE)
  
          audio_input_frame_size = 10000;
  
      else
  
          audio_input_frame_size = c->frame_size;
  
      samples = av_malloc(audio_input_frame_size *
  
                          av_get_bytes_per_sample(c->sample_fmt) *
  
                          c->channels);
  
      if (!samples) {
  
          fprintf(stderr, "Could not allocate audio samples buffer\n");
  
          exit(1);
  
      }
  
  }
  
  
  
  /* Prepare a 16 bit dummy audio frame of &#39;frame_size&#39; samples and
  
   * &#39;nb_channels&#39; channels. */
  
  static void get_audio_frame(int16_t *samples, int frame_size, int nb_channels)
  
  {
  
      int j, i, v;
  
      int16_t *q;
  
  
  
      q = samples;
  
      for (j = 0; j &lt; frame_size; j++) {
  
          v = (int)(sin(t) * 10000);
  
          for (i = 0; i &lt; nb_channels; i++)
  
              *q++ = v;
  
          t     += tincr;
  
          tincr += tincr2;
  
      }
  
  }
  
  
  
  static void write_audio_frame(AVFormatContext *oc, AVStream *st)
  
  {
  
      AVCodecContext *c;
  
      AVPacket pkt = { 0 }; // data and size must be 0;
  
      AVFrame *frame = avcodec_alloc_frame();
  
      int got_packet, ret;
  
  
  
      av_init_packet(&amp;pkt);
  
      c = st->codec;
  
  
  
      get_audio_frame(samples, audio_input_frame_size, c->channels);
  
      frame->nb_samples = audio_input_frame_size;
  
      avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
  
                               (uint8_t *)samples,
  
                               audio_input_frame_size *
  
                               av_get_bytes_per_sample(c->sample_fmt) *
  
                               c->channels, 1);
  
  
  
      ret = avcodec_encode_audio2(c, &amp;pkt, frame, &amp;got_packet);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Error encoding audio frame: %s\n", av_err2str(ret));
  
          exit(1);
  
      }
  
  
  
      if (!got_packet)
  
          return;
  
  
  
      pkt.stream_index = st->index;
  
  
  
      /* Write the compressed frame to the media file. */
  
      ret = av_interleaved_write_frame(oc, &amp;pkt);
  
      if (ret != 0) {
  
          fprintf(stderr, "Error while writing audio frame: %s\n",
  
                  av_err2str(ret));
  
          exit(1);
  
      }
  
      avcodec_free_frame(&amp;frame);
  
  }
  
  
  
  static void close_audio(AVFormatContext *oc, AVStream *st)
  
  {
  
      avcodec_close(st->codec);
  
  
  
      av_free(samples);
  
  }
  
  
  
  /**************************************************************/
  
  /* video output */
  
  
  
  static AVFrame *frame;
  
  static AVPicture src_picture, dst_picture;
  
  static int frame_count;
  
  
  
  static void open_video(AVFormatContext *oc, AVCodec *codec, AVStream *st)
  
  {
  
      int ret;
  
      AVCodecContext *c = st->codec;
  
  
  
      /* open the codec */
  
      ret = avcodec_open2(c, codec, NULL);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
  
          exit(1);
  
      }
  
  
  
      /* allocate and init a re-usable frame */
  
      frame = avcodec_alloc_frame();
  
      if (!frame) {
  
          fprintf(stderr, "Could not allocate video frame\n");
  
          exit(1);
  
      }
  
  
  
      /* Allocate the encoded raw picture. */
  
      ret = avpicture_alloc(&amp;dst_picture, c->pix_fmt, c->width, c->height);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Could not allocate picture: %s\n", av_err2str(ret));
  
          exit(1);
  
      }
  
  
  
      /* If the output format is not YUV420P, then a temporary YUV420P
  
       * picture is needed too. It is then converted to the required
  
       * output format. */
  
      if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
  
          ret = avpicture_alloc(&amp;src_picture, AV_PIX_FMT_YUV420P, c->width, c->height);
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Could not allocate temporary picture: %s\n",
  
                      av_err2str(ret));
  
              exit(1);
  
          }
  
      }
  
  
  
      /* copy data and linesize picture pointers to frame */
  
      *((AVPicture *)frame) = dst_picture;
  
  }
  
  
  
  /* Prepare a dummy image. */
  
  static void fill_yuv_image(AVPicture *pict, int frame_index,
  
                             int width, int height)
  
  {
  
      int x, y, i;
  
  
  
      i = frame_index;
  
  
  
      /* Y */
  
      for (y = 0; y &lt; height; y++)
  
          for (x = 0; x &lt; width; x++)
  
              pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
  
  
  
      /* Cb and Cr */
  
      for (y = 0; y &lt; height / 2; y++) {
  
          for (x = 0; x &lt; width / 2; x++) {
  
              pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
  
              pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
  
          }
  
      }
  
  }
  
  
  
  static void write_video_frame(AVFormatContext *oc, AVStream *st)
  
  {
  
      int ret;
  
      static struct SwsContext *sws_ctx;
  
      AVCodecContext *c = st->codec;
  
  
  
      if (frame_count >= STREAM_NB_FRAMES) {
  
          /* No more frames to compress. The codec has a latency of a few
  
           * frames if using B-frames, so we get the last frames by
  
           * passing the same picture again. */
  
      } else {
  
          if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
  
              /* as we only generate a YUV420P picture, we must convert it
  
               * to the codec pixel format if needed */
  
              if (!sws_ctx) {
  
                  sws_ctx = sws_getContext(c->width, c->height, AV_PIX_FMT_YUV420P,
  
                                           c->width, c->height, c->pix_fmt,
  
                                           sws_flags, NULL, NULL, NULL);
  
                  if (!sws_ctx) {
  
                      fprintf(stderr,
  
                              "Could not initialize the conversion context\n");
  
                      exit(1);
  
                  }
  
              }
  
              fill_yuv_image(&amp;src_picture, frame_count, c->width, c->height);
  
              sws_scale(sws_ctx,
  
                        (const uint8_t * const *)src_picture.data, src_picture.linesize,
  
                        0, c->height, dst_picture.data, dst_picture.linesize);
  
          } else {
  
              fill_yuv_image(&amp;dst_picture, frame_count, c->width, c->height);
  
          }
  
      }
  
  
  
      if (oc->oformat->flags &amp; AVFMT_RAWPICTURE) {
  
          /* Raw video case - directly store the picture in the packet */
  
          AVPacket pkt;
  
          av_init_packet(&amp;pkt);
  
  
  
          pkt.flags        |= AV_PKT_FLAG_KEY;
  
          pkt.stream_index  = st->index;
  
          pkt.data          = dst_picture.data[0];
  
          pkt.size          = sizeof(AVPicture);
  
  
  
          ret = av_interleaved_write_frame(oc, &amp;pkt);
  
      } else {
  
          AVPacket pkt = { 0 };
  
          int got_packet;
  
          av_init_packet(&amp;pkt);
  
  
  
          /* encode the image */
  
          ret = avcodec_encode_video2(c, &amp;pkt, frame, &amp;got_packet);
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Error encoding video frame: %s\n", av_err2str(ret));
  
              exit(1);
  
          }
  
          /* If size is zero, it means the image was buffered. */
  
  
  
          if (!ret &amp;&amp; got_packet &amp;&amp; pkt.size) {
  
              pkt.stream_index = st->index;
  
  
  
              /* Write the compressed frame to the media file. */
  
              ret = av_interleaved_write_frame(oc, &amp;pkt);
  
          } else {
  
              ret = 0;
  
          }
  
      }
  
      if (ret != 0) {
  
          fprintf(stderr, "Error while writing video frame: %s\n", av_err2str(ret));
  
          exit(1);
  
      }
  
      frame_count++;
  
  }
  
  
  
  static void close_video(AVFormatContext *oc, AVStream *st)
  
  {
  
      avcodec_close(st->codec);
  
      av_free(src_picture.data[0]);
  
      av_free(dst_picture.data[0]);
  
      av_free(frame);
  
  }
  
  
  
  static int open_codec_context(int *stream_idx,
  
                                AVFormatContext *fmt_ctx, enum AVMediaType type)
  
  {
  
      int ret;
  
      AVStream *st;
  
      AVCodecContext *dec_ctx = NULL;
  
      AVCodec *dec = NULL;
  
  
  
      ret = av_find_best_stream(fmt_ctx, type, -1, -1, NULL, 0);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Could not find %s stream in input file &#39;%s&#39;\n",
  
                  av_get_media_type_string(type), src_filename);
  
          return ret;
  
      } else {
  
          *stream_idx = ret;
  
          st = fmt_ctx->streams[*stream_idx];
  
  
  
          /* find decoder for the stream */
  
          dec_ctx = st->codec;
  
          dec = avcodec_find_decoder(dec_ctx->codec_id);
  
          if (!dec) {
  
              fprintf(stderr, "Failed to find %s codec\n",
  
                      av_get_media_type_string(type));
  
              return ret;
  
          }
  
  
  
          if ((ret = avcodec_open2(dec_ctx, dec, NULL)) &lt; 0) {
  
              fprintf(stderr, "Failed to open %s codec\n",
  
                      av_get_media_type_string(type));
  
              return ret;
  
          }
  
      }
  
  
  
      return 0;
  
  }
  
  
  
  /**************************************************************/
  
  /* media file output */
  
  
  
  int main(int argc, char **argv)
  
  {
  
      const char *filename;
  
      AVOutputFormat *fmt;
  
      AVFormatContext *oc;
  
      AVStream *audio_st, *video_st;
  
      AVCodec *audio_codec, *video_codec;
  
      double audio_pts, video_pts;
  
      int ret = 0, got_frame;;
  
  
  
      /* Initialize libavcodec, and register all codecs and formats. */
  
      av_register_all();
  
  
  
      if (argc != 3) {
  
          printf("usage: %s input_file output_file\n"
  
                 "\n", argv[0]);
  
          return 1;
  
      }
  
  
  
      src_filename = argv[1];
  
      filename = argv[2];
  
  
  
      /* allocate the output media context */
  
      avformat_alloc_output_context2(&amp;oc, NULL, NULL, filename);
  
      if (!oc) {
  
          printf("Could not deduce output format from file extension: using MPEG.\n");
  
          avformat_alloc_output_context2(&amp;oc, NULL, "mpeg", filename);
  
      }
  
      if (!oc) {
  
          return 1;
  
      }
  
      fmt = oc->oformat;
  
  
  
      /* Add the audio and video streams using the default format codecs
  
       * and initialize the codecs. */
  
      video_stream = NULL;
  
      audio_stream = NULL;
  
  
  
      //FROM DE
  
      /* open input file, and allocate format context */
  
      if (avformat_open_input(&amp;fmt_ctx, src_filename, NULL, NULL) &lt; 0) {
  
          fprintf(stderr, "Could not open source file %s\n", src_filename);
  
          exit(1);
  
      }
  
  
  
      /* retrieve stream information */
  
      if (avformat_find_stream_info(fmt_ctx, NULL) &lt; 0) {
  
          fprintf(stderr, "Could not find stream information\n");
  
          exit(1);
  
      }
  
      if (open_codec_context(&amp;video_stream_idx, fmt_ctx, AVMEDIA_TYPE_VIDEO) >= 0) {
  
          video_stream = fmt_ctx->streams[video_stream_idx];
  
          video_dec_ctx = video_stream->codec;
  
  
  
          /* allocate image where the decoded image will be put */
  
          ret = av_image_alloc(video_dst_data, video_dst_linesize,
  
                               video_dec_ctx->width, video_dec_ctx->height,
  
                               video_dec_ctx->pix_fmt, 1);
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Could not allocate raw video buffer\n");
  
              goto end;
  
          }
  
          video_dst_bufsize = ret;
  
      }
  
  
  
      if (open_codec_context(&amp;audio_stream_idx, fmt_ctx, AVMEDIA_TYPE_AUDIO) >= 0) {
  
          int nb_planes;
  
  
  
          audio_stream = fmt_ctx->streams[audio_stream_idx];
  
          audio_dec_ctx = audio_stream->codec;
  
  
  
          nb_planes = av_sample_fmt_is_planar(audio_dec_ctx->sample_fmt) ?
  
              audio_dec_ctx->channels : 1;
  
          audio_dst_data = av_mallocz(sizeof(uint8_t *) * nb_planes);
  
          if (!audio_dst_data) {
  
              fprintf(stderr, "Could not allocate audio data buffers\n");
  
              ret = AVERROR(ENOMEM);
  
              goto end;
  
          }
  
      }
  
      //END DE
  
  
  
      /* Now that all the parameters are set, we can open the audio and
  
       * video codecs and allocate the necessary encode buffers. */
  
      if (video_stream)
  
          open_video(oc, video_codec, video_stream);
  
      if (audio_stream)
  
          open_audio(oc, audio_codec, audio_stream);
  
  
  
      av_dump_format(oc, 0, filename, 1);
  
  
  
      /* open the output file, if needed */
  
      if (!(fmt->flags &amp; AVFMT_NOFILE)) {
  
          ret = avio_open(&amp;oc->pb, filename, AVIO_FLAG_WRITE);
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Could not open &#39;%s&#39;: %s\n", filename,
  
                      av_err2str(ret));
  
              return 1;
  
          }
  
      }
  
  
  
      /* Write the stream header, if any. */
  
      ret = avformat_write_header(oc, NULL);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Error occurred when opening output file: %s\n",
  
                  av_err2str(ret));
  
          return 1;
  
      }
  
  
  
      if (frame)
  
          frame->pts = 0;
  
      for (;;) {
  
          /* Compute current audio and video time. */
  
          if (audio_stream)
  
              audio_pts = (double)audio_stream->pts.val * audio_stream->time_base.num / audio_stream->time_base.den;
  
          else
  
              audio_pts = 0.0;
  
  
  
          if (video_stream)
  
              video_pts = (double)video_stream->pts.val * video_stream->time_base.num /
  
                          video_stream->time_base.den;
  
          else
  
              video_pts = 0.0;
  
  
  
          if ((!audio_stream || audio_pts >= STREAM_DURATION) &amp;&amp;
  
              (!video_stream || video_pts >= STREAM_DURATION))
  
              break;
  
  
  
          /* write interleaved audio and video frames */
  
          if (!video_stream || (video_stream &amp;&amp; audio_st &amp;&amp; audio_pts &lt; video_pts)) {
  
              write_audio_frame(oc, audio_stream);
  
          } else {
  
              write_video_frame(oc, video_stream);
  
              frame->pts += av_rescale_q(1, video_stream->codec->time_base, video_stream->time_base);
  
          }
  
      }
  
  
  
      /* Write the trailer, if any. The trailer must be written before you
  
       * close the CodecContexts open when you wrote the header; otherwise
  
       * av_write_trailer() may try to use memory that was freed on
  
       * av_codec_close(). */
  
      av_write_trailer(oc);
  
  
  
      /* Close each codec. */
  
      if (video_st)
  
          close_video(oc, video_st);
  
      if (audio_st)
  
          close_audio(oc, audio_st);
  
  
  
      if (!(fmt->flags &amp; AVFMT_NOFILE))
  
          /* Close the output file. */
  
          avio_close(oc->pb);
  
  
  
      /* free the stream */
  
      avformat_free_context(oc);
  
  
  
  end:
  
      if (video_dec_ctx)
  
          avcodec_close(video_dec_ctx);
  
      if (audio_dec_ctx)
  
          avcodec_close(audio_dec_ctx);
  
      avformat_close_input(&amp;fmt_ctx);
  
      if (video_dst_file)
  
          fclose(video_dst_file);
  
      if (audio_dst_file)
  
          fclose(audio_dst_file);
  
      av_free(frame);
  
      av_free(video_dst_data[0]);
  
      av_free(audio_dst_data);
  
  
  
      return 0;
  
  }