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• how to cut video with specific time using c code ffmpeg ?

  17 avril 2017, par Fidona

  I’m using ffmpeg c code to skip some scene on video. so i have a script like this.

  #include <libavutil></libavutil>timestamp.h>
  
  #include <libavformat></libavformat>avformat.h>
  
  #include <libavutil></libavutil>time.h>     // av_gettime()
  
  #include 
  
  
  
  int64_t total = 0;
  
  
  
  static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt, const char *tag, int hours, int mins, int secs, int us, int *time )
  
  {
  
      AVRational *time_base = &amp;fmt_ctx->streams[pkt->stream_index]->time_base;
  
  
  
      total = total + pkt->duration;
  
  
  
  
  
  
  
      *time = av_q2d(*time_base) * pkt->pts ; //ts
  
  }
  
  
  
  int iexclude[50];
  
  int nexclude=0;
  
  
  
  static int inexclude( int v ) {
  
    for( int i=0; i &lt; nexclude;  ) {
  
      if(  iexclude[i] &lt;= v &amp;&amp; v &lt;= iexclude[i+1] )
  
        return 1;
  
      i = i + 2;
  
    }
  
    return 0;
  
  }
  
  
  
  int main(int argc, char **argv)
  
  {
  
      AVOutputFormat *ofmt = NULL;
  
      AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
  
      AVPacket pkt;
  
      const char *in_filename, *out_filename;
  
      char *ex_time, *token;
  
      int ret, i;
  
      int stream_index = 0;
  
      int *stream_mapping = NULL;
  
      int stream_mapping_size = 0;
  
      int hours, mins, secs, us, time, insec;
  
      int tex[ ] = { 1760, 3060, 4500, 4850, 6235 };
  
  
  
  
  
      if (argc &lt; 4 ) {
  
          printf("usage: %s input output  time_exclude\n"
  
                 "API example program to remux a media file with libavformat and libavcodec.\n"
  
                 "The output format is guessed according to the file extension.\n"
  
                 "  time_exclude ex : 29:17-29:26,50:53-51:20 (without space, comma separated) \n", argv[0]);
  
          return 1;
  
      }
  
  
  
      in_filename  = argv[1];
  
      out_filename = argv[2];
  
      ex_time      = argv[3];
  
  
  
      token = strtok( ex_time, ",-" );
  
  
  
     /* walk through other tokens */
  
      while( token != NULL ) 
  
      {
  
        sscanf( token, "%2d:%2d:%2d", &amp;hours, &amp;mins, &amp;secs ) ;
  
        insec = hours*3600 + mins*60 + secs;
  
        iexclude[ nexclude++ ] = insec;
  
  
  
        printf( "%s  -  %2d:%2d:%2d - %6d\n", token, hours, mins, secs,  insec );
  
        token = strtok(NULL, ",-" );
  
      }
  
  
  
      for( int i=0; i&lt;5; i++ )
  
        printf( "%d\n", inexclude( tex[i] ));  
  
  
  
  
  
  
  
      av_register_all();
  
  
  
      if ((ret = avformat_open_input(&amp;ifmt_ctx, in_filename, 0, 0)) &lt; 0) {
  
          fprintf(stderr, "Could not open input file '%s'", in_filename);
  
          goto end;
  
      }
  
  
  
      if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) &lt; 0) {
  
          fprintf(stderr, "Failed to retrieve input stream information");
  
          goto end;
  
      }
  
  
  
      av_dump_format(ifmt_ctx, 0, in_filename, 0);
  
  
  
      avformat_alloc_output_context2(&amp;ofmt_ctx, NULL, NULL, out_filename);
  
      if (!ofmt_ctx) {
  
          fprintf(stderr, "Could not create output context\n");
  
          ret = AVERROR_UNKNOWN;
  
          goto end;
  
      }
  
  
  
      stream_mapping_size = ifmt_ctx->nb_streams;
  
      stream_mapping = av_mallocz_array(stream_mapping_size, sizeof(*stream_mapping));
  
      if (!stream_mapping) {
  
          ret = AVERROR(ENOMEM);
  
          goto end;
  
      }
  
  
  
      ofmt = ofmt_ctx->oformat;
  
  
  
      for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
  
          AVStream *out_stream;
  
          AVStream *in_stream = ifmt_ctx->streams[i];
  
          AVCodecParameters *in_codecpar = in_stream->codecpar;
  
  
  
          if (in_codecpar->codec_type != AVMEDIA_TYPE_AUDIO &amp;&amp;
  
              in_codecpar->codec_type != AVMEDIA_TYPE_VIDEO &amp;&amp;
  
              in_codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE) {
  
              stream_mapping[i] = -1;
  
              continue;
  
          }
  
  
  
          stream_mapping[i] = stream_index++;
  
  
  
          out_stream = avformat_new_stream(ofmt_ctx, NULL);
  
          if (!out_stream) {
  
              fprintf(stderr, "Failed allocating output stream\n");
  
              ret = AVERROR_UNKNOWN;
  
              goto end;
  
          }
  
  
  
          ret = avcodec_parameters_copy(out_stream->codecpar, in_codecpar);
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Failed to copy codec parameters\n");
  
              goto end;
  
          }
  
          out_stream->codecpar->codec_tag = 0;
  
      }
  
      av_dump_format(ofmt_ctx, 0, out_filename, 1);
  
  
  
      if (!(ofmt->flags &amp; AVFMT_NOFILE)) {
  
          ret = avio_open(&amp;ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Could not open output file '%s'", out_filename);
  
              goto end;
  
          }
  
      }
  
  
  
      ret = avformat_write_header(ofmt_ctx, NULL);
  
      if (ret &lt; 0) {
  
          fprintf(stderr, "Error occurred when opening output file\n");
  
          goto end;
  
      }
  
  
  
      int64_t pts = INT64_MIN + 1;
  
      int64_t now;
  
  
  
      AVRational ar;
  
      int loop = 0;
  
  
  
      while (1) {
  
          loop++;
  
          AVStream *in_stream, *out_stream;
  
  
  
          ret = av_read_frame(ifmt_ctx, &amp;pkt);
  
          if (ret &lt; 0)
  
              break;
  
  
  
          in_stream  = ifmt_ctx->streams[pkt.stream_index];
  
          if (pkt.stream_index >= stream_mapping_size ||
  
              stream_mapping[pkt.stream_index] &lt; 0) {
  
              av_packet_unref(&amp;pkt);
  
              continue;
  
          }
  
  
  
          pkt.stream_index = stream_mapping[pkt.stream_index];
  
          out_stream = ofmt_ctx->streams[pkt.stream_index];
  
  
  
          //log_packet(ifmt_ctx, &amp;pkt, "in");
  
  
  
          /* copy packet */
  
          pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
  
          pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
  
          pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
  
          pkt.pos = -1;
  
  
  
          log_packet(ofmt_ctx, &amp;pkt, "out", hours, mins, secs, us, &amp;time );
  
          //if ( time &lt;= 30 || time >= 150 )
  
          if( ! inexclude( time ) )
  
            ret = av_interleaved_write_frame(ofmt_ctx, &amp;pkt);
  
  
  
          if (ret &lt; 0) {
  
              fprintf(stderr, "Error muxing packet\n");
  
              break;
  
          }
  
          av_packet_unref(&amp;pkt);
  
      }
  
  
  
      printf("Loop %d\n", loop );
  
      av_write_trailer(ofmt_ctx);
  
  end:
  
  
  
      avformat_close_input(&amp;ifmt_ctx);
  
  
  
      /* close output */
  
      if (ofmt_ctx &amp;&amp; !(ofmt->flags &amp; AVFMT_NOFILE))
  
          avio_closep(&amp;ofmt_ctx->pb);
  
      avformat_free_context(ofmt_ctx);
  
  
  
      av_freep(&amp;stream_mapping);
  
  
  
      if (ret &lt; 0 &amp;&amp; ret != AVERROR_EOF) {
  
          fprintf(stderr, "Error occurred: %s\n", av_err2str(ret));
  
          return 1;
  
      }
  
  
  
  and the resul
  
  
  
      printf( "Total = %u AV_TIME_BASE=%d\n", total , AV_TIME_BASE );
  
      return 0;
  
  }

  the code is save with the extension .c
  when i compile this code to skip some scene in specific time, the video was skipped, but it stay freeze until the specified time that i input is finished. what should i add on the code to make the freeze scene get cut ?

• Revision 1ff94fea56 : Inline vp9_quantize() in xform_quant(). Cycle times : 4x4 : 151 to 131 cycles

  11 juillet 2013, par Ronald S. Bultje

  Changed Paths :
   Modify /vp9/encoder/vp9_encodemb.c

  
   Modify /vp9/encoder/vp9_quantize.c

  
   Modify /vp9/encoder/vp9_quantize.h

  
  
  Inline vp9_quantize() in xform_quant().

  Cycle times :
  4x4 : 151 to 131 cycles (15% faster)
  8x8 : 334 to 306 cycles (9% faster)
  16x16 : 1401 to 1368 cycles (2.5% faster)
  32x32 : 7403 to 7367 cycles (0.5% faster)

  Total encode time of first 50 frames of bus @ 1500kbps (speed 0)
  goes from 1min39.2 to 1min38.6, i.e. a 0.67% overall speedup.

  Change-Id : I799a49460e5e3fcab01725564dd49c629bfe935f

• FFMPEG get a video duration and create a thumbnail

  14 mars 2018, par M.Izzat

  Currently this is what I use to convert a video into image from python :

  def video_conversion(raw_file):
  
      duration = "ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 input.mp4"
  
      thumbnail_cmd = "ffmpeg -ss 10 -i input.mp4 -vframes 1 output.jpg"
  
      subprocess.call(duration)
  
      return output

  but this will create and Image for every 30 sec of the video duration, what I want is get the video total duration and create athumbnail exactly in the middle of the duration

  e.g : if the video duration is 60 second, create a thumbnail on the 30th second