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• avs : support for AviSynth+ high bit-depth pixel formats

  18 août 2016, par Anton Mitrofanov

  avs : support for AviSynth+ high bit-depth pixel formats
  

  • [DH] extras/avisynth_c.h
  • [DH] input/avs.c

• Generating mp4 from images with libavformat has really high framerate

  13 septembre 2016, par Taylor Southwick

  I want to generate video from still shots using libav. I’ve successfully done this when the container is .avi, but I would also like to be able to output it into .mp4. However, when I try to do this, on the initial frame is shown (the .avi version works fine. I’ve created the following repro of the pertinent code using dummy picture generation.

  If you run

  CreateVideo("test.avi", 600, 300);

  It will generate a functional video. However,

  CreateVideo("test.mp4", 600, 300);

  will generate a video, but only a single frame.

  Any thoughts on why it works for .avi but not .mp4 ? Is there a setting I’m missing ?

  extern "C" {
  
  #include <libavformat></libavformat>avformat.h>
  
  #include <libavutil></libavutil>avassert.h>
  
  #include <libavutil></libavutil>channel_layout.h>
  
  #include <libavutil></libavutil>opt.h>
  
  #include <libavutil></libavutil>mathematics.h>
  
  #include <libavutil></libavutil>imgutils.h>
  
  #include <libswscale></libswscale>swscale.h>
  
  #include <libswresample></libswresample>swresample.h>
  
  }
  
  
  
  using namespace std;
  
  using namespace Ffmpeg;
  
  
  
  void AddFrame(AVPacket &amp;pkt, AVCodecContext *codec, AVFormatContext *_avFmtCtx, AVFrame *_frame, int i)
  
  {
  
      // Initialize a packet and clear data as it will be allocated by the encoder
  
      av_init_packet(&amp;pkt);
  
      pkt.data = nullptr;
  
      pkt.size = 0;
  
  
  
      i = i % 25;
  
  
  
      /* prepare a dummy image */
  
      /* Y */
  
      for (int y = 0; y &lt; _frame->height; y++) {
  
          for (int x = 0; x &lt; _frame->width; x++) {
  
              _frame->data[0][y * _frame->linesize[0] + x] = x + y + i * 3;
  
          }
  
      }
  
  
  
      /* Cb and Cr */
  
      for (int y = 0; y &lt; _frame->height / 2; y++) {
  
          for (int x = 0; x &lt; _frame->width / 2; x++) {
  
              _frame->data[1][y * _frame->linesize[1] + x] = 128 + y + i * 2;
  
              _frame->data[2][y * _frame->linesize[2] + x] = 64 + x + i * 5;
  
          }
  
      }
  
  
  
      int got_output;
  
      avcodec_encode_video2(codec, &amp;pkt, _frame, &amp;got_output);
  
  
  
      _frame->pts++;
  
  
  
      if (got_output)
  
      {
  
          av_interleaved_write_frame(_avFmtCtx, &amp;pkt);
  
          av_packet_unref(&amp;pkt);
  
      }
  
  }
  
  
  
  static void CreateVideo(string path, int width, int height)
  
  {
  
      // This will quickly exit if registration has already occurred
  
      av_register_all();
  
  
  
      AVFormatContext *_avFmtCtx;
  
      avformat_alloc_output_context2(&amp;_avFmtCtx, nullptr, nullptr, path.c_str());
  
  
  
      AVCodec *codec = avcodec_find_encoder(_avFmtCtx->oformat->video_codec);
  
      AVStream *_video = avformat_new_stream(_avFmtCtx, codec);
  
  
  
      // Customize codec
  
      _video->codec->coder_type = AVMEDIA_TYPE_VIDEO;
  
      _video->codec->bit_rate = 200000;
  
      _video->codec->width = width;
  
      _video->codec->height = height;
  
      _video->codec->time_base.num = 1;
  
      _video->codec->time_base.den = 15;
  
      _video->codec->gop_size = 12;
  
      _video->codec->pix_fmt = AV_PIX_FMT_YUV420P;
  
  
  
      if (_video->codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)
  
      {
  
          // Just for testing, add B-frames
  
  #ifdef _DEBUG
  
          _video->codec->max_b_frames = 2;
  
  #endif
  
      }
  
  
  
      if (_video->codec->codec_id == AV_CODEC_ID_MPEG1VIDEO)
  
      {
  
          _video->codec->mb_decision = 2;
  
      }
  
  
  
      if (_avFmtCtx->oformat->flags &amp; AVFMT_GLOBALHEADER)
  
      {
  
          _video->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
      }
  
  
  
      // Open file
  
      avio_open(&amp;_avFmtCtx->pb, path.c_str(), AVIO_FLAG_WRITE);
  
      avformat_write_header(_avFmtCtx, nullptr);
  
  
  
      AVFrame *_frame = av_frame_alloc();
  
      _frame->format = _video->codec->pix_fmt;
  
      _frame->width = _video->codec->width;
  
      _frame->height = _video->codec->height;
  
      _frame->pts = 0;
  
  
  
      /* the image can be allocated by any means and av_image_alloc() is  *
  
       * just the most convenient way if av_malloc() is to be used        */
  
      av_image_alloc(_frame->data, _frame->linesize, _video->codec->width, _video->codec->height, _video->codec->pix_fmt, 32);
  
  
  
      avcodec_open2(_video->codec, codec, nullptr);
  
  
  
      SwsContext *_swsCtx = sws_getContext(width, height,
  
          AV_PIX_FMT_BGRA,
  
          width, height,
  
          AV_PIX_FMT_YUV420P,
  
          0, 0, 0, 0);
  
  
  
      AVPacket packet;
  
      for (int i = 0; i &lt; 25; i++)
  
      {
  
          AddFrame(packet, _video->codec, _avFmtCtx, _frame, i);
  
      }
  
  
  
      /* get the delayed frames */
  
      int got_output = 1;
  
      while (got_output)
  
      {
  
          // Initialize a packet and clear data as it will be allocated by the encoder
  
          AVPacket pkt;
  
          av_init_packet(&amp;pkt);
  
          pkt.data = nullptr;
  
          pkt.size = 0;
  
  
  
          avcodec_encode_video2(_video->codec, &amp;pkt, nullptr, &amp;got_output);
  
  
  
          if (got_output)
  
          {
  
              av_interleaved_write_frame(_avFmtCtx, &amp;pkt);
  
              av_packet_unref(&amp;pkt);
  
          }
  
      }
  
  
  
      av_write_trailer(_avFmtCtx);
  
      avio_close(_avFmtCtx->pb);
  
      sws_freeContext(_swsCtx);
  
      av_freep(&amp;_frame->data);
  
      av_frame_free(&amp;_frame);
  
      avcodec_close(_video->codec);
  
      avformat_free_context(_avFmtCtx);
  
  }

• audiodsp/x86 : clear the high bits of the order parameter on 64bit

  9 août 2016, par Anton Khirnov

  audiodsp/x86 : clear the high bits of the order parameter on 64bit
  Also change shl to add, since it can be faster on some CPUs.
  CC : libav-stable@libav.org
  

  • [DBH] libavcodec/x86/audiodsp.asm