Recherche avancée

Sur d’autres sites (4868)

• Trying to cancel execution and delete file using ffmpeg C API

  6 mars 2020, par Vuwox

  The code below is a class that handle the conversion of multiples images, through add_frame() method, into a GIF with encode(). It also use a filter to generate and apply the palette. The usage is like this :

  Code call example

  std::unique_ptr gif_obj = nullptr;
  
  try
  
  {
  
      gif_obj = std::make_unique({1000,1000}, 12, "C:/out.gif",
  
                "format=pix_fmts=rgb24,split [a][b];[a]palettegen[p];[b][p]paletteuse");
  
  
  
      // Example: a simple vector of images (usually process internally)
  
      for(auto img : image_vector)
  
           gif_obj->add_frame(img);
  
  
  
      // Once all frame were added, encode the final GIF with the filter applied.
  
      gif_obj->encode();
  
  }
  
  catch(const std::exception& e)
  
  {
  
      // An error occured! We must close FFMPEG properly and delete the created file.
  
      gif_obj->cancel();
  
  }

  I have the following issue. If the code for any reason throw an exception, I call ffmpeg->cancel() and it supposes to delete the GIF file on disk. But this is never working, I assume there is a lock on the file or something like that. So here are my question :

  What is the proper way to close/free ffmpeg object in order to remove the file afterward ?

  ---

  Full class code below

  Header

  // C++ Standard includes    
  
  #include <memory>
  
  #include <string>
  
  #include <vector>
  
  
  
  
  
  // 3rd Party incldues
  
  #ifdef __cplusplus
  
  extern "C" {
  
  #include "libavformat/avformat.h"
  
  #include "libavfilter/avfilter.h"
  
  #include "libavutil/opt.h"
  
  #include "libavfilter/buffersrc.h"
  
  #include "libavfilter/buffersink.h"
  
  #include "libswscale/swscale.h"
  
  #include "libavutil/imgutils.h"
  
  }
  
  #endif
  
  
  
  #define FFMPEG_MSG_LEN 2000
  
  
  
  namespace px
  
  {
  
      namespace GIF
  
      {
  
          class FFMPEG
  
          {
  
          public:
  
              FFMPEG(const px::Point2D<int>&amp; dim,
  
                     const int framerate,
  
                     const std::string&amp; filename,
  
                     const std::string&amp; filter_cmd);
  
  
  
              ~FFMPEG();
  
  
  
              void add_frame(pxImage * const img);
  
              void encode();
  
              void cancel();
  
  
  
          private:
  
  
  
              void init_filters();            // Init everything that needed to filter the input frame.
  
              void init_muxer();              // The muxer that creates the output file.
  
              void muxing_one_frame(AVFrame* frame);
  
              void release();
  
  
  
              int _ret = 0;                   // status code from FFMPEG.
  
              char _err_msg[FFMPEG_MSG_LEN];  // Error message buffer.
  
  
  
  
  
              int m_width = 0;                // The width that all futur images must have to be accepted.
  
              int m_height = 0;               // The height that all futur images must have to be accepted.
  
  
  
              int m_framerate = 0;            // GIF Framerate.
  
              std::string m_filename = "";    // The GIF filename (on cache?)
  
              std::string m_filter_desc = ""; // The FFMPEG filter to apply over the frames.
  
  
  
              bool as_frame = false;
  
  
  
              AVFrame* picture_rgb24 = nullptr;           // Temporary frame that will hold the pxImage in an RGB24 format (NOTE: TOP-LEFT origin)
  
  
  
              AVFormatContext* ofmt_ctx = nullptr;        // ouput format context associated to the 
  
              AVCodecContext* o_codec_ctx = nullptr;      // output codec for the GIF
  
  
  
              AVFilterGraph* filter_graph = nullptr;      // filter graph associate with the string we want to execute
  
              AVFilterContext* buffersrc_ctx = nullptr;   // The buffer that will store all the frames in one place for the palette generation.
  
              AVFilterContext* buffersink_ctx = nullptr;  // The buffer that will store the result afterward (once the palette are used).
  
  
  
              int64_t m_pts_increment = 0;
  
          };
  
      };
  
  };
  
  </int></vector></string></memory>

  ctor

  px::GIF::FFMPEG::FFMPEG(const px::Point2D<int>&amp; dim,
  
                          const int framerate,
  
                          const std::string&amp; filename,
  
                          const std::string&amp; filter_cmd) :
  
      m_width(dim.x()),
  
      m_height(dim.y()),
  
      m_framerate(framerate),
  
      m_filename(filename),
  
      m_filter_desc(filter_cmd)
  
  {
  
  #if !_DEBUG
  
      av_log_set_level(AV_LOG_QUIET); // Set the FFMPEG log to quiet to avoid too much logs.
  
  #endif
  
  
  
      // Allocate the temporary buffer that hold the ffmpeg image (pxImage to AVFrame conversion).
  
      picture_rgb24 = av_frame_alloc();
  
      picture_rgb24->pts = 0;
  
      picture_rgb24->data[0] = NULL;
  
      picture_rgb24->linesize[0] = -1;
  
      picture_rgb24->format = AV_PIX_FMT_RGB24;
  
      picture_rgb24->height = m_height;
  
      picture_rgb24->width = m_width; 
  
  
  
      if ((_ret = av_image_alloc(picture_rgb24->data, picture_rgb24->linesize, m_width, m_height, (AVPixelFormat)picture_rgb24->format, 24)) &lt; 0)
  
          throw px::GIF::Error("Failed to allocate the AVFrame for pxImage conversion with error: " +
  
                               std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)),
  
                               "GIF::FFMPEG CTOR");   
  
  
  
      //printf("allocated picture of size %d, linesize %d %d %d %d\n", _ret, picture_rgb24->linesize[0], picture_rgb24->linesize[1], picture_rgb24->linesize[2], picture_rgb24->linesize[3]);
  
  
  
      init_muxer();   // Prepare the GIF encoder (open it on disk).
  
      init_filters(); // Prepare the filter that will be applied over the frame.
  
  
  
      // Instead of hardcoder {1,100} which is the GIF tbn, we collect it from its stream.
  
      // This will avoid future problem if the codec change in ffmpeg.
  
      if (ofmt_ctx &amp;&amp; ofmt_ctx->nb_streams > 0)
  
          m_pts_increment = av_rescale_q(1, { 1, m_framerate }, ofmt_ctx->streams[0]->time_base);
  
      else
  
          m_pts_increment = av_rescale_q(1, { 1, m_framerate }, { 1, 100 });
  
  }
  
  </int>

  FFMPEG Initialization (Filter and muxer)

  void px::GIF::FFMPEG::init_filters()
  
  {
  
      const AVFilter* buffersrc = avfilter_get_by_name("buffer");
  
      const AVFilter* buffersink = avfilter_get_by_name("buffersink");
  
  
  
      AVRational time_base = { 1, m_framerate };
  
      AVRational aspect_pixel = { 1, 1 };
  
  
  
      AVFilterInOut* inputs = avfilter_inout_alloc();
  
      AVFilterInOut* outputs = avfilter_inout_alloc();
  
  
  
      filter_graph = avfilter_graph_alloc();
  
  
  
      try
  
      {
  
          if (!outputs || !inputs || !filter_graph)
  
              throw px::GIF::Error("Failed to 'init_filters' could not allocated the graph/filters.", "GIF::FFMPEG init_filters");
  
  
  
          char args[512];
  
          snprintf(args, sizeof(args),
  
                   "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
  
                   m_width, m_height,
  
                   picture_rgb24->format,
  
                   time_base.num, time_base.den,
  
                   aspect_pixel.num, aspect_pixel.den);
  
  
  
          if (avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in", args, nullptr, filter_graph) < 0)
  
              throw px::GIF::Error("Failed to create the 'source buffer' in init_filer method.", "GIF::FFMPEG init_filters");
  
  
  
  
  
          if (avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out", nullptr, nullptr, filter_graph) < 0)
  
              throw px::GIF::Error("Failed to create the 'sink buffer' in init_filer method.", "GIF::FFMPEG init_filters");
  
  
  
          // GIF has possible output of PAL8.
  
          enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_PAL8, AV_PIX_FMT_NONE };
  
  
  
          if (av_opt_set_int_list(buffersink_ctx, "pix_fmts", pix_fmts, AV_PIX_FMT_NONE, AV_OPT_SEARCH_CHILDREN) < 0)
  
              throw px::GIF::Error("Failed to set the output pixel format.", "GIF::FFMPEG init_filters");
  
  
  
          outputs->name = av_strdup("in");
  
          outputs->filter_ctx = buffersrc_ctx;
  
          outputs->pad_idx = 0;
  
          outputs->next = nullptr;
  
  
  
          inputs->name = av_strdup("out");
  
          inputs->filter_ctx = buffersink_ctx;
  
          inputs->pad_idx = 0;
  
          inputs->next = nullptr;
  
  
  
          // GIF has possible output of PAL8. 
  
          if (avfilter_graph_parse_ptr(filter_graph, m_filter_desc.c_str(), &inputs, &outputs, nullptr) < 0)
  
              throw px::GIF::Error("Failed to parse the filter graph (bad string!).", "GIF::FFMPEG init_filters");
  
  
  
          if (avfilter_graph_config(filter_graph, nullptr) < 0)
  
              throw px::GIF::Error("Failed to configure the filter graph (bad string!).", "GIF::FFMPEG init_filters");
  
  
  
          avfilter_inout_free(&inputs);
  
          avfilter_inout_free(&outputs);
  
      }
  
      catch (const std::exception& e)
  
      {
  
          // Catch exception to delete element.
  
          avfilter_inout_free(&inputs);
  
          avfilter_inout_free(&outputs);
  
          throw e; // re-throuw
  
      }
  
  }
  
  
  
  
  
  void px::GIF::FFMPEG::init_muxer()
  
  {
  
      AVOutputFormat* o_fmt = av_guess_format("gif", m_filename.c_str(), "video/gif");
  
  
  
      if ((_ret = avformat_alloc_output_context2(&ofmt_ctx, o_fmt, "gif", m_filename.c_str())) < 0)
  
          throw px::GIF::Error(std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)) + " allocate output format.", "GIF::FFMPEG init_muxer");
  
  
  
      AVCodec* codec = avcodec_find_encoder(AV_CODEC_ID_GIF);
  
      if (!codec) throw px::GIF::Error("Could to find the 'GIF' codec.", "GIF::FFMPEG init_muxer");
  
  
  
  #if 0
  
      const AVPixelFormat* p = codec->pix_fmts;
  
      while (p != NULL && *p != AV_PIX_FMT_NONE) {
  
          printf("supported pix fmt: %s\n", av_get_pix_fmt_name(*p));
  
          ++p;
  
      }
  
  #endif
  
  
  
      AVStream* stream = avformat_new_stream(ofmt_ctx, codec);
  
  
  
      AVCodecParameters* codec_paramters = stream->codecpar;
  
      codec_paramters->codec_tag = 0;
  
      codec_paramters->codec_id = codec->id;
  
      codec_paramters->codec_type = AVMEDIA_TYPE_VIDEO;
  
      codec_paramters->width = m_width;
  
      codec_paramters->height = m_height;
  
      codec_paramters->format = AV_PIX_FMT_PAL8;
  
  
  
      o_codec_ctx = avcodec_alloc_context3(codec);
  
      avcodec_parameters_to_context(o_codec_ctx, codec_paramters);
  
  
  
      o_codec_ctx->time_base = { 1, m_framerate };
  
  
  
      if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
  
          o_codec_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
  
  
  
      if ((_ret = avcodec_open2(o_codec_ctx, codec, NULL)) < 0)
  
          throw px::GIF::Error(std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)) + " open output codec.", "GIF::FFMPEG init_muxer");
  
  
  
      if ((_ret = avio_open(&ofmt_ctx->pb, m_filename.c_str(), AVIO_FLAG_WRITE)) < 0)
  
          throw px::GIF::Error(std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)) + " avio open error.", "GIF::FFMPEG init_muxer");
  
  
  
      if ((_ret = avformat_write_header(ofmt_ctx, NULL)) < 0)
  
          throw px::GIF::Error(std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)) + " write GIF header", "GIF::FFMPEG init_muxer");
  
  
  
  #if _DEBUG
  
      // This print the stream/output format.
  
      av_dump_format(ofmt_ctx, -1, m_filename.c_str(), 1);
  
  #endif
  
  }

  Add frame (usually in a loop)

  void px::GIF::FFMPEG::add_frame(pxImage * const img)
  
  {
  
      if (img->getImageType() != PXT_BYTE || img->getNChannels() != 4)
  
          throw px::GIF::Error("Failed to 'add_frame' since image is not PXT_BYTE and 4-channels.", "GIF::FFMPEG add_frame");
  
  
  
      if (img->getWidth() != m_width || img->getHeight() != m_height)
  
          throw px::GIF::Error("Failed to 'add_frame' since the size is not same to other inputs.", "GIF::FFMPEG add_frame");
  
  
  
      const int pitch = picture_rgb24->linesize[0];
  
      auto px_ptr = getImageAccessor(img);
  
  
  
      for (int y = 0; y < m_height; y++)
  
      {
  
          const int px_row = img->getOrigin() == ORIGIN_BOT_LEFT ? m_height - y - 1 : y;
  
          for (int x = 0; x < m_width; x++)
  
          {
  
              const int idx = y * pitch + 3 * x;
  
              picture_rgb24->data[0][idx] = px_ptr[px_row][x].ch[PX_RE];
  
              picture_rgb24->data[0][idx + 1] = px_ptr[px_row][x].ch[PX_GR];
  
              picture_rgb24->data[0][idx + 2] = px_ptr[px_row][x].ch[PX_BL];
  
          }
  
      }
  
  
  
      // palettegen need a whole stream, just add frame to buffer.
  
      if ((_ret = av_buffersrc_add_frame_flags(buffersrc_ctx, picture_rgb24, AV_BUFFERSRC_FLAG_KEEP_REF)) < 0)
  
          throw px::GIF::Error("Failed to 'add_frame' to global buffer with error: " +
  
                               std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)),
  
                               "GIF::FFMPEG add_frame");
  
  
  
      // Increment the FPS of the picture for the next add-up to the buffer.      
  
      picture_rgb24->pts += m_pts_increment;
  
  
  
      as_frame = true;
  
  }    

  Encoder (final step)

  void px::GIF::FFMPEG::encode()
  
  {
  
      if (!as_frame)
  
          throw px::GIF::Error("Please 'add_frame' before running the Encoding().", "GIF::FFMPEG encode");
  
  
  
      // end of buffer
  
      if ((_ret = av_buffersrc_add_frame_flags(buffersrc_ctx, nullptr, AV_BUFFERSRC_FLAG_KEEP_REF)) < 0)
  
          throw px::GIF::Error("error add frame to buffer source: " + std::string(av_make_error_string(_err_msg, FFMPEG_MSG_LEN, _ret)), "GIF::FFMPEG encode");
  
  
  
      do {
  
          AVFrame* filter_frame = av_frame_alloc();
  
          _ret = av_buffersink_get_frame(buffersink_ctx, filter_frame);
  
          if (_ret == AVERROR(EAGAIN) || _ret == AVERROR_EOF) {
  
              av_frame_unref(filter_frame);
  
              break;
  
          }
  
  
  
          // write the filter frame to output file
  
          muxing_one_frame(filter_frame);
  
  
  
          av_frame_unref(filter_frame);
  
      } while (_ret >= 0);
  
  
  
      av_write_trailer(ofmt_ctx);
  
  }
  
  
  
  void px::GIF::FFMPEG::muxing_one_frame(AVFrame* frame)
  
  {
  
      int ret = avcodec_send_frame(o_codec_ctx, frame);
  
      AVPacket *pkt = av_packet_alloc();
  
      av_init_packet(pkt);
  
  
  
      while (ret >= 0) {
  
          ret = avcodec_receive_packet(o_codec_ctx, pkt);
  
          if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
  
              break;
  
          }
  
  
  
          av_write_frame(ofmt_ctx, pkt);
  
      }
  
      av_packet_unref(pkt);
  
  }

  DTOR, Release and Cancel

  px::GIF::FFMPEG::~FFMPEG()
  
  {
  
      release();
  
  }
  
  
  
  
  
  void px::GIF::FFMPEG::release()
  
  {
  
      // Muxer stuffs
  
      if (ofmt_ctx != nullptr) avformat_free_context(ofmt_ctx);
  
      if (o_codec_ctx != nullptr) avcodec_close(o_codec_ctx);
  
      if (o_codec_ctx != nullptr) avcodec_free_context(&o_codec_ctx);
  
  
  
      ofmt_ctx = nullptr;
  
      o_codec_ctx = nullptr;
  
  
  
      // Filter stuffs
  
      if (buffersrc_ctx != nullptr) avfilter_free(buffersrc_ctx);
  
      if (buffersink_ctx != nullptr) avfilter_free(buffersink_ctx);
  
      if (filter_graph != nullptr) avfilter_graph_free(&filter_graph);
  
  
  
      buffersrc_ctx = nullptr;
  
      buffersink_ctx = nullptr;
  
      filter_graph = nullptr;
  
  
  
      // Conversion image.
  
      if (picture_rgb24 != nullptr) av_frame_free(&picture_rgb24);
  
      picture_rgb24 = nullptr;
  
  }
  
  
  
  void px::GIF::FFMPEG::cancel()
  
  {
  
      // In-case of failure we must close ffmpeg and exit.
  
      av_write_trailer(ofmt_ctx);
  
  
  
      // Release and close all elements.
  
      release();
  
  
  
      // Delete the file on disk.
  
      if (remove(m_filename.c_str()) != 0)
  
          PX_LOG0(PX_LOGLEVEL_ERROR, "GIF::FFMPEG - On 'cancel' failed to remove the file.");
  
  }

• record rtsp stream to file(muxing)

  11 avril 2014, par user3521863

  AVFormatContext *g_oc = NULL;
  
  AVStream *g_in_audio_st, *g_in_video_st;
  
  AVStream *g_out_audio_st, *g_out_video_st;
  
  int audio_pts = 0, video_pts = 0, audio_dts = 0, video_dts = 0;
  
  int last_video_pts = 0;
  
  AVPacket outpkt, *av_pkt;
  
  
  
  // initialize video codec
  
  static void init_video_codec(AVFormatContext *context) {
  
      LOGI(1, "enter init_video_codec");
  
      AVFormatContext *in_format_ctx = NULL;
  
      AVCodecContext *avcodec_ctx = NULL;
  
      int fps = 0;
  
  
  
      if(context->streams[1]->r_frame_rate.num != AV_NOPTS_VALUE &&
  
              context->streams[1]->r_frame_rate.den != 0)
  
          fps = context->streams[1]->r_frame_rate.num / context->streams[1]->r_frame_rate.den;
  
      else
  
          fps = 25;
  
  
  
      g_out_video_st = avformat_new_stream(g_oc, context->streams[1]->codec->codec);
  
      LOGI(1, "video avformat_new_stream");
  
      if( g_out_video_st == NULL ) {
  
          LOGE(1, "Fail to Allocate Output Video Stream");
  
          return ;
  
      }
  
      else {
  
          LOGI(1, "Allocated Video Stream");
  
          if( avcodec_copy_context(g_out_video_st->codec, context->streams[1]->codec) != 0 ) {
  
              LOGE(1, "Failed to video Copy Context");
  
  
  
              return ;
  
          }
  
          else {
  
              LOGI(1, "Success to video Copy Context");
  
  // how to setting video stream parameter?
  
  
  
              g_out_video_st->sample_aspect_ratio.den = g_in_video_st->codec->sample_aspect_ratio.den;
  
              g_out_video_st->sample_aspect_ratio.num = g_in_video_st->codec->sample_aspect_ratio.num;
  
              g_out_video_st->codec->codec_id         = g_in_video_st->codec->codec->id;
  
              g_out_video_st->codec->time_base.num    = 1;
  
              g_out_video_st->codec->time_base.den    = fps * (g_in_video_st->codec->ticks_per_frame);
  
              g_out_video_st->time_base.num           = 1;
  
              g_out_video_st->time_base.den           = 1000;
  
              g_out_video_st->r_frame_rate.num        = fps;
  
              g_out_video_st->r_frame_rate.den        = 1;
  
              g_out_video_st->avg_frame_rate.den      = 1;
  
              g_out_video_st->avg_frame_rate.num      = fps;
  
              g_out_video_st->codec->width            = g_frame_width;
  
              g_out_video_st->codec->height           = g_frame_height;
  
              g_out_video_st->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
          }
  
      }
  
  
  
      LOGI(1, "end video init");
  
  }
  
  
  
  // initialize audio codec
  
  static void init_audio_codec(AVFormatContext *context) {
  
      LOGI(1, "enter init_audio_codec");
  
      AVFormatContext *in_format_ctx = NULL;
  
      AVCodecContext *avcodec_ctx = NULL;
  
  
  
      g_out_audio_st = avformat_new_stream(g_oc, context->streams[0]->codec->codec);
  
      LOGI(1, "audio avformat_new_stream");
  
      if( avcodec_copy_context(g_out_audio_st->codec, context->streams[0]->codec) != 0 ) {
  
          LOGE(1, "Failed to Copy audio Context");
  
  
  
          return ;
  
      }
  
      else {
  
          LOGI(1, "Success to Copy audio Context");
  
  // how to setting video stream parameter?
  
          g_out_audio_st->codec->codec_id         = g_in_audio_st->codec->codec_id;
  
          g_out_audio_st->codec->codec_tag        = 0;
  
          g_out_audio_st->pts                     = g_in_audio_st->pts;
  
          g_out_audio_st->time_base.num           = g_in_audio_st->time_base.num;
  
          g_out_audio_st->time_base.den           = g_in_audio_st->time_base.den;
  
          g_out_audio_st->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
      }
  
  
  
      LOGI(1, "end init audio");
  
  }
  
  
  
  // write video stream
  
  static void write_video_stream(AVPacket *pkt) {
  
      av_pkt = NULL;
  
      av_pkt = pkt;
  
  
  
      if( pkt == NULL || sizeof(*pkt) == 0 )
  
          return;
  
  
  
      av_rescale_q(av_pkt->pts, g_in_video_st->time_base, g_in_video_st->codec->time_base);
  
      av_rescale_q(av_pkt->dts, g_in_video_st->time_base, g_in_video_st->codec->time_base);
  
  
  
      av_init_packet(&outpkt);
  
  
  
      if( av_pkt->pts != AV_NOPTS_VALUE ) {
  
          if( last_video_pts == video_pts ) {
  
              video_pts++;
  
              last_video_pts = video_pts;
  
          }
  
          outpkt.pts = video_pts;
  
      }
  
      else {
  
          outpkt.pts = AV_NOPTS_VALUE;
  
      }
  
  
  
      if( av_pkt->dts == AV_NOPTS_VALUE )
  
          outpkt.dts = AV_NOPTS_VALUE;
  
      else
  
          outpkt.dts = video_pts;
  
  
  
      outpkt.data = av_pkt->data;
  
      outpkt.size = av_pkt->size;
  
      outpkt.stream_index = av_pkt->stream_index;
  
      outpkt.flags |= AV_PKT_FLAG_KEY;
  
      last_video_pts = video_pts;
  
  
  
      if(av_interleaved_write_frame(g_oc, &outpkt) < 0) {
  
  //  if(av_write_frame(g_oc, &outpkt) < 0) {
  
          LOGE(1, "Failed Video Write");
  
      }
  
      else {
  
          g_out_video_st->codec->frame_number++;
  
      }
  
  
  
      if( !&outpkt || sizeof(outpkt) == 0 )
  
          return;
  
      if( !av_pkt || sizeof(*av_pkt) == 0 )
  
          return;
  
  
  
      av_free_packet(&outpkt);
  
  }
  
  
  
  // write audio stream
  
  static void write_audio_stream(AVPacket *pkt) {
  
      av_pkt = NULL;
  
      av_pkt = pkt;
  
  
  
      if( pkt == NULL || sizeof(*pkt) == 0 )
  
              return;
  
  
  
      av_rescale_q(av_pkt->pts, g_in_audio_st->time_base, g_in_audio_st->codec->time_base);
  
      av_rescale_q(av_pkt->dts, g_in_audio_st->time_base, g_in_audio_st->codec->time_base);
  
  
  
      av_init_packet(&outpkt);
  
  
  
      if(av_pkt->pts != AV_NOPTS_VALUE)
  
          outpkt.pts = audio_pts;
  
      else
  
          outpkt.pts = AV_NOPTS_VALUE;
  
  
  
      if(av_pkt->dts == AV_NOPTS_VALUE)
  
          outpkt.dts = AV_NOPTS_VALUE;
  
      else {
  
          outpkt.dts = audio_pts;
  
  
  
          if( outpkt.pts >= outpkt.dts)
  
              outpkt.dts = outpkt.pts;
  
  
  
          if(outpkt.dts == audio_dts)
  
              outpkt.dts++;
  
  
  
          if(outpkt.pts < outpkt.dts) {
  
              outpkt.pts = outpkt.dts;
  
              audio_pts = outpkt.pts;
  
          }
  
  
  
          outpkt.data = av_pkt->data;
  
          outpkt.size = av_pkt->size;
  
          outpkt.stream_index = av_pkt->stream_index;
  
          outpkt.flags |= AV_PKT_FLAG_KEY;
  
          video_pts = audio_pts;
  
          audio_pts++;
  
  
  
          if( av_interleaved_write_frame(g_oc, &outpkt) < 0 ) {
  
  //      if( av_write_frame(g_oc, &outpkt) < 0 ) {
  
              LOGE(1, "Failed Audio Write");
  
          }
  
          else {
  
              g_out_audio_st->codec->frame_number++;
  
          }
  
  
  
          if( !&outpkt || sizeof(outpkt) == 0 )
  
              return;
  
          if( !av_pkt || sizeof(*av_pkt) == 0 )
  
              return;
  
  
  
          av_free_packet(&outpkt);
  
      }
  
  }

  here result : recorded file
  here full source : player.c

  I want to record rtsp stream to file on playing
  i try tested video and audio streams while changing the parameters
  but this result file does not match sync between video and audio
  i try search about ffmpeg but almost command run or video recording was only.
  please advice me.
  

• FFmpeg -segment with a lot of time codes

  24 février 2020, par Grenight

  I’m making program that splits videos for running parallel encodes.

  My problem is that with putting all segments into command like i can hit a limit of maximum characters in windows console. Approximately 600, while 1-2 hour movie can easily be 1000-2000 scenes.

  Is there a way to use .csv file for segment so i don’t need to put all time codes to command line ? Or is there another ways ?

  Here is example of command line that is used in program :
  timecodes is where all time codes passed.

  cmd = f'{self.FFMPEG} -i {video} -map_metadata 0 -an -f segment -segment_times {timecodes} -c copy -avoid_negative_ts 1 {self.temp_dir / "split" / "%04d.mkv"}