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• FFmpeg make mpeg2 ts without discontinuity

  31 mai 2012, par user1427162

  I have many MOV files recorded with iPhone and I want to convert them to mpeg2 TS. I want to use them for live video streaming with HTTP Live Streaming protocol.

  I set my iPhone to continiously send MOV files to server. Every video clip is 5 seconds long. I want to make mpeg2 TS out of them and add their urls to m3u8 playlist.
  I managed to do all of that, but when I try to play the stream VLC player plays only first two files in playlist, and last file in playlist at that moment.
  I searched the internet and I think this has something to do with discontinuity.

  Is there any way to convert multiple MOV files into multiple mpeg2 TS segments without discontinuity ?

  Or maybe I'm doing something else wrong ?
  Here is my ffmpeg command :

  ffmpeg.exe -i input,MOV -f mpegts output.ts

  and here is my m3u8 list :

  #EXTM3U
  
  #EXT-X-PLAYLIST-TYPE:EVENT
  
  #EXT-X-TARGETDURATION:10
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXTINF:10,
  
  fileSequence0.ts
  
  #EXTINF:10,
  
  fileSequence1.ts
  
  #EXTINF:10,
  
  fileSequence2.ts

  Thanks in advance

• FFMPEG encode klv data with video

  23 janvier 2021, par Reza Shahriari

  I am trying to encode KLV metadata (MISB 0601) with a regular video stream. I am using the ffmpeg examples and hove come up with this

  


  to start a klv stream :

  


  int Streamer::add_klv_stream(){
    this->klv_stream = avformat_new_stream(this->output_context, NULL);
    this->klv_stream->codec->codec_type = AVMEDIA_TYPE_DATA;
    this->klv_stream->codec->codec_id = AV_CODEC_ID_SMPTE_KLV;
    this->klv_stream->codec->codec_tag = 1096174667; //some magic number?
    this->klv_stream->time_base = AVRational{ 1, 30 };
    this->klv_stream->id = this->output_context->nb_streams - 1;
}


  


  to add a klv data packet

  


  int Streamer::addKlv(uint8_t * some_array) {
    AVPacket pkt;
    av_init_packet(&pkt);
    pkt.size = 10;
    pkt.data = some_array;//(uint8_t*)GetKlv(pkt.size);
    auto res = write_frame(this->output_context, &this->video_stream.st->time_base, this->klv_stream, &pkt);
    //ret = write_frame(this->output_context, &c->time_base, this->video_stream.st, &pkt);
    free(pkt.data);

    return res;
}


  


  However, I get a BAD ACCESSS error in write_frame (specifically the av_interleaved_write_frame call)

  


  int Streamer::write_frame(AVFormatContext *fmt_ctx, const AVRational *time_base, AVStream *st, AVPacket *pkt)
{
    /* rescale output packet timestamp values from codec to stream timebase */
    av_packet_rescale_ts(pkt, *time_base, st->time_base);
    pkt->stream_index = st->index;
    /* Write the compressed frame to the media file. */
    //log_packet(fmt_ctx, pkt);
    return av_interleaved_write_frame(fmt_ctx, pkt); //error is here
}


  


  If anyone knows how to mux klv data and video it would be much appreciated.

  


  Thanks in advance.

  


• How to estimate bandwidth / speed requirements for real-time streaming video ?

  19 juin 2016, par Vivek Seth

  For a project I’m working on, I’m trying to stream video to an iPhone through its headphone jack. My estimated bitrate is about 200kbps (If i’m wrong about this, please ignore that).

  I’d like to squeeze as much performance out of this bitrate as possible and sound is not important for me, only video. My understanding is that to stream a a real-time video I will need to encode it with some codec on-the-fly and send compressed frames to the iPhone for it to decode and render. Based on my research, it seems that H.265 is one of the most space efficient codecs available so i’m considering using that.

  Assuming my basic understanding of live streaming is correct, how would I estimate the FPS I could achieve for a given resolution using the H.265 codec ?

  The best solution I can think of it to take a video file, encode it with H.265 and trim it to 1 minute of length to see how large the file is. The issue I see with this approach is that I think my calculations would include some overhead from the video container format (AVI, MKV, etc) and from the audio channels that I don’t care about.