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• How to use ffmpeg to encode mp4 to mov

  19 avril 2017, par user1526912

  I trying to use ffmpeg to encode a video for the first time. Can anyone tell me the exact command to encode a video in the following format :

  Music Video HD Source Profile

  ● Apple ProRes 422 (HQ)
  ● VBR expected at 220 Mbps
  ● HD encoded dimensions accepted to support square pixel aspect ratios (PASP) :
  Encoded PASP Converted to ProRes From
  1920 x 1080 1:1 HDCAM SR, D5, ATSC
  1280 x 720 1:1 ATSC progressive

  ● HD encoded dimensions accepted to support non-square pixel aspect ratios (this allows you to send HD video in the native dimensions of your best original source, for example in HD broadcast dimensions*) :

  Encoded PASP Converted to ProRes From
  1440 x 1080 1:1.33333 XDCAM-HD, HDCAM
  1280 x 1080 1:1.5 DVCProHD interlaced
  960 x 720 1:1.33333 DVCProHD progressive

  Native frame rate of original source :

  ● 29.97 interlaced frames per second for video sourced
  ● 24 or 25 progressive frames per second for film sourced
  ● 23.976 progressive frames for inverse telecine sourced from film
  ● Telecine materials will not be accepted

  ● HD source may be delivered matted : letterbox, pillarbox, or windowbox.

  Music Video Audio Source Profile

  Stereo
  ● MPEG-1 layer II stereo
  ● 384 kpbs
  ● 48Khz
  ● Included in the same file as the delivered video

• adaptives links for mpeg dash on wowza server not working, status error 404 Not Found

  12 août 2015, par jobin

  adaptives links for mpeg dash on wowza server not working with me, the following are the steps that I used to publish video on wowza :

  1. I install and configure Wowza server, and I tested it and it is working fine.

  2. Transcode this video using ffmepg (I bring these command from wowza documentation) :

     set inputFile="C :\video\sintel.mp4"
     set outputFile="C :\video\sintel"

     ffmpeg -y -i %inputFile% -s 320x180 -y -strict experimental -acodec aac -ab 64k -ac 2 -ar 48000 -vcodec libx264 -vprofile baseline -level 30 -g 48 -b 200000 -threads 64 %outputFile%_320p.mp4
     ffmpeg -y -i %inputFile% -s 640x360 -y -strict experimental -acodec aac -ab 128k -ac 2 -ar 48000 -vcodec libx264 -vprofile baseline -level 30 -g 48 -b 520000 -threads 64 %outputFile%_640p.mp4
     ffmpeg -y -i %inputFile% -s 320x180 -y -strict experimental -acodec aac -ab 64k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 270000 -threads 64 %outputFile%_400p.mp4
     ffmpeg -y -i %inputFile% -s 420x270 -y -strict experimental -acodec aac -ab 64k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 570000 -threads 64 %outputFile%_700p.mp4
     ffmpeg -y -i %inputFile% -s 720x406 -y -strict experimental -acodec aac -ab 128k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 1000000 -threads 64 %outputFile%_1100p.mp4
     ffmpeg -y -i %inputFile% -s 1024x576 -y -strict experimental -acodec aac -ab 128k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 1200000 -threads 64 %outputFile%_1300p.mp4
     ffmpeg -y -i %inputFile% -s 1080x608 -y -strict experimental -acodec aac -ab 128k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 1400000 -threads 64 %outputFile%_1500p.mp4

  3. I test the files and all of them workig fine then I moved these files to wowza content folder and create the smil file as following :

  

  <?xml version="1.0" encoding="UTF-8"?>
  
  <smil title="sintel">
  
    
  
      <switch>
  
        <video width="320" height="180" src="sintel_320p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
        <video width="640" height="360" src="sintel_640p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
        <video width="320" height="180" src="sintel_400p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
        <video width="420" height="270" src="sintel_700p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
        <video width="720" height="406" src="sintel_1100p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
        <video width="1024" height="576" src="sintel_1300p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
        <video width="1080" height="608" src="sintel_1500p.mp4" systemlanguage="eng">
  
          
  
          
  
        </video>
  
      </switch>
  
    
  
  </smil>

  4. I use the mpd file (http://191.237.26.137:1935/vod/smil:sintel.smil/manifest.mpd) with http://www.jwplayer.com/innovation/roadmap/mpeg-dash/

  Result : the video work for first few seconds the stop

  

• FFmpeg muxing to avi

  2 septembre 2015, par Uncia

  sI have program, that succefully shows h264 stream using SDL : I’m getting h264 frame, decode it using ffmpeg and draw using SDL.
  Also I can write frames to file (using fwrite) and play this file through ffplay.

  But I want to mux data to the avi and face some problems in av_write_frame.

  Here is my code :

  ...
  
  /*Initializing format context - outFormatContext is the member of my class*/
  
  AVOutputFormat *outFormat;
  
  outFormat = av_guess_format(NULL,"out.avi",NULL);
  
  outFormat->video_codec = AV_CODEC_ID_H264;
  
  outFormat->audio_codec = AV_CODEC_ID_NONE;
  
  avformat_alloc_output_context2(&outFormatContext, outFormat, NULL, "out.avi");
  
  AVCodec *outCodec;
  
  AVStream *outStream = add_stream(outFormatContext, &outCodec, outFormatContext->oformat->video_codec);
  
  avcodec_open2(outStream->codec, outCodec, NULL);
  
  av_dump_format(outFormatContext, 0, "out.avi", 1);
  
  if (avio_open(&outFormatContext->pb, "out.avi", AVIO_FLAG_WRITE) < 0) 
  
      throw Exception("Couldn't open file");
  
  if (avformat_write_header(outFormatContext, NULL) < 0)
  
      throw Exception("Couldn't write to file");
  
   //I don't have exceptions here - so there is 6KB header in out.avi.
  
   ...
  
  
  
  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)) 
  
      throw("Could not find encoder");
  
  st = avformat_new_stream(oc, *codec);
  
  if (!st) 
  
      throw ("Could not allocate stream");
  
  st->id = oc->nb_streams-1;
  
  c = st->codec;
  
  c->bit_rate = 400000;
  
  /* Resolution must be a multiple of two. */
  
  c->width    = 1920;
  
  c->height   = 1080;
  
  c->pix_fmt  = PIX_FMT_YUV420P;
  
  c->flags = 0;
  
  c->time_base.num = 1;
  
  c->time_base.den = 25;
  
  c->gop_size      = 12; /* emit one intra frame every twelve frames at most */
  
  return st;
  
  }
  
  ...
  
  /* Part of decoding loop. There is AVPacket packet - h264 packet;
  
  int ret = av_write_frame(outFormatContext, &packet); //it return -22 code - Invadlid argument;
  
  if (avcodec_decode_video2(pCodecCtx, pFrame, &frameDecoded, &packet) < 0) 
  
      return;
  
  if (frameDecoded)
  
  {
  
     //SDL stuff
  
  }

  Also i tried to use avcodec_encode_video2 (encode pFrame back to the H264) next to the SDL stuff but encoding is not working - i’ve got empty packets :( It is the second problem.

  Using av_interleaved_write_frame causes acces violation.

  Code of the muxing part i copied from ffmpeg muxing example (https://www.ffmpeg.org/doxygen/2.1/doc_2examples_2muxing_8c-example.html)