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• How do I download a list mpd with ffmpeg

  13 mai 2016, par Don Donllei

  I did download the video from a site that used M3U8 but he moved to mpd and do not know how do I download it.

  <mpd type="static" minbuffertime="PT1S" mediapresentationduration="PT0H1M56.320S" profiles="urn:mpeg:dash:profile:full:2011"><programinformation moreinformationurl="http://gpac.sourceforge.net"></programinformation><period start="PT0S" duration="PT0H1M56.320S"><adaptationset segmentalignment="true" maxwidth="1920" maxheight="1080" maxframerate="25" par="16:9"><contentcomponent contenttype="video"></contentcomponent><contentcomponent contenttype="audio"></contentcomponent><segmenttemplate timescale="1000" duration="9693" media="$RepresentationID$/Y7aRjDxbh_$Number$.m4s" startnumber="1" initialization="$RepresentationID$/Y7aRjDxbh_init.mp4"></segmenttemplate><representation mimetype="video/mp4" codecs="avc3.64000d,mp4a.40.2" width="320" height="240" framerate="25" sar="4:3" audiosamplingrate="44100" startwithsap="1" bandwidth="400000">
  
      </representation><representation mimetype="video/mp4" codecs="avc3.64001e,mp4a.40.2" width="720" height="480" framerate="25" sar="32:27" audiosamplingrate="44100" startwithsap="1" bandwidth="900000">
  
    </representation><representation mimetype="video/mp4" codecs="avc3.64001f,mp4a.40.2" width="960" height="720" framerate="25" sar="4:3" audiosamplingrate="44100" startwithsap="1" bandwidth="1500000">
  
     </representation><representation mimetype="video/mp4" codecs="avc3.640028,mp4a.40.2" width="1920" height="1080" framerate="25" sar="1:1" audiosamplingrate="44100" startwithsap="1" bandwidth="3500000">
  
     </representation><representation mimetype="video/mp4" codecs="avc3.640028,mp4a.40.2" width="2730" height="1440" framerate="25" sar="1:1" audiosamplingrate="44100" startwithsap="1" bandwidth="10000000">
  
     </representation><representation mimetype="video/mp4" codecs="avc3.640028,mp4a.40.2" width="4096" height="2160" framerate="25" sar="1:1" audiosamplingrate="44100" startwithsap="1" bandwidth="20000000">
  
     </representation></adaptationset></period></mpd>

• Create video using ffmpeg

  18 avril 2016, par Sagar

  I have 100 images(PNG) and I want to create a video using these images. I am using the ffmpeg library for this. Using command line I can create video easily. But how do I do it through coding ?

  Any help will be appreciated.

  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
  
  
  
  
  
  #include 
  
  #include 
  
  #include 
  
  
  
  #ifdef HAVE_AV_CONFIG_H
  
  #undef HAVE_AV_CONFIG_H
  
  #endif
  
  
  
  extern "C"
  
  {
  
  #include "libavutil/imgutils.h"
  
  #include "libavutil/opt.h"
  
  #include "libavcodec/avcodec.h"
  
  #include "libavutil/mathematics.h"
  
  #include "libavutil/samplefmt.h"
  
  }
  
  
  
  #define INBUF_SIZE 4096
  
  #define AUDIO_INBUF_SIZE 20480
  
  #define AUDIO_REFILL_THRESH 4096
  
  
  
  
  
  
  
  
  
  static void video_encode_example(const char *filename, int codec_id)
  
  {
  
     AVCodec *codec;
  
     AVCodecContext *c= NULL;
  
     int i, out_size, size, x, y, outbuf_size;
  
     FILE *f;
  
     AVFrame *picture;
  
     uint8_t *outbuf;
  
     int nrOfFramesPerSecond  =25;
  
     int nrOfSeconds =1;
  
  
  
  
  
     printf("Video encoding\n");
  
  
  
  //    find the mpeg1 video encoder
  
     codec = avcodec_find_encoder((CodecID) codec_id);
  
     if (!codec) {
  
         fprintf(stderr, "codec not found\n");
  
         exit(1);
  
     }
  
  
  
     c = avcodec_alloc_context3(codec);
  
     picture= avcodec_alloc_frame();
  
  
  
  //    put sample parameters
  
     c->bit_rate = 400000;
  
  //    resolution must be a multiple of two
  
     c->width = 352;
  
     c->height = 288;
  
  //    frames per second
  
     c->time_base= (AVRational){1,25};
  
     c->gop_size = 10;  //emit one intra frame every ten frames
  
     c->max_b_frames=1;
  
     c->pix_fmt = PIX_FMT_YUV420P;
  
  
  
     if(codec_id == CODEC_ID_H264)
  
         av_opt_set(c->priv_data, "preset", "slow", 0);
  
  
  
  //    open it
  
     if (avcodec_open2(c, codec, NULL) < 0) {
  
         fprintf(stderr, "could not open codec\n");
  
         exit(1);
  
     }
  
  
  
     f = fopen(filename, "wb");
  
     if (!f) {
  
         fprintf(stderr, "could not open %s\n", filename);
  
         exit(1);
  
     }
  
  
  
  //    alloc image and output buffer
  
     outbuf_size = 100000;
  
     outbuf = (uint8_t*) malloc(outbuf_size);
  
  
  
  //    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(picture->data, picture->linesize,
  
                    c->width, c->height, c->pix_fmt, 1);
  
  
  
  //    encode 1 second of video
  
     int nrOfFramesTotal = nrOfFramesPerSecond * nrOfSeconds;
  
  
  
  //    encode 1 second of video
  
     for(i=0;i < nrOfFramesTotal; i++) {
  
         fflush(stdout);
  
  //        prepare a dummy image
  
  
  
         for(y=0;yheight;y++) {
  
             for(x=0;xwidth;x++) {
  
                 picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
  
             }
  
         }
  
  
  
  //        Cb and Cr
  
         for(y=0;yheight/2;y++) {
  
             for(x=0;xwidth/2;x++) {
  
                 picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
  
                 picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
  
             }
  
         }
  
  
  
  //        encode the image
  
         out_size = avcodec_encode_video(c, outbuf, outbuf_size, picture);
  
         printf("encoding frame %3d (size=%5d)\n", i, out_size);
  
         fwrite(outbuf, 1, out_size, f);
  
     }
  
  
  
  //    get the delayed frames
  
     for(; out_size; i++) {
  
         fflush(stdout);
  
  
  
         out_size = avcodec_encode_video(c, outbuf, outbuf_size, NULL);
  
         printf("write frame %3d (size=%5d)\n", i, out_size);
  
         fwrite(outbuf, 1, out_size, f);
  
     }
  
  
  
  //    add sequence end code to have a real mpeg file
  
     outbuf[0] = 0x00;
  
     outbuf[1] = 0x00;
  
     outbuf[2] = 0x01;
  
     outbuf[3] = 0xb7;
  
     fwrite(outbuf, 1, 4, f);
  
     fclose(f);
  
     free(outbuf);
  
  
  
     avcodec_close(c);
  
  //   av_free(c);
  
  //   av_free(picture->data[0]);
  
  //   av_free(picture);
  
     printf("\n");
  
  }
  
  
  
  int main(int argc, char **argv)
  
  {
  
     const char *filename;
  
  
  
  
  
     avcodec_register_all();
  
  
  
     if (argc <= 1) {
  
  
  
         video_encode_example("/home/radix/Desktop/OpenCV/FFMPEG_Output/op89.png", AV_CODEC_ID_H264);
  
     } else {
  
         filename = argv[1];
  
     }
  
  
  
  
  
     return 0;
  
  }

  • On searching everytime i m getting code similar to this.But i don’t understood hot to use it for creating video from images.

• ffmpeg : avcodec_open2 returns invalid argument

  12 mai 2016, par roari

  i’m reusing the sample code from the developer 64bit release of ffmpeg in my application to encode a video :

  AVCodec* pCodec_{nullptr};
  
  AVCodecContext* pContext_{nullptr};
  
  
  
  avcodec_register_all();
  
  pCodec_ = avcodec_find_encoder(AV_CODEC_ID_MPEG2VIDEO);
  
  if (!pCodec_) {}
  
  
  
  pContext_ = avcodec_alloc_context3(pCodec_);
  
  if (!pContext_) {}
  
  
  
  pContext_->bit_rate = 400000;
  
  pContext_->width = size.width();
  
  pContext_->height = size.height();
  
  
  
  pContext_->time_base.den = 1;
  
  pContext_->time_base.num = fps;
  
  
  
  pContext_->gop_size = 10;
  
  pContext_->max_b_frames = 1;
  
  pContext_->pix_fmt = AV_PIX_FMT_BGR0;
  
  
  
  if (codec_id == AV_CODEC_ID_H264) {
  
      av_opt_set(pContext_->priv_data, "preset", "slow", 0);
  
  }
  
  
  
  int err = avcodec_open2(pContext_, pCodec_, nullptr);
  
  if (err < 0) {}

  AVCodec* and AVCodecContext* look like they are allocated correctly. avcodec_open2 then returns invalid argument (-22).

  I use : Windows 10 64, VS2013 Compiler, Qt Creator IDE, ffmpeg(2016-05-12) 64bit.

  The sample i took the code from is "decoding_encoding.c".

  Any ideas ?