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• FFmpeg : generating H264 video in c++

  13 octobre 2015, par EZEROFIVE EMD

  Im using ffmpeg library in windows with vs2012 to convert a series of images into Mp4 with H264 encoding. Im new to FFMPEG.

  Below is my code. Everything went fine. Video is created.But i can play the video in vlc player only if i changed the extension to ".h264", also when i check for codec information it says "H264 - MPEG-4 AVC (part 10) (h264)". but when i checked the same for other mp4 videos which are downloaded from web. it says "H264 - MPEG-4" AVC (part 10) (avc1)". I dont understand where it went wrong. Also i searched a lot, some says like add SPS and PPS.

  const uint8_t sps[] = { 0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0x00,
  
  0x0a, 0xf8, 0x41, 0xa2 };
  
  const uint8_t pps[] = { 0x00, 0x00, 0x00, 0x01, 0x68, 0xce,
  
  0x38, 0x80 };

  So i added the above value to video file before i add the image stream. But no luck.
  Can anyone help on this..Thanks in advance.

  const uint8_t sps[] = { 0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0x00,
  
  0x0a, 0xf8, 0x41, 0xa2 };
  
  const uint8_t pps[] = { 0x00, 0x00, 0x00, 0x01, 0x68, 0xce,
  
  0x38, 0x80 };
  
  const uint8_t slice_header[] = { 0x00, 0x00, 0x00, 0x01, 0x05, 0x88,
  
  0x84, 0x21, 0xa0 };
  
  const uint8_t macroblock_header[] = { 0x0d, 0x00 };
  
  
  
  const uint8_t spspps[] = { 0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0x00, 0x0a, 0xf8, 0x41, 0xa2, 
  
                             0x00, 0x00, 0x00, 0x01, 0x68, 0xce, 0x38, 0x80
  
                           };
  
  
  
  int ff_load_image(uint8_t *data[4], int linesize[4],
  
          int *w, int *h, enum PixelFormat *pix_fmt,
  
          const char *filename, void *log_ctx)
  
      {
  
          AVInputFormat *iformat = NULL;
  
          AVFormatContext *format_ctx = NULL;
  
          AVCodec *codec=NULL;
  
          AVCodecContext *codec_ctx=NULL;
  
          AVFrame *frame=NULL;
  
          int frame_decoded, ret = 0;
  
          AVPacket pkt;
  
  
  
          av_register_all();
  
  
  
          iformat = av_find_input_format("image2");
  
          if ((ret = avformat_open_input(&format_ctx, filename, iformat, NULL)) < 0) {
  
              return ret;
  
          }
  
  
  
          codec_ctx = format_ctx->streams[0]->codec;
  
          codec = avcodec_find_decoder(codec_ctx->codec_id);
  
          if (!codec) {
  
              ret = AVERROR(EINVAL);
  
              goto end;
  
          }
  
  
  
          if ((ret = avcodec_open2(codec_ctx, codec, NULL)) < 0) {
  
              goto end;
  
          }
  
  
  
          //if (!(frame = avcodec_alloc_frame()) ) {
  
          if (!(frame = av_frame_alloc()) ) {
  
              ret = AVERROR(ENOMEM);
  
              goto end;
  
          }
  
  
  
          ret = av_read_frame(format_ctx, &pkt);
  
          if (ret < 0) {
  
              goto end;
  
          }
  
  
  
          ret = avcodec_decode_video2(codec_ctx, frame, &frame_decoded, &pkt);
  
          if (ret < 0 || !frame_decoded) {
  
              goto end;
  
          }
  
          ret = 0;
  
  
  
          *w       = frame->width;
  
          *h       = frame->height;
  
          *pix_fmt = (PixelFormat)frame->format;
  
  
  
          if ((ret = av_image_alloc(data, linesize, *w, *h, (AVPixelFormat)*pix_fmt, 16)) < 0)
  
              goto end;
  
          ret = 0;
  
  
  
          av_image_copy(data, linesize, (const uint8_t **)frame->data, frame->linesize, (AVPixelFormat)*pix_fmt, *w, *h);
  
  
  
  end:
  
          if(codec_ctx) { avcodec_close(codec_ctx); }
  
          if(format_ctx) { avformat_close_input(&format_ctx); }
  
          if(frame) { av_freep(&frame); }
  
          av_free_packet(&pkt);
  
                  return ret;
  
      }
  
  
  
      int load_image_into_frame(AVFrame *frame, const char *filename)
  
      {
  
          int retval = -1, res;
  
          static struct SwsContext *sws_ctx;
  
          uint8_t *image_data[4];
  
          int linesize[4];
  
          int source_width, source_height;
  
          enum PixelFormat source_fmt;
  
  
  
          res = ff_load_image(image_data, linesize, &source_width, &source_height, &source_fmt, filename, NULL);
  
  
  
          if (source_fmt != frame->format) {
  
              sws_ctx = sws_getContext(source_width, source_height, (AVPixelFormat)source_fmt,
  
                  frame->width, frame->height, (AVPixelFormat)frame->format,
  
                  sws_flags, NULL, NULL, NULL);
  
  
  
              sws_scale(sws_ctx,
  
                  (const uint8_t * const *)image_data, linesize,
  
                  0, frame->height, frame->data, frame->linesize);
  
          }
  
  
  
          retval = 0;
  
  error:
  
          av_freep(&image_data[0]);
  
          sws_freeContext(sws_ctx);
  
          return retval;
  
      }
  
  
  
      int write_frame_to_file(FILE *file, AVFrame *frame, AVCodecContext *codec_context, AVPacket *pkt) {
  
          int res, got_output;
  
          av_init_packet(pkt);
  
          pkt->data = NULL;
  
          pkt->size = 0;
  
  
  
          /* generate synthetic video */
  
          frame->pts += 30;
  
  
  
          res = avcodec_encode_video2(codec_context, pkt, frame, &got_output);
  
  
  
          if (got_output) {
  
  
  
              fwrite(pkt->data, 1, pkt->size, file);
  
              av_free_packet(pkt);
  
          }
  
          return 0;
  
  error:
  
          return -1;
  
      }
  
  
  
      int write_image_to_file(FILE *file, const char *filename, int count, AVFrame *frame, AVCodecContext *codec_context, AVPacket *pkt) {
  
          int res, i;
  
          res = load_image_into_frame(frame, filename);
  
  
  
          for (i = 0; i < count; i++) {
  
  
  
              res = write_frame_to_file(file, frame, codec_context, pkt);
  
          }
  
  
  
          return 0;
  
  error:
  
          return -1;
  
      }
  
  
  
      int write_delayed_frames_to_file(FILE *file, AVFrame *frame, AVCodecContext *codec_context, AVPacket *pkt) {
  
          int res, got_output;
  
  
  
          for (got_output = 1; got_output;) {
  
              res = avcodec_encode_video2(codec_context, pkt, NULL, &got_output);
  
  
  
              if (got_output) {
  
                  fwrite(pkt->data, 1, pkt->size, file);
  
                  av_free_packet(pkt);
  
              }
  
          }
  
  
  
          return 0;
  
  error:
  
          return -1;
  
      }
  
  
  
      AVCodecContext *get_codec_context(int width, int height, int fps)
  
      {
  
          int res;
  
          avcodec_register_all();
  
  
  
          AVCodec *codec;
  
          AVCodecContext *codec_context = NULL;
  
  
  
          codec = avcodec_find_encoder(AV_CODEC_ID_H264);
  
  
  
          codec_context = avcodec_alloc_context3(codec);
  
  
  
          codec_context->bit_rate = 441000;
  
          codec_context->width = width;
  
          codec_context->height = height;
  
          AVRational temp_113 = {1, fps};
  
          AVRational temp_114 = {fps, 1};
  
          codec_context->time_base= temp_113;
  
          codec_context->gop_size = 10;
  
          codec_context->max_b_frames=1;
  
          codec_context->pix_fmt = AV_PIX_FMT_YUV420P;        
  
  
  
          res = avcodec_open2(codec_context, codec, NULL);
  
  
  
          return codec_context;
  
  error:
  
          return NULL;
  
      }
  
  
  
      AVFrame *get_av_frame(AVCodecContext *codec_context) {
  
          int res;
  
          AVFrame *frame;
  
  
  
          frame = av_frame_alloc();
  
          frame->height = codec_context->height;
  
          frame->width = codec_context->width;
  
          frame->format = codec_context->pix_fmt;
  
          frame->pts = 0;
  
  
  
          res = av_image_alloc(frame->data, frame->linesize, frame->width, frame->height, (AVPixelFormat)frame->format, 1);
  
  
  
          return frame;
  
  error:
  
          return NULL;
  
      }
  
  
  
      int main(int argc, char **argv)
  
      {
  
          const char *filename = "result video\\test.mp4";
  
          FILE *file=NULL;
  
          int res, retval=-1;
  
          AVCodecContext *codec_context= NULL;
  
          AVFrame *frame=NULL;
  
          AVPacket pkt;
  
          uint8_t endcode[] = { 0, 0, 1, 0xb7 };
  
  
  
          codec_context = get_codec_context(1920, 1080, 30);
  
  
  
          file = fopen(filename, "wb");
  
          //check(file != NULL, "could not open destination file %s", filename);
  
  
  
          frame = get_av_frame(codec_context);        
  
  
  
          //fwrite(sps, 1, sizeof(sps), file);
  
          //fwrite(pps, 1, sizeof(pps), file);
  
  
  
          /*codec_context->extradata = (uint8_t *)malloc(sizeof(uint8_t) * sizeof(spspps));
  
  
  
          for(unsigned int index = 0; index < sizeof(spspps); index++)
  
          {
  
              codec_context->extradata[index] = spspps[index];
  
          }
  
  
  
          codec_context->extradata_size = (int)sizeof(spspps);*/
  
  
  
          codec_context->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
  
  
          int i, frames= 51;
  
          for (i = 0; i < frames; i++) {
  
              std::stringstream ss;
  
              ss<<"\\frames\\out"<<( i + 1)<<".jpg";
  
              res = write_image_to_file(file, ss.str().c_str(), 3, frame, codec_context, &pkt);
  
          }
  
  
  
  
  
          res = write_delayed_frames_to_file(file, frame, codec_context, &pkt);
  
          fwrite(endcode, 1, sizeof(endcode), file);
  
  
  
          retval = 0;
  
  error:
  
          if (file)
  
              fclose(file);
  
          if (codec_context) {
  
              avcodec_close(codec_context);
  
              av_free(codec_context);
  
          }
  
          if (frame) {
  
              av_freep(&frame->data[0]);
  
              av_free(frame);
  
          }
  
          return retval;
  
      }
  
  }

• Why JPEG image looks different in two videos ?

  28 septembre 2015, par user606521

  I have two frames :

  f1.jpg
  
  f2.jpg
  

  And I am creating two videos :

  ./ffmpeg -i ./f%d.jpg -r 30 -y m1.mp4 # both frames 1 and 2
  
  ./ffmpeg -i ./f2.jpg -r 30 -y m2.mp4 # only frame 2

  For some reason frame 2 looks different in these two videos

  Frame 2 from m1.mp4 :

  $ ./ffmpeg -i m1.mp4 out1_%d.jpg
  
  ffmpeg version 2.7.2 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with llvm-gcc 4.2.1 (LLVM build 2336.11.00)
  
    configuration: --prefix=/Volumes/Ramdisk/sw --enable-gpl --enable-pthreads --enable-version3 --enable-libspeex --enable-libvpx --disable-decoder=libvpx --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-avfilter --enable-libopencore_amrwb --enable-libopencore_amrnb --enable-filters --enable-libgsm --enable-libvidstab --enable-libx265 --disable-doc --arch=x86_64 --enable-runtime-cpudetect
  
    libavutil      54. 27.100 / 54. 27.100
  
    libavcodec     56. 41.100 / 56. 41.100
  
    libavformat    56. 36.100 / 56. 36.100
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 16.101 /  5. 16.101
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.100 /  1.  2.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'm1.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf56.36.100
  
    Duration: 00:00:00.07, start: 0.000000, bitrate: 478 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 980x100, 381 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
  [swscaler @ 0x7f7f9a000600] deprecated pixel format used, make sure you did set range correctly
  
  Output #0, image2, to 'out1_%d.jpg':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf56.36.100
  
      Stream #0:0(und): Video: mjpeg, yuvj420p(pc), 980x100, q=2-31, 200 kb/s, 30 fps, 30 tbn, 30 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
        encoder         : Lavc56.41.100 mjpeg
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
  
  Press [q] to stop, [?] for help
  
  frame=    2 fps=0.0 q=1.6 Lsize=N/A time=00:00:00.06 bitrate=N/A    
  
  video:6kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

  

  Frame 2 from m2.mp4 :

  $ ./ffmpeg -i m2.mp4 out2_%d.jpg
  
  ffmpeg version 2.7.2 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with llvm-gcc 4.2.1 (LLVM build 2336.11.00)
  
    configuration: --prefix=/Volumes/Ramdisk/sw --enable-gpl --enable-pthreads --enable-version3 --enable-libspeex --enable-libvpx --disable-decoder=libvpx --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-avfilter --enable-libopencore_amrwb --enable-libopencore_amrnb --enable-filters --enable-libgsm --enable-libvidstab --enable-libx265 --disable-doc --arch=x86_64 --enable-runtime-cpudetect
  
    libavutil      54. 27.100 / 54. 27.100
  
    libavcodec     56. 41.100 / 56. 41.100
  
    libavformat    56. 36.100 / 56. 36.100
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 16.101 /  5. 16.101
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.100 /  1.  2.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'm2.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf56.36.100
  
    Duration: 00:00:00.03, start: 0.000000, bitrate: 824 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc), 980x100 [SAR 1:1 DAR 49:5], 648 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
  Output #0, image2, to 'out2_%d.jpg':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf56.36.100
  
      Stream #0:0(und): Video: mjpeg, yuvj420p(pc), 980x100 [SAR 1:1 DAR 49:5], q=2-31, 200 kb/s, 30 fps, 30 tbn, 30 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
        encoder         : Lavc56.41.100 mjpeg
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
  
  Press [q] to stop, [?] for help
  
  frame=    1 fps=0.0 q=1.6 Lsize=N/A time=00:00:00.03 bitrate=N/A    
  
  video:4kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

  

  It seems that frame 2 looks different when combined with frame 1 in a video. One thing I noticed that when dumping frames from m1.mp4 (two frames combined) there is a warning in ffmpeg output :

  [swscaler @ 0x7f7f9a000600] deprecated pixel format used, make sure you did set range correctly

  Also two frame images have same dimmensions (980x100) and their format seems to be same :

  $ file -b f1.jpg
  
  JPEG image data, JFIF standard 1.01, comment: "CS=ITU601??"
  
  $ file -b f2.jpg 
  
  JPEG image data, JFIF standard 1.01

  So why this is happening ? I am struggling with this issue for quite a long time - for some reason some JPEGs somehow are in different "format ?" than others and make mess in videos...

  ---

  You can download first two images included in this question and test commands on your own.

  ---

  $ identify -verbose f1.jpg
  
  Image: f1.jpg
  
    Format: JPEG (Joint Photographic Experts Group JFIF format)
  
    Mime type: image/jpeg
  
    Class: DirectClass
  
    Geometry: 980x100+0+0
  
    Resolution: 552x551
  
    Print size: 1.77536x0.181488
  
    Units: PixelsPerInch
  
    Type: Palette
  
    Endianess: Undefined
  
    Colorspace: sRGB
  
    Depth: 8-bit
  
    Channel depth:
  
      red: 8-bit
  
      green: 8-bit
  
      blue: 8-bit
  
    Channel statistics:
  
      Red:
  
        min: 189 (0.741176)
  
        max: 233 (0.913725)
  
        mean: 208.261 (0.81671)
  
        standard deviation: 14.1741 (0.0555848)
  
        kurtosis: -1.40078
  
        skewness: 0.332664
  
      Green:
  
        min: 189 (0.741176)
  
        max: 233 (0.913725)
  
        mean: 208.261 (0.81671)
  
        standard deviation: 14.1741 (0.0555848)
  
        kurtosis: -1.40078
  
        skewness: 0.332664
  
      Blue:
  
        min: 189 (0.741176)
  
        max: 233 (0.913725)
  
        mean: 208.26 (0.816706)
  
        standard deviation: 14.1756 (0.0555905)
  
        kurtosis: -1.40068
  
        skewness: 0.332424
  
    Image statistics:
  
      Overall:
  
        min: 189 (0.741176)
  
        max: 233 (0.913725)
  
        mean: 208.261 (0.816709)
  
        standard deviation: 14.1746 (0.0555867)
  
        kurtosis: -1.40075
  
        skewness: 0.332584
  
    Colors: 47
  
    Histogram:
  
         368: (189,189,189) #BDBDBD grey74
  
        1984: (190,190,190) #BEBEBE grey
  
          28: (191,191,189) #BFBFBD srgb(191,191,189)
  
        3780: (191,191,191) #BFBFBF grey75
  
          28: (192,192,190) #C0C0BE srgb(192,192,190)
  
        6628: (192,192,192) #C0C0C0 silver
  
        5664: (193,193,193) #C1C1C1 srgb(193,193,193)
  
        4608: (194,194,194) #C2C2C2 grey76
  
        4480: (195,195,195) #C3C3C3 srgb(195,195,195)
  
        3328: (196,196,196) #C4C4C4 grey77
  
        2592: (197,197,197) #C5C5C5 srgb(197,197,197)
  
        3072: (198,198,198) #C6C6C6 srgb(198,198,198)
  
        2272: (199,199,199) #C7C7C7 grey78
  
        2112: (200,200,200) #C8C8C8 srgb(200,200,200)
  
        2112: (201,201,201) #C9C9C9 grey79
  
        1920: (202,202,202) #CACACA srgb(202,202,202)
  
        1728: (203,203,203) #CBCBCB srgb(203,203,203)
  
        1760: (204,204,204) #CCCCCC grey80
  
        1696: (205,205,205) #CDCDCD srgb(205,205,205)
  
        1248: (206,206,206) #CECECE srgb(206,206,206)
  
        1536: (207,207,207) #CFCFCF grey81
  
        1504: (208,208,208) #D0D0D0 srgb(208,208,208)
  
        1344: (209,209,209) #D1D1D1 grey82
  
        1536: (210,210,210) #D2D2D2 srgb(210,210,210)
  
        1472: (211,211,211) #D3D3D3 LightGray
  
        1088: (212,212,212) #D4D4D4 grey83
  
        1472: (213,213,213) #D5D5D5 srgb(213,213,213)
  
        1536: (214,214,214) #D6D6D6 grey84
  
        1344: (215,215,215) #D7D7D7 srgb(215,215,215)
  
        1184: (216,216,216) #D8D8D8 srgb(216,216,216)
  
        1408: (217,217,217) #D9D9D9 grey85
  
        1472: (218,218,218) #DADADA srgb(218,218,218)
  
        1216: (219,219,219) #DBDBDB grey86
  
        1280: (220,220,220) #DCDCDC gainsboro
  
        1536: (221,221,221) #DDDDDD srgb(221,221,221)
  
        1472: (222,222,222) #DEDEDE grey87
  
        1600: (223,223,223) #DFDFDF srgb(223,223,223)
  
        1696: (224,224,224) #E0E0E0 grey88
  
        1792: (225,225,225) #E1E1E1 srgb(225,225,225)
  
        1728: (226,226,226) #E2E2E2 srgb(226,226,226)
  
        1952: (227,227,227) #E3E3E3 grey89
  
        2272: (228,228,228) #E4E4E4 srgb(228,228,228)
  
        2752: (229,229,229) #E5E5E5 grey90
  
        4512: (230,230,230) #E6E6E6 srgb(230,230,230)
  
        4672: (231,231,231) #E7E7E7 srgb(231,231,231)
  
         640: (232,232,232) #E8E8E8 grey91
  
         576: (233,233,233) #E9E9E9 srgb(233,233,233)
  
    Rendering intent: Perceptual
  
    Gamma: 0.454545
  
    Chromaticity:
  
      red primary: (0.64,0.33)
  
      green primary: (0.3,0.6)
  
      blue primary: (0.15,0.06)
  
      white point: (0.3127,0.329)
  
    Background color: white
  
    Border color: srgb(223,223,223)
  
    Matte color: grey74
  
    Transparent color: black
  
    Interlace: None
  
    Intensity: Undefined
  
    Compose: Over
  
    Page geometry: 980x100+0+0
  
    Dispose: Undefined
  
    Iterations: 0
  
    Compression: JPEG
  
    Orientation: Undefined
  
    Properties:
  
      comment: CS=ITU601
  
      date:create: 2015-09-28T21:47:26+02:00
  
      date:modify: 2015-09-28T21:47:26+02:00
  
      jpeg:colorspace: 2
  
      jpeg:quality: 92
  
      jpeg:sampling-factor: 2x2,1x1,1x1
  
      signature: ca599d8ad07c79b36837cb9f4811d83e236b8d4a4cdfada8d60c4aa330f28f38
  
    Artifacts:
  
      filename: f1.jpg
  
      verbose: true
  
    Tainted: False
  
    Filesize: 1.36KB
  
    Number pixels: 98K
  
    Pixels per second: 9.8MB
  
    User time: 0.000u
  
    Elapsed time: 0:01.009
  
    Version: ImageMagick 6.8.7-0 2013-10-28 Q16 http://www.imagemagick.org

  ---

  $ identify -verbose f2.jpg
  
  Image: f2.jpg
  
    Format: JPEG (Joint Photographic Experts Group JFIF format)
  
    Mime type: image/jpeg
  
    Class: DirectClass
  
    Geometry: 980x100+0+0
  
    Resolution: 72x72
  
    Print size: 13.6111x1.38889
  
    Units: PixelsPerInch
  
    Type: Palette
  
    Endianess: Undefined
  
    Colorspace: sRGB
  
    Depth: 8-bit
  
    Channel depth:
  
      red: 8-bit
  
      green: 8-bit
  
      blue: 8-bit
  
    Channel statistics:
  
      Red:
  
        min: 186 (0.729412)
  
        max: 254 (0.996078)
  
        mean: 242.844 (0.952329)
  
        standard deviation: 11.0845 (0.0434688)
  
        kurtosis: 4.24417
  
        skewness: -2.17102
  
      Green:
  
        min: 186 (0.729412)
  
        max: 254 (0.996078)
  
        mean: 242.844 (0.952329)
  
        standard deviation: 11.0845 (0.0434688)
  
        kurtosis: 4.24417
  
        skewness: -2.17102
  
      Blue:
  
        min: 186 (0.729412)
  
        max: 254 (0.996078)
  
        mean: 242.842 (0.952323)
  
        standard deviation: 11.0886 (0.0434848)
  
        kurtosis: 4.24235
  
        skewness: -2.17103
  
    Image statistics:
  
      Overall:
  
        min: 186 (0.729412)
  
        max: 254 (0.996078)
  
        mean: 242.843 (0.952327)
  
        standard deviation: 11.0859 (0.0434741)
  
        kurtosis: 4.24356
  
        skewness: -2.17102
  
    Colors: 91
  
    Histogram:
  
           2: (186,186,186) #BABABA grey73
  
           2: (187,187,187) #BBBBBB srgb(187,187,187)
  
           1: (189,189,189) #BDBDBD grey74
  
           5: (190,190,190) #BEBEBE grey
  
           2: (191,191,191) #BFBFBF grey75
  
          20: (192,192,192) #C0C0C0 silver
  
          28: (193,193,193) #C1C1C1 srgb(193,193,193)
  
          37: (194,194,194) #C2C2C2 grey76
  
          46: (195,195,195) #C3C3C3 srgb(195,195,195)
  
          59: (196,196,196) #C4C4C4 grey77
  
         108: (197,197,197) #C5C5C5 srgb(197,197,197)
  
         134: (198,198,198) #C6C6C6 srgb(198,198,198)
  
         145: (199,199,199) #C7C7C7 grey78
  
         188: (200,200,200) #C8C8C8 srgb(200,200,200)
  
         230: (201,201,201) #C9C9C9 grey79
  
         241: (202,202,202) #CACACA srgb(202,202,202)
  
         236: (203,203,203) #CBCBCB srgb(203,203,203)
  
         252: (204,204,204) #CCCCCC grey80
  
         240: (205,205,205) #CDCDCD srgb(205,205,205)
  
         243: (206,206,206) #CECECE srgb(206,206,206)
  
           1: (207,207,205) #CFCFCD srgb(207,207,205)
  
         250: (207,207,207) #CFCFCF grey81
  
           1: (208,208,206) #D0D0CE srgb(208,208,206)
  
         267: (208,208,208) #D0D0D0 srgb(208,208,208)
  
           2: (209,209,207) #D1D1CF srgb(209,209,207)
  
         226: (209,209,209) #D1D1D1 grey82
  
           3: (210,210,208) #D2D2D0 srgb(210,210,208)
  
         193: (210,210,210) #D2D2D2 srgb(210,210,210)
  
           5: (211,211,209) #D3D3D1 srgb(211,211,209)
  
         215: (211,211,211) #D3D3D3 LightGray
  
           7: (212,212,210) #D4D4D2 srgb(212,212,210)
  
         227: (212,212,212) #D4D4D4 grey83
  
          11: (213,213,211) #D5D5D3 srgb(213,213,211)
  
         250: (213,213,213) #D5D5D5 srgb(213,213,213)
  
           4: (214,214,212) #D6D6D4 srgb(214,214,212)
  
         291: (214,214,214) #D6D6D6 grey84
  
          16: (215,215,213) #D7D7D5 srgb(215,215,213)
  
         307: (215,215,215) #D7D7D7 srgb(215,215,215)
  
           1: (216,216,214) #D8D8D6 srgb(216,216,214)
  
         371: (216,216,216) #D8D8D8 srgb(216,216,216)
  
           4: (217,217,215) #D9D9D7 srgb(217,217,215)
  
         355: (217,217,217) #D9D9D9 grey85
  
           3: (218,218,216) #DADAD8 srgb(218,218,216)
  
         398: (218,218,218) #DADADA srgb(218,218,218)
  
           3: (219,219,217) #DBDBD9 srgb(219,219,217)
  
         404: (219,219,219) #DBDBDB grey86
  
           5: (220,220,218) #DCDCDA srgb(220,220,218)
  
         435: (220,220,220) #DCDCDC gainsboro
  
           1: (221,221,219) #DDDDDB srgb(221,221,219)
  
         489: (221,221,221) #DDDDDD srgb(221,221,221)
  
           2: (222,222,220) #DEDEDC srgb(222,222,220)
  
         569: (222,222,222) #DEDEDE grey87
  
           1: (223,223,221) #DFDFDD srgb(223,223,221)
  
         552: (223,223,223) #DFDFDF srgb(223,223,223)
  
           2: (224,224,222) #E0E0DE srgb(224,224,222)
  
         595: (224,224,224) #E0E0E0 grey88
  
           2: (225,225,223) #E1E1DF srgb(225,225,223)
  
         645: (225,225,225) #E1E1E1 srgb(225,225,225)
  
         736: (226,226,226) #E2E2E2 srgb(226,226,226)
  
           3: (227,227,225) #E3E3E1 srgb(227,227,225)
  
         646: (227,227,227) #E3E3E3 grey89
  
           1: (228,228,226) #E4E4E2 srgb(228,228,226)
  
         707: (228,228,228) #E4E4E4 srgb(228,228,228)
  
           1: (229,229,227) #E5E5E3 srgb(229,229,227)
  
         667: (229,229,229) #E5E5E5 grey90
  
           1: (230,230,228) #E6E6E4 srgb(230,230,228)
  
         759: (230,230,230) #E6E6E6 srgb(230,230,230)
  
         767: (231,231,231) #E7E7E7 srgb(231,231,231)
  
         788: (232,232,232) #E8E8E8 grey91
  
         862: (233,233,233) #E9E9E9 srgb(233,233,233)
  
         880: (234,234,234) #EAEAEA srgb(234,234,234)
  
         889: (235,235,235) #EBEBEB grey92
  
         863: (236,236,236) #ECECEC srgb(236,236,236)
  
         868: (237,237,237) #EDEDED grey93
  
        1032: (238,238,238) #EEEEEE srgb(238,238,238)
  
         878: (239,239,239) #EFEFEF srgb(239,239,239)
  
        1083: (240,240,240) #F0F0F0 grey94
  
        1035: (241,241,241) #F1F1F1 srgb(241,241,241)
  
        1247: (242,242,242) #F2F2F2 grey95
  
        1610: (243,243,243) #F3F3F3 srgb(243,243,243)
  
        2084: (244,244,244) #F4F4F4 srgb(244,244,244)
  
        3473: (245,245,245) #F5F5F5 grey96
  
        6350: (246,246,246) #F6F6F6 srgb(246,246,246)
  
        9152: (247,247,247) #F7F7F7 grey97
  
       14755: (248,248,248) #F8F8F8 srgb(248,248,248)
  
       21183: (249,249,249) #F9F9F9 srgb(249,249,249)
  
       12507: (250,250,250) #FAFAFA grey98
  
        2516: (251,251,251) #FBFBFB srgb(251,251,251)
  
         305: (252,252,252) #FCFCFC grey99
  
          16: (253,253,253) #FDFDFD srgb(253,253,253)
  
           4: (254,254,254) #FEFEFE srgb(254,254,254)
  
    Rendering intent: Perceptual
  
    Gamma: 0.454545
  
    Chromaticity:
  
      red primary: (0.64,0.33)
  
      green primary: (0.3,0.6)
  
      blue primary: (0.15,0.06)
  
      white point: (0.3127,0.329)
  
    Background color: white
  
    Border color: srgb(223,223,223)
  
    Matte color: grey74
  
    Transparent color: black
  
    Interlace: None
  
    Intensity: Undefined
  
    Compose: Over
  
    Page geometry: 980x100+0+0
  
    Dispose: Undefined
  
    Iterations: 0
  
    Compression: JPEG
  
    Orientation: Undefined
  
    Properties:
  
      date:create: 2015-09-28T21:48:30+02:00
  
      date:modify: 2015-09-28T21:48:30+02:00
  
      jpeg:colorspace: 2
  
      jpeg:quality: 92
  
      jpeg:sampling-factor: 2x2,1x1,1x1
  
      signature: f718ab157fae4ff0395eaf07a0165897fd9de558eaed00586530690d39e5ed23
  
    Artifacts:
  
      filename: f2.jpg
  
      verbose: true
  
    Tainted: False
  
    Filesize: 4.32KB
  
    Number pixels: 98K
  
    Pixels per second: 0B
  
    User time: 0.000u
  
    Elapsed time: 0:01.000
  
    Version: ImageMagick 6.8.7-0 2013-10-28 Q16 http://www.imagemagick.org

• equivalent option in ffmpeg for ffplay's -infbuff

  25 septembre 2015, par Paul

  I have a multicast UDP stream that I can watch (with almost no errors) if I use ffplay’s infbuf option.

  But when I try to encode it via ffmpeg, ffmpeg reports a lot of errors and the resultant video has lots of errors.

  I have tried setting the fifo_size to a super large value like 655360 and the buf_size as per https://www.ffmpeg.org/ffmpeg-protocols.html#udp. But none of gets rid of the decode errors in ffmpeg.

  Is it possible to provide settings to ffmpeg that do something similar to what ffplay’s -intbuf does ? I want my video encode to be as error free as video playback via ffplay.