Sur d’autres sites (7439)

• Date and segment comparison feature

  31 octobre 2019, par Matomo Core Team — Analytics Tips, Development

  Get a clearer picture with the date and segment comparison feature

  What can you do with it ? What are the benefits ?

  Make informed decisions faster by easily comparing different segments and dates with each other.

  Compare report data for multiple segments next to each other

  

  Directly compare the behaviour of visitors from different segments e.g. customers with accounts vs. customers without accounts. Segment comparisons are a powerful way to compare different audience ; learn which ones perform better ; and in what way their actions differ. 

  Compare report data for two time periods next to each other

  

  See how your website performs compared to the previous month/week/year. Including seeing trends over those periods. Say, your business always picks up at the same times within a year, or there’s a sag in business for every user segment over this year and the last except one.

  By being able to compare date ranges you are able to get a quick overview of trends and period to period performance. Has a campaign worked better in September than in October ? Get an instant look by having the side-by-side comparison in Matomo.

  What is it capable of ?

  It lets you ask the question, “What is different ?”

  If you look at reports you’ll only see how people behave overall and if you look at specific segments you’ll see how they behave at face value, however, if you compare data together you’ll be quickly informed on what makes them unique. This data is still there when you don’t use the comparison feature, it’s just buried. Comparing data highlights discrepancies and leads to important questions and answers.

  For example, perhaps some class of users have very low engagement on a specific day compared to the rest of your visitors, and perhaps those users are responsible for an outsized proportion of churn. 

  Who could benefit from it, and why ?

  Everyone can benefit from using it (and probably should use it). It’s yours to experiment with ! You shouldn’t feel restricted to only comparing between the current and last period, or having questions before you start comparing. Follow your instincts and see what pops out when data from different segments is laid out next to each other.

  Where can you find it in Matomo ?

  • Segment comparison is activated by the new icon in the segment selector

  

  • Date comparison can be found in the calendar section of Matomo

  

  • The list of active comparisons is visible at the top of the page for all pages that support comparison
  • Comparisons are visible in every report that supports comparing data, and reports that do not support it will display a message saying so

  How do you use it ?

  • To compare segments, click the icon in the segment selector
  • To compare periods, click the ‘compare’ checkbox in the period selector, then select what period you want to compare it against in the dropdown (previous period, previous year, or a custom range)
  • When comparisons are active, view your reports as normal

  Take it away !

  The comparison feature is a new tool from Matomo 3.12.0 that highlights discrepancies and differences in data that can lead to more clarity and understanding, so we’d encourage everyone to use it. 

  Try it out today in your Matomo and see the power behind this new data comparison mode !

• MP3 files created using FFmpeg are not starting playback in browser immediately. Is there any major difference between FFmpeg and AVCONV ?

  23 janvier 2019, par AR5

  I am working on a website that streams music. We recently changed server from Debian (with avconv) to a Centos7 (with FFmpeg) server.
  The mp3 files created on Debian server start playback on browser (I have tested Chrome and Firefox) start almost at the same time they start loading into the browser (I used Network tab on Developer Tools to monitor this)

  Now after the switch to Centos/FFmpeg server, the files being created on this new server are displaying a strange behavior. They only start playback after about 1MB is loaded into the browser.

  I have used identical settings for converting original file into MP3 in both AVCONV and FFmpeg but the files created using FFmpeg are showing this issue. Is there something that might be causing such an issue ? Are there differences in terms of audio conversion between AVCONV and FFmpeg ?

  I have already tried

  I first found that the files created on old server (Debian/Avconv) were VBR (variable bitrate) and the ones created on new server were CBR (constant bitrate), so I tried switching to VBR but the issue still persisted.

  I checked the mp3 files using MediaInfo app and there seems to be no difference between the files.

  I also checked if both files were being served as 206 Partial Content and they both are indeed.

  I am trying to create mp3 files using FFmpeg that work exactly like the ones created before using avconv

  I am trying to make the streaming site work on the new server but the mp3 files created using FFmpeg are not playing back correctly as compared to the ones created on the old server. I am trying to figure out what I might be doing wrong ? or if there is a difference between avconv and FFmpeg that is causing this issue.

  I am really stuck on this issue, any help will be really appreciated.

  ---

  Edit

  I don’t have access to old server anymore so I couldn’t retrieve the log output of avconv. The command that I was using was as follows :

  avconv -y -i "/test/Track 01.mp3" -ac 2 -ar 44100 -acodec libmp3lame -b:a 128k "/test/Track 01 (converted).mp3"

  Here is the command and log output from new server :

  ffmpeg -y -i "/test/Track 01.mp3" -ac 2 -ar 44100 -acodec libmp3lame -b:a 128k "/test/Track 01 (converted).mp3"
  
  ffmpeg version 2.8.15 Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-28)
  
    configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --optflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic' --extra-ldflags='-Wl,-z,relro ' --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libvo-amrwbenc --enable-version3 --enable-bzlib --disable-crystalhd --enable-gnutls --enable-ladspa --enable-libass --enable-libcdio --enable-libdc1394 --disable-indev=jack --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-openal --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libv4l2 --enable-libx264 --enable-libx265 --enable-libxvid --enable-x11grab --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib64 --enable-runtime-cpudetect
  
    libavutil      54. 31.100 / 54. 31.100
  
    libavcodec     56. 60.100 / 56. 60.100
  
    libavformat    56. 40.101 / 56. 40.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 40.101 /  5. 40.101
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.101 /  1.  2.101
  
    libpostproc    53.  3.100 / 53.  3.100
  
  [mp3 @ 0xd60be0] Skipping 0 bytes of junk at 240044.
  
  Input #0, mp3, from '/test/Track 01.mp3':
  
    Metadata:
  
      album           : Future Hndrxx Presents: The WIZRD
  
      artist          : Future
  
      genre           : Hip-Hop
  
      title           : Never Stop
  
      track           : 1
  
      lyrics-eng      : rgf.is
  
      WEB SITE        : rgf.is
  
      TAGGINGTIME     : rgf.is
  
      WEB             : rgf.is
  
      date            : 2019
  
      encoder         : Lavf56.40.101
  
    Duration: 00:04:51.40, start: 0.025056, bitrate: 121 kb/s
  
      Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 114 kb/s
  
      Metadata:
  
        encoder         : Lavc56.60
  
      Stream #0:1: Video: png, rgb24(pc), 333x333 [SAR 1:1 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
  
      Metadata:
  
        comment         : Cover (front)
  
  [mp3 @ 0xd66ec0] Frame rate very high for a muxer not efficiently supporting it.
  
  Please consider specifying a lower framerate, a different muxer or -vsync 2
  
  Output #0, mp3, to '/test/Track 01 (converted).mp3':
  
    Metadata:
  
      TALB            : Future Hndrxx Presents: The WIZRD
  
      TPE1            : Future
  
      TCON            : Hip-Hop
  
      TIT2            : Never Stop
  
      TRCK            : 1
  
      lyrics-eng      : rgf.is
  
      WEB SITE        : rgf.is
  
      TAGGINGTIME     : rgf.is
  
      WEB             : rgf.is
  
      TDRC            : 2019
  
      TSSE            : Lavf56.40.101
  
      Stream #0:0: Video: png, rgb24, 333x333 [SAR 1:1 DAR 1:1], q=2-31, 200 kb/s, 90k fps, 90k tbn, 90k tbc
  
      Metadata:
  
        comment         : Cover (front)
  
        encoder         : Lavc56.60.100 png
  
      Stream #0:1: Audio: mp3 (libmp3lame), 44100 Hz, stereo, s16p, 128 kb/s
  
      Metadata:
  
        encoder         : Lavc56.60.100 libmp3lame
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (png (native) -> png (native))
  
    Stream #0:0 -> #0:1 (mp3 (native) -> mp3 (libmp3lame))
  
  Press [q] to stop, [?] for help
  
  [libmp3lame @ 0xd9b0c0] Trying to remove 1152 samples, but the queue is emptys/s
  
  frame=    1 fps=0.1 q=-0.0 Lsize=    4788kB time=00:04:51.39 bitrate= 134.6kbits/s
  
  video:234kB audio:4553kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.014809%

  Samples of MP3 files

  I have uploaded samples of mp3 files created using both avconv and FFmpeg. Please find these here : https://drive.google.com/drive/folders/1gRTmMM2iSK0VWQ4Zaf_iBNQe5laFJl08?usp=sharing

• ffmpeg avcodec_send_packet/avcodec_receive_frame memory leak

  23 janvier 2019, par G Hamlin

  I’m attempting to decode frames, but memory usage grows with every frame (more specifically, with every call to avcodec_send_packet) until finally the code crashes with a bad_alloc. Here’s the basic decode loop :

  int rfret = 0;
  
  while((rfret = av_read_frame(inctx.get(), &packet)) >= 0){
  
      if (packet.stream_index == vstrm_idx) {
  
  
  
          //std::cout << "Sending Packet" << std::endl;
  
          int ret = avcodec_send_packet(ctx.get(), &packet);
  
          if (ret < 0 || ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
  
              std::cout << "avcodec_send_packet: " << ret << std::endl;
  
              break;
  
          }
  
  
  
          while (ret  >= 0) {
  
              //std::cout << "Receiving Frame" << std::endl;
  
              ret = avcodec_receive_frame(ctx.get(), fr);
  
              if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
  
                  //std::cout << "avcodec_receive_frame: " << ret << std::endl;
  
                  av_frame_unref(fr);
  
                  // av_frame_free(&fr);
  
                  break;
  
              }
  
  
  
              std::cout << "frame: " << ctx->frame_number << std::endl;
  
  
  
              // eventually do something with the frame here...
  
  
  
              av_frame_unref(fr);
  
              // av_frame_free(&fr);
  
          }
  
      }
  
      else {
  
          //std::cout << "Not Video" << std::endl;
  
      }
  
      av_packet_unref(&packet);
  
  }

  Memory usage/leakage seems to scale with the resolution of the video I’m decoding. For example, for a 3840x2160 resolution video, the memory usage in windows task manager consistently jumps up by about 8mb (1 byte per pixel ??) for each received frame. Do I need to do something besides call av_frame_unref to release the memory ?

  (more) complete code below

  ---

  void AVFormatContextDeleter(AVFormatContext* ptr)
  
  {
  
      if (ptr) {
  
          avformat_close_input(&ptr);
  
      }
  
  }
  
  
  
  void AVCodecContextDeleter(AVCodecContext* ptr)
  
  {
  
      if (ptr) {
  
          avcodec_free_context(&ptr);
  
      }
  
  }
  
  
  
  typedef std::unique_ptr AVFormatContextPtr;
  
  typedef std::unique_ptr AVCodecContextPtr;
  
  
  
  AVCodecContextPtr createAvCodecContext(AVCodec *vcodec)
  
  {
  
      AVCodecContextPtr ctx(avcodec_alloc_context3(vcodec), AVCodecContextDeleter);
  
      return ctx;
  
  }
  
  
  
  AVFormatContextPtr createFormatContext(const std::string& filename)
  
  {
  
      AVFormatContext* inctxPtr = nullptr;
  
      int ret = avformat_open_input(&inctxPtr, filename.c_str(), nullptr, nullptr);
  
      //    int ret = avformat_open_input(&inctx, "D:/Videos/test.mp4", nullptr, nullptr);
  
      if (ret != 0) {
  
          inctxPtr = nullptr;
  
      }
  
  
  
      return AVFormatContextPtr(inctxPtr, AVFormatContextDeleter);
  
  }
  
  
  
  int testDecode()
  
  {
  
      // open input file context
  
      AVFormatContextPtr inctx = createFormatContext("D:/Videos/Matt Chapman Hi Greg.MOV");
  
  
  
      if (!inctx) {
  
          // std::cerr << "fail to avforamt_open_input(\"" << infile << "\"): ret=" << ret;
  
          return 1;
  
      }
  
  
  
      // retrieve input stream information
  
      int ret = avformat_find_stream_info(inctx.get(), nullptr);
  
      if (ret < 0) {
  
          //std::cerr << "fail to avformat_find_stream_info: ret=" << ret;
  
          return 2;
  
      }
  
  
  
      // find primary video stream
  
      AVCodec* vcodec = nullptr;
  
      const int vstrm_idx = av_find_best_stream(inctx.get(), AVMEDIA_TYPE_VIDEO, -1, -1, &vcodec, 0);
  
      if (vstrm_idx < 0) {
  
          //std::cerr << "fail to av_find_best_stream: vstrm_idx=" << vstrm_idx;
  
          return 3;
  
      }
  
  
  
      AVCodecParameters* origin_par = inctx->streams[vstrm_idx]->codecpar;
  
      if (vcodec == nullptr) {  // is this even necessary?
  
          vcodec = avcodec_find_decoder(origin_par->codec_id);
  
          if (!vcodec) {
  
              // Can't find decoder
  
              return 4;
  
          }
  
      }
  
  
  
      AVCodecContextPtr ctx = createAvCodecContext(vcodec);
  
      if (!ctx) {
  
          return 5;
  
      }
  
  
  
      ret = avcodec_parameters_to_context(ctx.get(), origin_par);
  
      if (ret) {
  
          return 6;
  
      }
  
  
  
      ret = avcodec_open2(ctx.get(), vcodec, nullptr);
  
      if (ret < 0) {
  
          return 7;
  
      }
  
  
  
      //print input video stream informataion
  
      std::cout
  
              //<< "infile: " << infile << "\n"
  
              << "format: " << inctx->iformat->name << "\n"
  
              << "vcodec: " << vcodec->name << "\n"
  
              << "size:   " << origin_par->width << 'x' << origin_par->height << "\n"
  
              << "fps:    " << av_q2d(ctx->framerate) << " [fps]\n"
  
              << "length: " << av_rescale_q(inctx->duration, ctx->time_base, {1,1000}) / 1000. << " [sec]\n"
  
              << "pixfmt: " << av_get_pix_fmt_name(ctx->pix_fmt) << "\n"
  
              << "frame:  " << inctx->streams[vstrm_idx]->nb_frames << "\n"
  
              << std::flush;
  
  
  
  
  
      AVPacket packet;
  
  
  
      av_init_packet(&packet);
  
      packet.data = nullptr;
  
      packet.size = 0;
  
  
  
      AVFrame *fr = av_frame_alloc();
  
      if (!fr) {
  
          return 8;
  
      }
  
  
  
      int rfret = 0;
  
      while((rfret = av_read_frame(inctx.get(), &packet)) >= 0){
  
          if (packet.stream_index == vstrm_idx) {
  
  
  
              //std::cout << "Sending Packet" << std::endl;
  
              int ret = avcodec_send_packet(ctx.get(), &packet);
  
              if (ret < 0 || ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
  
                  std::cout << "avcodec_send_packet: " << ret << std::endl;
  
                  break;
  
              }
  
  
  
              while (ret  >= 0) {
  
                  //std::cout << "Receiving Frame" << std::endl;
  
                  ret = avcodec_receive_frame(ctx.get(), fr);
  
                  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
  
                      //std::cout << "avcodec_receive_frame: " << ret << std::endl;
  
                      av_frame_unref(fr);
  
                      // av_frame_free(&fr);
  
                      break;
  
                  }
  
  
  
                  std::cout << "frame: " << ctx->frame_number << std::endl;
  
  
  
                  // do something with the frame here...
  
  
  
                  av_frame_unref(fr);
  
                  // av_frame_free(&fr);
  
              }
  
          }
  
          else {
  
              //std::cout << "Not Video" << std::endl;
  
          }
  
          av_packet_unref(&packet);
  
      }
  
  
  
      std::cout << "RFRET = " << rfret << std::endl;
  
  
  
      return 0;
  
  }

  Update 1 : (1/21/2019) Compiling on a different machine and running with different video files I am not seeing the memory usage growing without bound. I’ll try to narrow down where the difference lies (compiler ?, ffmpeg version ?, or video encoding ?)

  Update 2 : (1/21/2019) Ok, it looks like there is some interaction occurring between ffmpeg and Qt’s QCamera. In my application, I’m using Qt to manage the webcam, but decided to use ffmpeg libraries to handle decoding/encoding since Qt doesn’t have as comprehensive support for different codecs. If I have the camera turned on (through Qt), ffmpeg decoding memory consumption grows without bound. If the camera is off, ffmpeg behaves fine. I’ve tried this both with a physical camera (Logitech C920) and with a virtual camera using OBS-Virtualcam, with the same result. So far I’m baffled as to how the two systems are interacting...