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• What does "probe_score" means from ffprobe output ?

  13 août 2014, par Drake

  Given a media file, after running ffprobe -i input.mp4 -show_format -print_format json, I got something like this :

  {
  
      "format": {
  
          "filename": "ooxx.mp4",
  
          "nb_streams": 2,
  
          "nb_programs": 0,
  
          "format_name": "mov,mp4,m4a,3gp,3g2,mj2",
  
          "format_long_name": "QuickTime / MOV",
  
          "start_time": "0.000000",
  
          "duration": "231.210000",
  
          "size": "65133325",
  
          "bit_rate": "2253650",
  
          "probe_score": 100,
  
          "tags": {
  
              "major_brand": "isom",
  
              "minor_version": "512",
  
              "compatible_brands": "isomiso2avc1mp41",
  
              "encoder": "Lavf55.33.100",
  
          }
  
      }
  
  }

  I’m wondering what does probe_score mean here ? How does it get calculated ?

• meaning of ffmpeg filter option values for modifying contrast/brightness/gamma

  5 septembre 2016, par benoy

  Context : I am using ffmpeg for processing a raw video file in raw y4m format to mp4 at various brightness values for an experiment looking at OLED display performance. After looking at the ffmpeg documentation I was able to find the following filter (eq) for modifying the brightness of the video.
  https://ffmpeg.org/ffmpeg-filters.html#eq

  I used the information from the ffmpeg documentation and the following article (https://wjwoodrow.wordpress.com/2015/07/12/more-ffmpeg-hell/) to get videos with different qualities. But neither the ffmpeg documentation nor the article explains these values in detail.

  Question : Now my query is that, what does these eq values range correspond to ? Is it a percentage ? For example,

  ffmpeg -i input_1080p24.y4m -vf eq=1:-0.5:1:1:1:1:1:1 -vcodec libx264 -b:v 8000k -s 1920x1080 -g 15 -n -r 30 output_1080p.mp4 

  gives me a output video with reduced brightness. But how do I quantify this brightness reduction ? Does this eq = -0.5 correspond to 50% reduction in original brightness ? In other words, is this a linear scale ?

  This is my first post on stackoverflow. Thanks !

• Power-Up your Matomo installation with Custom Reports

  13 novembre 2017, par InnoCraft — Plugins

  Would you like to create a report in Matomo (Piwik) with just the data you want and nothing else ? Would you like to be free to decide the shape of it ? Are you struggling with the Matomo database and wish you could have an easy interface to create the report you want ? Are you tired of exporting your data in a spreadsheet ? Since last October, there’s a solution and it’s called Custom Reports.

  With custom reports you will :

  1. get a user-friendly interface to create the report you wish
  2. see all the possible combinations to create the report you desire
  3. reveal new data combinations which were not directly available in Matomo (Piwik)

  User friendly interface

  The time when you created your reports from MySQL database is over. Now with custom reports you can create the report you want and get the data you need in just a few seconds.
  Custom reports are part of the main user interface. You can access them in just one click :

  

  As you can see from above the interface is straightforward, just indicate the name of your report and start to select the dimensions and metrics you would like to see.

  See all the possible combinations to create the report you desire

  As a user the big question has always been, how much data does Matomo (Piwik) collect and where can I find a list of all those data points ? Here you have the solution. Matomo is gathering in custom reports all the possible combinations so you can select only the data you want :

  

  Creating such a report is going to take you no more than a minute. As with any reports within Matomo (Piwik), you can easily get information regarding the specific data you are using by hovering your mouse on the question mark next to each dimension and metric :

  

  Make new combinations which were not directly available in Matomo

  By default, not all combinations are possible within the Matomo (Piwik) user interface. Now thanks to Custom Reports, you can easily design the report you want. Here is for example a report crossing page titles and page url :

  

  You can then identify if there are any duplicate titles within your content and see the associated URL in a single report.

  You could also identify easily what are your most viewed entry page from Google :

  

  Custom reports can also be used with segments and filters in order to get even more specific data.
  Here we have an example of a custom report designed to take into consideration only the visits coming from Wikipedia :

  

  What is the next step ?

  As you understood it, Matomo (Piwik) custom reports is the must-have plugin in order to take your Matomo to the next level. Why wait ? Matomo custom reports are available through the marketplace.

  Get Custom Reports

  If you are not sure yet, you can always give it a try within our Matomo Cloud (formerly Piwik Cloud) infrastructure.