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• Piwik is expanding ! We’re seeking a talented Software Engineer in New Zealand or in Poland

  13 mai 2014, par Matthieu Aubry — About, Community

  At Piwik and Piwik PRO we develop the leading open source web analytics platform, used by more than one million websites worldwide. Our vision is to build the best open alternative to Google Universal Analytics.

  The Piwik platform collects, stores and processes a lot of information : hundreds of millions of data points each month. We create intuitive, simple and beautiful reports that delight our users.

  Are you seeking a new challenge ? We are currently looking for a software engineer or software developer who is passionate about data processing, security, privacy, the open source philosophy and usable interface design.

  We practise agile methodology, test driven development, and fast release cycles. The main technologies we work with are Javascript (AngularJS, jquery), PHP5 and MySQL. You will write open source code that will directly benefit 250,000+ Piwik users in more than 200 countries and 50 languages.

  Responsibilities

  • Write server-side code (PHP5) and front-end code (Javascript) for Piwik platform.
  • Create robust high-volume production applications and develop prototypes quickly.
  • Tackle new problems as we continue to push technology forward.

  Minimum qualifications

  • BA/BS degree in Computer Science or equivalent practical experience.
  • 2 years of relevant work experience in software development.
  • Understanding of, and practical experience with PHP5 and Javascript application development.
  • Strong analytical and coding skills.
  • Excellent communication skills.

  Location

  • Wellington central, New Zealand.
    If you are not in New Zealand, and you are the right candidate, we will help you relocate here !
  • Wrocław, Poland

  Apply online

  To apply for this position, please Apply online here. We look forward to receiving your applications !

• Piwik is expanding ! We’re seeking a talented Software Engineer in New Zealand or in Poland

  13 mai 2014, par Matthieu Aubry — About, Community

  At Piwik and Piwik PRO we develop the leading open source web analytics platform, used by more than one million websites worldwide. Our vision is to build the best open alternative to Google Universal Analytics.

  The Piwik platform collects, stores and processes a lot of information : hundreds of millions of data points each month. We create intuitive, simple and beautiful reports that delight our users.

  Are you seeking a new challenge ? We are currently looking for a software engineer or software developer who is passionate about data processing, security, privacy, the open source philosophy and usable interface design.

  We practise agile methodology, test driven development, and fast release cycles. The main technologies we work with are Javascript (AngularJS, jquery), PHP5 and MySQL. You will write open source code that will directly benefit 250,000+ Piwik users in more than 200 countries and 50 languages.

  Responsibilities

  • Write server-side code (PHP5) and front-end code (Javascript) for Piwik platform.
  • Create robust high-volume production applications and develop prototypes quickly.
  • Tackle new problems as we continue to push technology forward.

  Minimum qualifications

  • BA/BS degree in Computer Science or equivalent practical experience.
  • 2 years of relevant work experience in software development.
  • Understanding of, and practical experience with PHP5 and Javascript application development.
  • Strong analytical and coding skills.
  • Excellent communication skills.

  Location

  • Wellington central, New Zealand.
    If you are not in New Zealand, and you are the right candidate, we will help you relocate here !
  • Wrocław, Poland

  Apply online

  To apply for this position, please Apply online here. We look forward to receiving your applications !

• FFMpeg - increase processing speed for filter_complex with enable='0' ?

  16 août 2021, par Giorgio F

  I am running a FFmpeg command with 'filter_complex', applying a set of consecutive filters, that ultimately will only be applied to some specific frames.

  


  The challenge I'm having is the command performance - regardless of applying the filter to all frames or not, the performance is very similar.

  


  Here are some examples :

  


  

  1. Apply a filter to every frame (alternate between 2 different filters, every 15 frames) :

  


  


  ffmpeg -y -i video.mp4 -i "image1.png" -i "image2.png" -filter_complex "[0:v]format=gbrp[f],[0:v]format=gbrp[f1],[0:v]format=gbrp[f2],[1:v]format=gbrp[w1],[2:v]format=gbrp[w2],[f1][w1]blend=all_mode='darken':enable='lt(mod(n\,30)\,15)'[fw1];[f2][w2]blend=all_mode='lighten':enable='gte(mod(n\,30)\,15)'[fw2];[f][fw1]blend=all_mode='lighten':enable='lt(mod(n\,30)\,15)'[ftmp];[ftmp][fw2]blend=all_mode='darken':enable='gte(mod(n\,30)\,15)'" output.mp4


  


  Processing speed=0.625x

  


  

  2. Apply the filter every 15 frames (2 filters alternating every 30 frames) :

  


  


  ffmpeg -y -i video.mp4 -i "image1.png" -i "image2.png" -filter_complex "[0:v]format=gbrp[f],[0:v]format=gbrp[f1],[0:v]format=gbrp[f2],[1:v]format=gbrp[w1],[2:v]format=gbrp[w2],[f1][w1]blend=all_mode='darken':enable='eq(mod(n\,30)\,15)'[fw1];[f2][w2]blend=all_mode='lighten':enable='eq(mod(n\,30)\,15)'[fw2];[f][fw1]blend=all_mode='lighten':enable='eq(mod(n\,30)\,15)'[ftmp];[ftmp][fw2]blend=all_mode='darken':enable='eq(mod(n\,30)\,15)'" output.mp4


  


  Processing speed=0.661x

  


  

  3. Set all "enabled" properties to 0 (therefore not applying any filter at all) :

  


  


  ffmpeg -y -i video.mp4 -i "image1.png" -i "image2.png" -filter_complex "[0:v]format=gbrp[f],[0:v]format=gbrp[f1],[0:v]format=gbrp[f2],[1:v]format=gbrp[w1],[2:v]format=gbrp[w2],[f1][w1]blend=all_mode='darken':enable='0'[fw1];[f2][w2]blend=all_mode='lighten':enable='0'[fw2];[f][fw1]blend=all_mode='lighten':enable='0'[ftmp];[ftmp][fw2]blend=all_mode='darken':enable='0'" output.mp4


  


  Processing speed=0.663x

  


  

  4. Apply a basic "Negate" filter to the video :

  


  


  ffmpeg -y -i video.mp4 -i "image1.png" -i "image2.png" -filter_complex "[0:v]format=gbrp[f],[f]negate" output.mp4


  


  Processing speed=1.23x

  


  
The performance is very similar for the cases 1. to 3., however I was expecting a similar performance between the two last ones since, in theory, nothing is processed on the 3. - however, with every filter turned off, the performance is very similar to having all filters enabled.

  


  Is there any way I am able to rewrite this command in order to increase the performance ?
The final goal will is to increase the performance for the case 2.

  


  Thanks in advance !