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• Video Seek Scroll (60FPS)

  9 avril 2022, par Enijar

  Trying to achieve an effect of seeking through a video when the page is scrolled. This has been achieved by exporting all frames of the video to JPEG images, pre-loading the images, and rendering them to a canvas. However, this approach uses a lot of bandwidth and takes a long time to load on slow networks.

  


  Trying to achieve the same effect by rendering a video to a canvas does not play as smoothly as the image-based approach.

  


  Here is a working demo with the video-based approach :

  


  https://codesandbox.io/s/infallible-chaum-grvi0r?file=/index.html

  


  Since HTMLMediaElement.fastSeek() doesn't have widespread browser coverage, how can one achieve a realtime playback rate of 30-60 FPS ?

  


  Here is the relevant code for the effect (see CSB link above for the full code) :

  


  const video = document.querySelector("video");
const canvas = document.querySelector("canvas");
const ctx = canvas.getContext("2d");

(function tick() {
  requestAnimationFrame(tick);

  const { scrollHeight, clientHeight, scrollTop } = document.body;
  const maxScroll = scrollHeight - clientHeight;
  const scrollProgress = scrollTop / maxScroll;

  canvas.width = document.body.clientWidth;
  canvas.height = document.body.clientHeight;

  // This is the line that causes the issue
  video.currentTime = video.duration * scrollProgress;

  ctx.clearRect(0, 0, canvas.width, canvas.height);
  ctx.drawImage(video, 0, 0, canvas.width, canvas.height);
})();


  


• ffmpeg - preserve metadata for the converted files (mtime)

  5 mars 2017, par silent

  I have a simple batch file that converts videos from mobile. I want to keep the original creation and modification time in converted files as well.

  For example, I have :

  
  
  
  name
  creation time
  modification time
  
  file.mp4
  21 March 2016
  21 March 2016
  
  

  after conversion I have :

  
  
  
  name
  creation time
  modification time
  
  file_new.mp4
  05 March 2017
  05 March 2017
  
  

  but all I want is :

  
  
  
  name
  creation time
  modification time
  
  file_new.mp4
  21 March 2016
  21 March 2016
  
  

  My ffmpeg command (Windows) :

  for %%a in ("*.mp4") do ffmpeg -i "%%a" -c:v libx264 -crf 23 -preset medium -map_metadata 0 -movflags +faststart -c:a libvo_aacenc -b:a 96k "newfiles\%%~na.mp4"

• Piwik 2.1 — Massive Performance and Reliability Improvements

  4 mars 2014, par Benaka M. — Community, Development

  We are very excited to announce the immediate availability of Piwik v2.1.0 !

  • Download Link
  • How to update Piwik ?
  • List of all tickets closed : Changelog

  Piwik 2.1 is the first release after our 2.0 release and it reflects the new direction Piwik is moving in : better performance, more reliability and a better overall open platform ! We also released more plugins on the marketplace as well as helped developers build exciting new plugins for Piwik.

  This 2.1.0 release contains several performance and reliability improvements to the archiving process and to the new device detection process introduced in Piwik 2.0. It also includes a new email report format (CSV), a new marketplace plugin and overall more than 80 improvements (source).

  Massive Performance Improvements to Archiving

  The biggest improvement this release brings to Piwik are the various performance improvements made to the Archiving Process. These improvements include the following :

  • The amount of memory used has been reduced in some cases by 80% or more ! What used to require 8GB of memory will now only require 1GB. Piwik engineers analysed Profiler XHProf reports of Piwik under high load and implemented several improvements to archiving.
  • The cron script you can setup to automatically process your reports will now create new processes to perform asynchronous archiving instead issuing CURL http requests. This change results in increases to the performance and reliability of the Archiving Process.

  Bug Fixes and Performance Improvements to Device Detection

  In Piwik 1.12 we introduced a new device detection feature that could detect much more information than what we used before. Piwik 2.1 includes several bug fixes and improvements to this feature (such as detecting dozens of new devices, brands and models for smartphones, tablets and other devices). To use this feature, go to “Settings” then “Plugins” then activate the DevicesDetection plugin.

  New Default MySQL Database Type (InnoDB)

  This change doesn’t affect our existing Piwik users, but it does reflect our commitment to performance and reliability. We’ve changed the default MySQL database type to be InnoDB instead of Myisam. This will allow new users to immediately gain the benefits in reliability offered by InnoDB.

  New Marketplace Plugin – HTTP Authentication

  We’re releasing a new plugin on the marketplace that will allow you to use the HTTP authentication services provided by your webserver. Learn more about this plugin on the marketplace.

  New Email Format for Scheduled Reports

  The last big change in this release is a new email report format. You can now get your email reports as CSV files as well as HTML and PDF reports.

  Other Improvements

  In addition to performance improvements and new plugins, this release contains a few other smaller improvements described below.

  Changing segments in the Embedded Dashboard

  The embedded dashboard is the powerful feature that lets you include the Piwik Dashboard without the top menu and Piwik branding, directly within your application !

  This dashboard will now include the segment selector allowing you to change the current segment and create new segments, just as you would in the normal dashboard view :

  

  Multiple Super Users

  It’s now possible for your Piwik to have more than one Super User and for Super Users to have aliases :

  

  Learn more in the User guide : Managing Super Users in Piwik.

  Smart App Banners for our Mobile Apps

  Finally, in accord with our commitment to providing great User Experience, we’ve added a smart banner to Piwik so users that view Piwik from a mobile device will be informed of our amazing (and free !) mobile apps (for both iOS and Android).

  Participate in Piwik

  Are you a talented developer or an experienced User Interface designer ? If you have some free time and if you want to contribute to one of the most awesome open source projects around, please get in touch with the Piwik team, or read this page to learn more ?

  Summary

  For the full list of changes in Piwik 2.1 check out the Changelog.

  Thank you to the core developers, all the beta testers and users, our official supporters, the translators & everyone who reported bugs or feature requests. Also thank you to the software we use, and the libraries we use.

  Many of the improvements in this release come from the efforts of Piwik PRO experts. If you are looking for help to make the most of your analytics data, contact Piwik PRO. Learn more about us here.

  If you like what you read, please tell your friends and colleagues or write on your website, blog, forums, stackoverflow, etc.

  Enjoy !