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• Catalyst Open Source Academy

  16 janvier 2015, par Matthieu Aubry — Community

  The Open Source Academy is an initiative designed to provide training and work experience for young New Zealand technologists. Catalyst organises the Academy to show young technologists how to participate in open source communities and to fully explore their passion for IT through freely available open source tools.

  It has been running annually since 2011. We are proud that Piwik project could participate in the Academy again this year !

  What students got done

  It’s amazing what a few young students can get done in four days of participating in an open source project like Piwik ! They were able to quickly get started with Piwik, and continued to make useful contributions to the Piwik analytics platform.

  New Darkness theme

  Liam has created a new dark theme for Piwik called Darkness.

  

  To create the theme, Liam had to improve Piwik core stylesheets and created this pull request : Reuse the LESS variable for white color across all stylesheets.

  Accessibility improvements

  We were lucky to spend time with Julius, a Catalyst employee who is blind. He showed us in great detail how difficult and time consuming it can be for a blind user to use Piwik. For example we noticed how complicated it was for Julius to navigate the menus, to get to the main content, and to use the calendar and the Website selector. During this presentation we also noticed that Piwik was not yet usable with the keyboard.

  As a result of this session with Julius we got to work with the students to improve accessibility in Piwik.

  

  (photo source)

  List of accessibility improvements

  All these pull requests were created by the students and have been successfully merged into Piwik :

  • see the focus of menu items when tabbing through the page
  • Tweaks to improve accessibility (section around graph, better tooltip, set language in html)
  • Added h3 tags to widget headers
  • when main Menu is focused, display submenu
  • Add “Skip to content” feature when user presses tab key
  • Improved accessibility by putting offscreen text in the widget title

  To learn more about accessibility in Piwik check out this issue on our tracker.

  Summary

  Working with young students was fun and interesting. We were excited to see how much they got done in such a short time !

  At Piwik and Piwik PRO we are committed to building the best open analytics platform, and we will continue to support students who want to take part in the Piwik adventure.

  Be well,

• FFMPEG gets stuck on higher resolution or frame rate [H265]

  29 octobre 2015, par Anakooter

  I am running the following command which works perfectly on my system running Elementary OS on Intel Corei5 :

  ffmpeg -f v4l2 -i /dev/video0 -c:v libx265 -x265-params crf=14:vbv-maxrate=128:vbv-bufsize=32:keyint=10:qcomp=0.5:rd=5:ctu=64:min-cu-size=8:cu-lossless=false:fast-intra=false:strong-intra-smoothing=false -tune zerolatency -s 640x480 -preset ultrafast -r 5 -pix_fmt yuv420p -an -strict experimental -f mpegts udp://239.0.0.1:5002

  but if I change the output size to 800x600 and or increase the frame rate from 5 to 10. After a few seconds the video gets stuck.

  I have monitored the CPU usage for both the commands and it is almost identical that is between 300 to 400 percent ( since 4 cores ).

  Any possible answers to mitigate the issue.

  ffmpeg version 2.7.2-static http://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2015 the FFmpeg developers
  
  built with gcc 4.9.3 (Debian 4.9.3-1)
  
  configuration: --enable-gpl --enable-version3 --disable-shared --disable-debug --enable-runtime-cpudetect --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-libwebp --enable-libspeex --enable-libvorbis --enable-libvpx --enable-libfreetype --enable-fontconfig --enable-libxvid --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus --enable-libass --enable-gnutls --enable-libvidstab --enable-libsoxr --cc=gcc-4.9
  
  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
  
  Routing option strict to both codec and muxer layer
  
  [video4linux2,v4l2 @ 0x4775460] fd:4 capabilities:84000001
  
  Input #0, video4linux2,v4l2, from '/dev/video0':
  
  Duration: N/A, start: 1223.904801, bitrate: 36864 kb/s
  
  Stream #0:0: Video: rawvideo, 1 reference frame (YUY2 / 0x32595559), yuyv422, 320x240, 36864 kb/s, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
  
  [graph 0 input from stream 0:0 @ 0x476aae0] w:320 h:240 pixfmt:yuyv422     tb:1/1000000 fr:30/1 sar:0/1 sws_param:flags=2
  
  [scaler for output stream 0:0 @ 0x476a920] w:800 h:600 flags:'0x4' interl:0
  
  [scaler for output stream 0:0 @ 0x476a920] w:320 h:240 fmt:yuyv422 sar:0/1 -> w:800 h:600 fmt:yuv420p sar:0/1 flags:0x4
  
  x265 [info]: HEVC encoder version 1.7+354-b2ba7df1fc69
  
  x265 [info]: build info [Linux][GCC 4.9.3][64 bit] 8bit
  
  x265 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
  
  x265 [info]: Main profile, Level-3 (Main tier)
  
  x265 [info]: Thread pool created using 4 threads
  
  x265 [info]: frame threads / pool features       : 2 / wpp(10 rows)
  
  x265 [info]: Coding QT: max CU size, min CU size : 64 / 8
  
  x265 [info]: Residual QT: max TU size, max depth : 32 / 1 inter / 1 intra
  
  x265 [info]: ME / range / subpel / merge         : dia / 57 / 0 / 2
  
  x265 [info]: Keyframe min / max / scenecut       : 1 / 10 / 0
  
  x265 [info]: Lookahead / bframes / badapt        : 0 / 0 / 0
  
  x265 [info]: b-pyramid / weightp / weightb       : 0 / 0 / 0
  
  x265 [info]: References / ref-limit  cu / depth  : 1 / 0 / 0
  
  x265 [info]: Rate Control / qCompress            : CRF-14.0 / 0.50
  
  x265 [info]: VBV/HRD buffer / max-rate / init    : 32 / 64 / 0.900
  
  x265 [info]: tools: rd=5 psy-rd=0.30 early-skip tmvp deblock
  
  [mpegts @ 0x4776b00] muxrate VBR, pcr every 1 pkts, sdt every 200, pat/pmt every 40 pkts
  
  Output #0, mpegts, to 'udp://239.0.0.1:5002':
  
  Metadata:
  
  encoder         : Lavf56.36.100
  
  Stream #0:0: Video: hevc (libx265), 1 reference frame, yuv420p, 800x600, q=2-31, 10 fps, 90k tbn, 10 tbc
  
  Metadata:
  
  encoder         : Lavc56.41.100 libx265
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> hevc (libx265))
  
  Press [q] to stop, [?] for help
  
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• My journey to Coviu

  27 octobre 2015, par silvia

  My new startup just released our MVP – this is the story of what got me here.

  I love creating new applications that let people do their work better or in a manner that wasn’t possible before.

  My first such passion was as a student intern when I built a system for a building and loan association’s monthly customer magazine. The group I worked with was managing their advertiser contacts through a set of paper cards and I wrote a dBase based system (yes, that long ago) that would manage their customer relationships. They loved it – until it got replaced by an SAP system that cost 100 times what I cost them, had really poor UX, and only gave them half the functionality. It was a corporate system with ongoing support, which made all the difference to them.

  The story repeated itself with a CRM for my Uncle’s construction company, and with a resume and quotation management system for Accenture right after Uni, both of which I left behind when I decided to go into research.

  Even as a PhD student, I never lost sight of challenges that people were facing and wanted to develop technology to overcome problems. The aim of my PhD thesis was to prepare for the oncoming onslaught of audio and video on the Internet (yes, this was 1994 !) by developing algorithms to automatically extract and locate information in such files, which would enable users to structure, index and search such content.

  Many of the use cases that we explored are now part of products or continue to be challenges : finding music that matches your preferences, identifying music or video pieces e.g. to count ads on the radio or to mark copyright infringement, or the automated creation of video summaries such as trailers.

  

  This continued when I joined the CSIRO in Australia – I was working on segmenting speech into words or talk spurts since that would simplify captioning & subtitling, and on MPEG-7 which was a (slightly over-engineered) standard to structure metadata about audio and video.

  In 2001 I had the idea of replicating the Web for videos : i.e. creating hyperlinked and searchable video-only experiences. We called it “Annodex” for annotated and indexed video and it needed full-screen hyperlinked video in browsers – man were we ahead of our time ! It was my first step into standards, got several IETF RFCs to my name, and started my involvement with open codecs through Xiph.

  Around the time that YouTube was founded in 2006, I founded Vquence – originally a video search company for the Web, but pivoted to a video metadata mining company. Vquence still exists and continues to sell its data to channel partners, but it lacks the user impact that has always driven my work.

  As the video element started being developed for HTML5, I had to get involved. I contributed many use cases to the W3C, became a co-editor of the HTML5 spec and focused on video captioning with WebVTT while contracting to Mozilla and later to Google. We made huge progress and today the technology exists to publish video on the Web with captions, making the Web more inclusive for everybody. I contributed code to YouTube and Google Chrome, but was keen to make a bigger impact again.

  The opportunity came when a couple of former CSIRO colleagues who now worked for NICTA approached me to get me interested in addressing new use cases for video conferencing in the context of WebRTC. We worked on a kiosk-style solution to service delivery for large service organisations, particularly targeting government. The emerging WebRTC standard posed many technical challenges that we addressed by building rtc.io , by contributing to the standards, and registering bugs on the browsers.

  Fast-forward through the development of a few further custom solutions for customers in health and education and we are starting to see patterns of need emerge. The core learning that we’ve come away with is that to get things done, you have to go beyond “talking heads” in a video call. It’s not just about seeing the other person, but much more about having a shared view of the things that need to be worked on and a shared way of interacting with them. Also, we learnt that the things that are being worked on are quite varied and may include multiple input cameras, digital documents, Web pages, applications, device data, controls, forms.

  So we set out to build a solution that would enable productive remote collaboration to take place. It would need to provide an excellent user experience, it would need to be simple to work with, provide for the standard use cases out of the box, yet be architected to be extensible for specialised data sharing needs that we knew some of our customers had. It would need to be usable directly on Coviu.com, but also able to integrate with specialised applications that some of our customers were already using, such as the applications that they spend most of their time in (CRMs, practice management systems, learning management systems, team chat systems). It would need to require our customers to sign up, yet their clients to join a call without sign-up.

  Collaboration is a big problem. People are continuing to get more comfortable with technology and are less and less inclined to travel distances just to get a service done. In a country as large as Australia, where 12% of the population lives in rural and remote areas, people may not even be able to travel distances, particularly to receive or provide recurring or specialised services, or to achieve work/life balance. To make the world a global village, we need to be able to work together better remotely.

  The need for collaboration is being recognised by specialised Web applications already, such as the LiveShare feature of Invision for Designers, Codassium for pair programming, or the recently announced Dropbox Paper. Few go all the way to video – WebRTC is still regarded as a complicated feature to support.

  

  With Coviu, we’d like to offer a collaboration feature to every Web app. We now have a Web app that provides a modern and beautifully designed collaboration interface. To enable other Web apps to integrate it, we are now developing an API. Integration may entail customisation of the data sharing part of Coviu – something Coviu has been designed for. How to replicate the data and keep it consistent when people collaborate remotely – that is where Coviu makes a difference.

  We have started our journey and have just launched free signup to the Coviu base product, which allows individuals to own their own “room” (i.e. a fixed URL) in which to collaborate with others. A huge shout out goes to everyone in the Coviu team – a pretty amazing group of people – who have turned the app from an idea to reality. You are all awesome !

  With Coviu you can share and annotate :

  • images (show your mum photos of your last holidays, or get feedback on an architecture diagram from a customer),
  • pdf files (give a presentation remotely, or walk a customer through a contract),
  • whiteboards (brainstorm with a colleague), and
  • share an application window (watch a YouTube video together, or work through your task list with your colleagues).

  All of these are regarded as “shared documents” in Coviu and thus have zooming and annotations features and are listed in a document tray for ease of navigation.

  This is just the beginning of how we want to make working together online more productive. Give it a go and let us know what you think.

  http://coviu.com/