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• mdec : stop preferring the simple IDCT.

  21 juin 2017, par Ronald S. Bultje

  mdec : stop preferring the simple IDCT.
  This was added in e3e3c82555e2382125195c1ba9f34b5a43299abc, probably
  
  as a workaround for the fact that the quant table was not permutated
  
  and the IDCT coefficients are, meaning that you'd only get correct
  
  reconstruction if the IDCT permutation was an identity matrix, which
  
  happens to be the case when you use the simple IDCT. The quant table
  
  permutation bug was fixed in 42dd1434bf6a7230e4175c08fcfabc3ba51a0463,
  
  meaning this workaround is no longer necessary.
  In practical terms, before 42dd1434bf6a7230e4175c08fcfabc3ba51a0463,
  
  the PSNR between decodes of the fate-mdec using simple (C) or simplemmx
  
  IDCTs was 35. After 42dd1434bf6a7230e4175c08fcfabc3ba51a0463, it's 90.
  

  • [DH] libavcodec/mdec.c

• 9 plugins you should definitely have heard of to prevent data leaks, security breaches and to get more flexibility in the way you log in to your Piwik.

  9 janvier 2017, par InnoCraft — Community

  At Piwik and at InnoCraft, we have always focussed on Security and take it very seriously. We were one of the first open source projects to offer a bug bounty for reporting security issues responsibly, Piwik has gone through several security audits and all changes in Piwik go through security reviews by our security experts.

  On the Piwik Marketplace you will find some plugins that give you just that extra bit of additional security to keep your data even more secure and to let you secure how your users log in to your Piwik.

  Security Info

  This plugin provides security information about the server(s) your Piwik is running on and offers suggestions on how to improve the security settings of your servers. We highly recommend to install the Security Info plugin. Checks performed include for example usage of the latest PHP version, usage of latest Piwik version, usage of PHP ini settings like magic_quotes_gpc and more. More details & download

  By Piwik

  Google Authenticator

  This plugins adds Two Factor Authentication, also known as 2FA, to Piwik. When logging in to Piwik, it forces you to confirm the identity by utilizing a combination of two different components. This means if someone knows your password, they will still need the other component in order to successfully log in, in this case a code that changes every minute on your phone. More details & download

  By Stefan Giehl

  Activity Log

  The plugin gives you a detailed audit log of all activities that happen in your Piwik for better security and problem diagnostic. It provides documentary evidence of over 80 different activities that happen in your Piwik and lets you for example see when someone successfully logged in, when someone tried to log in with your username, when someone deleted data, and much more. More details

  By InnoCraft, the makers of Piwik. Pricing starts from 39€ / $49 a year.

  Login Revokable

  This feature allows a user to log in from multiple locations (different browsers, computers, …) as usual and makes sure to log you out of all sessions as soon as you log out from any of these locations. More details & download

  By Bryan Torosian

  Force SSL

  For security and privacy reasons you should always use Piwik over HTTPS (SSL). By activating this plugin, you make sure to redirect all “http://” requests to “https://” in the Piwik UI and API. More details & download

  By InnoCraft, the makers of Piwik.

  Performance Info

  This plugin checks your Piwik configuration and compares it with some best practice settings. For example whether debug modes are disabled in a production environment, whether the example plugins that are shipped with Piwik are disabled, and more. Please note that this plugin works only with Piwik 2. More details & download

  By Martin Keckeis

  Login Ldap

  Some companies might already manage their users in an LDAP server. This plugin allows you to log in to your Piwik via a central LDAP and supports web server authentication (eg. for Kerberos SSO). It authenticates with an LDAP server and uses LDAP information to personalize Piwik. More details & download

  By Piwik

  Login Shibboleth

  Shibboleth is an open-source project that provides a Single Sign-On and allows websites to make informed authorization decisions in a privacy-preserving manner. Using this plugin allows you to connect to an existing Shibboleth environment so you need to manage users only once. More details & download

  By Universität Würzburg Rechenzentrum

  Login Http Auth

  This plugin allows you to sign in to your Piwik using the HTTP Auth protocol instead of the standard login mechanism. It extends the standard Piwik authentication to use Basic HTTP Authentication. This may be useful if you use Basic HTTP Authentication already anyway and don’t want to manage your users additionally in Piwik itself. We recommend to use this only over SSL, for example with the Force SSL plugin. More details & download

  By Piwik

  Custom Development

  Piwik is an analytics platform that you can extend and customize to your needs. Besides many configuration options you can change existing functionality and also build new functionality on top of Piwik, for example to log in to your Piwik via any Single-Sign-On. Read more about extending Piwik on the Piwik Developer Zone or get in touch with us and we take care of it for you.

• Python extract wav from video file

  10 janvier, par xolodec

  Related :

  



  How to extract audio from a video file using python ?

  



  Extract audio from video as wav

  



  How to rip the audio from a video ?

  



  My question is how could I extract wav audio track from video file, say video.avi ? 
I read many articles and everywhere people suggest to use (from Python) ffmpeg as a subprocess (because there are no reliable python bindings to ffmpeg - the only hope was PyFFmpeg but i found it is unmaintaned now). I don't know if it is right solution and i am looking for good one.
  
I looked to gstreamer and found it nice but unable to satisfy my needs — the only way I found to accomplish this from command line looks like

  



   gst-launch-0.10 playbin2 uri=file://`pwd`/ex.mp4  audio-sink='identity single-segment=true ! audioconvert ! audio/x-raw-int, endianness=(int)1234, signed=(boolean)true, width=(int)16, depth=(int)16, rate=(int)16000, channels=(int)1 ! wavenc !  filesink location=foo.wav’ 


  



  But it is not efficient because i need to wait ages while playing video and simultaneously writing to wav file.

  



  ffmpeg is much better :

  



  avconv  -i foo.mp4  -ab 160k -ac 1 -ar 16000 -vn ffaudio.wav


  



  But i am unable to launch it from python (not as a command line subprocess). Could you please point me out pros and cons of launching ffmpeg from python as a command line utility ? (I mean using python multiprocessing module or something similar).

  



  And second question.

  



  What is simple way to cut long wav file into pieces so that i don't break any words ? i mean pieces of 10-20 sec length with start and end during the pause in sentences/words ?

  



  i know how to break them on arbitrary pieces :

  



  import wave


win= wave.open('ffaudio.wav', 'rb')
wout= wave.open('ffsegment.wav', 'wb')

t0, t1= 2418, 2421 # cut audio between 2413, 2422 seconds
s0, s1= int(t0*win.getframerate()), int(t1*win.getframerate())
win.readframes(s0) # discard
frames= win.readframes(s1-s0)

wout.setparams(win.getparams())
wout.writeframes(frames)

win.close()
wout.close()