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• Piwik 3 Development Update #2 – Git master branch will become Piwik 3

  2 septembre 2016, par Piwik Core Team — Community, Development

  As mentioned in the Piwik 3 Development Update #1 we are actively working on the new major Piwik 3 release.

  This blog post is an announcement regarding an upcoming change on our Git repository.

  On October 4th CET, we will merge the current changes done for Piwik 3 from the “3.x-dev” branch into the “master“ branch across our Piwik projects and plugin repositories. While this is not important for most of our users, it can be a problem if you have installed and deployed Piwik from git.

  • If you are currently on “master” branch and want to continue using Piwik 2, you need to checkout the newly created “2.x-dev” branch instead of “master” anytime within the next 4 weeks. Don’t forget to update your scripts and scheduled tasks (cronjobs) that may reference “master” branch.
  • If you want to receive an early version of Piwik 3 via git automatically, you won’t have to change anything.

  The final Piwik 3 release will be ready before the end of the year. If you want to give it a try, you can either use Piwik from Git and check out the “3.x-dev” branch, or download Piwik 3 from GitHub.

  Until our next Piwik 3 dev update, Happy analysis !

• Programming Language Levels

  20 mai 2011, par Multimedia Mike — Programming

  I’ve been doing this programming thing for some 20 years now. Things sure do change. One change I ponder from time to time is the matter of programming language levels. Allow me to explain.

  The 1990s
  When I first took computer classes in the early 1990s, my texts would classify computer languages into 3 categories, or levels. The lower the level, the closer to the hardware ; the higher the level, the more abstract (and presumably, easier to use). I recall that the levels went something like this :

  • High level : Pascal, BASIC, Logo, Fortran
  • Medium level : C, Forth
  • Low level : Assembly language

  Keep in mind that these were the same texts which took the time to explain the history of computers from mainframes -> minicomputers -> a relatively recent phenomenon called microcomputers or "PCs".

  Somewhere in the mid-late 1990s, when I was at university, I was introduced to a new tier :

  • Very high level : Perl, shell scripting

  I think there was some debate among my peers about whether C++ and Java were properly classified as high or very high level. The distinction between high and very high, in my observation, seemed to be that very high level languages had more complex data structures (at the very least, a hash / dictionary / associative array / key-value map) built into the language, as well as implicit memory management.

  Modern Day
  These days, the old hierarchy is apparently forgotten (much like minicomputers). I observe that there is generally a much simpler 2-tier classification :

  • Low level : C, assembly language
  • High level : absolutely every other programming language in wide use today

  I find myself wondering where C++ and Objective-C fit in this classification scheme. Then I remember that it doesn’t matter and this is all academic.

  Relevancy
  I think about this because I have pretty much stuck to low-level programming all of my life, mostly due to my interest in game and multimedia-type programming. But the trends in computing have favored many higher level languages and programming paradigms. I woke up one day and realized that the kind of work I often do — lower level stuff — is not very common.

  I’m not here to argue that low or high level is superior. You know I’m all about using the appropriate tool for the job. But I sometimes find myself caught between worlds, having the defend and explain one to the other.

  • On one hand, it’s not unusual for the multitudes of programmers working at the high level to gasp and wonder why I or anyone else would ever use C or assembly language for anything when there are so many beautiful high level languages. I patiently explain that those languages have to be written in some other language (at first) and that they need to run on some operating system and that most assuredly won’t be written in a high level language. For further reading, I refer them to Joel Spolsky’s great essay called Back to Basics which describes why it can be useful to know at least a little bit about how the computer does what it does at the lowest levels.
  • On the other hand, believe it or not, I sometimes have to defend the merits of high level languages to my low level brethren. I’ll often hear variations of, "Any program can be written in C. Using a high level language to achieve the same will create a slow and bloated solution." I try to explain that the trade-off in time to complete the programming task weighed against the often-negligible performance hit of what is often an I/O-bound operation in the first place makes it worthwhile to use the high level language for a wide variety of tasks.

    Or I just ignore them. That’s actually the best strategy.

• ffmpeg cannot open a simple microsoft wav file exported with Audacity

  18 février 2014, par sebpiq

  I have exported a sound file to microsoft wav using Audacity.
  I am trying to open this file with ffmpeg :

  ffmpeg -i steps-stereo-16b-44khz.wav /tmp/test.ogg

  and here's the ouput I get :

  fmpeg version 1.2.1 Copyright (c) 2000-2013 the FFmpeg developers
  
    built on Jun 12 2013 13:46:11 with Apple clang version 4.1 (tags/Apple/clang-421.11.66) (based on LLVM 3.1svn)
  
    configuration: --prefix=/opt/local --enable-swscale --enable-avfilter --enable-libmp3lame --enable-libvorbis --enable-libopus --enable-libtheora --enable-libschroedinger --enable-libopenjpeg --enable-libmodplug --enable-libvpx --enable-libspeex --enable-libass --enable-libbluray --enable-gnutls --enable-libfreetype --mandir=/opt/local/share/man --enable-shared --enable-pthreads --cc=/usr/bin/clang --arch=x86_64 --enable-yasm --enable-gpl --enable-postproc --enable-libx264 --enable-libxvid
  
    libavutil      52. 18.100 / 52. 18.100
  
    libavcodec     54. 92.100 / 54. 92.100
  
    libavformat    54. 63.104 / 54. 63.104
  
    libavdevice    54.  3.103 / 54.  3.103
  
    libavfilter     3. 42.103 /  3. 42.103
  
    libswscale      2.  2.100 /  2.  2.100
  
    libswresample   0. 17.102 /  0. 17.102
  
    libpostproc    52.  2.100 / 52.  2.100
  
  [dca @ 0x7fd30c013600] Not a valid DCA frame
  
  
  
  ... SNIP ...
  
  
  
  [dca @ 0x7fd5bc013600] Invalid bit allocation index
  
  [dca @ 0x7fd5bc013600] error decoding block
  
      Last message repeated 3 times
  
  [dca @ 0x7fd5bc013600] Didn't get subframe DSYNC
  
  [dca @ 0x7fd5bc013600] error decoding block
  
  [wav @ 0x7fd5bc013000] max_analyze_duration 5000000 reached at 5009070 microseconds
  
  [wav @ 0x7fd5bc013000] decoding for stream 0 failed
  
  [wav @ 0x7fd5bc013000] Could not find codec parameters for stream 0 (Audio: dts ([1][0][0][0] / 0x0001), 192000 Hz, 2 channels, fltp, 0 kb/s): no decodable DTS frames
  
  Consider increasing the value for the 'analyzeduration' and 'probesize' options
  
  steps-stereo-16b-44khz.wav: could not find codec parameters

  If I export the same file to .ogg or .aiff, no problem, the following works fine :

  ffmpeg -i steps-stereo-16b-44khz.aiff /tmp/test.ogg

  Any idea what could be wrong ?

  A link to my wav file so you can try to reproduce.

  NB my final goal is to slice the audio file. I know I can export file directly to .ogg with audacity. This is just a test case.

  EDIT

  Getting file info with another program like sox, works well :

  sox --info steps-stereo-16b-44khz.wav
  
  
  
  Input File     : 'steps-stereo-16b-44khz.wav'
  
  Channels       : 2
  
  Sample Rate    : 44100
  
  Precision      : 16-bit
  
  Duration       : 00:00:02.10 = 92608 samples = 157.497 CDDA sectors
  
  File Size      : 370k
  
  Bit Rate       : 1.41M
  
  Sample Encoding: 16-bit Signed Integer PCM