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• Help us Reset The Net today on June 5th

  5 juin 2014, par Piwik Core Team — Community, Meta

  This blog post explains why the Piwik project is joining ResetTheNet online protest and how you can help make a difference against mass surveillance. It also includes an infographic and links to useful resources which may be of interest to you.

  Snowden revelations, a year ago today

  On June 5, 2013 the Guardian newspaper published the first of Edward Snowden’s astounding revelations. It was the first of a continuous stream of stories that pointed out what we’ve suspected for a long time : that the world’s digital communications are being continuously spied upon by nation states with precious little oversight.

  Unfortunately, mass surveillance is affecting the internet heavily. The Internet is a powerful force that can promote democracy, innovation, and creativity, but it’s being subverted as a tool for government spying. That is why Piwik has decided to join Reset The Net.

  June 5, 2014 marks a new year : a year that will not just be about listening to the inside story of mass surveillance, but a new year of fighting back !

  How do I protect myself and others ?

  Reset the Net is asking everyone to help by installing free software tools that are designed to protect your privacy on a computer or a mobile device.

  Reset the Net is also calling on websites and developers to add surveillance resistant features such as HTTPS and forward secrecy.

  Participate in ResetTheNet online protest

  Have you got your own website, blog or tumblr ? Maybe you can show the Internet Defense League’s “Cat Signal !” on your website.Get the code now to run the Reset the Net splash screen or banner to help make privacy viral on June 5th.

  Message from Edward Snowden

  Evan from FFTF sent us this message from Edward Snowden and we thought we would share it with you :

  One year ago, we learned that the internet is under surveillance, and our activities are being monitored to create permanent records of our private lives — no matter how innocent or ordinary those lives might be.

  Today, we can begin the work of effectively shutting down the collection of our online communications, even if the US Congress fails to do the same. That’s why I’m asking you to join me on June 5th for Reset the Net, when people and companies all over the world will come together to implement the technological solutions that can put an end to the mass surveillance programs of any government. This is the beginning of a moment where we the people begin to protect our universal human rights with the laws of nature rather than the laws of nations.

  We have the technology, and adopting encryption is the first effective step that everyone can take to end mass surveillance. That’s why I am excited for Reset the Net — it will mark the moment when we turn political expression into practical action, and protect ourselves on a large scale.

  Join us on June 5th, and don’t ask for your privacy. Take it back.

  – Message by Edward Snowden

  ResetTheNet privacy pack infographic

  

  Additional Resources

  Configure Piwik for Security and Privacy

  • Turn on automatic SSL redirection in your Piwik.
  • Configure Piwik for advanced Privacy.
  • Best security practises for Piwik.

  More info

  • Learn why this matters (EFF)
  • Data Privacy Day – Why is privacy important ? (Piwik)
  • Web Analytics Privacy (Piwik)

• Revisiting the Belco Alpha-400

  26 août 2010, par Multimedia Mike — General

  Relieved of the primary FATE maintenance duties, I decided to dust off my MIPS-based Belco Alpha-400 and try to get it doing FATE cycles. And just as I was about to get FATE running, I saw that Mans already got his MIPS-based Popcorn Hour device to run FATE. But here are my notes anyway.

  
  
  

  Getting A Prompt
  For my own benefit, I made a PDF to remind me precisely how to get a root prompt on the Alpha-400. The ‘jailbreak’ expression seems a little juvenile to me, but it seems to be in vogue right now.

  alpha-400-jailbreak.pdf

  Toolchain
  When I last tinkered with the Alpha-400, I was trying to build a toolchain that could build binaries to run on the unit’s MIPS chip, to no avail. Sometime last year, MichaelK put together x86_32-hosted toolchains that are able to build mipsel 32-bit binaries for Linux 2.4 and 2.6. The Alpha-400 uses a 2.4 kernel and the corresponding toolchain works famously for building current FFmpeg (--disable-devices is necessary for building).

  FATE Samples
  Next problem : Making the FATE suite available to the Alpha-400. I copied all of the FATE suite samples onto a VFAT-formatted SD card. The filename case is not preserved for all files which confounds me since it is preserved in other cases. I tried formatting the card for ext3 but the Alpha-400 would not mount it, even though /proc/filesystems lists ext3 (supporting an older version of ext3 ?).

  Alternative : Copy all of the FATE samples to the device’s rootfs. Space will be a little tight, though. Then again, there is over 600 MB of space free ; I misread earlier and thought there were only 300 MB free.

  Remote Execution
  To perform FATE cycles on a remote device, it helps to be able to SSH into that remote device. I don’t even want to know how complicated it would be to build OpenSSH for the device. However, the last time I brought up this topic, I learned about a lighter weight SSH replacement called Dropbear. It turns out that Dropbear runs great on this MIPS computer.

  Running FATE Remotely
  I thought all the pieces would be in place to run FATE at this point. However, there is one more issue : Running FATE on a remote system requires that the host and the target are sharing a filesystem somehow. My personal favorite remote filesystem method is sshfs which is supposed to work wherever there is an SSH server. That’s not entirely true, though– sshfs also requires sftp-server to be installed on the server side, a program that Dropbear does not currently provide.

  I’m not even going to think about getting Samba or NFS server software installed on the Alpha-400. According to the unit’s /proc/filesystems file, nfs is a supported filesystem. I hate setting up NFS but may see if I can get that working anyway.

  Residual Weirdness
  The unit comes with the venerable Busybox program (BusyBox v1.4.1 (2007-06-01 20:37:18 CST) multi-call binary) for most of its standard command line utilities. I noticed a quirk where BusyBox’s md5sum gives weird hex characters. This might be a known/fixed issue.

  Another item is that the Alpha-400′s /dev/null file only has rwxr-xr-x per default. This caused trouble when I first tried to scp using Dropbear using a newly-created, unprivileged user.

• FFmpeg zoompan filter always arcs when panning — how to get a straight‐line pan to a focus rectangle center ?

  26 mai, par Mykyta Manuilenko

  I’m trying to generate a 10s video from a single PNG image with FFmpeg’s zoompan filter, where the crop window zooms in from the image center and simultaneously pans in a perfectly straight line to the center of a predefined focus rectangle.

  


  My input parameters :

  


  "zoompan": {
  "timings": {
    "entry": 0.5, // show full frame
    "zoom": 1, // zoom-in/zoom-out timing
    "outro": 0.5 // show full frame in the end
  },
  "focusRect": {
    "x": 1086.36,
    "y": 641.87,
    "width": 612.44,
    "height": 344.86
  }
}


  


  My input/output values :

  


  

  • fps : 25

  


  • image input dimensions : 1920 × 1080

  


  • output video dimensions : 1920 × 1080

  


  


  My calculations :

  


      // Width of the bounding box to zoom into
    const bboxWidth = focusRect.width;

    // Height of the bounding box to zoom into
    const bboxHeight = focusRect.height;

    // X coordinate (center of the bounding box)
    const bboxX = focusRect.x + focusRect.width / 2;

    // Y coordinate (center of the bounding box)
    const bboxY = focusRect.y + focusRect.height / 2;

    // Time (in seconds) to wait before starting the zoom-in
    const preWaitSec = timings.entry;

    // Duration (in seconds) of the zoom-in/out animation
    const zoomSec = timings.zoom;

    // Time (in seconds) to wait on the last frame after zoom-out
    const postWaitSec = timings.outro;

    // Frame counts
    const preWaitF = Math.round(preWaitSec * fps);
    const zoomInF = Math.round(zoomSec * fps);
    const zoomOutF = Math.round(zoomSec * fps);
    const postWaitF = Math.round(postWaitSec * fps);

    // Calculate total frames and holdF
    const totalF = Math.round(duration * fps);

    // Zoom target so that bbox fills the output
    const zoomTarget = Math.max(
      inputWidth / bboxWidth,
      inputHeight / bboxHeight,
    );

    // Calculate when zoom-out should start (totalF - zoomOutF - postWaitF)
    const zoomOutStartF = totalF - zoomOutF - postWaitF;

    // Zoom expression (simple linear in/out)
    const zoomExpr = [
      // Pre-wait (hold at 1)
      `if(lte(on,${preWaitF}),1,`,
      // Zoom in (linear)
      `if(lte(on,${preWaitF + zoomInF}),1+(${zoomTarget}-1)*((on-${preWaitF})/${zoomInF}),`,
      // Hold zoomed
      `if(lte(on,${zoomOutStartF}),${zoomTarget},`,
      // Zoom out (linear)
      `if(lte(on,${zoomOutStartF + zoomOutF}),${zoomTarget}-((${zoomTarget}-1)*((on-${zoomOutStartF})/${zoomOutF})),`,
      // End
      `1))))`,
    ].join('');

    // Center bbox for any zoom
    const xExpr = `${bboxX} - (${outputWidth}/zoom)/2`;
    const yExpr = `${bboxY} - (${outputHeight}/zoom)/2`;

    // Build the filter string
    const zoomPanFilter = [
      `zoompan=`,
      `s=${outputWidth}x${outputHeight}`,
      `:fps=${fps}`,
      `:d=${totalF}`,
      `:z='${zoomExpr}'`,
      `:x='${xExpr}'`,
      `:y='${yExpr}'`,
      `,gblur=sigma=0.5`,
      `,minterpolate=mi_mode=mci:mc_mode=aobmc:vsbmc=1:fps=${fps}`,
    ].join('');


  


  So, my FFmpeg command looks like :

  


  ffmpeg -t 10 -framerate 25 -loop 1 -i input.png -y -filter_complex "[0:v]zoompan=s=1920x1080:fps=25:d=250:z='if(lte(on,13),1,if(lte(on,38),1+(3.1350009796878058-1)*((on-13)/25),if(lte(on,212),3.1350009796878058,if(lte(on,237),3.1350009796878058-((3.1350009796878058-1)*((on-212)/25)),1))))':x='1392.58 - (1920/zoom)/2':y='814.3 - (1080/zoom)/2',gblur=sigma=0.5,minterpolate=mi_mode=mci:mc_mode=aobmc:vsbmc=1:fps=25,format=yuv420p,pad=ceil(iw/2)*2:ceil(ih/2)*2" -vcodec libx264 -f mp4 -t 10 -an -crf 23 -preset medium -copyts output.mp4


  


  Actual behavior :

  


  The pan starts at the image center, but follows a curved (arc-like) trajectory before it settles on the focus‐rect center (first it goes to the right bottom corner and then to the focus‐rect center).

  


  Expected behavior :

  


  The pan should move the crop window’s center in a perfectly straight line from (iw/2, ih/2) to (1392.58, 814.3) over the 25-frame zoom‐in (similar to pinch-zooming on a smartphone).

  


  Questions :

  


  


  • How can I express a truly linear interpolation of the crop window center inside zoompan so that the pan path is a straight line in source coordinates ?

    


  


  • Is there a better way (perhaps using different FFmpeg filters or scripting) to achieve this effect ?