free software

timelapse aka speeding up with ffmpeg

These days I’m recording my work in the studio using a timelapse function in my Panasonic TM700 HD camera. So it happened that I forgot to turn on the the function (needs to be turned on everytime you start recording) which usually records one frame every 10 seconds, so I ended up with a “normal” recording and wanted to convert that to what camera usually does. Ffmpeg to the rescue! To do some frame manipulation a video filter “setpts” is what one needs. Gathering knowledge online with help of two pages:

http://blog.grio.com/2012/01/fast-and-slow-motion-video-with-ffmpeg.html
https://trac.ffmpeg.org/wiki/How to speed up / slow down a video

So, supposedly, the right way to change video speed using ffmpeg is by adjusting the “presentation time stamp” (PTS). This adjusts frames’ metadata related to how long each is displayed—exactly what you want.

this is the crucial piece of code that needs to be passed to ffmpeg:

-filter:v "setpts=2.0*PTS"

Or a more practical example using fraction – if original framerate is 25 frames per second I only need evert 250th one:

$ ffmpeg -i INPUTFILE.mkv -filter:v "setpts=(1/250)*PTS" OUTPUTFILE.mkv

My final conversion was from full-HD .mts to 720p .webm and to mp4:

$ ffmpeg -i INPUT.mts -filter:v "setpts=(1/250)*PTS" -s 1280x720 -c:v libvpx -crf 5 -b:v 8M -an OUTPUT.webm
$ ffmpeg -i INPUT.mts -filter:v "setpts=(1/250)*PTS" -s 1280x720 -c:v libx264 -preset slow -crf 10 -an OUTPUT.mp4

pablo soto & torrents.com: a way to give control back to the people

“We believe that the most powerful weapon we have in this important battlefield is Free Software. Constructing search engines, P2P servants, robots and what not, and releasing them all under a free license that lets everybody read the code, modify it, and replicate it, is a way to give control back to the people.”

via Most Important Torrent Site in Years to Take the Internet By Storm | TorrentFreak.

linux is a process, not a product

This is an essay that I wrote for IDOCDE (International Documentation of Contemporary Dance Education) project/website last week in Lunow-Stolzenhagen. It is an attempt to explain what FLOSS essentially is using some analogies. Feedback welcome.

Here’s a story.

Imagine yourself going to a workshop by an amazing dance professional who is teaching a movement technique that is the latest and greatest thing ever. You pay for it and work on it weeklong and you are amazed and thrown off your feet (literaly too) by its beauty, elegance, thoroughness, radicality, inventiveness – in short THAT is the most amazing method of movement that enables lighting-fast progress with your body and movement.

You think and realize you want to share this with your local peers. What’s more, you want to improve on it, merge the technique with some of your own discoveries during the years of your practice. You plan a workshop and a short sketchbook. You will fully credit the amazing dance professional. People will be thrown off their feet like you were, and will take it further, enrich it with their own ideas, use it in their work, make their own workshops for others to see and learn. This is how progress is made, isn’t it? By building on each other’s work. You learn something, you improve it, and you share it with others, so they can learn, improve and share it with others. People talk about it, mention names and peers, good practices survive, bad ones are left behind. You can be cherished if your work is distributed, mentioned and built upon.

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does software (re)produce identities and ideologies?

Situated on the “freedom” side of technology, the Free Software movement strives for equal possibilities of all citizen to use, modify, adapt and copy software for their purposes. Even if Free Software is open to everyone’s use and contribution, this is hardly the case in reality. On the opposite, it is seen as a closed movement of people with often a similar description: mostly white, mostly young, mostly Western country citizen, mostly male. Why is free software associated with this white-young-male personality and not with something else? Does software reproduce identities and ideologies, and if so, how can contributors and users of Free Software change the stereotype?

Keynote: Hackers for Social Justice by Christina Haralanova

“Free software projects are not products”

One of the best things to happen if you are a free software developer is to see your code cropping up in other projects. […]

To me this highlights how thinking about free software in terms of being products (in a consumer capitalist sense) is an ill fit. This kind of cross pollination is really “the point” of free software, and would be, by necessity full of barriers if these projects were proprietary.

The problem is that it’s very hard for us to see outside of these ideas when they are so ingrained in our world and our thinking. It’s sometimes valuable to try and outline these assumptions, and become more aware of them.

The popularity in terms of raw market share is an interesting metric for a free software project as it has a kind of irrelevance or is even an obstruction when users are not supporting the project somehow. In the same way, the definition of “user” and “developer” seem a hangover from the same kind of producer/consumer thinking we are interested in finding the edges of.

What we want to know is what kind of people are using the project, are they curious, will they fiddle with things, do they blog about the work they are doing, can they translate the documentation? Most of all, will they increase the energy surrounding the work? People that do that are precious.

via dave’s blog of art and programming | Free software projects are not products.