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  1. vid2mp4

    Videos with H.264 video and AAC sound im MP4 containers seem to strike a very good size performance balance. So I modified a copy of vid2mkv to use ffmpeg to create this kind of files instead.

    To speed up the processing of multiple files, this script runs the conversions ...

  2. Alternative power

    date: 2015-08-02
    original date: 2010-01-05
    category: energy
    tags: solar PV

    I’ve been reading the walden effect blog, and a comment thread there led me down some interesting avenues that I’d like to share.

    When they blogged that a power outage stopped the fan in their furnace from working, I immediately thought that it would be neat if there ...

  3. Backups

    People usually have to learn the hard way that backups are important. For people not familiar with computers it takes time to appreciate the nature of digital data. Digital data is easy and cheap to create and copy, but equally easy to destroy and lose! It is very easy to accidentally delete files.

  4. Chickpea and vegetables stew

    This is a variation on a recipe that I found in a cookbook, because some of the ingredients in that cookbook aren’t in season right now.

    The ingredients I used were:

    • one can of chickpeas (400 g)
    • one can of diced tomatoes (400 g)
    • 250 grams of French beans ...
  5. EPUB">Making my first EPUB

    Now that I got an EPUB reader, I started looking for a way to make EPUB documents.

    In principle, an EPUB file is a zipfile with a certain layout, as can be seen on the wikipedia page linked above.

    The actual contents are just XHTML, while the metadata files are ...

  6. Managing configuration files

    Configuration files for UNIX-like systems and the programs that run on them are usually plain text files. They tend to come in two flavors;

    System files
    These files live in /etc or /var or /usr/local/etc and control the running of the system and additional software, for all ...
  7. Me at work

    It occurred to me that I only rarely have a picture taken with me in it. Usually I’m the one holding the camera. So here are a couple of “action shots”. :-)

    R.F. Smith performing a flamability test R.F. Smith during infusion of a first prototype

    The first picture is me doing an informal test to see if a material that we made is ...

  8. New Zealand 2013/2014: favorite pictures

    At the end of 2013 and beginning of 2014 I spent a month on holiday in NZ, and had a great time. Below is a selection of my favorite pictures from that holiday.

    The comments are interspersed between the pictures. They belong with the picture above.

    img_2363.jpg img_2364.jpg

    The beach at Napier ...

  9. onepad

    This is a set of programs to encrypt files using one-time-pad encryption. This is an old but theoretically impossible to easily break way of encryption. I came across this method in Neal Stephenson’s Cryptonomicon.

    It works by XOR-ing every byte in the cleartext message with a byte in ...


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