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Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

Last 100 entries

NSA Interceptng Gmail During Delivery; General IIR Filters; What's happening with Scala?; Interesting (But Largely Illegible) Typeface; Retiring Essentialism; Poorest in UK, Poorest in N Europe; I Want To Be A Redneck!; Reverse Racism; The Lost Art Of Nomography; IBM Data Center (Photo); Interesting Account Of Gamma Hack; The Most Interesting Audiophile In The World; How did the first world war actually end?; Ky - Restaurant Santiago; The Black Dork Lives!; The UN Requires Unaninmous Decisions; LPIR - Steganography in Practice; How I Am 6; Clear Explanation of Verizon / Level 3 / Netflix; Teenage Girls; Formalising NSA Attacks; Switching Brakes (Tektro Hydraulic); Naim NAP 100 (Power Amp); AKG 550 First Impressions; Facebook manipulates emotions (no really); Map Reduce "No Longer Used" At Google; Removing RAID metadata; New Bike (Good Bike Shop, Santiago Chile); Removing APE Tags in Linux; Compiling Python 3.0 With GCC 4.8; Maven is Amazing; Generating Docs from a GitHub Wiki; Modular Shelves; Bash Best Practices; Good Emergency Gasfiter (Santiago, Chile); Readings in Recent Architecture; Roger Casement; Integrated Information Theory (Or Not); Possibly undefined macro AC_ENABLE_SHARED; Update on Charges; Sunburst Visualisation; Spectral Embeddings (Distances -> Coordinates); Introduction to Causality; Filtering To Help Colour-Blindness; ASUS 1015E-DS02 Too; Ready Player One; Writing Clear, Fast Julia Code; List of LatAm Novels; Running (for women); Building a Jenkins Plugin and a Jar (for Command Line use); Headphone Test Recordings; Causal Consistency; The Quest for Randomness; Chat Wars; Real-life Financial Co Without ACID Database...; Flexible Muscle-Based Locomotion for Bipedal Creatures; SQL Performance Explained; The Little Manual of API Design; Multiple Word Sizes; CRC - Next Steps; FizzBuzz; Update on CRCs; Decent Links / Discussion Community; Automated Reasoning About LLVM Optimizations and Undefined Behavior; A Painless Guide To CRC Error Detection Algorithms; Tests in Julia; Dave Eggers: what's so funny about peace, love and Starship?; Cello - High Level C Programming; autoreconf needs tar; Will Self Goes To Heathrow; Top 5 BioInformatics Papers; Vasovagal Response; Good Food in Vina; Chilean Drug Criminals Use Subsitution Cipher; Adrenaline; Stiglitz on the Impact of Technology; Why Not; How I Am 5; Lenovo X240 OpenSuse 13.1; NSA and GCHQ - Psychological Trolls; Finite Fields in Julia (Defining Your Own Number Type); Julian Assange; Starting Qemu on OpenSuse; Noisy GAs/TMs; Venezuela; Reinstalling GRUB with EFI; Instructions For Disabling KDE Indexing; Evolving Speakers; Changing Salt Size in Simple Crypt 3.0.0; Logarithmic Map (Moved); More Info; Words Found in Voynich Manuscript; An Inventory Of 3D Space-Filling Curves; Foxes Using Magnetic Fields To Hunt; 5 Rounds RC5 No Rotation; JP Morgan and Madoff; Ori - Secure, Distributed File System; Physical Unclonable Functions (PUFs); Prejudice on Reddit; Recursion OK; Optimizing Julia Code

© 2006-2013 Andrew Cooke (site) / post authors (content).

It's Official - I Rock

From: "andrew cooke" <andrew@...>

Date: Sat, 30 Jun 2007 23:25:11 -0400 (CLT)

Yay for me!  My Airport Express just answered.

Sun have a bug in their fucking crypto library.

Bouncy castle rock even more than me.

A Java/Jack port of JustePort coming soon to a computer near you...

Andrew

Sine!

From: "andrew cooke" <andrew@...>

Date: Mon, 2 Jul 2007 21:58:46 -0400 (CLT)

Spent some time playing with this after work today and just got a sine
wave out of the speakers.  Woot!

(This has been a "learning experience".  Spent way too long trying to
compare my output with JustePort for a known RSA key.  If that seems
reasonable to you, too, then you don't understand Optimal Asymmetric
Encryption Padding either, fool! :o)

Andrew

I Am A Foooool..

From: "andrew cooke" <andrew@...>

Date: Sun, 8 Jul 2007 18:12:54 -0400 (CLT)

The noise, it is not good.  Zeroes give silence, and fake sines sounded
like they were fake sines (at least, the frequency sounded to drop when I
doubled the period), but looking at the output from the Airport via my
oscilloscope it's clear that I have something very wrong indeed.

Channel separation is OK (despite not sounding that great through
headphones) - am now worried about the rest of my hifi, but that can wait.
 But fidelity is not.  Looking again at the code I think I may need to
reverse my endianness...  I guess swapping byte order is not enough, those
bits are important too, huh?

Andrew

More of a Wobble

From: "andrew cooke" <andrew@...>

Date: Sun, 8 Jul 2007 19:31:35 -0400 (CLT)

OK, so the prev comment makes no sense.

I now have beautiful sine waves.  The problem?  It really isn't an 8-bit
aligned data stream.  There really is a 23 bit header!  Hence the random
noise that kept appearing.

Still, the good news (apart from the damn thing working - I guess I should
be able to pipe music through it now) is that uncompressed ALAC really
does just interleave channels.  No sum/difference.

I guess I should try putting music through...

OK, so music doesn't work - I guess that's the Jack side of things.  But a
sine wave sounds smooth.  Maybe I should just start listening to sine
waves.

Andrew

Woot - Jack to Airport

From: "andrew cooke" <andrew@...>

Date: Mon, 9 Jul 2007 21:53:13 -0400 (CLT)

Credence, of all things (hey, it was just the first directory I found with
some ogg files) is now coming out of my speakers...  Yep - I now have a
Jack client that talks to Airport Express! :o)

Three things to do now:
1 - Clean things up and package them for a 0.0 release
2 - Work on improving sound quality
3 - Work on improving streaming quality

(2) includes fixing some ugliness in the code that is losing data (I'm not
sure if the noise I'm hearing at the moment is the original recording or
not).

(3) means worrying about the difference in clock rates between the airport
and jack.  Also, discovery of the IP address would be nice.

All this should be fairly easy (within reason - I have no magic solution
for synchronizing clocks, for example) now that the the basics work.

I guess I should pack away my ancient (HP, valve, older than me)
oscilloscope too...

Andrew

jjjuste V 1.0 Released

From: "andrew cooke" <andrew@...>

Date: Wed, 11 Jul 2007 21:22:46 -0400 (CLT)

I just released an Airport Express client for Jack:
http://www.acooke.org/jara/jjjuste/

Andrew

This project died soon after...

From: "andrew cooke" <andrew@...>

Date: Thu, 25 Dec 2008 17:48:57 -0300 (CLST)

The streaming was never very reliable, and it was a lot of fuss.

For what to do instead, see comments here:
http://www.acooke.org/cute/AirportExp0.html#Tue23Dec20080954590300CLST

Andrew

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