My second (personal) iPhone app, C10CK, is now available in the App Store. It is a clock which displays time using binary notation – the same way everything is (eventually) stored in a digital computer. I’ve been using a binary clock since a staff member of ITP passed this past year and several alumni recalled stories of the binary clock she kept on her desk and would happily explain to anyone who asked. I now keep a binary clock on my desk and think of her when people ask me what it is. Read the rest of this entry »

Update: New version built around a native Cocoa port of ShairPort, MacShairport: ShairPort-v0.2.1.zip)

Recently an open source emulator for AirPort Express / AirTunes was released by James Laird. I’ve been waiting for something like this for a long while to enable remote music playback on my media center from my laptop and iPhone. However, I lack the hardware skills to extract the necessary firmware from the AirPort Express ROM chip. Thanks to James for doing the work and putting out his perl script / c utility. It’s pretty simple to build and run, and the source includes a nice OS X launcher script, but I’m looking for a little GUI widget to easily control it lest someone ‘inadvertently’ decides to send audio to my computer.

I’ve been lately transitioning my iPhone-specific Cocoa knowledge to the desktop; this was a nice opportunity to wrap up the ShairPort scripts in an OS X menu bar widget. The source is available on Github, and you can get the bundled app below. This was made for my specific system, so YMMV.

ShairPortMenu: [download]

For this year’s Philadelphia Fun-A-Day project I decided to write “Hello World” programs. “Hello World” is a traditional programming tradition where a programmer encountering a new language writes a trivial program which displays the phrase “Hello World”.

This introduces the programmer to the basic syntax of the language and demonstrates that their development environment is set up properly to work with that language.

Much of our current environment runs on software, which is generally invisible to us, except when a failure impacts our lives. However, software generally starts as human-readable written text, albeit in a highly defined form using specific vocabulary.

This project attempts to make software visible, in at least a trivial way. The words and structure may differ between languages, but each program is a series of instructions to achieve some end – here to issue a friendly “Hello Fun-A-Day 7!”. Hopefully this can serve to demystify software to some degree, and remind us that software, at some point, has been written by a person.

The programs here demonstrate a Fun-A-Day variant on Hello World in several languages. I made an effort to explore historical and modern languages, compiled and interpreted languages, console and graphical programs, but avoided esoteric languages which are often difficult to understand by design.
Read the rest of this entry »

Update 2: Before using the script, ensure that you can build tesseract for your host system normally. Also, I only tested the script with the v3 release of tesseract, not svn HEAD. If you get build errors, please try with rev 498.

Update: The script has been updated, thanks mostly to the prompting of fopen2003 in the comments below. I’ve successfully tested the resulting libs in both Simulator and an iPhone 4 (both at iOS4.x) using the PocketOCR project.

After many requests, I finally got around to looking into updating the build script to cross-compile tesseract ocr v3 for use with iPhone. Here’s the script. It seems to build the static, fat library without error. I haven’t tried to update my app to use it yet, so I really don’t know if it even works. Let me know in the comments if it actually does indeed work.

1. Check out the svn source of tesseract: http://code.google.com/p/tesseract-ocr/source/checkout
2. Copy this script into the source directory and run from there
3. Profit???

Read the rest of this entry »

I’ve been working sporadically on the app, trying to get the next release out the door.

Currently, the last feature holding up release is the post log upload…there are intermittent timeouts occurring and I’d like to determine if there is a lightweight way to mitigate them.

This upcoming release will likely change the “real-time” uploading to opt-in. There are two primary reasons: conserve significant battery life and to alleviate the server load from new data.

The battery savings are great…I’ve gone from close to 20% to less than 10% use over a 35 minute ride.

I’m getting low on space on the server, with about 550 hours of data logged – which is awesome – thanks to everyone who has shared their log data. However, I haven’t yet had an opportunity to visualize it and am feeling a bit overwhelmed by it. Hopefully this will throttle that a bit.

So, that’s the status…stay tuned!

Got two new features rolled into Mobile Logger at once…raw database export and zip compression. This sounds exciting, right?!

Actually, it’s pretty cool and useful. Some of these new export formats (GC and GPX, I’m looking at you) are XML-based and thus quite verbose. What was a manageably small CSV file or JSON string has become inflated much larger from all the tagging in these formats. Exporting a log in one of these formats means having send a doubly large file (approx. 300kB -> 600kB). However, all the repeated tags makes them great candidates for zip compression. Those logs are about 70kB afterwards. So there’s that. Read the rest of this entry »

Justin added a Twitter posting feature to Golden Cheetah a couple weeks ago. However, it used basic authentication, which Twitter has announced is going away in favor of OAuth only. So, after several more days of coding he did a bang up job of rolling in support using liboauth.

Now, getting liboauth and it’s prerequisites configured to play nicely with my Golden Cheetah dev environment has been another struggle. I have been making the OS X releases of Golden Cheetah for a while – and we package them as a universal binary (i386/ppc) with 10.4 support. I’ve had to custom compile Qt, QWT, srmio and all that stuff to enable this.

In brief, liboauth needed to be compiled against the same arch that GC and co. have been, and it really wanted to go native, eg x86_64 on my MacBook Pro. After a night and day of tinkering…here’s what worked. Thanks to Justin for getting this going.

Export config flags (just makes life easier on the command line):

export CFLAGS=-mmacosx-version-min=10.4
export CPPFLAGS=-mmacosx-version-min=10.4

openssl 1.0.0a:

./config -m32

liboauth 0.8.8 / curl 7.21.1:

./configure CC="gcc -arch i386" CXX="g++ -arch i386" -host i386

Golden Cheetah:

After getting linker errors for a while, I realized that I had to directly link to the static version of libcrypto that was installed alongside libssl in /usr/local/ssl.

Undefined symbols:
  "_EVP_MD_size", referenced from:
      _oauth_body_hash_file in liboauth.a(liboauth_la-hash.o)
      _oauth_body_hash_data in liboauth.a(liboauth_la-hash.o)
ld: symbol(s) not found

Here’s the relevant bit of src.pro:

!isEmpty( LIBOAUTH_INSTALL ) {
INCLUDEPATH += $${LIBOAUTH_INSTALL}/include
LIBS += /usr/local/ssl/lib/libcrypto.a
LIBS +=  $${LIBOAUTH_INSTALL}/lib/liboauth.a
LIBS += -lz
LIBS += -lcurl
DEFINES += GC_HAVE_LIBOAUTH
SOURCES += TwitterDialog.cpp
HEADERS += TwitterDialog.h
}

Rolling the extra logged sensor data into the GPX export took more effort that it should have…but I uncovered and fixed a latent bug in the export feature, so that’s a win right? Regardless, it’s was nice to use the new issue tracker at bugs.robertcarlsen.net for real(z) for the first time. I’m looking to get several other features implemented before the next released update…planning on a few weeks. Otherwise, code is available, as always, on github.

GPX export seems to be working, and imports fine into Google Earth. This is just a basic implementation of the essentials for a route; I’d really like to include other recorded sensors somehow into the track – maybe it could be a layer in Google Earth?

Looking at the ride data here reveals just how bad raw GPS data can be between tall buildings in NYC. Several data points often share the same GPS location. It seems that moving quickly with a clear path to the sky gives the best performance.

The app also quit midway though the ride – I have to look into that.

GPX export is available in the github repository.

Basic GPX export has been added to the github repo. That is all.

http://github.com/rcarlsen/Mobile-Logger/commit/9e1dc73304de562c30e64fa9a9b61840e69963c3