Comment by idm | Hacker News Reader

Comment by idm | Hacker News Reader

Parent Full thread

This is really neat looking, but ... how exactly do you execute the code? It appears that the release from semacode.com targets cellphones exclusively, so I can't get it to run on the command line.

  wget http://semacode.com/download/semacode_reader_me-1.6.zip
  unzip semacode_reader_me-1.6.zip
  cd semacode_reader_me-1.6
  java -jar semacode_reader_me-1.6.jar

  Failed to load Main-Class manifest attribute from
  semacode_reader_me.jar

A tip here didn't solve the problem either: http://discussion.forum.nokia.com/forum/showthread.php?t=951...

  java -Djava.awt.headless=true -jar semacode_reader_me.jar -f cropfield.jpg

Anyone out there having more luck with this one?

EDIT: Okay... I tried compiling from source, and the problem is that you need the J2ME SDK for the MIDlet libraries.

First, it's not code. It's just a datamatrix that reads "Hello, world!"

Second, you would need to do some heavy filtering and distortion to process the image into a square, readable form. Here's a 1-bit PNG processed from an image taken from the programmer's flickr site. It scanned on my G1 just fine: http://bit.ly/4lxG4U

Cool PNG!

As an update, I'm still trying to get the semacode software to work in OS X, and it's just not cooperating. Sun recently pre-released a J2ME environment for OSX, which is frustratingly buggy...

Here's a link to the SDK:

http://java.sun.com/javame/downloads/sdk30_mac.jsp

...and here's a link to a thread about the (apparently common) issue I'm having:

http://forums.sun.com/thread.jspa?threadID=5412666

Glad to hear semacode JAR works on cellphones. If you get it working in an emulator, please let us know about it!

EDIT: meh, forget it... the Sun SDK just isn't ready for primetime. Instead, I recommend libdmtx:

http://www.libdmtx.org

It's available from macports, there's wrappers for tons of languages (e.g. python), and although it doesn't magically work with your PNG, I think it only requires a little tweaking...

EDIT 2:

Forget the version from macports... just compile from source, and your PNG works fine using version 0.7.2

Reply on news.ycombinator.com