Read Me

    simpledc1394jni
    ===============
        
    Version 0.1 alpha
    11 April 2009

    Copyright 2008 Sascha Liebsch <elkmonster@users.sourceforge.net>


1. About simpledc1394jni

This library provides access to DC1394-compliant cameras from the Java language. 
It uses JNI (Java Native Interface) to speak to the native part of the library, 
which in turn uses libdc1394 (libdc1394.sf.net) to access the camera.
simpledc1394jni intends to provide access to a very limited spectrum of the 
abilities of libdc1394. 
 
 
2. Motivation

The reason to start this project was that I could not get jlibdc1394 
(jlibdc1394.sf.net) to run. Also, it seemed overly complicated to set up, the 
documentation did not help a lot, and last but not least, it is for version 1 of 
libdc1394. However, simpledc1394jni does not strive to be an update or 
replacement for jlibdc1394, but rather a simple alternative for those who do not 
demand much.


3. Compilation / Installation

Please refer to the instructions given in BUILD.


4. Running it

After compilation, you can run an example application that simply shows the 
camera image. The BUILD file describes how to do that (under 3. Testing).


5. Supported Cameras / Modes

simpledc1394jni should basically work with every camera that libdc1394 supports. 
However, the current implementation is limited to correctly read monochrome 
images, i.e., greyscale images. Using a video mode other than monochrome will 
result in an distorted image (because the image data is still handled as 
monochrome, hence the interpretation of bytes is not correct).
The reasons for this limitation is that this project was originally started with 
the very aim to be able to capture greyscale images. If somebody wishes to 
add support for additional modes, please do so and get in contact.


6. Troubleshooting

If the test application fails, make sure you have read and write access to the 
video device file on your system. Usually, it should be something like 
/dev/videoN or /dev/v4l/videoN, where N is a number. Be sure to follow symlinks, 
as sufficient access rights to a symlink does not automatically mean that you 
have the same rights for the links target file.

In general, it is also advisable to check whether Coriander (coriander.sf.net) 
is able to access the camera. If it is, then so should be simpledc1394jni.

Remember that currently, simpledc1394jni will only deliver correct results in 
monochrome video modes.

If a program that uses simpledc1394jni has crashed or is killed and fails when 
trying to restart it, then try to disconnect the camera from the computer 
shortly to free blocked resources. It is a common problem when libdc1394 is not 
shut down correctly.


7. The Code

The code is currently in a questionable state. As my C(++) skills have gotten a 
little rusty, and as the aim was to get it running in the first place, the 
source files are rather untidy and contain debatable workarounds and 
improvisations. This mess will be resolved eventually. This is also true for 
many of the messages written to the shell.


8. The Library's Name

The name was just born out of necessity to find one. I am well aware that it is 
neither creative nor sounds good at all, but I just couldn't think of anything 
better. If you have got an idea, tell me and I'll consider it.


9. Contact

Please use the SourceForge mailing lists or forums to get in contact, or the 
SourceForge email address given at the top.