Re: Re(2): Quickcam device driver for Linux
The camera interface code is rather tricky, given the various
operating modes of the camera, it's polling nature and the
documentation which in some places is hard to understand.
I ended up writing my own camera picture capture code for the color camera
since I wanted to do it a bit differently. There are at least
two other libraries for picture capture that I know of. The fact that the
camera driver code is a normal user process makes this experimentation
possible. Once you implement it in as a device driver, people aren't
going to want to mess with it, and improvements will cease.
The current user mode capture libraires require only one non-portable
thing: access to a few registers of the parallel port. This is
trivial on Linux and, I would suspect, on most of the other free x86
Unixes. For those OS'es running on machines with pc-compatible
parallel ports that don't offer easy access to the parallel port,
then this is when you want to put in some kernel hacks to access
that port. Adding such hacks will certainly be much easier than adding
an entire qcam driver.
I think that the device driver just doesn't buy you anything.
I doubt that you'll be doing cat < /dev/qcam > mypic
since there are so many parameters to set before you can take
In short: let's keep the capture code out of the kernel and in
user space were we can all hack on it and share it among platforms.