USB Sweex 100K Webcam on Linux
The idea was to 'write' a program to handle this (very) cheap webcam ( Sweex 100k
< 10 € ; 16sep2004 MediaMarkt.lg)
on Linux. According to Luca
Risolia's video4linux driver, USB (0c45:6009) is supported by his
driver. But it is for a Linux kernel 2.6 (with video4linux) and I
am presently using a 2.4... So, why not write a little program to
handle the webcam in 'User Space'?. To enhance the portability
and ease development, I would use the libusb. It is the
occasion to fiddle a little bit with an USB device. Luca
Risiola's driver seems/is very good and (seems to) handle a lot of
those 'cheap' webcams. But it isn't that easy to translate into a
'User Space driver' using the libusb library (which is nice but not too
well documented for someone discovering USB programming). So
after some cuts&pastes, interpretations, tries and errors, this is
the very first image I got :-)
Well, it shows some flaws : it is black and white (as I did not
cut/paste the Bayer2RGB routine) and it is not sync'ed (as I let the
start-of-frame header in the image data). I was just so impatient
to check the data I was reading were meaningful... And it
was! :-). Although I don't know yet where the 'little
squares' come from (I suspect it has something to do with the colors in
the Bayer's pattern; I just decided that each pixel gave me a luminance
value (r=g=b)). The program (sweex.tgz)
is still very short at this point. (see further developments by
Gert-Jan C. Prins (AKA Golf) on sweex.nekita.no-ip.com)
... The colors are not perfect yet ;-)
According to this sensor
list, the PAS106B, the 352x288 CMOS color sensor, has pixels of
7.25x7.25 um² and a imaging area of 2.6x2.1 mm².
Sweex MiniUSB webcam
After some adaptation, the program
also works with the MiniUSB webcam. It is a small cam! Very cheap too.
Sold around 10 euros by MediaMarkt in dec2004. It seems to use a
TAS5110C1B Cmos sensor connected to the Sonix SN9C101.
for inside pictures.
According to Geoff Johnson, it is possible to replace the IR-filter
(the little 'glass' glued behind the lens on the 100K) by some 'black
to filter-out usual colors and let pass the IR. It seems to give
interesting pictures (while not quite 'night vision'). I did not try
yet. See his page
24sep2004 -- xof @ S k y n e t .
b e autres bricolages.