[sane-devel] "gamma" and "bayer" ? What are they?

[Theodore Kilgore]

On Thu, 12 Jun 2003, Peter Fales wrote:

> > Maybe your data is also compressed? Or it's transferred as a jpeg?
>
> For a toy camera like this, it's most likely the raw output of the CCD
> device and needs a fair amount of processing of the raw pixel data.

Actually, I suspect it is a CMOS chip. The camera really is cheap.

> The
> dc25 backend shows an example of this kind of processing.  (It's not likely
> that you'll be able to use that kind - just an example of that type of
> processing.)
>
> My guess is that the most effective technique would be to open up the camera
> and try to identify the manufacturer of the CCD.

And how would I do that identification if there is nothing written on
said chip? Since I have already destroyed one of these things trying to
look inside, I would be glad to look in it again (can't kill it twice,
after all) if it would really help.

And anyway the USB vendor:product number is 0x2770:0x9120, which tells us
that the chip is from SQ Technologies ( website at www.sq.com.tw ) and
they do claim to make video capture chips. They make an SQ905 and an SQ913
in particular. I suspect the one in this camera is the SQ905 (there is no
912) They have publicly available "data sheets" which are nothing but
glossy sales brochures.

Then see if you can get
> anything from them.

Good idea. They don't answer my e-mail.


I think that's how the dc-25 algorithms were
> originally developed (not by me!)
>
Hmmm. I will have a look.

Thanks.

Ted Kilgore