[sane-devel] HP5470c scanner nearly working!

Bertrik Sikken bertrik@zonnet.nl
Sat, 22 Feb 2003 14:10:32 +0100


Martijn van Oosterhout wrote:

>On Thu, Feb 20, 2003 at 09:19:26PM +0100, Bertrik Sikken wrote:
>
>>In the hp3300, the calibration table uses a 16-bit word for each
>>calibration value, lower 6 bits are offset and upper 10 bits gain.
>>
>
>Actually, I just remembered. Here is a huge difference. The calibration info
>on the hp5470 amounts to 12 bytes per pixel. Three small 16 bit integers
>(around 0x05e0) and three large 16 integers (around 0xa000). That why I
>think that they're max and min values. At the moment they're hardcoded
>because without anything it just produces nothing useful.
>
>I'll look into all this tonight.
>
Your idea sounds very plausible, since the hp5400/5470 seems to contain
much more intelligence than other scanners with a niash chip.
Only experimentation can tell how this works probably.

Regards,
Bertrik