[sane-devel] AGFA Spanscan E50 USB
Wed, 16 Oct 2002 22:16:22 +0200
On Wed, Oct 16, 2002 at 03:10:47PM -0400, Bob Lockie wrote:
> I'm confused why v4l knows which USB devices are video devices.
> Is the ID's of my webcam in the v4l driver?
I don't really know. There are two possibilities: Either the USB
driver of your camera knows all the ids that it can support. Or there
is a generic driver that supportes all the USB devices of one class.
The problem with the USB scanners is that ther is no galg "I'm a
scanner" like with SCSI scanners. That's the reason why
sane-find-scanner can only guess, if it uses libusb to access
scanners. It does things like "If it's not a hub and not a keyboard
and not ... it is possibly a scanner". The other way is what is donner
in scanner.h: list all known devices.