[sane-devel] plustek:libusb bugs on canon canoscan n1220U

[Gerhard Jaeger]

On Wednesday 09 August 2006 13:49, Étienne Bersac wrote:
> Hello,
> 
> > scanimage -L reports: 
> > device `plustek:libusb:003:003' is a Canon N1220U USB flatbed scanner
> 
> User should have 
> 
>         bersace at celebrad:~$ scanimage -L
>         device `plustek:libusb:002:002' is a Canon CanoScan N1220U flatbed scanner
>         					   ^^^^^^^^      ^^^

I decided not to add "CanoScan".

> 
> The USB in "USB flatbed scanner" is very annoying since that make type
> parsing hard if an app want to show an icon representing the type of the
> device. I guess an enum should be better than string.

NACK - the type is descriptive. I agree, "USB" is too much, I've changed that
for all affected backends.

> 
> > SANE_TYPE_OPTION does not exist
> 
> Sorry, i meant SANE_TYPE_{BOOL,INT,FIXED,STRING}.
> 
> The 5 options "button" have SANE_TYPE_BOOL as type (in
> SANE_Option_Descriptor struct). That should be SANE_TYPE_BUTTON.

Also NACK. SANE standard 1 does not specify how to handle scanner buttons,
but it is clear, that an option, which deals with a button has to deliver
a value (button pressed or not). Regarding that requirement, you have either
to use SANE_TYPE_BOOL or SANE_TYPE_INT - I choose BOOL.
SANE_TYPE_BUTTON is maybe misleading. It is intended to be used by a backend
to allow changes by pressing that button from the GUI and NOT to reflect
the status of a scanner button. An option of type SANE_TYPE_BUTTON has no value.
See also chapter 4.2.9.4 of the SANE Standard 
http://www.sane-project.org/html/doc011.html

Ciao
Gerhard