[sane-devel] sane-sp15c and Fujitsu 620c: Help needed for plumbing backend to frontend

Frank Zago fzago@austin.rr.com
Thu, 25 Mar 2004 02:44:15 -0600

Garrick Sitongia wrote:
> The brightness and contrast levels are presently not supported by the=20
> sp15c backend. These are presently hardcoded at 128. But I was able to=20
> get it working in the hardware by adding "scanf" statements in sp15c.c.=
> Scanimage stops and I can enter numbers for brightness and contrast eac=
> time I run scanimage.
>   scanf("%d", &c);    /* my code */
>    =3D c;
>  dev->threshold =3D 128;
>   scanf("%d", &c);    /* my code */
>  dev->contrast =3D c;
> How instead do I pass these numbers to the backend from scanimage? Wher=
> scanimage would get them the usual way from command line args?
> Garrick
> _________________________________________________________________
> FREE pop-up blocking with the new MSN Toolbar =96 get it now!=20
> http://toolbar.msn.com/go/onm00200415ave/direct/01/

It seems that the backend has these options, but they are de-activated al=
all the time.

In sane_control_option(), see all the lines like
    scanner->opt[OPT_BRIGHTNESS].cap =3D SANE_CAP_INACTIVE;

This tells the frontend not to offer the option.

You can change some to
    scanner->opt[OPT_BRIGHTNESS].cap &=3D ~SANE_CAP_INACTIVE;
to activate them.

Then, if the option is active, use the value with
   dev->brightness =3D scanner->val[OPT_BRIGHTNESS].w;

Hope that helps,