Re: [g-a-devel] Gnome accessibility projects list

["Michael Zacherle" <zacherle szs uni-karlsruhe de>]

> > >>> What the tiger prints is an embossed graphic with the picture of the
> > >>> dog,
> > >>
> > >>So not only what I described holds, but it also has an outline 
> > >>detection
> > >>algorithm?
> > >
> > >(for deciding what to emboss in the case of a photograph, for instance)
> >
> > Huh, sorry, I don't know what that means. The Tiger driver has to somehow
> > translate the picture to a dot matrix and then overlay that dot matrix 
> > with
> > braille text.
>
> Yes, and I'm talking about the picture to dot matrix operation.  Unless
> you already have a black and white picture, there's some algorithm that
> is needed to decide which dots should be printed: a yellow object, for
> instance, should probably not have its inside embossed, only the
> outline should.

The driver is doing some kind of transformation to 8 shades of grey. White 
is then left out, black is printed as a dot with full height, and the 6 more 
levels of grey are printed as 6 height levels. There is no outline function 
available.

Ciao

Michael