# Re: 16 bit per sample support

Oliver Rauch (oliver.rauch@Wolfsburg.DE)
Mon, 05 Apr 1999 14:01:11 +0200

- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
- Next message: Oliver Rauch: "Re: Sane drivers"
- Previous message: Milon Firikis: "Re: Sane drivers"

Jonathan A. Buzzard wrote:

>
>
> For example I might have three Xrays of an object, that after some sort
> of registration I wish to stack on top of one another. The Xrays have
> been scanned say at 12 bits, now if you have stretched them though to
> the full dynamic range of 16 bits adding the pixel values together
> will result in loss of information. If they had stayed as 12 bits inside
> a 16 bit value there is no problem.
>
> These are dozens of similar cases where stretching the values is simply
> not acceptable. A little check button somewhere which can be unchecked
> for those that don't want stretching would suffice.
>

Hi Jonathan,

there is no real problem with that.

If the 12 bits are streched to a 16 bit range, the lower 4 bits are simply not
used.
If you want to add two images, you have to dived the values by two before you
add
the values.

In 8 bit mode it is the same, you get more than 8 bits if you add two 8 bit
values.

It is not the sense of SANE to deal with such special features.
SANE is for scanning, we don`t want to make a new pixelgraphic program like gimp

or a program to evaluate any measurements.

Bye
Oliver

    --
    EMAIL: Oliver.Rauch@Wolfsburg.DE
    WWW: http://www.wolfsburg.de/~rauch

    --
    Source code, list archive, and docs: http://www.mostang.com/sane/
    To unsubscribe: echo unsubscribe sane-devel | mail majordomo@mostang.com

     Next message: Oliver Rauch: "Re: Sane drivers"
     Previous message: Milon Firikis: "Re: Sane drivers"