Re: Gamma Correction VHDL Core

On Jun 30, 9:33 am, Martin Sauer <m...@[EMAIL PROTECTED]
> wrote:
> Hi,
>
> I'm looking for a gamma correction vhdl code. Do anything know about
> such cores?
>
> thank you for your answer
>
> bye
>
> martin sauer

I'd suggest the following:
1. Go to Wikipedia for the fundamental equations for gamma correction
(unless you know them already).

2. Realize that to implement such a function you only need a lookup
table for whatever your input data width is (i.e. 8 bit video = 256
entry table).

3. Write a simple VHDL function to compute the above mentioned table.
In order to do this for gamma correction, you'll see that you need log
and powers and real number computations.  While you can't syntheize
type real for 'signals' you can use type real to compute 'constants'
which is what you're trying to do here.  For a related example that
demonstrates this see the link below or Google for "Sample code to
compute an sRGB->RGB conversion lookup table" in which case you should
run across the posting that I did that shows this.

http://groups.google.com/group/comp.lang.vhdl/browse_frm/thread/b2e4be6480069641?hl=en#

Kevin Jennings