On Apr 24, 4:43 pm, "Simon Johan" <si...@[EMAIL PROTECTED]
> wrote:
> The idea is to generate a look-up table with all the computed
> multiplications, so when an output pixel is to be calculated it only
> multiplies numbers not previously multiplied. Otherwise it fetches the
> result from the table. Provided that a look-up operation is faster than
a
> multiplication, this will lead to speed improvements.
Not sure what you are trying to do.
The convolution is unique, so for each superposition, you will have to
multiply and sum over the entire input and impulse response x[m][n] *
h[j][k].
If I understand you correctly, what matters is whether you are about
to multiply two values already seen. In that case, you'd have a lookup
table for _those_ two values without concern for where they were in
the matrices. Unless your multiplications are expensive, there is no
point, as you undoubtedly already know.
If you find that a new input image x'[m][n] has identical pixels in
the same positions as x[m][n], then again, you can only know this when
you know this, and same argument applies.
If you are talking about reconvolving an already-seen input with h[m]
[n]...well then..there is no problem. ;)
-Le Chaud Lapin-
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