[PD] GEM: pix_convolve scale factor?

[Matteo Sisti Sette]

Hi,

I've noticed that the "smooth" filter in the example patch for 
[pix_convolve] has a wrong scale factor which results in a slightly 
darker output image than the input.

I don't know much about convolution filters, but the number being bassed 
to [pix_convolve] seems right to me: 0.0625 which is 1/16, and it seems 
right since the sum of the coefficients is 16.

Is the number being passed as scale factor in the help patch wrong, or 
is there a bug in [pix_convolve]?

Or is this the expected result in a way I don't see?

thanks
m.