[Elphel-support] Focus Helper

[Oleg]

> How 'focus helper' works?

The link to the 'focus helper' is http://<my-cam>/focus.html

After the DCT transform of a 8x8 block the 64 frequency coefficients are
aquired. Each coefficient is squared and multiplied by the value from the
table of weights (it can be set) and a single value for a block is the
result. For better focus the lower frequencies go with greater weights (more
attention to details). Then the sum of the squared (one more time) values of
all the blocks in the focus area is taken and it is the length of Green
Horizontal Line.

So, by setting the table of weights the higher/lower frequencies can be
filtered.

Oleg
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://support.elphel.com/pipermail/support-list_support.elphel.com/attachments/20091215/ee63f83f/attachment-0002.html>