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Eli
May 22, 2006, 15:08:15
We plan to integrate a HSBC (Hue, Saturation, Brightness and Contrast) filter in our implementation.
From the SDK we see that there is a MontiVision Smart Control (ActiveX container) for this application.
But, for our purposes, we prefer to implement a solution using a standard Filter.
How can this be done?

Thank you,
Eli

Marc Cymontkowski
May 22, 2006, 16:53:25
Dear Eli,

You could develop such a filter using either our MontiVision Filter SDK included in the MontiVision Development Kit (Professional Edition) or the standard DirectShow API provided by Microsoft.

By the way, you can use MV Look Up Table to modify brightness, contrast and gamma of an image.


Best Regards,

Marc Cymontkowski

Eli
May 22, 2006, 17:04:42
Dear Marc,

Please elborate how do we use the MV Look Up Table to modify brightness and contrast each seperatly?

Best Regards,
Eli

Marc Cymontkowski
May 22, 2006, 21:34:55
Hi Eli,

If you'd modify brightness and contrast using the same LUT, you'd need to combine those LUTs.

a) You enhance the contrast, that means you stretch a part of the histogram to the full range, e.g. the input from 50 to 205 is mapped to the output from 0 to 255.
(contrast.mvp in attached file)

b) You increase the brightness by the histogram level.
(brightness.mvp in attached file)

Using the filters COM interface, you can calculate your custom LUT in your code and set it to the filter through the interface.
(Both.mvp combines the two above)


Best Regards,

Marc