Patern matching

[Amir___]

Hi all,

I'm sampling a led with a camera, and processing the stream of data with the Labview.

To determine whether the led is on or off, I'm using the pattern maching vi.

My problem is that the led is stationed outdoors, and hence the lighting is changing during day and night, while the template is still the same.

So, is there a way of refreshing the template every now and then, so the matching would be more accurate?

Secondly, how can I create a ROI as an interface from the panel?

Thanks a bunch,

Amir Klein.

[ThSa]

Hi Amir,
why you are working with pattern matching?
I think in your case it would be better to work in HSL (hue - saturation - luminance).
Extract from your picture the saturation and hue and apply them in a XY graph (x: hue and y saturation).
In most cases hue and saturation is enough, otherwise you can take hue and luminance (try it out which combination is the best one in your case)
With the help of the diagram you can fix iempirically the areas for the LED colors.

The advantage is, that you have far less problems by change of the surroundings light.

Regards,
ThSa