Labview Colour

[jack619]

Hi all,

I am a student at the School of Arti and Mestieri Bellinzona and I have to carry out a project through a USB camera and LabView.

My goal is to recognize colors but I can't figure out how to do it.

Could you help me?

[rolfk]

Do you have a LabVIEW IMAQ Vision license? What have you tried so far?

We do not solve class assignments here but answer specific questions if something does not work.

[jack619]

I have the license and I have a usb camera. I tried with vision assistant but I don't know what function I must to use.

I used "color Location" and "color Classification".

It is not a class assignment but it is a project that doesn't work and i ask for help.

If you have any examples could you send me please?

[Bob_Schor]

Image processing is (in my mind) "Advanced LabVIEW", something to tackle after you've spent 4-8 months doing semi-serious LabVIEW programming.

To start to answer your question about "What color is my ???", you need to know something about an image.  As you might know, an Image is a 2D Array of "pixels".  OK, what is a pixel?  A good question -- it is a measure of light intensity, usually on a scale of 0 .. 255.  How does a pixel represent color?  If you chose an Image with the "right" kind of Pixel, then you may find that the Pixel, itself, is an array of 4 U8 values, often intensities of Red, Green, and Blue (RGB -- isn't that only 3?).

Go learn about Computer Graphics, and color representation.  Then learn about LabVIEW and how to write good LabVIEW programs.  Then put the two pieces of knowledge together.

Bob Schor

[rolfk]

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@Bob_Schor wrote:

How does a pixel represent color?  If you chose an Image with the "right" kind of Pixel, then you may find that the Pixel, itself, is an array of 4 U8 values, often intensities of Red, Green, and Blue (RGB -- isn't that only 3?).

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Yes and Windows bitmaps can be in 24-bit format, but that is not that handy to access on modern 32-bit systems. So a pixel is often stored as RGBx with the 4-th channel either being an Alpha channel (transparency, often referred to as RGBA) or simply being unused to make the access nicely 32-bit aligned. In Windows 3.1 days, memory was scarce (8MB of RAM was considered a high end machine) and every byte saved could make the difference between a program working or not. But nowadays a few MB more or less aren't that dramatic.