Method for collecting data for color measurements from a digital electronic image capturing device or system
A method for providing an intensity or brightness measurement using a digital image-capturing device comprising: selecting a target area within a field of view of the image-capturing device, the target area containing pixels; determining the brightness of pixels in the target area; accumulating the brightness values of the pixels in the target area; and determining a pixel value representative of the pixels in the target area. A device for making color measurements comprising an image-capture device, a processor or logic device, and a memory location for accumulating color data, and the processor or logic device is programmed to perform color measurements by accumulating the data for pixels located in the target area in memory, and determining a representative color value.
1. A device for making color measurements comprising:
an image-capture device,
a logic device, and
a memory location for accumulating color data, wherein the logic device is programmed to perform color measurements by:
A) starting the image-capture device to capture a frame within a preselected field of view,
B) receiving pixel data from the image-capture device,
i) determining if a current pixel is within a target area in the field of view,
ii) if the current pixel is within the target area, generating brightness values for the pixel,
iii) accumulating the brightness values only for the pixels located in the target area in the memory location,
C) determining if data for a predetermined number of frames has been collected and, if not, returning to step A) to capture the next successive frame, and, if so,
E) determining a representative color value from the brightness values of the pixels located in the target area.
2. The device of claim 1 wherein the image-capturing device is a CMOS imaging chip.
3. The device of claim 1 wherein the target area comprises a fixed region of interest.
4. The device of claim 1 wherein the target area is at least 2×2pixels an up to about 100×100 pixels.
5. The device of claim 1 wherein said device is handheld.
6. The device of claim 1 wherein said image-capture device is a digital camera or an image-capturing chip.
7. The device of claim 1 wherein the target area contains three or more color-selective pixel types and the step of accumulating the brightness values includes individually accumulating brightness values for each of the pixel types and the step of determining a representative pixel value includes determining a representative pixel value for each pixel type.
8. The device of claim 7 wherein the pixel types include red, green and 2 blue pixels.
9. The device of claim 1 wherein the target area comprises contiguous pixels within the field of view.