Outdoor led display quality requirement is very strict, this year after several events that led display is on fire, the safety and security of led display and detection method is very seriously. The following chip photoelectric to introduce how to do on the surface of the outdoor led display color detection.
Due to lattice characteristics of outdoor led display, the actual test found in the collection of image gray histogram bimodal distribution characteristics is very obvious. For this kind of feeling, the type of maximum variance threshold method is adopted to automatically select segmentation threshold, not only effect is good, and fast speed.
According to the principle of additive method of colorimetry, outdoor full-color led display is composed of RGB tricolor led every pixel on the screen, by controlling each pixel of a primary colors led luminous intensity, can produce all sorts of color, show the rich and colorful color image on the screen. In the CIE (international commission on illumination) rg chromaticity diagram, chromaticity coordinates, reflect the three colors in their respective relative proportion in the total tristimulus values, a set of chromaticity coordinates are expressed the same hue and saturation and brightness same different the common features of these colours.
And led large screen display on each pixel is always can find corresponding area in the image under study. Therefore, through the corresponding area of the image data RGB values to determine the chroma of the pixel.
Efficient and good detection method, which can bring full color led display screen efficient production efficiency, brightness and color correction has greatly increased the detection efficiency of outdoor led display screen and display quality, overcome in the future high brightness and color of the control of meticulous detection, provides a new direction and methods.