In above, we see there are couples of black spots in the mask, that is the noise. Mask = cv2.inRange(hsv, lower_range, upper_range) Hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV) The code then waits for the user to hit the ‘Esc’ button which will quit it and destroy all the windows to cleanup. If you want to understand what 0xFF means in the code read this. cv2.imshow('image', img)įinally, we can show the original and mask image side by side to see the difference. The areas that match will an image set to the mask variable. In this case, we are checking through the hsv image, and checking for colors that are between the lower-range and upper-range. The mask simply represent a specific part of the image. Here we are actually creating a mask with the specified blue. mask = cv2.inRange(hsv, lower_range, upper_range) To find these limit we can use the range-detector script in the imutils library. Now we define the upper and lower limit of the blue we want to detect.

Now we have convert the image to an hsv image because hsv helps to differentiate intensity from color. hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV) In third line, I’m importing imutils module, which helps in resizing images and finding the range of colors. In above line of code, first two lines handle all the imports. Just open your favourite python text editor or IDE and let’s get started. Now that we have got the colors image, we can start the fun part. So let’s first download the image with which we will be working with, The saturation is the intensity of the color, where a saturation of 0 represent 0 and a saturation of 255 is maximum intensity.Value will tell how bright or dark the color is. Instead, it uses hue, which is the color or shade of the pixel. However, unlike RGB, HSV does not use the primary color to represent a pixel. With HSV, a pixel is also represented by 3 parameters, but it is instead Hue, Saturation and Value. For example, if we were to show a pure blue pixel on-screen, then the R value would be 0, the G value would be 0, and the B value would be 255.īelow are a few more examples of colors in RGB: Color Each component can take a value between 0 and 255, where the tuple (0, 0, 0) represents black and (255, 255, 255) represents white. RGB basically describes color as a tuple of three components. RGB(Red, Green, Blue) and HSV (Hue, Saturation, Value). Instead of going for each color, we’ll discuss most common color-space we use. We represent colors on a computers by color-space or color models which basically describes range of colors as tuples of numbers. In this tutorial we’ll be doing basic color detection in openCv with python. For many people, image processing may seem like a scary and daunting task but it is not as hard as many people thought it is.

Binary editor gauge resizing