把所有的像素从小到大排起来， get_percentile(0.1)就是10%位置上的灰度值。 get_percentile(0.9)就是90%位置上的灰度值。 get_percentile(0.5)就是50%位置上的灰度值，也就是中位数。 # Image Histogram Info Example # # This script computes the histogram of the image and prints it out. import sensor, image, time sensor.reset() sensor.set_pixformat(sensor.GRAYSCALE) # or RGB565. sensor.set_framesize(sensor.QVGA) sensor.skip_frames(time = 2000) sensor.set_auto_gain(False) # must be turned off for color tracking sensor.set_auto_whitebal(False) # must be turned off for color tracking clock = time.clock() while(True): clock.tick() img = sensor.snapshot() # Gets the grayscale histogram for the image into 8 bins. # Bins defaults to 256 and may be between 2 and 256. hist = img.get_histogram(bins=8) print(hist) print(hist.get_percentile(0.1)) print(clock.fps()) # You can also pass get_histogram() an "roi=" to get just the histogram of that area. # get_histogram() allows you to quickly determine the color channel information of # any any area in the image.