java如何从大小约为800x600的图像中获取平均RGB值

Question

How can I efficiently calculate average RGB values from a jpeg image in java? I need not get super accurate result, but i need a faster algorithm with good accuracy.

Answer 1

This sort of thing is what sampling is perfect for. If you choose the pixels you sample at random, your answer will converge on the correct answer fairly quickly. Methods like this are called Monte Carlo methods .

To illustrate this to yourself, I suggest using a sample image, and write a program to find out the true average. Now write a program to take N pixels at random uniformly over the entire image and run it for N=10, 100, 1000, 10000 and see for yourself how many you need to be accurate enough.