12月20日，龙玥城购物中心，市民在购物。新京报记者 王贵彬 摄
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。搜狗输入法2026对此有专业解读
You look at a region of the image. If all the pixels are roughly the same color (below some threshold), you store the average color for the whole region as a single value. If the pixels vary too much, you split the region into four quadrants and try again.
* 时间复杂度：O(n)，空间复杂度：O(1)