translation.en: When Kareem moves his head to the right, you will see this blue activity there; it represents regions where the contrast is increasing in the image, that's where it's going from dark to light.
translation.zh: 当Kareem把头转向右边， 你能看见那儿的蓝色活动区域， 它代表图像中对比加强的区域， 这一区域由暗变明。