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增加/减少UIImageView的亮度

[英]Increase/Decrease brightness of a UIImageView

Does anybody know how to change the brightness of a UIImageView in objective-C? 有人知道如何在Objective-C中更改UIImageView的亮度吗? Also, is there a way to increase/decrease the size of the UIImage ? 另外,有没有办法增加/减小UIImage的大小?

Check out the UIImage (void)drawInRect:(CGRect)rect blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha method and see what you can create. (void)drawInRect:(CGRect)rect blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alphaUIImage (void)drawInRect:(CGRect)rect blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha方法,看看可以创建什么。 Otherwise, you are going to have to do some more in depth work increasing the brightness of each pixel in HSV color space (proportionately increasing the V values). 否则,您将不得不做更多的深度工作,以增加HSV颜色空间中每个像素的亮度(成比例地增加V值)。 By blending the image with a white image using the right blend mode though, you should be able to brighten the UIImage contained within the UIImageView . 通过使用正确的混合模式将图像与白色图像混合,您应该能够使UIImageView包含的UIImage变亮。

EDIT: 编辑:

Also, as I answered in your other question, the UIImage will scale to fit the UIImageView . 另外,正如我在另一个问题中回答的那样, UIImage将缩放以适合UIImageView The image data itself will not scale, but the onscreen rendering will. 图像数据本身不会缩放,但屏幕渲染会缩放。

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