strange99
strange99

Reputation: 51

pixel value in UIImageView's image

I'm trying to find the value of an pixel in the image displayed in an UIImageView. getting the pixel on the display is (relatively) simple. But when the image displayed is scaled (say the orgig. image is 1200*1600) it's much more complicated because of the scaling ..

Any good advice ?

Upvotes: 1

Views: 784

Answers (1)

luvieere
luvieere

Reputation: 37494

If you're trying to get the pixel value from the original image, this question's accepted answer shows a way to get pixel values from an UIImage.

Edit:

Scaling means a loss of information, so there won't be a one-to-one mapping. One pixel on your scaled-down image corresponds to a patch of pixels in your original image, and the best that you can hope for is a lossy interval mapping from [0..scaledX] to [0..originalX] and from [0..scaledY] to [0..originalY]. An explanation on how to do such a mapping can be found in the answer to this question.

Upvotes: 1

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