Reduce UIImage size to a manageable size (reduce bytes)

Question

I want to reduce the number of bytes of an image captured by the device, since i believe the _imageScaledToSize does not reduce the number of bytes of the pictu

Answer 1

When you say 'physical size', are you talking about a print? Because you can just change the printer page size.

Are you talking about the number of pixels used to capture the image? As in, if you have a pixel array of 3000x2000, and you only want 150x150, then you can crop the images. At the time of capture, if you have a scientific imager, then you can just set the area that will be captured. The camera driver would include instructions for that. If you want to capture 3000x2000 in 1500x1000, you can try to bin the image, if that's what you need.

Or, you can use resampling post-capture in order to make the image smaller. One such algorithm is bicubic resampling, also linear resampling-- there are many variations.

I'm thinking this last is what you're most interested in... in which case, check out this Wikipedia page on the algorithm. Or, you can go to FreeImage and get a library that will read in the image and can also resize images.