Get size of a UIImage (bytes length) not height and width

Question

I\'m trying to get the length of a UIImage. Not the width or height of the image, but the size of the data.

Answer 1

This following is the fastest, cleanest, most general, and least error-prone way to get the answer. In a category UIImage+MemorySize:

#import 

- (size_t) memorySize
{
  CGImageRef image = self.CGImage;
  size_t instanceSize = class_getInstanceSize(self.class);
  size_t pixmapSize = CGImageGetHeight(image) * CGImageGetBytesPerRow(image);
  size_t totalSize = instanceSize + pixmapSize;
  return totalSize;
}

Or if you only want the actual bitmap and not the UIImage instance container, then it is truly as simple as this:

- (size_t) memorySize
{
  return CGImageGetHeight(self.CGImage) * CGImageGetBytesPerRow(self.CGImage);
}