Image original width = 100 and height = 150
Container width = 200 and height = 200
x-ratio = Container width / Image original width = 200/100 = 2.0
y-ratio = Container height / Image original height = 200/ 150 = 1.33
Selected ratio = min (x-ratio, y-ratio) = 1.33
Final Image width = Image original width * Selected Ratio = 100 * 1.33 = 133
Final Image height = Image original height * Selected Ratio = 150 * 1.33 = 200
Final Image width x height = 133 x 200 (Original width x height of image was 100 x 150)
float leftOffset = (Container width - finalImageWidth) / 2;
float topOffset = (Container width - finalImageHeight) / 2;
[self.imageView setFrame:CGRectMake(leftOffset,topOffset, finalImageWidth, finalImageHeight)];
[self.imageView setImage:@"image name"];
self.imageView.contentMode = UIViewContentModeScaleAspectFit;