Possible Duplicate:
Resize UIImage with aspect ratio?
The following piece of code is resizing the image perfectly, but the problem is that it messes up the aspect ratio (resulting in a skewed image). Any pointers?
// Change image resolution (auto-resize to fit)
+ (UIImage *)scaleImage:(UIImage*)image toResolution:(int)resolution {
CGImageRef imgRef = [image CGImage];
CGFloat width = CGImageGetWidth(imgRef);
CGFloat height = CGImageGetHeight(imgRef);
CGRect bounds = CGRectMake(0, 0, width, height);
//if already at the minimum resolution, return the orginal image, otherwise scale
if (width <= resolution && height <= resolution) {
return image;
} else {
CGFloat ratio = width/height;
if (ratio > 1) {
bounds.size.width = resolution;
bounds.size.height = bounds.size.width / ratio;
} else {
bounds.size.height = resolution;
bounds.size.width = bounds.size.height * ratio;
}
}
UIGraphicsBeginImageContext(bounds.size);
[image drawInRect:CGRectMake(0.0, 0.0, bounds.size.width, bounds.size.height)];
UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageCopy;
}
I used this single line of code to create a new UIImage which is scaled. Set the scale and orientation params to achieve what you want. The first line of code just grabs the image.
// grab the original image
UIImage *originalImage = [UIImage imageNamed:@"myImage.png"];
// scaling set to 2.0 makes the image 1/2 the size.
UIImage *scaledImage =
[UIImage imageWithCGImage:[originalImage CGImage]
scale:(originalImage.scale * 2.0)
orientation:(originalImage.imageOrientation)];