Display an Image that has to be resized in a UITableViewCell - iphone

Question

Hi so i currently have a small image (about 100x160) as a NSData Attribute in my CoreData model.
i display all entities in a TableView. The UIImageView in a single Cell has only a size of 50x80. just dropping the image into this frame looks a bit pebbly.
what would be the best solution to display this image in my tableViewCell? resize it on-the-fly in my cellForRowAtIndexPath? probably this will lead up my tableview to become a bit laggy.
resize it on create and save it in my coredata entity (or probably on disk)?
thank you! please leave a comment if something is unclear

Answer 1

For that you have to crop/resize the image. Following is the code to crop the image as per the required frame.
- (void)viewDidLoad
{
[super viewDidLoad];
// do something......
UIImage *img = [UIImage imageWithData:(nsdata)]; // nsdata will be your image data as you specified.
// To crop Image
UIImage *croppedImage = [self imageByCropping:img] toRect:CGRectMake(10, 10, 50, 80)];
// To resize image
UIImage *resizedImage = [self resizeImage:img width:50 height:80];
}
Crop Image:
- (UIImage*)imageByCropping:(UIImage *)imageToCrop toRect:(CGRect)rect
{
CGImageRef imageRef = CGImageCreateWithImageInRect([imageToCrop CGImage], rect);
UIImage *cropped = [UIImage imageWithCGImage:imageRef];
return cropped;
}
Resize Image:
-(UIImage *)resizeImage:(UIImage *)image width:(int)width height:(int)height
{
CGImageRef imageRef = [image CGImage];
CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(imageRef);
alphaInfo = kCGImageAlphaNoneSkipLast;
CGContextRef bitmap = CGBitmapContextCreate(NULL, width, height, CGImageGetBitsPerComponent(imageRef), 4 * width, CGImageGetColorSpace(imageRef), alphaInfo);
CGContextDrawImage(bitmap, CGRectMake(0, 0, width, height), imageRef);
CGImageRef ref = CGBitmapContextCreateImage(bitmap);
UIImage *result = [UIImage imageWithCGImage:ref];
return result;
}
You can go with either of ways.