Resize image

CGRect rect = CGRectMake(0,0,75,75);
    UIGraphicsBeginImageContext( rect.size );
    [image drawInRect:rect];
    UIImage *picture1 = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    NSData *imageData = UIImagePNGRepresentation(picture1);
    UIImage *img=[UIImage imageWithData:imageData];