ios - 从 url objective-c 调整图像大小

Question

我从一个网址返回一张图片

 NSData *imageData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:Result]];

我把它存储到谷歌地图标记我想把它调整到一半大小

Answer 1

试试下面的代码:

UIImage *actualImage = [UIImage imageWithData:imageData];
UIGraphicsBeginImageContext(CGSizeMake(actualImage.size.width/2, actualImage.size.height/2);
[actualImage drawInRect:CGRectMake(0,0,actualImage.size.width/2, actualImage.size.height/2)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *smallData = UIImagePNGRepresentation(newImage);