iOS裁剪图片大小改变图片尺寸图片压缩

    #pragma mark 裁剪照片  
    -(UIImage *)scaleToSize:(UIImage *)image size:(CGSize)size  
    {  
        //创建一个bitmap的context  
        //并把他设置成当前的context  
        UIGraphicsBeginImageContext(size);  
        //绘制图片的大小  
        [image drawInRect:CGRectMake(0, 0, size.width, size.height)];  
        //从当前context中创建一个改变大小后的图片  
        UIImage *endImage=UIGraphicsGetImageFromCurrentImageContext();  

        UIGraphicsEndImageContext();  
        return endImage;  
    }   

    NSData *data=UIImageJPEGRepresentation(image, 0.1);