调用相册怎么设置剪裁－b

//创建一个相册控制器
    UIImagePickerController *pc = [[UIImagePickerController alloc] init];

    //图片来源
//    UIImagePickerControllerSourceTypePhotoLibrary  //相册库
//    UIImagePickerControllerSourceTypeCamera      //相机 (模拟器使用相机会崩溃,真机可以)
//    UIImagePickerControllerSourceTypeSavedPhotosAlbum 照片库
    pc.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

    //是否允许编辑图片
    pc.allowsEditing = YES;

    pc.delegate = self;  //设置代理  <UINavigationControllerDelegate,UIImagePickerControllerDelegate>  //相册控制器要遵守两个协议

    //把相册控制器 present 出来
    [self presentViewController:pc animated:YES completion:nil];

相册代理里面可以设置
#pragma mark - 相册控制器的代理方法
//选择图片完成后调用
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    NSLog(@"%@",info);  //得到字典

    //保存编辑后的图片 ,在字典里面有信息
    self.imageView.image = info[@"UIImagePickerControllerEditedImage"];

//    data 转成image
    //UIImage imageWithData:<#(NSData *)#>

//    image(.PNG) 转成data
    //UIImagePNGRepresentation(<#UIImage *image#>)
//    .jpg 转成data
    //参数2. 压缩系数,0 - 1.0
    NSData *dataOriginal = UIImageJPEGRepresentation(self.imageView.image, 1.0);
    NSData *dataEdited = UIImageJPEGRepresentation(self.imageView.image, 0.3);

    NSLog(@"%@",NSHomeDirectory());

    //把原始的图片保存到沙盒
    [dataOriginal writeToFile:[NSString stringWithFormat:@"%@/Library/1.jpg",NSHomeDirectory()] atomically:YES];
    //把编辑过的图片也保存进去 方便对比 (编辑了会压缩,压缩过后的图片所占外存更小,放大会模糊)
    [dataEdited writeToFile:[NSString stringWithFormat:@"%@/Library/2.jpg",NSHomeDirectory()] atomically:YES];

    //返回
    [picker dismissViewControllerAnimated:YES completion:nil];
}