拍照后编辑图像

Question

我目前正在制作一个 iphone 应用程序，用户可以在其中拍照或从相册中选择它，然后在图像上放置一个叠加层。然后用户可以缩放、旋转和保存图像。目前，我可以拍照，或者选择一张作为相册。至于叠加层，我只是使用了 UIImageView 并将其放置在 Interface builder 的层次结构之上。对于相机，我正在使用以下代码：

-(IBAction)getPhoto:(id)sender  {

// Create an image picker controller
UIImagePickerController * imagePicker = [[UIImagePickerController alloc] init];


if((UIButton *) sender == choosePhotoBtn)   {
    // Set source to photo albums
    imagePicker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
}

else    {
    // Set source to camera
    imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
    imagePicker.showsCameraControls = YES;
}

// Delegate is self
imagePicker.delegate = self;

    // Allow editing of image
    imagePicker.allowsEditing = YES;

    // Show image picker
    [self presentModalViewController:imagePicker animated: YES];
}

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info   {
// Dismiss modalviewcontroller
[picker dismissModalViewControllerAnimated:YES];

// Displaying image to the imageView
imageView.image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

// Access the uncropped image from info dictionary
UIImage * image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];


// Save Image
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);

[picker release];
}

我现在遇到的问题是在拍摄后编辑照片。如何自定义相机以使其具有这样的行为？：

1. 选择使用相机或从相册中获取照片

2. 选择后，叠加图像将变为我在脸部放置“圆圈”的图像，照片将像面具一样位于下方。此视图还可以全屏编辑。您可以旋转、缩放和移动图像，直到单击完成。

我已阅读手册中的这一部分，但我似乎无法理解如何使用它。 http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIImagePickerController_Class/UIImagePickerController/UIImagePickerController.html

希望有人能指出正确的方向。

非常感谢。 -Hakimo

Answer 1

有一种方法不需要过多地更改代码：

- (IBAction)takePicture:(id)sender {
UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
    [imagePicker setSourceType:UIImagePickerControllerSourceTypeCamera];
} else {
    [imagePicker setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];
}

[imagePicker setAllowsEditing:YES];
[imagePicker setDelegate:self];

//place image picker on the screen
[self presentViewController:imagePicker animated:YES completion:nil];
}

如果要使用编辑后的图片，请将“UIImagePickerControllerOriginalImage”改为“UIImagePickerControllerEditedImage”即可！

Answer 2

对于 Q1，是否可以实现一个操作表，以便用户可以选择使用相册中的照片或拍摄新照片。？操作表功能类似于以下内容：

-(void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
    if (buttonIndex == 0) {
        picker = [[UIImagePickerController alloc]init];
        picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
        picker.delegate = self;
        [self presentModalViewController:picker animated:YES];
        [picker release];
    }

    else if (buttonIndex == 1) {
        if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
            picker = [[UIImagePickerController alloc]init];
            picker.sourceType = UIImagePickerControllerSourceTypeCamera;
            picker.allowsEditing = YES;
            picker.delegate = self;
            [self presentModalViewController:picker animated:YES];
            [picker release];
        }
        else {
            UIAlertView *noCameraMsg = [[UIAlertView alloc] initWithTitle:@"no camera on this phone" message:@"" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
            [noCameraMsg show];
            [noCameraMsg release];

        }


}