將日期和時間添加到通過UIImagePickerController捕獲的圖像

Question

我想將日期和時間添加到使用UIImagePickerController拍攝的圖像中。

我有一個使用控制器拍攝照片的應用程序，雖然我知道日期存儲在元數據中，但我想知道它是否可以輕鬆合併到圖像中（很像您可以將數碼相機設置爲）之類的例子如下所示：

Answer 1

注意，當ImageIO的框架導入幷包括在本纔有效。另一個條件是：

[UIImagePickerControllerMediaMetadata]使用圖像選擇器，其源類型被設置爲UIImagePickerControllerSourceTypeCamera僅當是有效的，並且只適用於靜止圖像。

這是我們從圖像中檢索日期的方式。如果您允許通過相冊選擇圖像，則此解決方案將無法使用。爲此，您需要使用ALAsset。如果您純粹使用相機（並在iOS7上運行），則此解決方案應該可以正常工作。

#import <ImageIO/ImageIO.h> 

// Ensure you've set yourself as the UIImagePickerController delegate to ensure this method is called 
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info 
{ 
    UIImage* image = info[UIImagePickerControllerOriginalImage]; 
    image = [self imageWithRenderedDateMetadata:info[UIImagePickerControllerMediaMetadata] 
             onImage:image]; 
} 

- (UIImage*)imageWithRenderedDateMetadata:(NSDictionary*)metadata onImage:(UIImage*)image 
{ 
    if (!image || !metadata) { return nil; } 

    // Get Date String 
    // Note: You can format the date string here into a more readable format if you want 
    // Here, I'll just use the YYYY:MM:DD HH:MM:SS format given 
    NSDictionary *tiffMetadata = metadata[(__bridge id)kCGImagePropertyTIFFDictionary]; 
    NSString* dateString = tiffMetaData[(__bridge id)kCGImagePropertyTIFFDateTime]; 

    UIGraphicsBeginImageContext(image.size); 

    // Draw the image into the context 
    [image drawInRect:CGRectMake(0, 0, image.size.width, image.size.height)]; 

    // Position the date in the bottom right 
    NSDictionary* attributes = @{NSFontAttributeName :[UIFont boldSystemFontOfSize:30], 
           NSStrokeColorAttributeName : [UIColor blackColor], 
           NSForegroundColorAttributeName : [UIColor yellowColor], 
           NSStrokeWidthAttributeName : @-2.0}; 

    const CGFloat dateWidth = [dateString sizeWithAttributes:attributes].width; 
    const CGFloat dateHeight = [dateString sizeWithAttributes:attributes].height; 
    const CGFloat datePadding = 25; 

    [dateString drawAtPoint:CGPointMake(image.size.width - dateWidth - datePadding, image.size.height - dateHeight - datePadding) 
      withAttributes:attributes]; 

    // Get the final image 
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); 
    UIGraphicsEndImageContext(); 

    return newImage; 
} 

你現在有一個UIImage，其中包含日期;最終的結果看起來是這樣的：