访问库中的Burst Mode照片

I’m trying to access photos in the iOS asset library that the user has taken using Burst Mode. I’m trying using ALAssetsLibrary and filtering photos:

我正在尝试访问用户使用突发模式拍摄的iOS资源库中的照片。我正在尝试使用ALAssetsLibrary并过滤照片：

- (void)findBurstModePhotos
{
    ALAssetsFilter *allPhotos = [ALAssetsFilter allPhotos];

    ALAssetsLibrary *assetLibrary = [[ALAssetsLibrary alloc] init];

    [assetLibrary enumerateGroupsWithTypes:ALAssetsGroupAll
                                usingBlock:^(ALAssetsGroup *group,
                                             BOOL *stop) {
                                    [group setAssetsFilter:allPhotos];

                                    NSLog(@"Group: %@",
                                          [group valueForProperty:
                                           ALAssetsGroupPropertyName]);

                                    if ([group numberOfAssets] > 0) {
                                        [self evaluateGroup:group];
                                    }
                                }
                              failureBlock:^(NSError *error) {
                                  NSLog(@"Failure enumerating groups: %@",
                                        [error localizedDescription]);
                              }];
}

- (void)evaluateGroup:(ALAssetsGroup *)group
{
    [group enumerateAssetsUsingBlock:^(ALAsset *result,
                                       NSUInteger index,
                                       BOOL *stop) {
        NSLog(@"Photo date: %@", [result valueForProperty:ALAssetPropertyDate]);
    }];
}

Unfortunately, this returns Burst Mode photos as a single photo. Is there a supported way to get Burst Mode photos individually? I’d like to get each photo from a single Burst Mode session.

不幸的是，这会将Burst Mode照片作为单张照片返回。是否有支持的方式单独获得Burst Mode照片？我想从单个突发模式会话中获取每张照片。

1 个解决方案

#1

From my understandings, the Burst Mode photos will be added to the library as one by one.The ALAssetProperty type of each image will be ALAssetTypePhoto.So you can get each photo separately using the below ALAsset block. You can't retrieve only the set of Burst Mode photos at a time because there are only 7 types of ALAssetsGroupTypes and 3 kinds of ALAssetsFilters are available. None of them are dealing with Burst Mode photos.

根据我的理解，Burst Mode照片将逐个添加到库中。每个图像的ALAssetProperty类型将为ALAssetTypePhoto。因此，您可以使用下面的ALAsset块分别获取每张照片。您不能一次只检索一组Burst Mode照片，因为只有7种类型的ALAssetsGroupTypes和3种ALAssetsFilters可用。他们都没有处理Burst Mode照片。

I hope Apple will provide Burst photo filtering in the future.

我希望Apple将来会提供Burst照片过滤功能。

---------------------------- ALAssetsGroupType -------------------------------------------

ALAssetsGroupLibrary      // The Library group that includes all assets.
ALAssetsGroupAlbum        // All the albums synced from iTunes or created on the device.
ALAssetsGroupEvent        // All the events synced from iTunes.
ALAssetsGroupFaces        // All the faces albums synced from iTunes.
ALAssetsGroupSavedPhotos  // The Saved Photos album.
ALAssetsGroupPhotoStream  // The PhotoStream album.
ALAssetsGroupAll          // The same as ORing together all the available group types,with the exception that ALAssetsGroupLibrary is not included.


-------------------------- ALAssetsFilter ------------------------------------------------

+ (ALAssetsFilter *)allPhotos; // Get all photos assets in the assets group.
+ (ALAssetsFilter *)allVideos; // Get all video assets in the assets group.
+ (ALAssetsFilter *)allAssets; // Get all assets in the group.

Use the below code to get each photo separately including the Burst Mode photos,

使用以下代码分别获取每张照片，包括Burst Mode照片，

- (void)findBurstModePhotos
{
    ALAssetsLibrary *assetLibrary = [ViewController defaultAssetsLibrary];

    [assetLibrary enumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:^(ALAssetsGroup *group, BOOL *stop)
    {
    [group enumerateAssetsUsingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop) {

      if(result)
      {
        [self evaluateGroup:group];
      }

    }];

    } failureBlock:^(NSError *error) {
        NSLog(@"Error loading images %@", error);
    }];
}

- (void)evaluateGroup:(ALAssetsGroup *)group
{
    [group enumerateAssetsUsingBlock:^(ALAsset *result,
                                       NSUInteger index,
                                       BOOL *stop) {
        NSLog(@"Photo date: %@", [result valueForProperty:ALAssetPropertyDate]);
    }];
}

+ (ALAssetsLibrary *)defaultAssetsLibrary
{
    static dispatch_once_t pred = 0;
    static ALAssetsLibrary *library = nil;
    dispatch_once(&pred, ^{
        library = [[ALAssetsLibrary alloc] init];
    });
    return library;
}

Output Log:

输出日志：

Photo date: 2013-05-06 15:57:21 +0000 //non burst image.
Photo date: 2013-05-06 15:57:41 +0000 //non burst image.
Photo date: 2013-12-20 21:10:40 +0000 //burst image.
Photo date: 2013-12-20 21:10:41 +0000 //burst image.
Photo date: 2013-12-20 21:10:41 +0000 //burst image.
Photo date: 2013-12-20 21:10:41 +0000 //burst image.
Photo date: 2013-12-20 21:10:41 +0000 //burst image.
Photo date: 2013-12-20 21:10:42 +0000 //burst image.
Photo date: 2013-12-20 21:10:42 +0000 //burst image.
Photo date: 2013-12-20 21:10:42 +0000 //burst image.
Photo date: 2013-12-20 21:10:43 +0000 //burst image.
Photo date: 2013-12-20 21:10:43 +0000 //burst image.
Photo date: 2013-12-20 21:10:43 +0000 //burst image.
Photo date: 2013-12-20 21:10:44 +0000 //burst image.
Photo date: 2013-12-20 21:10:44 +0000 //burst image.
Photo date: 2013-12-20 21:10:44 +0000 //burst image.
Photo date: 2013-12-20 21:10:44 +0000 //burst image.
Photo date: 2013-12-20 21:10:45 +0000 //burst image.
Photo date: 2013-12-20 21:10:45 +0000 //burst image.
Photo date: 2013-12-20 21:10:45 +0000 //burst image.
Photo date: 2013-12-20 21:10:45 +0000 //burst image.
Photo date: 2013-12-20 21:10:46 +0000 //burst image.

Note:

注意：

If the Burst Mode photo capture camera is a part of your application,then store the ALAsset URL's when saving the captured photos to the photo gallery.You can retrieve this photo back using the saved ALAsset URL's via ALAsset library.

如果突发模式照片捕获相机是应用程序的一部分，则在将捕获的照片保存到照片库时存储ALAsset URL。您可以使用保存的ALAsset URL通过ALAsset库检索此照片。