Forced to use @autoreleasepool in order to avoid memory leak in MPMediaItemArtwork.

filter_by_artwork.m

    NSMutableArray *albumIDs = [[NSMutableArray alloc] initWithCapacity:1000];
    
    for (MPMediaItemCollection *collection in items) {
        @autoreleasepool {
            MPMediaItem *props = collection.representativeItem;
            
            NSString *albumTitle = [props valueForProperty:MPMediaItemPropertyAlbumTitle];
            NSString *artistName = [props valueForProperty:MPMediaItemPropertyAlbumArtist];
        
            MPMediaItemArtwork *artwork = [props valueForProperty:MPMediaItemPropertyArtwork];
            
            if (CGSizeEqualToSize(CGSizeZero, artwork.bounds.size)) {
                //            NSLog(@"Album doesn't have artwork: %@, %@", artistName, albumTitle);
            } else {
                //
                // It counts
                //
                [albumIDs addObject:[props valueForProperty:MPMediaItemPropertyAlbumPersistentID]];
            }
        }
    }
    
    NSLog(@"Filtered original set of %li to actual count: %li", (unsigned long)items.count, (unsigned long)albumIDs.count);

Do you remember if the memory leak in getting the MPMediaItemArtwork or in using imageWithSize: on that artwork elsewhere?