From fcf4a4d112a06f8df330abb9486c6f9d33daa03a Mon Sep 17 00:00:00 2001
From: Eric Jensen <jensen39@gmail.com>
Date: Tue, 26 Apr 2016 19:44:53 -0700
Subject: [PATCH] Prevent unnecessary locking when generating a placeholder
 image on a background thread

---
 AsyncDisplayKit/ASVideoNode.mm | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/AsyncDisplayKit/ASVideoNode.mm b/AsyncDisplayKit/ASVideoNode.mm
index fcc11e1506..7133680f3c 100644
--- a/AsyncDisplayKit/ASVideoNode.mm
+++ b/AsyncDisplayKit/ASVideoNode.mm
@@ -173,16 +173,16 @@ static NSString * const kStatus = @"status";
 - (void)imageAtTime:(CMTime)imageTime completionHandler:(void(^)(UIImage *image))completionHandler
 {
   ASPerformBlockOnBackgroundThread(^{
-    ASDN::MutexLocker l(_videoLock);
+    AVAsset *asset = self.asset;
 
     // Skip the asset image generation if we don't have any tracks available that are capable of supporting it
-    NSArray<AVAssetTrack *>* visualAssetArray = [_asset tracksWithMediaCharacteristic:AVMediaCharacteristicVisual];
+    NSArray<AVAssetTrack *>* visualAssetArray = [asset tracksWithMediaCharacteristic:AVMediaCharacteristicVisual];
     if (visualAssetArray.count == 0) {
       completionHandler(nil);
       return;
     }
 
-    AVAssetImageGenerator *previewImageGenerator = [AVAssetImageGenerator assetImageGeneratorWithAsset:_asset];
+    AVAssetImageGenerator *previewImageGenerator = [AVAssetImageGenerator assetImageGeneratorWithAsset:asset];
     previewImageGenerator.appliesPreferredTrackTransform = YES;
 
     [previewImageGenerator generateCGImagesAsynchronouslyForTimes:@[[NSValue valueWithCMTime:imageTime]]