From 3d19de2b58a5c1e02cd46a2e92ca6ac1cc0ca031 Mon Sep 17 00:00:00 2001
From: David Wolever <david@wolever.net>
Date: Tue, 2 Aug 2016 17:52:02 -0400
Subject: [PATCH] Fix crash on double-stop of CvVideoCamera

---
 modules/videoio/src/cap_ios_video_camera.mm | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/modules/videoio/src/cap_ios_video_camera.mm b/modules/videoio/src/cap_ios_video_camera.mm
index 1ae70e2987..8d483092c5 100644
--- a/modules/videoio/src/cap_ios_video_camera.mm
+++ b/modules/videoio/src/cap_ios_video_camera.mm
@@ -100,6 +100,10 @@ static CGFloat DegreesToRadians(CGFloat degrees) {return degrees * M_PI / 180;}
 
 - (void)start;
 {
+    if (self.running == YES) {
+        return;
+    }
+
     recordingCountDown = 10;
     [super start];
 
@@ -118,6 +122,10 @@ static CGFloat DegreesToRadians(CGFloat degrees) {return degrees * M_PI / 180;}
 
 - (void)stop;
 {
+    if (self.running == NO) {
+        return;
+    }
+
     [super stop];
 
     self.videoDataOutput = nil;