updated

src/image_window.cpp

@@ -166,8 +166,6 @@ void ImageWindow::video_Set() {
 }
 
 void ImageWindow::video_Clr() {
-    if(ac::v_cap.isOpened()) {
+    if(playback->VideoRelease())
-        ac::v_cap.release();
         lbl_video->setText("Video closed..");
-    }
 }

src/playback_thread.cpp

@@ -29,6 +29,17 @@ Playback::Playback(QObject *parent) : QThread(parent) {
     filter_map_ex = filter_map;
 }
 
+bool Playback::VideoRelease() {
+    bool ret = false;
+    mutex.lock();
+    if(ac::v_cap.isOpened()) {
+        ac::v_cap.release();
+        ret = true;
+    }
+    mutex.unlock();
+    return ret;
+}
+
 void Playback::setCustomCycle(bool b) {
     _custom_cycle = b;
     _custom_cycle_index = 0;

src/playback_thread.h

@@ -74,6 +74,7 @@ public:
     void Play();
     void Stop();
     void Release();
+    bool VideoRelease();
     void SetFlip(bool f1, bool f2);
     void setVideo(cv::VideoCapture cap, cv::VideoWriter writer, bool record, bool record_png);
     bool setVideoCamera(std::string name, int type, int device, int res, cv::VideoWriter writer, bool record);