Fix NV12 crash issue when recreate camera object

MediaClient/media/video_decoder.cpp

@@ -575,8 +575,13 @@ void CVideoDecoder::Start() {
 }
 
 void CVideoDecoder::Stop() {
-    std::lock_guard<std::recursive_mutex> lock(_mutex);
-    m_bRunning = FALSE;
+    // Atomically signal the decoder to stop WITHOUT acquiring _mutex.
+    // decode() holds _mutex while inside avcodec_send_packet / CUDA calls
+    // that can block on the nvcuda64 SRW lock for a long time.
+    // If we waited for _mutex here, Stop() would deadlock whenever a
+    // concurrent decode() is stuck waiting for a CUDA operation held by
+    // an inference thread.
+    m_bRunning.store(FALSE, std::memory_order_release);
     log_print(HT_LOG_INFO, "%s, Video decoder stopped\r\n", __FUNCTION__);
 }
 

MediaClient/media/video_decoder.h

@@ -3,6 +3,7 @@
 #include "sys_inc.h"
 #include "media_format.h"
 #include <string>
+#include <atomic>
 #include <mutex>
 #include <vector>
 extern "C"
@@ -152,7 +153,7 @@ private:
 	int     hwDecoderInit(AVCodecContext* ctx, int hwMode, int preferredGpu = -1);
 private:
 	BOOL			m_bInited;
-	BOOL			m_bRunning;
+	std::atomic<BOOL>	m_bRunning;
 	BOOL			m_bHardwareDecoderEnabled;  // Track if hardware decoder is enabled
 	bool			m_bCudaHWAccel;             // true when using AV_HWDEVICE_TYPE_CUDA
 	int				m_hwGpuIndex;               // GPU index assigned by HWDecoderPool (-1 = legacy)