handle E_NO_FRAME (no image available) differently inside background thread

XenethCamera.cpp

@@ -749,6 +749,8 @@ int XenethCamera::SnapImage()
         m_abyImage.resize(XC_GetFrameSize(m_hCamera), 0);
     }
     m_bDoCameraThread = false;
+    if (!m_byCameraTrigger)
+        m_byCameraTrigger = 1;
     m_hMutex.unlock();
     while (m_bInitialized && m_pCameraThread && !m_bDoCameraThread && m_byCameraTrigger)
         std::this_thread::sleep_for(std::chrono::milliseconds(20));
@@ -766,18 +768,23 @@ void XenethCamera::CameraThread()
         {
             m_abyImageTmp.resize(XC_GetFrameSize(m_hCamera), 0);
             ErrCode dwErr(XC_GetFrame(m_hCamera, FT_NATIVE, 0, static_cast<void*>(m_abyImageTmp.data()), static_cast<int>(m_abyImageTmp.size())));
-            m_iLastCameraResult = ConvertXenethResult(dwErr);
-            if (dwErr == I_OK)
+            int iResult(ConvertXenethResult(dwErr));
+            switch (dwErr)
             {
+                case I_OK:
+                    m_iLastCameraResult = iResult;
                     m_abyImage.swap(m_abyImageTmp);
                     if (m_byCameraTrigger > 0)
                         --m_byCameraTrigger;
-            }
-            else
-            {
+                    break;
+                case E_NO_FRAME:
+                    break;
+                default:
+                    m_iLastCameraResult = iResult;
                     LOG(("XenethCamera::CameraThread(%p) camera error %u, iResult=%d\n", this, dwErr, m_iLastCameraResult));
                     if (m_byCameraTrigger > 0)
                         m_byCameraTrigger = 1;
+                    break;
             }
         }
         m_bDoCameraThread = true;