diff --git a/src/nvenc/nvenc_base.h b/src/nvenc/nvenc_base.h
index e81e30c2f02..c49aa4010e7 100644
--- a/src/nvenc/nvenc_base.h
+++ b/src/nvenc/nvenc_base.h
@@ -27,7 +27,7 @@ namespace nvenc {
     /**
      * @param device_type Underlying device type used by derived class.
      */
-    nvenc_base(NV_ENC_DEVICE_TYPE device_type);
+    explicit nvenc_base(NV_ENC_DEVICE_TYPE device_type);
     virtual ~nvenc_base();
 
     nvenc_base(const nvenc_base &) = delete;
diff --git a/src/nvenc/nvenc_d3d11.h b/src/nvenc/nvenc_d3d11.h
index ee6e5eac500..2d4d4fe77dc 100644
--- a/src/nvenc/nvenc_d3d11.h
+++ b/src/nvenc/nvenc_d3d11.h
@@ -23,10 +23,10 @@ namespace nvenc {
    */
   class nvenc_d3d11: public nvenc_base {
   public:
-    nvenc_d3d11(NV_ENC_DEVICE_TYPE device_type):
+    explicit nvenc_d3d11(NV_ENC_DEVICE_TYPE device_type):
         nvenc_base(device_type) {}
 
-    virtual ~nvenc_d3d11();
+    ~nvenc_d3d11();
 
     /**
      * @brief Get input surface texture.
@@ -39,6 +39,7 @@ namespace nvenc {
     bool
     init_library() override;
 
+  private:
     HMODULE dll = NULL;
   };
 
diff --git a/src/nvenc/nvenc_d3d11_native.h b/src/nvenc/nvenc_d3d11_native.h
index c7cf1ea2dec..f9d49b18631 100644
--- a/src/nvenc/nvenc_d3d11_native.h
+++ b/src/nvenc/nvenc_d3d11_native.h
@@ -20,7 +20,7 @@ namespace nvenc {
     /**
      * @param d3d_device Direct3D11 device used for encoding.
      */
-    nvenc_d3d11_native(ID3D11Device *d3d_device);
+    explicit nvenc_d3d11_native(ID3D11Device *d3d_device);
     ~nvenc_d3d11_native();
 
     ID3D11Texture2D *
diff --git a/src/nvenc/nvenc_d3d11_on_cuda.h b/src/nvenc/nvenc_d3d11_on_cuda.h
index d1ed26fa873..81114321947 100644
--- a/src/nvenc/nvenc_d3d11_on_cuda.h
+++ b/src/nvenc/nvenc_d3d11_on_cuda.h
@@ -21,7 +21,7 @@ namespace nvenc {
      * @param d3d_device Direct3D11 device that will create input surface texture.
      *                   CUDA encoding device will be derived from it.
      */
-    nvenc_d3d11_on_cuda(ID3D11Device *d3d_device);
+    explicit nvenc_d3d11_on_cuda(ID3D11Device *d3d_device);
     ~nvenc_d3d11_on_cuda();
 
     ID3D11Texture2D *
@@ -51,6 +51,7 @@ namespace nvenc {
 
       ~autopop_context();
 
+      explicit
       operator bool() const {
         return pushed_context != nullptr;
       }
diff --git a/src/video_colorspace.cpp b/src/video_colorspace.cpp
index 17f33b0ad6d..7b1ddadfe19 100644
--- a/src/video_colorspace.cpp
+++ b/src/video_colorspace.cpp
@@ -201,7 +201,7 @@ namespace video {
           Kr = 0.2627;
           Kb = 0.0593;
           break;
-      };
+      }
       double Kg = 1.0 - Kr - Kb;
 
       double y_mult, y_add;
@@ -280,7 +280,7 @@ namespace video {
       case colorspace_e::bt2020sdr:
         result = &colors[8];
         break;
-    };
+    }
 
     if (colorspace.bit_depth == 10) result += 2;
     if (colorspace.full_range) result += 1;