Merge branch 4.x

modules/core/include/opencv2/core/mat.hpp

@@ -1406,8 +1406,13 @@ public:
 
     When the operation mask is specified, if the Mat::create call shown above reallocates the matrix,
     the newly allocated matrix is initialized with all zeros before copying the data.
+
+    If (re)allocation of destination memory is not necessary (e.g. updating ROI), use copyAt() .
+
     @param m Destination matrix. If it does not have a proper size or type before the operation, it is
     reallocated.
+
+    @sa copyAt
      */
     void copyTo( OutputArray m ) const;
 
@@ -1420,6 +1425,30 @@ public:
     */
     void copyTo( OutputArray m, InputArray mask ) const;
 
+    /** @brief Overwrites the existing matrix
+
+    This method writes existing matrix data, just like copyTo().
+    But if it does not have a proper size or type before the operation, an exception is thrown.
+    This function is helpful to update ROI in an existing matrix.
+
+    If (re)allocation of destination memory is necessary, use copyTo() .
+
+    @param m Destination matrix.
+    If it does not have a proper size or type before the operation, an exception is thrown.
+
+    @sa copyTo
+
+     */
+    void copyAt( OutputArray m ) const;
+
+    /** @overload
+    @param m Destination matrix.
+    If it does not have a proper size or type before the operation, an exception is thrown.
+    @param mask Operation mask of the same size as \*this. Its non-zero elements indicate which matrix
+    elements need to be copied. The mask has to be of type CV_8U and can have 1 or multiple channels.
+    */
+    void copyAt( OutputArray m, InputArray mask ) const;
+
     /** @brief Converts an array to another data type with optional scaling.
 
     The method converts source pixel values to the target data type. saturate_cast\<\> is applied at

modules/core/include/opencv2/core/vsx_utils.hpp

@@ -257,8 +257,27 @@ VSX_IMPL_1VRG(vec_udword2, vec_udword2, vpopcntd, vec_popcntu)
 VSX_IMPL_1VRG(vec_udword2, vec_dword2,  vpopcntd, vec_popcntu)
 
 // converts between single and double-precision
-VSX_REDIRECT_1RG(vec_float4,  vec_double2, vec_cvfo, vec_floate)
-VSX_REDIRECT_1RG(vec_double2, vec_float4,  vec_cvfo, vec_doubleo)
+// vec_floate and vec_doubleo are available since Power10 and z14
+#if defined(__POWER10__) || (defined(__powerpc64__) && defined(__ARCH_PWR10__)
+//  Use VSX double<->float conversion instructions (if supported by the architecture)
+    VSX_REDIRECT_1RG(vec_float4,  vec_double2, vec_cvfo, vec_floate)
+    VSX_REDIRECT_1RG(vec_double2, vec_float4,  vec_cvfo, vec_doubleo)
+#else
+//  Fallback: implement vec_cvfo using scalar operations (to ensure successful linking)
+    static inline vec_float4 vec_cvfo(const vec_double2& a)
+    {
+        float r0 = static_cast<float>(reinterpret_cast<const double*>(&a)[0]);
+        float r1 = static_cast<float>(reinterpret_cast<const double*>(&a)[1]);
+        return (vec_float4){r0, 0.f, r1, 0.f};
+    }
+
+    static inline vec_double2 vec_cvfo(const vec_float4& a)
+    {
+        double r0 = static_cast<double>(reinterpret_cast<const float*>(&a)[0]);
+        double r1 = static_cast<double>(reinterpret_cast<const float*>(&a)[2]);
+        return (vec_double2){r0, r1};
+    }
+#endif
 
 // converts word and doubleword to double-precision
 #undef vec_ctd