Introduces yuv420p(nv12) to rgb and bgr color conversion

modules/gapi/include/opencv2/gapi/imgproc.hpp

@@ -114,6 +114,34 @@ namespace imgproc {
         }
     };
 
+    G_TYPED_KERNEL(GNV12toRGB, <GMat(GMat, GMat)>, "org.opencv.imgproc.colorconvert.nv12torgb") {
+        static GMatDesc outMeta(GMatDesc in_y, GMatDesc in_uv) {
+            GAPI_Assert(in_y.chan == 1);
+            GAPI_Assert(in_uv.chan == 2);
+            GAPI_Assert(in_y.depth == CV_8U);
+            GAPI_Assert(in_uv.depth == CV_8U);
+            GAPI_Assert(in_uv.size.width % 2 == 0);
+            GAPI_Assert(in_uv.size.height % 2 == 0);
+            GAPI_Assert(in_y.size.width == 2 * in_uv.size.width);
+            GAPI_Assert(in_y.size.height == 2 * in_uv.size.height);
+            return in_y.withType(CV_8U, 3); // type will be CV_8UC3;
+        }
+    };
+
+    G_TYPED_KERNEL(GNV12toBGR, <GMat(GMat, GMat)>, "org.opencv.imgproc.colorconvert.nv12tobgr") {
+        static GMatDesc outMeta(GMatDesc in_y, GMatDesc in_uv) {
+            GAPI_Assert(in_y.chan == 1);
+            GAPI_Assert(in_uv.chan == 2);
+            GAPI_Assert(in_y.depth == CV_8U);
+            GAPI_Assert(in_uv.depth == CV_8U);
+            GAPI_Assert(in_uv.size.width % 2 == 0);
+            GAPI_Assert(in_uv.size.height % 2 == 0);
+            GAPI_Assert(in_y.size.width == 2 * in_uv.size.width);
+            GAPI_Assert(in_y.size.height == 2 * in_uv.size.height);
+            return in_y.withType(CV_8U, 3); // type will be CV_8UC3;
+        }
+    };
+
     G_TYPED_KERNEL(GRGB2Lab, <GMat(GMat)>, "org.opencv.imgproc.colorconvert.rgb2lab") {
         static GMatDesc outMeta(GMatDesc in) {
             return in; // type still remains CV_8UC3;
@@ -728,6 +756,36 @@ Output image must be 8-bit unsigned 3-channel image @ref CV_8UC3.
 @sa RGB2Lab, RGB2YUV
 */
 GAPI_EXPORTS GMat YUV2RGB(const GMat& src);
+
+/** @brief Converts an image from NV12 (YUV420p) color space to RGB.
+The function converts an input image from NV12 color space to RGB.
+The conventional ranges for Y, U, and V channel values are 0 to 255.
+
+Output image must be 8-bit unsigned 3-channel image @ref CV_8UC3.
+
+@note Function textual ID is "org.opencv.imgproc.colorconvert.nv12torgb"
+
+@param src_y input image: 8-bit unsigned 1-channel image @ref CV_8UC1.
+@param src_uv input image: 8-bit unsigned 2-channel image @ref CV_8UC2.
+
+@sa YUV2RGB, NV12toBGR
+*/
+GAPI_EXPORTS GMat NV12toRGB(const GMat& src_y, const GMat& src_uv);
+
+/** @brief Converts an image from NV12 (YUV420p) color space to BGR.
+The function converts an input image from NV12 color space to RGB.
+The conventional ranges for Y, U, and V channel values are 0 to 255.
+
+Output image must be 8-bit unsigned 3-channel image @ref CV_8UC3.
+
+@note Function textual ID is "org.opencv.imgproc.colorconvert.nv12tobgr"
+
+@param src_y input image: 8-bit unsigned 1-channel image @ref CV_8UC1.
+@param src_uv input image: 8-bit unsigned 2-channel image @ref CV_8UC2.
+
+@sa YUV2BGR, NV12toRGB
+*/
+GAPI_EXPORTS GMat NV12toBGR(const GMat& src_y, const GMat& src_uv);
 //! @} gapi_colorconvert
 } //namespace gapi
 } //namespace cv

modules/gapi/src/api/kernels_imgproc.cpp

@@ -142,6 +142,16 @@ GMat YUV2RGB(const GMat& src)
     return imgproc::GYUV2RGB::on(src);
 }
 
+GMat NV12toRGB(const GMat& src_y, const GMat& src_uv)
+{
+    return imgproc::GNV12toRGB::on(src_y, src_uv);
+}
+
+GMat NV12toBGR(const GMat& src_y, const GMat& src_uv)
+{
+    return imgproc::GNV12toBGR::on(src_y, src_uv);
+}
+
 GMat RGB2Lab(const GMat& src)
 {
     return imgproc::GRGB2Lab::on(src);

modules/gapi/src/backends/cpu/gcpuimgproc.cpp

@@ -194,6 +194,22 @@ GAPI_OCV_KERNEL(GCPUYUV2RGB, cv::gapi::imgproc::GYUV2RGB)
     }
 };
 
+GAPI_OCV_KERNEL(GCPUNV12toRGB, cv::gapi::imgproc::GNV12toRGB)
+{
+    static void run(const cv::Mat& in_y, const cv::Mat& in_uv, cv::Mat &out)
+    {
+        cv::cvtColorTwoPlane(in_y, in_uv, out, cv::COLOR_YUV2RGB_NV12);
+    }
+};
+
+GAPI_OCV_KERNEL(GCPUNV12toBGR, cv::gapi::imgproc::GNV12toBGR)
+{
+    static void run(const cv::Mat& in_y, const cv::Mat& in_uv, cv::Mat &out)
+    {
+        cv::cvtColorTwoPlane(in_y, in_uv, out, cv::COLOR_YUV2BGR_NV12);
+    }
+};
+
 GAPI_OCV_KERNEL(GCPURGB2Lab, cv::gapi::imgproc::GRGB2Lab)
 {
     static void run(const cv::Mat& in, cv::Mat &out)
@@ -277,6 +293,8 @@ cv::gapi::GKernelPackage cv::gapi::imgproc::cpu::kernels()
         , GCPUEqualizeHist
         , GCPURGB2YUV
         , GCPUYUV2RGB
+        , GCPUNV12toRGB
+        , GCPUNV12toBGR
         , GCPURGB2Lab
         , GCPUBGR2LUV
         , GCPUBGR2YUV

modules/gapi/test/common/gapi_imgproc_tests.hpp

@@ -33,6 +33,8 @@ struct RGB2GrayTest : public  TestParams<std::tuple<compare_f,cv::Size,bool,cv::
 struct BGR2GrayTest : public TestParams<std::tuple<compare_f,cv::Size,bool,cv::GCompileArgs>> {};
 struct RGB2YUVTest : public TestParams<std::tuple<compare_f,cv::Size,bool,cv::GCompileArgs>> {};
 struct YUV2RGBTest : public TestParams<std::tuple<compare_f,cv::Size,bool,cv::GCompileArgs>> {};
+struct NV12toRGBTest : public TestParams<std::tuple<compare_f,cv::Size,cv::GCompileArgs>> {};
+struct NV12toBGRTest : public TestParams<std::tuple<compare_f,cv::Size,cv::GCompileArgs>> {};
 struct RGB2LabTest : public TestParams<std::tuple<compare_f,cv::Size,bool,cv::GCompileArgs>> {};
 struct BGR2LUVTest : public TestParams<std::tuple<compare_f,cv::Size,bool,cv::GCompileArgs>> {};
 struct LUV2BGRTest : public TestParams<std::tuple<compare_f,cv::Size,bool,cv::GCompileArgs>> {};

modules/gapi/test/common/gapi_imgproc_tests_inl.hpp

@@ -548,6 +548,66 @@ TEST_P(YUV2RGBTest, AccuracyTest)
     }
 }
 
+TEST_P(NV12toRGBTest, AccuracyTest)
+{
+    compare_f cmpF;
+    cv::Size sz;
+    cv::GCompileArgs compile_args;
+    std::tie(cmpF, sz, compile_args) = GetParam();
+
+    initMatsRandN(CV_8UC1, sz, CV_8UC3);
+
+    // G-API code //////////////////////////////////////////////////////////////
+    cv::GMat in_y;
+    cv::GMat in_uv;
+    auto out = cv::gapi::NV12toRGB(in_y, in_uv);
+
+    // Additional mat for uv
+    cv::Mat in_mat_uv(cv::Size(sz.width / 2, sz.height / 2), CV_8UC2);
+
+    cv::GComputation c(cv::GIn(in_y, in_uv), cv::GOut(out));
+    c.apply(cv::gin(in_mat1, in_mat_uv), cv::gout(out_mat_gapi), std::move(compile_args));
+    // OpenCV code /////////////////////////////////////////////////////////////
+    {
+        cv::cvtColorTwoPlane(in_mat1, in_mat_uv, out_mat_ocv, cv::COLOR_YUV2RGB_NV12);
+    }
+    // Comparison //////////////////////////////////////////////////////////////
+    {
+        EXPECT_TRUE(cmpF(out_mat_gapi, out_mat_ocv));
+        EXPECT_EQ(out_mat_gapi.size(), sz);
+    }
+}
+
+TEST_P(NV12toBGRTest, AccuracyTest)
+{
+    compare_f cmpF;
+    cv::Size sz;
+    cv::GCompileArgs compile_args;
+    std::tie(cmpF, sz, compile_args) = GetParam();
+
+    initMatsRandN(CV_8UC1, sz, CV_8UC3);
+
+    // G-API code //////////////////////////////////////////////////////////////
+    cv::GMat in_y;
+    cv::GMat in_uv;
+    auto out = cv::gapi::NV12toBGR(in_y, in_uv);
+
+    // Additional mat for uv
+    cv::Mat in_mat_uv(cv::Size(sz.width / 2, sz.height / 2), CV_8UC2);
+
+    cv::GComputation c(cv::GIn(in_y, in_uv), cv::GOut(out));
+    c.apply(cv::gin(in_mat1, in_mat_uv), cv::gout(out_mat_gapi), std::move(compile_args));
+    // OpenCV code /////////////////////////////////////////////////////////////
+    {
+        cv::cvtColorTwoPlane(in_mat1, in_mat_uv, out_mat_ocv, cv::COLOR_YUV2BGR_NV12);
+    }
+    // Comparison //////////////////////////////////////////////////////////////
+    {
+        EXPECT_TRUE(cmpF(out_mat_gapi, out_mat_ocv));
+        EXPECT_EQ(out_mat_gapi.size(), sz);
+    }
+}
+
 TEST_P(RGB2LabTest, AccuracyTest)
 {
     auto param = GetParam();

modules/gapi/test/cpu/gapi_imgproc_tests_cpu.cpp

@@ -224,6 +224,18 @@ INSTANTIATE_TEST_CASE_P(YUV2RGBTestCPU, YUV2RGBTest,
                             /*init output matrices or not*/ testing::Bool(),
                                 Values(cv::compile_args(IMGPROC_CPU))));
 
+INSTANTIATE_TEST_CASE_P(NV12toRGBTestCPU, NV12toRGBTest,
+                        Combine(Values(AbsExact().to_compare_f()),
+                                Values(cv::Size(1280, 720),
+                                       cv::Size(640, 480)),
+                                Values(cv::compile_args(IMGPROC_CPU))));
+
+INSTANTIATE_TEST_CASE_P(NV12toBGRTestCPU, NV12toBGRTest,
+                        Combine(Values(AbsExact().to_compare_f()),
+                                Values(cv::Size(1280, 720),
+                                       cv::Size(640, 480)),
+                                Values(cv::compile_args(IMGPROC_CPU))));
+
 INSTANTIATE_TEST_CASE_P(RGB2LabTestCPU, RGB2LabTest,
                         Combine(Values(AbsExact().to_compare_f()),
                                 Values(cv::Size(1280, 720),