feat: 切换后端至PaddleOCR-NCNN，切换工程为CMake

1.项目后端整体迁移至PaddleOCR-NCNN算法，已通过基本的兼容性测试
2.工程改为使用CMake组织，后续为了更好地兼容第三方库，不再提供QMake工程
3.重整权利声明文件，重整代码工程，确保最小化侵权风险

Log: 切换后端至PaddleOCR-NCNN，切换工程为CMake
Change-Id: I4d5d2c5d37505a4a24b389b1a4c5d12f17bfa38c

3rdparty/opencv-4.5.4/modules/gapi/test/gapi_smoke_test.cpp

@@ -0,0 +1,97 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html.
+//
+// Copyright (C) 2018 Intel Corporation
+
+
+#include "test_precomp.hpp"
+
+namespace opencv_test
+{
+
+TEST(GAPI, Mat_Create_NoLink)
+{
+    cv::Mat m1;
+    cv::Mat m2 = m1;
+    m2.create(32, 32, CV_8U);
+
+    EXPECT_NE(m1.rows, m2.rows);
+    EXPECT_NE(m1.cols, m2.cols);
+    EXPECT_NE(m1.data, m2.data);
+}
+
+TEST(GAPI, Mat_Recreate)
+{
+    cv::Mat m1 = cv::Mat::zeros(480, 640, CV_8U);
+    m1.at<uchar>(0, 0) = 128;
+    cv::Mat m2 = m1;
+
+    EXPECT_EQ(m1.rows, m2.rows);
+    EXPECT_EQ(m1.cols, m2.cols);
+    EXPECT_EQ(m1.data, m2.data);
+    EXPECT_EQ(m1.at<uchar>(0, 0), m2.at<uchar>(0, 0));
+
+    // Calling "create" with the same meta is NOOP - both m1 and m2 are the same
+    m1.create(480, 640, CV_8U);
+    EXPECT_EQ(m1.rows, m2.rows);
+    EXPECT_EQ(m1.cols, m2.cols);
+    EXPECT_EQ(m1.data, m2.data);
+    EXPECT_EQ(m1.at<uchar>(0, 0), m2.at<uchar>(0, 0));
+
+    // Calling "create" on m2 with different meta doesn't update original m1
+    // Now m1 and m2 are distinct
+    m2.create(720, 1280, CV_8U);
+    m2.at<uchar>(0, 0) = 64; // Initialize 0,0 element since m2 is a new buffer
+    EXPECT_NE(m1.rows, m2.rows);
+    EXPECT_NE(m1.cols, m2.cols);
+    EXPECT_NE(m1.data, m2.data);
+    EXPECT_NE(m1.at<uchar>(0, 0), m2.at<uchar>(0, 0));
+
+    // What if a Mat is created from handle?
+    uchar data[] = {
+        32, 0, 0,
+         0, 0, 0,
+         0, 0, 0
+    };
+    cv::Mat m3(3, 3, CV_8U, data);
+    cv::Mat m4 = m3;
+    EXPECT_EQ(m3.rows, m4.rows);
+    EXPECT_EQ(m3.cols, m4.cols);
+    EXPECT_EQ(m3.data, m4.data);
+    EXPECT_EQ(data, m3.data);
+    EXPECT_EQ(data, m4.data);
+    EXPECT_EQ(m3.at<uchar>(0, 0), m4.at<uchar>(0, 0));
+
+    // cv::Mat::create must be NOOP if we don't change the meta,
+    // even if the original mat is created from handle.
+    m4.create(3, 3, CV_8U);
+    EXPECT_EQ(m3.rows, m4.rows);
+    EXPECT_EQ(m3.cols, m4.cols);
+    EXPECT_EQ(m3.data, m4.data);
+    EXPECT_EQ(data, m3.data);
+    EXPECT_EQ(data, m4.data);
+    EXPECT_EQ(m3.at<uchar>(0, 0), m4.at<uchar>(0, 0));
+}
+
+TEST(GAPI, EmptyOutMat)
+{
+    cv::Mat in_mat = cv::Mat(480, 640, CV_8U, cv::Scalar(64));
+
+    cv::GComputation cc([]()
+    {
+        cv::GMat in;
+        cv::GMat out = in + in;
+        return cv::GComputation(in, out);
+    });
+
+    cv::Mat out;
+    cc.apply(in_mat, out);
+
+    EXPECT_EQ(640, out.cols);
+    EXPECT_EQ(480, out.rows);
+    EXPECT_EQ(CV_8U, out.type());
+    EXPECT_EQ(0, cvtest::norm(out, (in_mat+in_mat), NORM_INF));
+}
+
+}