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/dnn/misc/java/src/cpp/dnn_converters.cpp

@@ -0,0 +1,102 @@
+// 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
+
+// Author: abratchik
+
+#include "dnn_converters.hpp"
+
+#define LOG_TAG "org.opencv.dnn"
+
+void Mat_to_MatShape(cv::Mat& mat, MatShape& matshape)
+{
+    matshape.clear();
+    CHECK_MAT(mat.type()==CV_32SC1 && mat.cols==1);
+    matshape = (MatShape) mat;
+}
+
+void MatShape_to_Mat(MatShape& matshape, cv::Mat& mat)
+{
+    mat = cv::Mat(matshape, true);
+}
+
+std::vector<MatShape> List_to_vector_MatShape(JNIEnv* env, jobject list)
+{
+    static jclass juArrayList       = ARRAYLIST(env);
+    jmethodID m_size       = LIST_SIZE(env, juArrayList);
+    jmethodID m_get        = LIST_GET(env, juArrayList);
+
+    static jclass jMatOfInt = MATOFINT(env);
+
+    jint len = env->CallIntMethod(list, m_size);
+    std::vector<MatShape> result;
+    result.reserve(len);
+    for (jint i=0; i<len; i++)
+    {
+        jobject element = static_cast<jobject>(env->CallObjectMethod(list, m_get, i));
+        cv::Mat& mat = *((cv::Mat*) GETNATIVEOBJ(env, jMatOfInt, element) );
+        MatShape matshape = (MatShape) mat;
+        result.push_back(matshape);
+        env->DeleteLocalRef(element);
+    }
+    return result;
+}
+
+jobject vector_Ptr_Layer_to_List(JNIEnv* env, std::vector<cv::Ptr<cv::dnn::Layer> >& vs)
+{
+    static jclass juArrayList   = ARRAYLIST(env);
+    static jmethodID m_create   = CONSTRUCTOR(env, juArrayList);
+    jmethodID m_add       = LIST_ADD(env, juArrayList);
+
+    static jclass jLayerClass = LAYER(env);
+    static jmethodID m_create_layer = LAYER_CONSTRUCTOR(env, jLayerClass);
+
+    jobject result = env->NewObject(juArrayList, m_create, vs.size());
+    for (std::vector< cv::Ptr<cv::dnn::Layer> >::iterator it = vs.begin(); it != vs.end(); ++it) {
+        jobject element = env->NewObject(jLayerClass, m_create_layer, (*it).get());
+        env->CallBooleanMethod(result, m_add, element);
+        env->DeleteLocalRef(element);
+    }
+    return result;
+}
+
+jobject vector_Target_to_List(JNIEnv* env, std::vector<cv::dnn::Target>& vs)
+{
+    static jclass juArrayList   = ARRAYLIST(env);
+    static jmethodID m_create   = CONSTRUCTOR(env, juArrayList);
+    jmethodID m_add       = LIST_ADD(env, juArrayList);
+
+    static jclass jInteger = env->FindClass("java/lang/Integer");
+    static jmethodID m_create_Integer = env->GetMethodID(jInteger, "<init>", "(I)V");
+
+    jobject result = env->NewObject(juArrayList, m_create, vs.size());
+    for (size_t i = 0; i < vs.size(); ++i)
+    {
+        jobject element = env->NewObject(jInteger, m_create_Integer, vs[i]);
+        env->CallBooleanMethod(result, m_add, element);
+        env->DeleteLocalRef(element);
+    }
+    return result;
+}
+
+std::vector<cv::Ptr<cv::dnn::Layer> > List_to_vector_Ptr_Layer(JNIEnv* env, jobject list)
+{
+    static jclass juArrayList       = ARRAYLIST(env);
+    jmethodID m_size       = LIST_SIZE(env, juArrayList);
+    jmethodID m_get        = LIST_GET(env, juArrayList);
+
+    static jclass jLayerClass = LAYER(env);
+
+    jint len = env->CallIntMethod(list, m_size);
+    std::vector< cv::Ptr<cv::dnn::Layer> > result;
+    result.reserve(len);
+    for (jint i=0; i<len; i++)
+    {
+        jobject element = static_cast<jobject>(env->CallObjectMethod(list, m_get, i));
+        cv::Ptr<cv::dnn::Layer>* layer_ptr = (cv::Ptr<cv::dnn::Layer>*) GETNATIVEOBJ(env, jLayerClass, element) ;
+        cv::Ptr<cv::dnn::Layer> layer = *(layer_ptr);
+        result.push_back(layer);
+        env->DeleteLocalRef(element);
+    }
+    return result;
+}

3rdparty/opencv-4.5.4/modules/dnn/misc/java/src/cpp/dnn_converters.hpp

@@ -0,0 +1,33 @@
+// 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
+
+// Author: abratchik
+
+#ifndef DNN_CONVERTERS_HPP
+#define	DNN_CONVERTERS_HPP
+
+#include <jni.h>
+#include "opencv_java.hpp"
+#include "opencv2/core.hpp"
+#include "opencv2/dnn/dnn.hpp"
+
+#define LAYER(ENV) static_cast<jclass>(ENV->NewGlobalRef(ENV->FindClass("org/opencv/dnn/Layer")))
+#define LAYER_CONSTRUCTOR(ENV, CLS) ENV->GetMethodID(CLS, "<init>", "(J)V")
+
+
+using namespace cv::dnn;
+
+void Mat_to_MatShape(cv::Mat& mat, MatShape& matshape);
+
+void MatShape_to_Mat(MatShape& matshape, cv::Mat& mat);
+
+std::vector<MatShape> List_to_vector_MatShape(JNIEnv* env, jobject list);
+
+jobject vector_Ptr_Layer_to_List(JNIEnv* env, std::vector<cv::Ptr<cv::dnn::Layer> >& vs);
+
+std::vector<cv::Ptr<cv::dnn::Layer> > List_to_vector_Ptr_Layer(JNIEnv* env, jobject list);
+
+jobject vector_Target_to_List(JNIEnv* env, std::vector<cv::dnn::Target>& vs);
+
+#endif	/* DNN_CONVERTERS_HPP */