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/samples/dnn/common.py

@@ -0,0 +1,112 @@
+import sys
+import os
+import cv2 as cv
+
+
+def add_argument(zoo, parser, name, help, required=False, default=None, type=None, action=None, nargs=None):
+    if len(sys.argv) <= 1:
+        return
+
+    modelName = sys.argv[1]
+
+    if os.path.isfile(zoo):
+        fs = cv.FileStorage(zoo, cv.FILE_STORAGE_READ)
+        node = fs.getNode(modelName)
+        if not node.empty():
+            value = node.getNode(name)
+            if not value.empty():
+                if value.isReal():
+                    default = value.real()
+                elif value.isString():
+                    default = value.string()
+                elif value.isInt():
+                    default = int(value.real())
+                elif value.isSeq():
+                    default = []
+                    for i in range(value.size()):
+                        v = value.at(i)
+                        if v.isInt():
+                            default.append(int(v.real()))
+                        elif v.isReal():
+                            default.append(v.real())
+                        else:
+                            print('Unexpected value format')
+                            exit(0)
+                else:
+                    print('Unexpected field format')
+                    exit(0)
+                required = False
+
+    if action == 'store_true':
+        default = 1 if default == 'true' else (0 if default == 'false' else default)
+        assert(default is None or default == 0 or default == 1)
+        parser.add_argument('--' + name, required=required, help=help, default=bool(default),
+                            action=action)
+    else:
+        parser.add_argument('--' + name, required=required, help=help, default=default,
+                            action=action, nargs=nargs, type=type)
+
+
+def add_preproc_args(zoo, parser, sample):
+    aliases = []
+    if os.path.isfile(zoo):
+        fs = cv.FileStorage(zoo, cv.FILE_STORAGE_READ)
+        root = fs.root()
+        for name in root.keys():
+            model = root.getNode(name)
+            if model.getNode('sample').string() == sample:
+                aliases.append(name)
+
+    parser.add_argument('alias', nargs='?', choices=aliases,
+                        help='An alias name of model to extract preprocessing parameters from models.yml file.')
+    add_argument(zoo, parser, 'model', required=True,
+                 help='Path to a binary file of model contains trained weights. '
+                      'It could be a file with extensions .caffemodel (Caffe), '
+                      '.pb (TensorFlow), .t7 or .net (Torch), .weights (Darknet), .bin (OpenVINO)')
+    add_argument(zoo, parser, 'config',
+                 help='Path to a text file of model contains network configuration. '
+                      'It could be a file with extensions .prototxt (Caffe), .pbtxt or .config (TensorFlow), .cfg (Darknet), .xml (OpenVINO)')
+    add_argument(zoo, parser, 'mean', nargs='+', type=float, default=[0, 0, 0],
+                 help='Preprocess input image by subtracting mean values. '
+                      'Mean values should be in BGR order.')
+    add_argument(zoo, parser, 'scale', type=float, default=1.0,
+                 help='Preprocess input image by multiplying on a scale factor.')
+    add_argument(zoo, parser, 'width', type=int,
+                 help='Preprocess input image by resizing to a specific width.')
+    add_argument(zoo, parser, 'height', type=int,
+                 help='Preprocess input image by resizing to a specific height.')
+    add_argument(zoo, parser, 'rgb', action='store_true',
+                 help='Indicate that model works with RGB input images instead BGR ones.')
+    add_argument(zoo, parser, 'classes',
+                 help='Optional path to a text file with names of classes to label detected objects.')
+
+
+def findFile(filename):
+    if filename:
+        if os.path.exists(filename):
+            return filename
+
+        fpath = cv.samples.findFile(filename, False)
+        if fpath:
+            return fpath
+
+        samplesDataDir = os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                                      '..',
+                                      'data',
+                                      'dnn')
+        if os.path.exists(os.path.join(samplesDataDir, filename)):
+            return os.path.join(samplesDataDir, filename)
+
+        for path in ['OPENCV_DNN_TEST_DATA_PATH', 'OPENCV_TEST_DATA_PATH']:
+            try:
+                extraPath = os.environ[path]
+                absPath = os.path.join(extraPath, 'dnn', filename)
+                if os.path.exists(absPath):
+                    return absPath
+            except KeyError:
+                pass
+
+        print('File ' + filename + ' not found! Please specify a path to '
+              '/opencv_extra/testdata in OPENCV_DNN_TEST_DATA_PATH environment '
+              'variable or pass a full path to model.')
+        exit(0)