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/python/tutorial_code/imgProc/threshold/threshold.py

@@ -0,0 +1,54 @@
+from __future__ import print_function
+import cv2 as cv
+import argparse
+
+max_value = 255
+max_type = 4
+max_binary_value = 255
+trackbar_type = 'Type: \n 0: Binary \n 1: Binary Inverted \n 2: Truncate \n 3: To Zero \n 4: To Zero Inverted'
+trackbar_value = 'Value'
+window_name = 'Threshold Demo'
+
+## [Threshold_Demo]
+def Threshold_Demo(val):
+    #0: Binary
+    #1: Binary Inverted
+    #2: Threshold Truncated
+    #3: Threshold to Zero
+    #4: Threshold to Zero Inverted
+    threshold_type = cv.getTrackbarPos(trackbar_type, window_name)
+    threshold_value = cv.getTrackbarPos(trackbar_value, window_name)
+    _, dst = cv.threshold(src_gray, threshold_value, max_binary_value, threshold_type )
+    cv.imshow(window_name, dst)
+## [Threshold_Demo]
+
+parser = argparse.ArgumentParser(description='Code for Basic Thresholding Operations tutorial.')
+parser.add_argument('--input', help='Path to input image.', default='stuff.jpg')
+args = parser.parse_args()
+
+## [load]
+# Load an image
+src = cv.imread(cv.samples.findFile(args.input))
+if src is None:
+    print('Could not open or find the image: ', args.input)
+    exit(0)
+# Convert the image to Gray
+src_gray = cv.cvtColor(src, cv.COLOR_BGR2GRAY)
+## [load]
+
+## [window]
+# Create a window to display results
+cv.namedWindow(window_name)
+## [window]
+
+## [trackbar]
+# Create Trackbar to choose type of Threshold
+cv.createTrackbar(trackbar_type, window_name , 3, max_type, Threshold_Demo)
+# Create Trackbar to choose Threshold value
+cv.createTrackbar(trackbar_value, window_name , 0, max_value, Threshold_Demo)
+## [trackbar]
+
+# Call the function to initialize
+Threshold_Demo(0)
+# Wait until user finishes program
+cv.waitKey()