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/floodfill.py

@@ -0,0 +1,88 @@
+#!/usr/bin/env python
+
+'''
+Floodfill sample.
+
+Usage:
+  floodfill.py [<image>]
+
+  Click on the image to set seed point
+
+Keys:
+  f     - toggle floating range
+  c     - toggle 4/8 connectivity
+  ESC   - exit
+'''
+
+# Python 2/3 compatibility
+from __future__ import print_function
+
+import numpy as np
+import cv2 as cv
+
+import sys
+
+class App():
+
+    def update(self, dummy=None):
+        if self.seed_pt is None:
+            cv.imshow('floodfill', self.img)
+            return
+        flooded = self.img.copy()
+        self.mask[:] = 0
+        lo = cv.getTrackbarPos('lo', 'floodfill')
+        hi = cv.getTrackbarPos('hi', 'floodfill')
+        flags = self.connectivity
+        if self.fixed_range:
+            flags |= cv.FLOODFILL_FIXED_RANGE
+        cv.floodFill(flooded, self.mask, self.seed_pt, (255, 255, 255), (lo,)*3, (hi,)*3, flags)
+        cv.circle(flooded, self.seed_pt, 2, (0, 0, 255), -1)
+        cv.imshow('floodfill', flooded)
+
+    def onmouse(self, event, x, y, flags, param):
+        if flags & cv.EVENT_FLAG_LBUTTON:
+            self.seed_pt = x, y
+            self.update()
+
+    def run(self):
+        try:
+            fn = sys.argv[1]
+        except:
+            fn = 'fruits.jpg'
+
+        self.img = cv.imread(cv.samples.findFile(fn))
+        if self.img is None:
+            print('Failed to load image file:', fn)
+            sys.exit(1)
+
+        h, w = self.img.shape[:2]
+        self.mask = np.zeros((h+2, w+2), np.uint8)
+        self.seed_pt = None
+        self.fixed_range = True
+        self.connectivity = 4
+
+        self.update()
+        cv.setMouseCallback('floodfill', self.onmouse)
+        cv.createTrackbar('lo', 'floodfill', 20, 255, self.update)
+        cv.createTrackbar('hi', 'floodfill', 20, 255, self.update)
+
+        while True:
+            ch = cv.waitKey()
+            if ch == 27:
+                break
+            if ch == ord('f'):
+                self.fixed_range = not self.fixed_range
+                print('using %s range' % ('floating', 'fixed')[self.fixed_range])
+                self.update()
+            if ch == ord('c'):
+                self.connectivity = 12-self.connectivity
+                print('connectivity =', self.connectivity)
+                self.update()
+
+        print('Done')
+
+
+if __name__ == '__main__':
+    print(__doc__)
+    App().run()
+    cv.destroyAllWindows()