Update python wrapper

wrappers/python/samples/util/cv_painter.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+# Copyright 2018 Slightech Co., Ltd. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# pylint: disable=missing-docstring
+
+import cv2
+
+
+FONT_FACE = cv2.FONT_HERSHEY_SIMPLEX
+FONT_SCALE = 1
+FONT_COLOR = (255, 255, 255)
+THICKNESS = 1
+
+
+class Gravity(object):  # pylint: disable=no-init
+  TOP_LEFT = 1
+  TOP_RIGHT = 2
+  BOTTOM_LEFT = 3
+  BOTTOM_RIGHT = 4
+
+
+def draw_text(img, text, gravity, margin=10, offset_x=0, offset_y=0):
+  h, w = img.shape[:2]  # pylint: disable=invalid-name
+
+  # getTextSize, result: ((width, height), baseline)
+  x, y = cv2.getTextSize(text, FONT_FACE, FONT_SCALE, THICKNESS)[0]
+
+  org = {
+      Gravity.TOP_LEFT:     (margin, margin + y),
+      Gravity.TOP_RIGHT:    (w - margin - x, margin + y),
+      Gravity.BOTTOM_LEFT:  (margin, h - margin),
+      Gravity.BOTTOM_RIGHT: (w - margin - x, h - margin),
+  }.get(gravity, (margin, margin + y))
+
+  org = (org[0] + offset_x, org[1] + offset_y)
+
+  # putText(img, text, org, fontFace, fontScale, color, thickness, lineType)
+  cv2.putText(img, text, org, FONT_FACE, FONT_SCALE,
+              FONT_COLOR, THICKNESS, cv2.LINE_AA)