Python、yolo、tensorflowでruntimeerrorが出る。

yolo、tensorflow（darkflow）で以下のランタイムエラーが出てしまいます。
python、プログラム初心者のため、原因が分かりません。
検討違いな質問かもしれませんが、ご教授お願いします。

<<<<エラー>>>>
RuntimeError: out of range value for argument "y"
(RuntimeError: out of range value for argument "x"となる場合あり)
該当箇所　meters = depth_frame.get_distance(tlx+int(brx-tlx/2), bry+int(tly-bry/2))

python
1import pyrealsense2 as rs
2from darkflow.net.build import TFNet
3import cv2
4import numpy as np
5
6options = {"model": "cfg/yolo.cfg", "load": "bin/yolo.weights", "threshold": 0.1}
7tfnet = TFNet(options)
8
9class_names = ['aeroplane', 'bicycle', 'bird', 'boat', 'bottle',
10'bus', 'car', 'cat', 'chair', 'cow', 'diningtable',
11'dog', 'horse', 'motorbike', 'person', 'pottedplant',
12'sheep', 'sofa', 'train', 'tvmonitor']
13
14num_classes = len(class_names)
15class_colors = []
16for i in range(0, num_classes):
17hue = 255*i/num_classes
18col = np.zeros((1,1,3)).astype("uint8")
19col[0][0][0] = hue
20col[0][0][1] = 128
21col[0][0][2] = 255
22cvcol = cv2.cvtColor(col, cv2.COLOR_HSV2BGR)
23col = (int(cvcol[0][0][0]), int(cvcol[0][0][1]), int(cvcol[0][0][2]))
24class_colors.append(col)
25
26config = rs.config()
27config.enable_stream(rs.stream.color, 640, 480, rs.format.bgr8, 30)
28config.enable_stream(rs.stream.depth, 640, 480, rs.format.z16, 30)
29
30pipeline = rs.pipeline()
31profile = pipeline.start(config)
32
33try:
34while True:
35frames = pipeline.wait_for_frames()
36depth_frame = frames.get_depth_frame()
37color_frame = frames.get_color_frame()
38if not depth_frame or not color_frame:
39continue
40
41depth_image = np.asanyarray(depth_frame.get_data())
42color_image = np.asanyarray(color_frame.get_data())
43
44result = tfnet.return_predict(color_image)
45
46for item in result:
47tlx = item['topleft']['x']
48tly = item['topleft']['y']
49brx = item['bottomright']['x']
50bry = item['bottomright']['y']
51label = item['label']
52meters = depth_frame.get_distance(tlx+int(brx-tlx/2), bry+int(tly-bry/2))
53dep = item['confidence']
54
55if dep > 0.4:
56
57for i in class_names:
58if label == i:
59class_num = class_names.index(i)
60break
61
62box_color = (255, 128, 0)
63cv2.rectangle(color_image, (tlx, tly), (brx, bry), box_color, 2)
64
65text = label + " " + ('%.2f' % meters)
66cv2.rectangle(color_image, (tlx, tly - 15), (tlx + 100, tly + 5), box_color, -1)
67cv2.putText(color_image, text, (tlx, tly), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0,0,0), 1)
68
69cv2.imshow("Show FLAME Image", color_image)
70
71k = cv2.waitKey(10);
72if k == ord('q'):  break;
73
74finally:
75pipeline.stop()
76cv2.destroyAllWindows()
77
78