{
"shapes": [
{
"points": [
[
463.23809523809524,
380.8095238095238
],
[
550.8571428571428,
425.57142857142856
]
],
"shape_type": "rectangle",
"flags": {},
"label": "TT",
"group_id": null
},
{
"points": [
[
329.90476190476187,
397.0
],
[
378.4761904761905,
431.2857142857143
]
],
"shape_type": "rectangle",
"flags": {},
"label": "car",
"group_id": null
}
],
"imageData":......,
"imagePath": "0073.jpg",
"imageHeight": 720,
"version": "4.2.10",
"flags": {},
"imageWidth": 1280
}
其中重要的参数有shapes shape_type imagePath
shapes: 其中包含了标注的具体信息,由列表组成,每一个元素是一个字典,一个字典包含了一个标注框的相关信息;
label是标签;
points是标注的点,points的取值与shape_type相关,这里取的是rectangle即直接由矩形的对角线上两点确定一个矩形框。因此points中也只有两个点的信息,点的坐标为(x,y) ,坐标轴原点在左上角,原点向下为y正向,向右为x正向。
imagePath: 标注图片的文件名
shape_type: 记录了标记时选择的方式。
import json
import os
classes = ['car', 'Truck', 'person', 'bicycle', 'bus']
def convert(img_size, box):
x1 = box[0]
y1 = box[1]
x2 = box[2]
y2 = box[3]
x_center = ((x2 + x1) / 2 - 1) / img_size[0]
y_center = ((y2 + y1) / 2 - 1) / img_size[1]
w = (x2 - x1) / img_size[0]
h = (y2 - y1) / img_size[1]
return (x_center, y_center, w, h)
def decode_json(json_floder_path, json_name):
txt_name = '/home/zhy/Documents/智能驾驶项目/标注/txt/' + json_name[0:-5] + '.txt'
txt_file = open(txt_name, 'w')
json_path = os.path.join(json_floder_path, json_name)
data = json.load(open(json_path, 'r', encoding='utf-8'))
img_w = data['imageWidth']
img_h = data['imageHeight']
for i in data['shapes']:
if i['shape_type'] == 'rectangle':
x1 = int(i['points'][0][0])
y1 = int(i['points'][0][1])
x2 = int(i['points'][1][0])
y2 = int(i['points'][1][1])
classname = i['label']
cls_id = classes.index(classname)
bb = (x1, y1, x2, y2)
bbox = convert((img_w, img_h), bb)
txt_file.write(str(cls_id) + " " + " ".join([str(a) for a in bbox]) + '\n')
if __name__ == "__main__":
json_floder_path = '/home/zhy/Documents/智能驾驶项目/标注/json/'
json_names = os.listdir(json_floder_path)
for json_name in json_names:
decode_json(json_floder_path, json_name)