30秒轻松实现TensorFlow物体检测
原创
30秒轻松实现TensorFlow物体检测
在人工智能领域,物体检测是一个非常热门的话题。TensorFlow作为一款优秀的开源机器学习框架,为我们提供了明了易用的物体检测API。接下来,我们将通过一个明了的例子,展示怎样在30秒内实现TensorFlow物体检测。
准备工作
首先,确保你已经安装了TensorFlow和TensorFlow Object Detection API。如果还没有安装,可以参考官方文档进行安装。
编写代码
下面是一段使用TensorFlow Object Detection API进行物体检测的示例代码:
import cv2
import numpy as np
import tensorflow as tf
# 加载模型
model_path = 'path/to/your/model'
detection_graph = tf.Graph()
with detection_graph.as_default():
od_graph_def = tf.GraphDef()
with tf.gfile.GFile(model_path, 'rb') as fid:
serialized_graph = fid.read()
od_graph_def.ParseFromString(serialized_graph)
tf.import_graph_def(od_graph_def, name='')
# 定义标签列表
labels = ['person', 'car', 'bus', 'truck']
# 初始化OpenCV窗口
cv2.namedWindow('object_detection', cv2.WINDOW_NORMAL)
# 处理视频流或图片
cap = cv2.VideoCapture('path/to/your/video.mp4')
with detection_graph.as_default():
with tf.Session(graph=detection_graph) as sess:
while True:
ret, image_np = cap.read()
if not ret:
break
# 获取图像的形状
image_np_expanded = np.expand_dims(image_np, axis=0)
# 获取模型输出
image_tensor = detection_graph.get_tensor_by_name('image_tensor:0')
detection_boxes = detection_graph.get_tensor_by_name('detection_boxes:0')
detection_scores = detection_graph.get_tensor_by_name('detection_scores:0')
detection_classes = detection_graph.get_tensor_by_name('detection_classes:0')
num_detections = detection_graph.get_tensor_by_name('num_detections:0')
# 运行模型
(boxes, scores, classes, num) = sess.run(
[detection_boxes, detection_scores, detection_classes, num_detections],
feed_dict={image_tensor: image_np_expanded})
# 可视化最终
for i in range(int(num[0])):
if scores[0][i] > 0.5:
box = boxes[0][i]
ymin = box[0] * image_np.shape[0]
xmin = box[1] * image_np.shape[1]
ymax = box[2] * image_np.shape[0]
xmax = box[3] * image_np.shape[1]
cv2.rectangle(image_np, (int(xmin), int(ymin)), (int(xmax), int(ymax)), (0, 0, 255), 2)
cv2.putText(image_np, labels[int(classes[0][i]) - 1], (int(xmin), int(ymin - 5)),
cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 255), 1)
cv2.imshow('object_detection', image_np)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
cap.release()
cv2.destroyAllWindows()
总结
通过以上示例,我们仅用30秒就实现了TensorFlow物体检测功能。需要注意的是,这个例子仅展示了怎样使用预训练模型进行物体检测。要实现更精确的物体检测,还需要进行数据准备、模型训练等步骤。