如何使用TensorFlow操作排除图像圆之外的所有值？

import tensorflow as tf
import numpy as np
import cv2

image = cv2.imread('image.jpg')  # 替换为你的图像路径
image = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)  # 转换为RGB格式
image = cv2.resize(image, (224, 224))  # 调整图像大小为224x224
image = image / 255.0  # 归一化像素值到0-1范围

model = tf.keras.applications.MobileNetV2(weights='imagenet')

predictions = model.predict(np.expand_dims(image, axis=0))

predicted_class = tf.keras.applications.mobilenet_v2.decode_predictions(predictions, top=1)[0][0]
if predicted_class[1] != 'circle':
    print("图像中不包含圆形。")
else:
    print("图像中包含圆形。")