Python暢遊電腦視覺海洋：從影像分類到目標偵測的精彩之旅

# 导入必要的库
import numpy as np
import matplotlib.pyplot as plt
from sklearn.model_selection import train_test_split
from sklearn.linear_model import LoGISticRegression

# 加载和预处理图像数据
data = np.load("data.npy")
labels = np.load("labels.npy")
data = data.reshape((data.shape[0], -1))
data = data.astype("float32") / 255.0

# 将数据分成训练集和测试集
X_train, X_test, y_train, y_test = train_test_split(data, labels, test_size=0.2)

# 训练逻辑回归分类器
classifier = LogisticRegression(max_iter=1000)
classifier.fit(X_train, y_train)

# 评估分类器
score = classifier.score(X_test, y_test)
print("准确率：", score)

# 预测新图像
image = np.load("new_image.npy")
image = image.reshape((1, -1))
image = image.astype("float32") / 255.0
prediction = classifier.predict(image)
print("预测标签：", prediction)

import numpy as np
import cv2

# 加载并预处理图像
image = cv2.imread("image.png")
image = cv2.resize(image, (640, 480))

# 创建目标检测器
detector = cv2.dnn.readNetFromCaffe("deploy.prototxt.txt", "res10_300x300_ssd_iter_140000.caffemodel")

# 检测图像中的对象
blob = cv2.dnn.blobFromImage(image, 0.007843, (300, 300), 127.5)
detector.setInput(blob)
detections = detector.forward()

# 绘制检测结果
for i in range(0, detections.shape[2]):
confidence = detections[0, 0, i, 2]
if confidence > 0.5:
x1 = int(detections[0, 0, i, 3] * image.shape[1])
y1 = int(detections[0, 0, i, 4] * image.shape[0])
x2 = int(detections[0, 0, i, 5] * image.shape[1])
y2 = int(detections[0, 0, i, 6] * image.shape[0])
cv2.rectangle(image, (x1, y1), (x2, y2), (0, 255, 0), 2)

# 显示结果图像
cv2.imshow("检测结果", image)
cv2.waiTKEy(0)
cv2.destroyAllwindows()