x=rand()%(frame_height-2)+1
时间: 2023-11-24 09:06:35 浏览: 92
这行代码也是用于生成一个随机整数的代码,与上一个问题中的代码类似。不同的是,这里加上了一个常数 1,使得生成的随机整数的取值范围变成了 1 到 `(frame_height-2)+1`,即 1 到 `(frame_height-1)`。这往往是因为在程序中需要使用从 1 开始的索引或编号,而不是从 0 开始。
相关问题
python视频处理代码_Python+Opencv图像和视频加密的代码实现
以下是一个简单的使用Python和OpenCV实现图像和视频加密的示例代码:
```python
import cv2
import numpy as np
def encrypt(img_path, key):
# 读取图像
img = cv2.imread(img_path)
# 将图像转换为灰度图
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
# 获取图像的宽度和高度
height, width = gray.shape
# 生成随机数种子
np.random.seed(key)
# 生成与图像大小相同的随机数矩阵
rand_matrix = np.random.randint(0, 256, (height, width))
# 对图像进行异或运算
encrypted_img = cv2.bitwise_xor(gray, rand_matrix)
# 返回加密后的图像
return encrypted_img
def decrypt(encrypted_img, key):
# 获取图像的宽度和高度
height, width = encrypted_img.shape
# 生成随机数种子
np.random.seed(key)
# 生成与图像大小相同的随机数矩阵
rand_matrix = np.random.randint(0, 256, (height, width))
# 对加密图像进行异或运算
decrypted_img = cv2.bitwise_xor(encrypted_img, rand_matrix)
# 返回解密后的图像
return decrypted_img
def encrypt_video(video_path, key):
# 读取视频
cap = cv2.VideoCapture(video_path)
# 获取视频的帧率、宽度和高度
fps = int(cap.get(cv2.CAP_PROP_FPS))
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
# 创建VideoWriter对象,用于写入加密后的视频
fourcc = cv2.VideoWriter_fourcc(*'mp4v')
encrypted_video = cv2.VideoWriter('encrypted_video.mp4', fourcc, fps, (width, height), isColor=False)
# 读取视频帧并加密
while True:
ret, frame = cap.read()
if not ret:
break
# 将图像转换为灰度图
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# 加密图像
encrypted_frame = encrypt(gray, key)
# 将加密后的帧写入加密视频
encrypted_video.write(encrypted_frame)
# 释放资源
cap.release()
encrypted_video.release()
def decrypt_video(encrypted_video_path, key):
# 读取加密视频
cap = cv2.VideoCapture(encrypted_video_path)
# 获取加密视频的帧率、宽度和高度
fps = int(cap.get(cv2.CAP_PROP_FPS))
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
# 创建VideoWriter对象,用于写入解密后的视频
fourcc = cv2.VideoWriter_fourcc(*'mp4v')
decrypted_video = cv2.VideoWriter('decrypted_video.mp4', fourcc, fps, (width, height), isColor=False)
# 读取加密视频帧并解密
while True:
ret, frame = cap.read()
if not ret:
break
# 解密帧
decrypted_frame = decrypt(frame, key)
# 将解密后的帧写入解密视频
decrypted_video.write(decrypted_frame)
# 释放资源
cap.release()
decrypted_video.release()
# 测试加密解密图像
encrypted_img = encrypt('test_img.jpg', 123)
cv2.imwrite('encrypted_img.jpg', encrypted_img)
decrypted_img = decrypt(encrypted_img, 123)
cv2.imwrite('decrypted_img.jpg', decrypted_img)
# 测试加密解密视频
encrypt_video('test_video.mp4', 123)
decrypt_video('encrypted_video.mp4', 123)
```
该代码中的 `encrypt` 函数和 `decrypt` 函数分别实现了图像的加密和解密操作,使用的加密算法是将图像的每个像素值与一个随机数进行异或运算,随机数矩阵的生成使用了Numpy库中的随机数函数。
`encrypt_video` 函数和 `decrypt_video` 函数分别实现了视频的加密和解密操作,使用的方法是对视频中的每一帧进行加密或解密操作,然后将加密或解密后的帧写入加密或解密视频中。
请注意:该示例代码仅为了演示加密和解密的基本原理,实际应用中需要使用更加复杂的加密算法和密钥管理方法,以确保加密的安全性。
用java实现下列功能: 多窗口卖票情况进度显示: (1)界面上显示两个以上的窗口卖票情况,每个窗口内容包括窗口名称(NJL_2_213_A本人姓名的首字母,班级号,对应学号后三位和窗口号码),该窗口分配的票数,已卖票数(建议用进度条加数字显示); (2)所有窗口分配的票数总和等于自己学号的后三位数字,每个窗口每次卖出的票数由随机数指定; (3)启动卖票行为,由每次通过按键手工启动或通过自动按钮一键完成(建议自动),窗口的每次卖票间隔不少于1秒。
以下是用 Java 实现上述功能的代码:
```java
import javax.swing.*;
import java.awt.*;
import java.util.Random;
public class TicketSellingSystem extends JFrame {
private static final int FRAME_WIDTH = 800;
private static final int FRAME_HEIGHT = 600;
private static final int NUM_WINDOWS = 3;
private static final int MAX_TICKETS_PER_WINDOW = 50;
private Window[] windows;
private JButton manualBtn;
private JButton autoBtn;
private JProgressBar[] progressBars;
public TicketSellingSystem() {
setTitle("多窗口卖票情况进度显示");
setSize(FRAME_WIDTH, FRAME_HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Create window objects
windows = new Window[NUM_WINDOWS];
int totalTicketCount = Integer.parseInt(getStudentId().substring(5));
Random rand = new Random();
for (int i = 0; i < NUM_WINDOWS; i++) {
int windowNum = i + 1;
int maxTickets = rand.nextInt(MAX_TICKETS_PER_WINDOW) + 1;
windows[i] = new Window("NJL_2_213_A-W" + windowNum, maxTickets, totalTicketCount);
}
// Create progress bar components
progressBars = new JProgressBar[NUM_WINDOWS];
for (int i = 0; i < NUM_WINDOWS; i++) {
progressBars[i] = new JProgressBar(0, windows[i].getMaxTickets());
progressBars[i].setValue(windows[i].getSoldTickets());
progressBars[i].setStringPainted(true);
}
// Create manual and auto buttons
manualBtn = new JButton("手动卖票");
autoBtn = new JButton("自动卖票");
// Add components to frame
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(NUM_WINDOWS + 2, 1));
for (int i = 0; i < NUM_WINDOWS; i++) {
panel.add(windows[i].getLabel());
panel.add(progressBars[i]);
}
panel.add(manualBtn);
panel.add(autoBtn);
add(panel);
// Add action listeners to buttons
manualBtn.addActionListener(event -> sellTicketsManually());
autoBtn.addActionListener(event -> sellTicketsAutomatically());
}
private void sellTicketsManually() {
for (int i = 0; i < NUM_WINDOWS; i++) {
int numSold = Integer.parseInt(JOptionPane.showInputDialog(this,
"请输入窗口 " + (i + 1) + " 卖出的票数:"));
windows[i].sellTickets(numSold);
progressBars[i].setValue(windows[i].getSoldTickets());
}
}
private void sellTicketsAutomatically() {
for (int i = 0; i < NUM_WINDOWS; i++) {
int numSold = new Random().nextInt(windows[i].getMaxTickets() - windows[i].getSoldTickets() + 1);
windows[i].sellTickets(numSold);
progressBars[i].setValue(windows[i].getSoldTickets());
}
}
private String getStudentId() {
return "201912345678";
}
public static void main(String[] args) {
TicketSellingSystem system = new TicketSellingSystem();
system.setVisible(true);
}
private class Window {
private String name;
private int maxTickets;
private int soldTickets;
public Window(String name, int maxTickets, int totalTicketCount) {
this.name = name;
this.maxTickets = maxTickets;
this.soldTickets = 0;
if (maxTickets > totalTicketCount) {
this.maxTickets = totalTicketCount;
}
}
public String getName() {
return name;
}
public int getMaxTickets() {
return maxTickets;
}
public int getSoldTickets() {
return soldTickets;
}
public JLabel getLabel() {
return new JLabel(name + "(已售 " + soldTickets + " 张,共 " + maxTickets + " 张)");
}
public void sellTickets(int numSold) {
if (soldTickets + numSold <= maxTickets) {
soldTickets += numSold;
}
}
}
}
```
代码中创建了一个 `TicketSellingSystem` 类,用于显示多个窗口的卖票情况和实现手动或自动卖票。`Window` 类用于表示每个窗口的状态。卖票数量是通过随机数生成的,手动卖票时通过对话框输入。进度条和数字显示用 `JProgressBar` 组件实现。