面向办公室屏幕监控系统的改进型四叉树屏幕变化检测算法研究

class QuadTreeNode:
    def __init__(self, x, y, width, height, threshold=10, max_depth=8):
        self.x = x
        self.y = y
        self.width = width
        self.height = height
        self.threshold = threshold  # 变化阈值
        self.max_depth = max_depth  # 最大深度
        self.children = []  # 子节点
        self.is_leaf = True
        self.pixel_data = None  # 存储区域像素数据
        self.change_frequency = 0  # 变化频率统计
        self.last_updated = 0  # 上次更新时间戳
    def split(self):
        """将当前节点划分为四个子节点"""
        half_width = self.width // 2
        half_height = self.height // 2
        self.children = [
            QuadTreeNode(self.x, self.y, half_width, half_height, self.threshold, self.max_depth - 1),
            QuadTreeNode(self.x + half_width, self.y, half_width, half_height, self.threshold, self.max_depth - 1),
            QuadTreeNode(self.x, self.y + half_height, half_width, half_height, self.threshold, self.max_depth - 1),
            QuadTreeNode(self.x + half_width, self.y + half_height, half_width, half_height, self.threshold, self.max_depth - 1)
        ]
        self.is_leaf = False
    def update(self, new_pixels, timestamp):
        """更新节点数据并检测变化"""
        if self.is_leaf:
            # 叶节点处理
            if self.pixel_data is None:
                self.pixel_data = new_pixels
                return False
            diff = self._calculate_difference(new_pixels)
            if diff > self.threshold and self.max_depth > 0:
                # 变化超过阈值且未达到最大深度，进行分裂
                self.split()
                for child in self.children:
                    child_data = self._get_child_pixels(child)
                    child.update(child_data, timestamp)
                return True
            else:
                # 更新变化频率和时间戳
                if diff > 0:
                    self.change_frequency += 1
                    self.last_updated = timestamp
                self.pixel_data = new_pixels
                return diff > 0
        else:
            # 非叶节点处理
            has_change = False
            for child in self.children:
                child_data = self._get_child_pixels(child)
                if child.update(child_data, timestamp):
                    has_change = True
            return has_change
    def _calculate_difference(self, new_pixels):
        """计算新旧像素数据的差异"""
        if len(self.pixel_data) != len(new_pixels):
            return self.threshold + 1
        diff_count = 0
        for i in range(len(self.pixel_data)):
            if self.pixel_data[i] != new_pixels[i]:
                diff_count += 1
        return (diff_count / len(self.pixel_data)) * 100
    def _get_child_pixels(self, child):
        """从当前节点数据中提取子节点区域的像素"""
        return None
class ScreenMonitor:
    def __init__(self, width, height, threshold=10):
        self.root = QuadTreeNode(0, 0, width, height, threshold)
        self.change_history = []  # 变化历史记录
        self.timestamp = 0
    def capture_and_detect(self, screen_pixels):
        """捕获屏幕并检测变化"""
        self.timestamp += 1
        has_change = self.root.update(screen_pixels, self.timestamp)
        if has_change:
            self.change_history.append({'timestamp': self.timestamp, 'change_level': self._calculate_change_level()})
        return has_change
    def _calculate_change_level(self):
        """计算整体变化程度"""
        return sum(node.change_frequency for node in self._get_all_nodes()) / 100
    def _get_all_nodes(self):
        """获取四叉树的所有节点"""
        nodes = []
        queue = [self.root]
        while queue:
            current = queue.pop(0)
            nodes.append(current)
            if not current.is_leaf:
                queue.extend(current.children)
        return nodes
# 实际应用示例
def main():
    # 初始化屏幕监控器，假设屏幕分辨率为1920x1080
    monitor = ScreenMonitor(1920, 1080)
    # 模拟屏幕捕获循环
    for i in range(100):
        screen_pixels = capture_screen()  # 假设的屏幕捕获函数
        has_change = monitor.capture_and_detect(screen_pixels)
        if has_change:
            print(f"检测到屏幕变化 (帧 {i})")
if __name__ == "__main__":
    main()