可能是Python中最快的捕获窗口画面的方法

import time
import win32gui
import win32ui
import win32con
import cv2
import numpy as np

# 录屏调用以下方法
def videoRecordInit(fps, size, filename):
    # 创建视频编码器
    fourcc = cv2.VideoWriter_fourcc(*'mp4v')
    out = cv2.VideoWriter(filename, fourcc, fps, size)
    return out


def videoRecordWrite(out, frame):
    # 将帧写入视频流
    out.write(frame)

# 释放
def videoRecordRelease(out):
    out.release()


# 查找窗口句柄
handle = win32gui.FindWindow(None, "应用程序名")

# 获取屏幕DC
hdc = win32gui.GetDC(handle)

# 创建设备上下文DC
dc = win32ui.CreateDCFromHandle(hdc)

# 创建内存设备上下文DC
mem_dc = dc.CreateCompatibleDC()

# 获取窗口大小
left, top, right, bottom = win32gui.GetWindowRect(handle)
width = right - left
height = bottom - top

# 设置帧率
fps = 30
# 计算每帧之间的延迟时间
delay = 1 / fps

# 要录屏时
out = videoRecordInit(fps, (width, height), 'output.mp4')

# 循环遍历每个帧
while True:

    # begin = time.time()

    # 创建位图对象
    bitmap = win32ui.CreateBitmap()
    bitmap.CreateCompatibleBitmap(dc, width, height)

    # 将位图对象选入内存设备上下文DC
    mem_dc.SelectObject(bitmap)

    # 将窗口截图复制到内存设备上下文DC
    mem_dc.BitBlt((0, 0), (width, height), dc, (0, 0), win32con.SRCCOPY)

    # 将位图对象转换为numpy数组
    bmp_info = bitmap.GetInfo()
    bmp_str = bitmap.GetBitmapBits(True)
    img = np.fromstring(bmp_str, dtype='uint8')
    img = img.reshape((bmp_info['bmHeight'], bmp_info['bmWidth'], 4))

    # 转换颜色空间
    img = img[:, :, :3]

    # 录制
    videoRecordWrite(out, img)

    # 显示截图
    cv2.imshow('frame', img)

    # 若要设置帧数
    time.sleep(delay)

    # 查看速度
    # end = time.time()
    # print(end-begin)

    # 按下q键退出
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

# 释放所有对象
dc.DeleteDC()
mem_dc.DeleteDC()
win32gui.ReleaseDC(handle, hdc)
win32gui.DeleteObject(bitmap.GetHandle())
cv2.destroyAllWindows()
videoRecordRelease()