使用Python发送DDC/CI命令以在Windows上进行监视？

Question

我希望从Windows控制我的监视器(简单的东西,如更改输入源),但无法找到从Python发送DDC/CI命令的方法...

关于图书馆或方法可能有帮助的任何线索？

Answer 1

使用Windows监视器API很容易实现.我不认为有任何Python绑定,pywin32不包含这些功能.但是,使用ctypes它们并不难.

这是一个将显示器切换为软关闭然后重新打开的示例; 它应该很容易适应改变输入源等.唯一复杂的部分是获得物理监视器的句柄:

from ctypes import windll, byref, Structure, WinError, POINTER, WINFUNCTYPE
from ctypes.wintypes import BOOL, HMONITOR, HDC, RECT, LPARAM, DWORD, BYTE, WCHAR, HANDLE


_MONITORENUMPROC = WINFUNCTYPE(BOOL, HMONITOR, HDC, POINTER(RECT), LPARAM)


class _PHYSICAL_MONITOR(Structure):
    _fields_ = [('handle', HANDLE),
                ('description', WCHAR * 128)]


def _iter_physical_monitors(close_handles=True):
    """Iterates physical monitors.

    The handles are closed automatically whenever the iterator is advanced.
    This means that the iterator should always be fully exhausted!

    If you want to keep handles e.g. because you need to store all of them and
    use them later, set `close_handles` to False and close them manually."""

    def callback(hmonitor, hdc, lprect, lparam):
        monitors.append(HMONITOR(hmonitor))
        return True

    monitors = []
    if not windll.user32.EnumDisplayMonitors(None, None, _MONITORENUMPROC(callback), None):
        raise WinError('EnumDisplayMonitors failed')

    for monitor in monitors:
        # Get physical monitor count
        count = DWORD()
        if not windll.dxva2.GetNumberOfPhysicalMonitorsFromHMONITOR(monitor, byref(count)):
            raise WinError()
        # Get physical monitor handles
        physical_array = (_PHYSICAL_MONITOR * count.value)()
        if not windll.dxva2.GetPhysicalMonitorsFromHMONITOR(monitor, count.value, physical_array):
            raise WinError()
        for physical in physical_array:
            yield physical.handle
            if close_handles:
                if not windll.dxva2.DestroyPhysicalMonitor(physical.handle):
                    raise WinError()


def set_vcp_feature(monitor, code, value):
    """Sends a DDC command to the specified monitor.

    See this link for a list of commands:
    ftp://ftp.cis.nctu.edu.tw/pub/csie/Software/X11/private/VeSaSpEcS/VESA_Document_Center_Monitor_Interface/mccsV3.pdf
    """
    if not windll.dxva2.SetVCPFeature(HANDLE(monitor), BYTE(code), DWORD(value)):
        raise WinError()


# Switch to SOFT-OFF, wait for the user to press return and then back to ON
for handle in _iter_physical_monitors():
    set_vcp_feature(handle, 0xd6, 0x04)
    raw_input()
    set_vcp_feature(handle, 0xd6, 0x01)