def __get_window_class_name(hwnd, max_nof_bytes_class_name=32):
"""
:param hwnd: window handle
:param max_nof_bytes_class_name: [description], defaults to 32
:param max_nof_bytes_class_name: int, optional
:return: Name of the window class that the specified window belongs to.
"""
windows_class_name_buffer = ctypes.create_unicode_buffer(
max_nof_bytes_class_name)
assert_win(
ctypes.windll.user32.GetClassNameW(hwnd, windows_class_name_buffer,
max_nof_bytes_class_name))
return windows_class_name_buffer.value
def __get_window_handle(window_name=None, window_class_name=None):
"""Searches for the window handle matching the window name
or window class name.
Uses
https://docs.microsoft.com/en-us/windows/desktop/api/winuser/nf-winuser-findwindoww
:param window_name: [description], defaults to None
:param window_name: [type], optional
:param window_class_name: [description], defaults to None
:param window_class_name: [type], optional
:return: matched window handle
"""
window_handle = ctypes.windll.user32.FindWindowW(
ctypes.wintypes.LPCWSTR(window_class_name),
ctypes.wintypes.LPCWSTR(window_name))
assert_win(window_handle)
return window_handle
def __get_window_handle_information():
"""Retrieves information such as window_handle, process_id and thread_id.
:return: a named tuple with window_handle, process_id and thread_id
"""
information = list()
def EnumWindowsProc(hwnd, lParam):
information.append(__get_window_handle_information_for(hwnd))
#To continue enumeration, the callback function must return TRUE;
#to stop enumeration, it must return FALSE.
return True
assert_win(
ctypes.windll.user32.EnumWindows(
ctypes.WINFUNCTYPE(ctypes.wintypes.BOOL, ctypes.wintypes.HWND,
ctypes.wintypes.LPARAM)(EnumWindowsProc), 0))
return information
def get_windowshot(window_handle):
"""Get an RGB screen capture of a window
:param window_handle: Handle to the window that will be screenshot.
:type window_handle: ctypes.wintypes.HWND
:return: RGB-screenshot
:rtype: numpy.array
"""
with Context(
window_handle,
constructor=ctypes.windll.user32.GetWindowDC,
destructor=lambda hDC, hWnd=window_handle: ctypes.windll.user32.ReleaseDC(hWnd, hDC)) as ctx_window_device_context:
with Context(
ctx_window_device_context(), constructor=ctypes.windll.gdi32.CreateCompatibleDC,
destructor=ctypes.windll.gdi32.DeleteDC) as ctx_memory_device_context_handle:
window_rect = ctypes.wintypes.RECT()
assert_win(ctypes.windll.user32.GetWindowRect(window_handle, ctypes.byref(window_rect)))
width = window_rect.right - window_rect.left
height = window_rect.bottom - window_rect.top
with Context(
ctx_window_device_context(),
width,
height,
constructor=ctypes.windll.gdi32.CreateCompatibleBitmap,
destructor=ctypes.windll.gdi32.DeleteObject) as ctx_graphics_device_interface_bitmap_handle:
logging.debug('Contexts created.')
graphics_device_interface_previously_selected_bitmap_handle = ctypes.windll.gdi32.SelectObject(
ctx_memory_device_context_handle(), ctx_graphics_device_interface_bitmap_handle())
assert_win(graphics_device_interface_previously_selected_bitmap_handle)
assert graphics_device_interface_previously_selected_bitmap_handle != ctypes.wintypes.HANDLE(0xFFFFFFFF)
assert_win(ctypes.windll.user32.PrintWindow(window_handle, ctx_memory_device_context_handle(), 0))
#[https://msdn.microsoft.com/sv-se/02f8ed65-8fed-4dda-9b94-7343a0cfa8c1,
# https://msdn.microsoft.com/en-us/library/dd183376(v=vs.85).aspx]
bitmap_info = BITMAPINFO()
bitmap_info.bmiHeader.biSize = ctypes.sizeof(BITMAPINFOHEADER)
bitmap_info.bmiHeader.biWidth = width
#Top-down image [https://msdn.microsoft.com/sv-se/library/ms787796.aspx,
# https://docs.microsoft.com/sv-se/windows/desktop/api/wingdi/nf-wingdi-getdibits]
bitmap_info.bmiHeader.biHeight = -height
bitmap_info.bmiHeader.biPlanes = 1
#"The bitmap has a maximum of 2^32 colors. If the biCompression member of the BITMAPINFOHEADER is BI_RGB, the bmiColors
# member of BITMAPINFO is NULL. Each DWORD in the bitmap array represents the relative intensities of blue, green, and
# red for a pixel. The value for blue is in the least significant 8 bits, followed by 8 bits each for green and red.
# The high byte in each DWORD is not used."
# => Do not set bmiColors in ctypes?
bitmap_info.bmiHeader.biBitCount = 32
#"BI_RGB An uncompressed format." [wingdi.h]
bitmap_info.bmiHeader.biCompression = 0
#"This may be set to zero for BI_RGB bitmaps."
bitmap_info.bmiHeader.biSizeImage = 0
#0? 10 pixels/millimeter = 10000 pixels/m? -- no idea if there is a "correct" value
bitmap_info.bmiHeader.biXPelsPerMeter = 0
bitmap_info.bmiHeader.biYPelsPerMeter = 0
#"If this value is zero, the bitmap uses the maximum number of colors corresponding to the value of the biBitCount
# member for the compression mode specified by biCompression."
bitmap_info.bmiHeader.biClrUsed = 0
#"If this value is zero, all colors are required."
bitmap_info.bmiHeader.biClrImportant = 0
data = ctypes.create_string_buffer(width * height * 4)
#[https://docs.microsoft.com/sv-se/windows/desktop/api/wingdi/nf-wingdi-getdibits]
#DIB_RGB_COLORS = 0 [wingdi.h]
nof_scanlines = ctypes.windll.gdi32.GetDIBits(ctx_memory_device_context_handle(),
ctx_graphics_device_interface_bitmap_handle(), 0, height, data, bitmap_info,
0)
assert_win(nof_scanlines == height)
#Convert BGRX to RGB
#https://stackoverflow.com/a/37421379
return np.frombuffer(data, dtype='uint8').reshape(height, width, 4)[..., :3][..., ::-1]
def __exit__(self, *exc_args): if self.destructor: self.destruct = self.destructor(self.construct) assert_win(self.destruct_ok(self.destruct)) return False
def __enter__(self): if self.constructor: self.construct = self.constructor(*self.args) assert_win(self.construct_ok(self.construct)) return self
def __get_cursor_pos():
function = ctypes.windll.user32.GetCursorPos
function.restype = ctypes.wintypes.BOOL
point = ctypes.wintypes.POINT()
assert_win(function(ctypes.byref(point)))
return point
def __window_from_point(point):
function = ctypes.windll.user32.WindowFromPoint
function.restype = ctypes.wintypes.HANDLE
return assert_win(function(point))