classic theme increased performance on x5-x7

[muk-as]

General information:

• OS name: Windows 7
• OS version: SP1
• OS architecture: 64 bits
• Resolutions:
  • Monitor 1: 1920x1080
• Python version: 3.8.10
• MSS version: 7.0.1

Description of the warning/error

if disable windows aero(use classic theme) than performance will increased on x5-x7

Full message

with mss.mss() as sct:

	bbox = (0, 0, 1280, 720)
	log.console_time('MSS_start')
	for i in range(1000):
		screenshot = np.array(sct.grab(bbox), copy=False, order='C')
	log.console_time('MSS1_end')
	#print(screenshot.flags)
	for i in range(1000):
		screenshot = np.ascontiguousarray(sct.grab(bbox))
	log.console_time('MSS2_end')
	#print(screenshot.flags)
	for i in range(1000):
		screenshot = np.array(sct.grab(bbox))
	log.console_time('MSS3_end')

with aero

2023-01-15 21:06:37,407 | window_capture.py      ->             <module>():127 | MainThread | INFO   : [!t] MSS_start _ default _ exec_time: 2.430 ms
2023-01-15 21:06:55,844 | window_capture.py      ->             <module>():130 | MainThread | INFO   : [!t] MSS1_end _ default _ exec_time: 18437 ms
2023-01-15 21:07:14,344 | window_capture.py      ->             <module>():134 | MainThread | INFO   : [!t] MSS2_end _ default _ exec_time: 18499 ms
2023-01-15 21:07:32,763 | window_capture.py      ->             <module>():138 | MainThread | INFO   : [!t] MSS3_end _ default _ exec_time: 18418 ms

with classic theme

2023-01-15 21:08:02,949 | window_capture.py      ->             <module>():127 | MainThread | INFO   : [!t] MSS_start _ default _ exec_time: 2.263 ms
2023-01-15 21:08:05,410 | window_capture.py      ->             <module>():130 | MainThread | INFO   : [!t] MSS1_end _ default _ exec_time: 2460. ms
2023-01-15 21:08:07,895 | window_capture.py      ->             <module>():134 | MainThread | INFO   : [!t] MSS2_end _ default _ exec_time: 2484. ms
2023-01-15 21:08:11,611 | window_capture.py      ->             <module>():138 | MainThread | INFO   : [!t] MSS3_end _ default _ exec_time: 3715. ms

try tests on win10, win11 and other python versions and type results

[CTPaHHuK-HEbA]

windows 10 doesn't have classic theme

[BoboTiG]

My naive guess would be that Aero is using a lot of blur, and so there are less way to compress pixels. It would be interesting to track the MSS code to see where the time is spent.

[muk-as]

right now im using this code. its a little faster than mss on my requestions.
and it's doesn't care about aero. same results with classic and with aero themes

self.hwnd = win32gui.FindWindow(None, self.window_name)
def _screenshot_win(self): # cpu_avg 2.8 on 50ms sleep | 1.4 on 100ms | 1.15 on 100ms with openCV cvtColor
	# get the window image data
	wDC = win32gui.GetWindowDC(self.hwnd)
	dcObj = win32ui.CreateDCFromHandle(wDC)
	cDC = dcObj.CreateCompatibleDC()
	dataBitMap = win32ui.CreateBitmap()
	dataBitMap.CreateCompatibleBitmap(dcObj, self.w, self.h)
	cDC.SelectObject(dataBitMap)
	cDC.BitBlt((0, 0), (self.w, self.h), dcObj, (0, 0), win32con.SRCCOPY)

	# convert the raw data into a format opencv can read
	signedIntsArray = dataBitMap.GetBitmapBits(True)
	img = np.frombuffer(signedIntsArray, dtype='uint8')
	img.shape = (self.h, self.w, 4)

	# free resources
	dcObj.DeleteDC()
	cDC.DeleteDC()
	win32gui.ReleaseDC(self.hwnd, wDC)
	win32gui.DeleteObject(dataBitMap.GetHandle())

	img = cv.cvtColor(img, cv.COLOR_BGRA2BGR) # drops alpha + save C_CONTIGUOUS flag
	return img

[CTPaHHuK-HEbA]

My naive guess would be that Aero is using a lot of blur, and so there are less way to compress pixels. It would be interesting to track the MSS code to see where the time is spent.

I think, first source code, only copying from video memory, no compression

same results with classic and with aero themes
self.hwnd = win32gui.FindWindow(None, self.window_name)

You sample capture only inside the window, not desktop?
Maybe : same results with classic and with aero themes

My tests:
Windows 7
Monitor 60Hz
Using display styles for buttons and windows
Other switch - no effect

On: ~ 20 fps
Off ~ 80 fps

Regresion in this function:
self.gdi32.BitBlt()

[BoboTiG]

Thanks for the clue @CTPaHHuK-HEbA.
It seems unrelated to MSS but how Windows works under the wood: https://stackoverflow.com/q/7154574/1117028.

I do not close the issue because I hope there is some hidden API, or whatever we could leverage, to improve slightly the situation. I'm open to suggestions too :)