如果我的窗口处于32位颜色深度模式,则以下代码将从窗口获取一个漂亮的PIL图像:
def image_grab_native(window):
hwnd = win32gui.GetDesktopWindow()
left, top, right, bot = get_rect(window)
w = right - left
h = bot - top
hwndDC = win32gui.GetWindowDC(hwnd)
mfcDC = win32ui.CreateDCFromHandle(hwndDC)
saveDC = mfcDC.CreateCompatibleDC()
saveBitMap = win32ui.CreateBitmap()
saveBitMap.CreateCompatibleBitmap(mfcDC, w, h)
saveDC.SelectObject(saveBitMap)
saveDC.BitBlt((0, 0), (w, h), mfcDC, (left, top), win32con.SRCCOPY)
bmpinfo = saveBitMap.GetInfo()
bmpstr = saveBitMap.GetBitmapBits(True)
im = Image.frombuffer(
'RGB',
(bmpinfo['bmWidth'], bmpinfo['bmHeight']),
bmpstr, 'raw', 'BGRX', 0, 1)
win32gui.DeleteObject(saveBitMap.GetHandle())
saveDC.DeleteDC()
mfcDC.DeleteDC()
win32gui.ReleaseDC(hwnd, hwndDC)
return im
但是,在16位模式下运行时,我得到错误:
>>> image_grab_native(win)
Traceback (most recent call last):
File "<pyshell#3>", line 1, in <module>
image_grab_native(win)
File "C:\claudiu\bumhunter\finderbot\ezpoker\utils\win32.py", line 204, in image_grab_native
bmpstr, 'raw', 'BGRX', 0, 1)
File "c:\python25\lib\site-packages\PIL\Image.py", line 1808, in frombuffer
return apply(fromstring, (mode, size, data, decoder_name, args))
File "c:\python25\lib\site-packages\PIL\Image.py", line 1747, in fromstring
im.fromstring(data, decoder_name, args)
File "c:\python25\lib\site-packages\PIL\Image.py", line 575, in fromstring
raise ValueError("not enough image data")
ValueError: not enough image data
我应该如何形成
frombuffer
调用以16位模式工作?另外,如何使此函数在任何位深度模式下工作,而不是说必须将其作为参数传递?
更新:来自
this question
我知道我必须使用“BGR;16”而不是“BGRX”作为第二模式参数。它拍摄正确的图片,或者指定步幅,或者不指定步幅。问题是某些值上的像素值稍有偏差:
x y native ImageGrab
280 0 (213, 210, 205) (214, 211, 206)
280 20 (156, 153, 156) (156, 154, 156)
280 40 (213, 210, 205) (214, 211, 206)
300 0 (213, 210, 205) (214, 211, 206)
只是从同一窗口获取的值的样本。屏幕截图看起来和肉眼一模一样,但我必须做一些像素操作。。我想使用本机方法的另一个原因是,它有点快,而且在具有双监视器的虚拟机中运行时性能更好。。(是的,我知道这很随机的复杂)。
