# why does obs do BitBlt so fast?



## CPPYE (Feb 23, 2019)

when obs use dc capture to capture windwo it can reach even beyond 60 fps. when i use the same way to capture window, it can hardly to reach 60 fps. why does obs do BitBlt so fast?


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## Jim (Feb 23, 2019)

You can create a texture with GDI interop in Direct3D, which allows you to get an HDC for it, which you can blit against.


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## CPPYE (Feb 23, 2019)

thank for replying, I have found the reason.  The  bitblt was slow when you try to cpoy picture form desktop(HWND returned by GetDesktopWindow), But it's  same fast to capture other windwos except  the desktop.


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