🚀 go-pugleaf

Thanks for your help ! It's getting more clear for me.

Christophe

Bob Gonder wrote:

> Christophe MINETTI wrote:
>
> >Yes it turns around 70 msec to get a "stable" image.
> >As I have to wait at least 70 msec
> >and then wait the next synchro top of the camera, I am decreasing the acquisition
> >frequency. If I decrease those 70 msec, than for sure I will get a mix of two
> >frames.
>
> If you go to DirectDraw or DirectX you might be able to pick up a bit
> by drawing the next frame on a hidden page while you are waiting for
> the LCD pixels to turn on.
> http://msdn2.microsoft.com/en-us/library/ms792915.aspx
>
> Pre-Paint to hidden page
> Loop:
> WaitForBlank    less than 17ms (end of last scanline)
> Flip page
> Paint to hidden page
> WaitForBlank    17ms
> Wait for LCD    5 to 20 ms depending on LCD
> Click Camera
> repeat Loop.
>
> So, if you have a gamer's LCD, and your camera can sync up and capture
> within 12 ms, then you could get 30 fps
> With a regular LCD, you would be looking at a maximum of 20 fps.
> And if the camera is slow, 15 fps.
>
> > I was hoping (but I think there is no way to get it) to know by any way when
> >the LCD has been completely refreshed ...
>
> No, there is no way, as that has to do with the speed of the crystals,
> and not the electronics.