Rendererer EX9, GDI and problem matching resolution of both

Hi again and thanks for previous help.

This time I bring you a dilema and I attached an image of it.

Here is the context:
. My camera take a video and is processed by a contour.
. Contour throw me x and y position of every contour detected which are sorrounding my object perfectly
. My objective is to do HITEST when mouse touches the detected contour and I managed to do it very well. The box in the uploaded image is my dummy object to test HITEST.
. However, my problem starts when I want my video input to watch it full screen on the EX9 renderer. Videoinput resolution is set 1024/768 and EX9 renderer is set 1024/768
. Now, to have control on the contour, the x and y output of CONTOUR where transformed to points and GDI rendered set at 1024/768
. So, here is the dilema: when I put my video input to watch full screen I scale the quads to 2 but, the contour x and y points remains not scaled hence, hitest works wrong detecting a smaller contour.

How can I scale the contour points uniformily to match the videoinput when quads are scaled to 2???

I hope I was clear enought, thanks in advance again.

Any reason in particular your using GDI?
Its performance is very bad :(
If you keep everything in dx9 then there wont be any problems! You can draw all the points as scaled down quads instead of GDI points , if you need to visualise them.

Thanks for the advice, i didn’t know about gdi and ex9 differences. Your suggestion will do the job very well.