Mirror Driver Screen Capture

NTDEV
1

Hi
I have installed mirror driver and implemented the drawing functions by punting back to GDI.

My main aim is to capture the screen from the application. Iam using a named section object for this. I create a section object, map view to current process, lock pages through MDL. In the application iam using openfilemapping to map the named section object. I have few issues regarding this.

  1. The section size varies after every display change. Is using named section object a good approach? Is there a way to dynamically create section objects and communicate them to user application?

  2. Iam getting BSOD at locking pages beacuse the application process is exciting and there are still unlocked pages. Using system worker threads to run locking is a good approach?

  3. could you suggest any other clearly documented way for doing this?(if my previous appproach is wrong)

Thanks.

2

Please help me out!!

Thanks.

3

Though Mirror driver is not documented well but I believe we have discussed
most of the common problems. My suggestion is to spent some time to look
into previous threads on mirror driver issues.

I assumed your exact requirement is to share data between app and driver. I
remember some times back Tim had pointed out why can’t we use section
objects for this.

/sarbojit

On Tue, Nov 2, 2010 at 1:59 PM, wrote:

> Please help me out!!
>
> Thanks.
>
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4

Thanks sarbojit for your reply.
i have gone through the old threads. I have seen one thread where Tim mentioned its better to use mapped file. But i have not come across anything related to section objects. I will search again.

My doubt is With every change in resolution, the size of memory to be shared also varies. How can i overcome this problem? We don’t know the maximum possible size right?

5

xxxxx@gmail.com wrote:

Thanks sarbojit for your reply.
i have gone through the old threads. I have seen one thread where Tim mentioned its better to use mapped file. But i have not come across anything related to section objects. I will search again.

My doubt is With every change in resolution, the size of memory to be shared also varies. How can i overcome this problem? We don’t know the maximum possible size right?

No, but your mirror driver should gets notified on every change, so you
can allocate a new one and free the old one.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.