Re: BitBlt() function performance question - C / C++ / MFC Discussion Boards

How do I know my dual display in span mode in windows xp?

cedricvictor26-Jan-15 16:49

26-Jan-15 16:49

Dear all:

I have two touch screens and dual monitor, I try to match touch screen for each monitor in windows xp.

I can do it in mirror mode and extended mode, but failed in span
mode.

I use the EnumDisplayMonitor to get the monitor count, but the monitor count is 1 in span mode.

How do I know my dual diplay in span mode and get the monitor count?

best regards, Victor

modified 28-Jan-15 21:59pm.

Win8.1 UEFI block WINIO?

ICEric25-Jan-15 22:32

ICEric

25-Jan-15 22:32

Hi All,

I am writing a program to control some I/O card under Win8.1 environment, however, initialisation winio always fail. There is no problem under WinXP or Win7, so I guess it is caused by Win8.1 UEFI blocked the WINIO.

Is there anyone who can give me a solution?

Thanks
Eric

Re: Win8.1 UEFI block WINIO?

Richard MacCutchan25-Jan-15 23:25

Richard MacCutchan

25-Jan-15 23:25

It is unlikely that anyone can give a solution, unless you provide a lot more information. Where does the failure occur, what are the conditions, what error status or message do you see ... ?

Re: Win8.1 UEFI block WINIO?

ICEric26-Jan-15 14:47

ICEric

26-Jan-15 14:47

When I perform
DWORD dwMemVal;
bool bResult;
HANDLE hPhysicalMemory;
PBYTE pbLinAddr;

// Call InitializeWinIo to initialize the WinIo library.

ShutdownWinIo();

bResult = InitializeWinIo();

the bResult keeps 0, so I cannot initialize WinIO

However, I tried to create a virtual machine with WinXP installed, using the same sourecode without any problem. Thus, I guess it is caused by Win8.1 UEFI which protect the BIOS controlled by WinIO.

Would there be anyone who can help me to fix this problem? Thanks a lot for any help.

Re: Win8.1 UEFI block WINIO?

Randor 26-Jan-15 15:24

Randor

26-Jan-15 15:24

Hi,

Your WINIO device driver needs to be signed.

Driver Signing Policy[^]

Best Wishes,
-David Delaune

Re: Win8.1 UEFI block WINIO?

ICEric27-Jan-15 5:13

ICEric

27-Jan-15 5:13

Hi

I tried to put the same program in Win8.0 and it works without the need to sign-up WINIO.
I would like to know what is the different between Win8 and 8.1?

Thanks

BitBlt() function performance question

econy23-Jan-15 7:55

econy

23-Jan-15 7:55

Hi, in a windows CE platform, I tested BitBlt() function,
I found it will take about 400 millisecdons to do:

MemBoard.CreateCompatibleDC(&dc);
bmpDashBoard.LoadBitmap( IDB_SCREEN_IMP );
pOldBmp = (CBitmap*)Memboard.SelectObject(&bmpBoard);
...
MemDC.CreateCompatibleDC(dc);
..
MemDC.BitBlt(0,0, 800,600,&Memboard, 0, 0, SRCCOPY);

is there anyway to speed up BitBlt() function?

Re: BitBlt() function performance question

C^hris L^osinger23-Jan-15 10:39

C^hris L^osinger

23-Jan-15 10:39

are you saying it takes 400ms to do all of that, or just the BitBlt?

because you can do the LoadBitmap ahead of time and just keep the CBitmap around for when you need it.

image processing toolkits | batch image processing

Re: BitBlt() function performance question

econy23-Jan-15 13:38

econy

23-Jan-15 13:38

I can't get precise time, but, with old BitBlt(), not a 800*600 bitmap,
I set tick count array in program, tkCount[15]-tkCount[14] = tkCount[14] - tkCount[13] ... = tkCount[1] - tkCount[0] = 170 ms around.

Then I use new BitBlt() to load 800*600 bitmap, it gives 400ms around.

So I should say it added 230 ms.

Old BitBlt() just transport about 1/5 or 1/6 part of 800*600 bitmap.

I expected to use a 800*600(the screen area) memory DC to hold all parts changes, then BitBlt() to screen.

Now that 800*600 tooks so much time, I don't think a double buffer technique is helpful.

Re: BitBlt() function performance question

C^hris L^osinger27-Jan-15 1:59

C^hris L^osinger

27-Jan-15 1:59

what do you mean "old" and "new" BitBlt ?

image processing toolkits | batch image processing

Re: BitBlt() function performance question

Albert Holguin25-Jan-15 8:19

Albert Holguin

25-Jan-15 8:19

I doubt it's the BitBlt slowing you down that much. You probably shouldn't be loading a bitmap every single time, load it once and keep it in memory for better results.

Re: BitBlt() function performance question

econy26-Jan-15 3:50

econy

26-Jan-15 3:50

Yes, I know redraw picture is a time-costing work.
But, the application need to update picture with the real-time data.

Re: BitBlt() function performance question

Albert Holguin26-Jan-15 4:00

Albert Holguin

26-Jan-15 4:00

I do real-time drawing... bitblt() is your friend, you're probably doing something else that's slow.

Re: BitBlt() function performance question

econy26-Jan-15 5:07

econy

26-Jan-15 5:07

The background picture is 800*600, 24 color depth, so it is about 1.44 MB.
Did you think the picture size would affect the BitBlt() speed?

Re: BitBlt() function performance question

Albert Holguin26-Jan-15 6:34

Albert Holguin

26-Jan-15 6:34

I'm sure it would... but not to the extent that your numbers reflect. You're doing something else wrong (or... more precisely, you're doing something else that's slowing the process down).

Re: BitBlt() function performance question

enhzflep25-Jan-15 14:26

enhzflep

25-Jan-15 14:26

How much time does it take to do the other 4 lines?

Re: BitBlt() function performance question

econy26-Jan-15 3:51

econy

26-Jan-15 3:51

It seems 1-3 ms, based on tickcount() result

Re: BitBlt() function performance question

_Flaviu25-Jan-15 21:12

_Flaviu

25-Jan-15 21:12

Do you handled CDC::SetStretchBltMode[^] ? Depend on this settings, you will have rendering speed or render quality ...

Re: BitBlt() function performance question

econy26-Jan-15 3:48

econy

26-Jan-15 3:48

Thanks, I will read descriptions of this function

Re: BitBlt() function performance question

Nitin K. Kawale26-Jan-15 17:36

Nitin K. Kawale

26-Jan-15 17:36

Hey why not using DirectX ,it uses Double buffering algorithm

Re: BitBlt() function performance question

econy27-Jan-15 7:18

econy

27-Jan-15 7:18

Thanks,image without dirctx components inside

Re: BitBlt() function performance question

Mike Nordell2-Feb-15 9:44

Mike Nordell

2-Feb-15 9:44

If it's indeed the blit sucking that much time, prime suspect would be format conversion.

Check out GetObject() for BITMAP, to see what the format of src and dest are. I'm willing to bet 3 lines of C++ that they are different. Smile | :)

modified 2-Feb-15 18:09pm.

CompatibleDC parameter question

econy23-Jan-15 4:36

econy

23-Jan-15 4:36

Hi, I have a question, situation like:

C++

void funcA() 
{
   CDC	MemDC;
   CDC	*pDC ;
   pDC = GetDC(); 
   memDC.CreateCompatibleDC(pDC);
   
   funcB(memDC);
}

void funcB(CDC *pDC) 
{
   HDC hdc;
   HDC hdcMem;

   hdc = pDC->m_hDC;
   hdcMem = CreateCompatibleDC(hdc);
   ...
   BitBlt(hdc,0,0,100,100,hdcMem,0,0,SRCCOPY);
}

I think this BitBlt() will copy hdcMem to MemDC(in FuncA), right? just want to confirm it.

Re: CompatibleDC parameter question

Richard MacCutchan23-Jan-15 5:35

Richard MacCutchan

23-Jan-15 5:35

What exactly are you trying to achieve?

Re: CompatibleDC parameter question

econy23-Jan-15 5:52

econy

23-Jan-15 5:52

I want funcB draw picture on it's own temporary DC, then paste on funcA's memory DC, and FuncA paste the whole funcA's DC to screen.

Like:
B -> A
c -> A
...
x -> A

and A -> screen.

And I had another question, I have a big bitmap, represent the screen, many parts of the bitmap need to update independently and frequently.

is it a good idea using one memory DC to hold
all part's temporary DC, then post the whole memory DC to screen? that is, the double buffering technique.

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