Re: Bitmap and clipboard - C / C++ / MFC Discussion Boards

#realJSOP4-Oct-01 6:44

4-Oct-01 6:44

I'm capturing a frame from a video stream. The data is being captured (I've verified that) as a 24-bit image. Part of the data being "captured" is the contents of the BITMAPINFOHEADER struct (again, this struct contains viable data).

I want to take this image and store it to the clipboard as a DIB.

Why doesn't this code work?

BITMAPINFO bmi;
memset(&bmi, 0, sizeof(BITMAPINFO));
bmi.bmiHeader = cb.bih; // the cb struct is populated by the capture callback

HDC hMemDC = CreateCompatibleDC(NULL);
HBITMAP hBitmap = CreateDIBitmap(hMemDC, &bmi.bmiHeader, CBM_INIT, cb.pBuffer, &bmi, DIB_RGB_COLORS);

if (OpenClipboard(NULL))
{
   EmptyClipboard();
   if (!SetClipboardData(CF_DIB, hBitmap))
   {
      // show error message
   }
   CloseClipboard();
}

It always says that the hBitmap handle is invalid when I try to call SetClipboardData(). The hBitmap isn't NULL.

Re: Bitmap and clipboard

C^hris L^osinger4-Oct-01 7:00

C^hris L^osinger

4-Oct-01 7:00

try using a real DC (instead of NULL) in your CreateCompatibleDC call. i find that these CreateCompatible things often only work with a real DC.

-c

------------------------------
Smaller Animals Software, Inc.
http://www.smalleranimals.com

Re: Bitmap and clipboard

#realJSOP4-Oct-01 7:18

#realJSOP

4-Oct-01 7:18

I tried the CreateCompatibleDC method, and the results are the same.

The SDK documentation says that if you pass NULL to CreateCompatibleDC, you get a screen DC. Why isn't that good enough?

Confused | :confused:

Re: Bitmap and clipboard

C^hris L^osinger4-Oct-01 7:29

C^hris L^osinger

4-Oct-01 7:29

that might be true..

i only metion that becaseu i find that doing something like this:

CDC memDC;
memDC.CreateCompatibleDC(pRealDC);
CBitmap memBMP;
memBMP.CreateCompatibleBitmap(memDC, ...);

will often fail (i get a monochrome bitmap or something equally perverse). To make it work I have to use pRealDC in the CreateCompatibleBitmap call. using the 'compatible' DC screws things up.

so, as a rule, i always use a real DC (from GetDC(NULL), or a paint DC or a CClientDC) in these functions.

just a thought.

also, when i copy DIBs to the clipboard, i do it like this:

HGLOBAL CISImage::MakeClipboardDIB()
{
   HGLOBAL hDIB = MakeDIB();
   
   HGLOBAL hCBDIB = NULL;
   if (hDIB)
   {
      DWORD dwSize = GlobalSize(hDIB);
      hCBDIB = GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE, dwSize);
      if (hCBDIB)
      {
         BYTE *pCBDIB = (BYTE *)GlobalLock(hCBDIB);
         memcpy(pCBDIB, (BYTE *)hDIB, dwSize);
         GlobalUnlock(hCBDIB);
      }
      
      GlobalFree(hDIB);
   }
   
   return hCBDIB;
}

...

if (OpenClipboard(AfxGetMainWnd()->m_hWnd))
{
   CISImage img; 

   ...put something in img...etc.

   HGLOBAL hDib = img.MakeClipboardDIB();
   
   HANDLE res = SetClipboardData(CF_DIB, hDib);
   ASSERT(res);

   CloseClipboard();
}

-c

------------------------------
Smaller Animals Software, Inc.
http://www.smalleranimals.com

Re: Bitmap and clipboard

#realJSOP4-Oct-01 7:57

#realJSOP

4-Oct-01 7:57

I can't find any reference to MakeDIB except for a MSDN sample app, and it requires parameters.

Re: Bitmap and clipboard

C^hris L^osinger4-Oct-01 7:59

C^hris L^osinger

4-Oct-01 7:59

yeah. that's my own function. it just creates a typical BITMAPINFOHEADER and image data DIB. i'm assuming you already have a DIB floating around somewhere.

-c

------------------------------
Smaller Animals Software, Inc.
http://www.smalleranimals.com

Re: Bitmap and clipboard

#realJSOP4-Oct-01 8:19

#realJSOP

4-Oct-01 8:19

Wel, I have a populated BITMAPINFOHEADER and a shitload of captured bytes... Smile | :)

I've been trying to make a DIB that can be stored to the clipboard. Trouble is, I don't know what I've done right, and what I've done wrong. Smile | :)

Why does something like this have to be so hard in a *graphical* operating system?

Re: Bitmap and clipboard

C^hris L^osinger4-Oct-01 8:23

C^hris L^osinger

4-Oct-01 8:23

sounds like you've got a DIB. have you tried displaying it (with something like StretchDIBits), just to be sure?

// Get source bitmap info
BITMAPINFO *pBMInfo = (LPBITMAPINFO)pDIB ;

// assumes a generic 24bit DIB
LPVOID lpDIBBits = (LPVOID)(pDIB + pBMInfo->bmiHeader.biSize);

// now blast it to the CDC passed in.
// lines returns the number of lines actually displayed
UINT32 lines = StretchDIBits(outHDC,
                     xPos, yPos,
                     outWidth, outHeight,
                     0,0,
                     inWidth,
                     inHeight,
                     lpDIBBits,
                     pBMInfo,
                     DIB_RGB_COLORS,
                     SRCCOPY);

that's the easiest way to tell if your DIB is correct/well-formed.

-c

------------------------------
Smaller Animals Software, Inc.
http://www.smalleranimals.com

Re: Bitmap and clipboard

#realJSOP4-Oct-01 8:42

#realJSOP

4-Oct-01 8:42

Yup, when I do a StrechDIBits, lines is equal to bmiHeader.biHeight.

Re: Bitmap and clipboard

C^hris L^osinger4-Oct-01 8:45

C^hris L^osinger

4-Oct-01 8:45

hmmm.. have you tried the clipboard code i posted above?

-c

------------------------------
Smaller Animals Software, Inc.
http://www.smalleranimals.com

Re: Bitmap and clipboard

#realJSOP4-Oct-01 8:49

#realJSOP

4-Oct-01 8:49

not yet - in the process tho...

Re: Bitmap and clipboard

Tomasz Sowinski4-Oct-01 7:10

Tomasz Sowinski

4-Oct-01 7:10

You can't just pass a dib handle to SetClipboardData - that would be too easy. You have to copy the contents into a global memory block and pass the handle of this memory block to SetClipboardData. DIBLOOK sample may be helpful; have a look at CopyHandle helper.

Tomasz Sowinski -- http://www.shooltz.com

Re: Bitmap and clipboard

#realJSOP4-Oct-01 7:16

#realJSOP

4-Oct-01 7:16

I've already tried the CopyHandle() method, and I get the same results.

Re: Bitmap and clipboard

Tomasz Sowinski4-Oct-01 7:17

Tomasz Sowinski

4-Oct-01 7:17

Can you blt the image to the screen?

Tomasz Sowinski -- http://www.shooltz.com

MCI CD Audio Mount and Eject?

Bryan Anslow4-Oct-01 6:10

Bryan Anslow

4-Oct-01 6:10

Hi,

I have an MCI application that reads/catalogs audio CD's using the CDDB Interface.

There are two things I would like to get it to do that it currently does not;
1) Recognise that a CD has been loaded into the drive, so that I do not need to have a menu item to add a new CD.
2) Eject the drive after the information has been cataloged.

I know that for 2) there are a couple of KB Articles, Q165721 and Q168180, but I would like a simpler, more universal method, if possible.

Many Thanks in advance for any info.

Bryan Anslow.

Re: MCI CD Audio Mount and Eject?

Tomasz Sowinski4-Oct-01 6:24

Tomasz Sowinski

4-Oct-01 6:24

Ejecting with MCI is easy. Assuming that you know the drive letter, send the following strings:

"open f: type cdaudio alias cdx0"
"set cdx0 door open"

cdx0 is just a sample alias. Any identifier should work.

Tomasz Sowinski -- http://www.shooltz.com

Re: MCI CD Audio Mount and Eject?

Bryan Anslow9-Oct-01 3:35

Bryan Anslow

9-Oct-01 3:35

Thanks Tomasz,

I use mciSendCommand() everywhere in this prog, so I found this worked;

mciSendCommand(_mciDevice, // Eject the CD
MCI_SET,
MCI_SET_DOOR_OPEN,
(DWORD)(LPVOID)&mciSet);

also, for finding out when a CD is inserted, I just added a line to my mainframe module (it's an MFC App)like;

ON_WM_DEVICECHANGE()

and the OnDeviceChange() function can find which device etc., by examining the passed parm,

Bryan.

Again: Are there any methods to construct a CFtpConnection object from a HINTERNET handle?

Chaos Lawful4-Oct-01 5:20

Chaos Lawful

4-Oct-01 5:20

I cannot find any useful functions from neither the MSDN nor the MFC source code. What can I do now? Please help me! Cry | :((

Law is meaningless without chaos.
Chaos without Law is equal to destruction.
Chaos and Law create our rich and colorful world.

Re: Again: Are there any methods to construct a CFtpConnection object from a HINTERNET handle?

NormDroid4-Oct-01 6:58

NormDroid

4-Oct-01 6:58

Have a look on this site PJ Naughter has written a class that does the job!

Norm Almond
Chief Technical Architect
FS Walker Hughes Limited

Re: Again: Are there any methods to construct a CFtpConnection object from a HINTERNET handle?

Chaos Lawful4-Oct-01 8:04

Chaos Lawful

4-Oct-01 8:04

I'm sorry to waste your time. But I don't know which article you refered to. Did you mean the FTPTransferDlg class? Confused | :confused:

Looking forward to your reply. Thank you.

Law is meaningless without chaos.
Chaos without Law is equal to destruction.
Chaos and Law create our rich and colorful world.

Deleting files in a program

Paresh Solanki4-Oct-01 4:39

Paresh Solanki

4-Oct-01 4:39

Can anyone tell me how to delete a file to the recycle bin programatically.

I can use CFile.Delete(), but this appears to delete the file completely, but what I would like to do is move the file into the recycle bin.

Thanks in advance for your help

Re: Deleting files in a program

Tomasz Sowinski4-Oct-01 4:44

Tomasz Sowinski

4-Oct-01 4:44

Use SHFileOperation with FO_DELETE flag.

Tomasz Sowinski -- http://www.shooltz.com

Re: Deleting files in a program

Tomasz Sowinski4-Oct-01 4:48

Tomasz Sowinski

4-Oct-01 4:48

One more thing: don't forget about FOF_ALLOWUNDO.

Tomasz Sowinski -- http://www.shooltz.com

Re: Deleting files in a program

Paresh Solanki4-Oct-01 5:42

Paresh Solanki

4-Oct-01 5:42

Thanks, That's just what I needed

How do I create a makefile from the command-line :confused:

Belarophon4-Oct-01 3:21

Belarophon

4-Oct-01 3:21

Hi @ all

I hope that somebody can tell me how I can create a makefile from the command-line (not from VC++ with project/export_makefile) from .dsp or .dsw files.

Thanks a lot

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