I want to print an image from a class library project without any gui.

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I have written following code. It is printing a blank document. I think there is something wrong with image loading or attachment with context

C++

LPTSTR    lpszDevice = TEXT("Datacard Printer");
    HDC hCardDC  = NULL;
    HDC localDC;
    HBITMAP hOld;

    BITMAP  bm;

    LPTSTR szFileName = "C://Front.bmp";
    HBITMAP phBitmap;  

   phBitmap = (HBITMAP)LoadImage( NULL, szFileName, IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE );

   if( phBitmap == NULL )
   {   
    DWORD error  = GetLastError();

    return -1;
   } 

    GetObject(phBitmap, sizeof(BITMAP), &bm );  
    hCardDC = CreateDC(NULL, lpszDevice, NULL, NULL);   
    localDC=CreateCompatibleDC(hCardDC);     

    hOld = (HBITMAP)::SelectObject(localDC,phBitmap);
    BOOL qRetBlit = ::BitBlt(hCardDC,0,0,924,624,localDC,0,0,SRCCOPY);

If i replace image loading code with textout("Test String") then it prints well.

Option 2
=========
I tried another option. Here Image is loaded in CBITMAP. but it is not attached to the
HDC.

C++

CImage frontImage;
frontImage.Load(_T("C:\\Front.bmp"));
CBitmap frontBitmap;
frontBitmap.Attach(frontImage.Detach());
HDC memHDC;
memHDC=CreateCompatibleDC(hCardDC);
HGDIOBJ pOldBitmap = SelectObject(memHDC, frontBitmap);
result = BitBlt(hCardDC, 0, 0, 994, 624, memHDC, 0, 0, SRCCOPY)

memHDC is always blank, shows unused. as image is not attached to context that is why printed doc remains blank.

Posted 23-Nov-14 19:25pm

Tanveer Asim

Updated 24-Nov-14 6:26am

v2

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Comments

KarstenK 24-Nov-14 2:46am

Does GetObject work fine? Can the output be in the "non-printable area"?

Try a black/white image.

Tanveer Asim 24-Nov-14 3:35am

GetObject has no effect, it do not fetch image. Also LoadImage is returning non null value but it is not valid value and GetLastError returns 0 but. Please view the attached image

Tanveer Asim 24-Nov-14 3:37am

sorry i think i cannot attach pictures here

Richard MacCutchan 24-Nov-14 5:02am

I don't think LPTSTR szFileName = "C://Front.bmp"; is a valid pathname. should be: LPTSTR szFileName = "C:\\Front.bmp";

Tanveer Asim 24-Nov-14 5:42am

i tried with all options like back/ forward slash, single double slash

Richard MacCutchan 24-Nov-14 5:48am

Why? There is only one form of string that is correct, and that is the one I showed you: "C:\\filename".

enhzflep 24-Nov-14 20:11pm

There is only one form of string that is correct, and that is the one I showed you: "C:\\filename"

Er, sorry old chap - but that's just patently and demonstrably false.

Each of the following are valid paths when passed to LoadImage.

"C:/filename.bmp"
"C://filename.bmp"
"C:\\filename.bmp"

Richard MacCutchan 25-Nov-14 3:24am

Quite right, ~~I don't know what I was thinking of yesterday.~~
I remember, trying those forms in a Command window. Duh!

enhzflep 25-Nov-14 6:43am

:)
I did wonder if it was a 'thinko', since it was a little too large for a typo.

Richard MacCutchan 25-Nov-14 7:07am

:)BTW I like your printing code.

enhzflep 25-Nov-14 7:30am

While I'd love to accept credit for it, I simply can't.

In fact, I'm able to thank AlwaysLearningNewStuff for much of it. I think to be honest, I only wrote the drawPage function. :red-face:

Tanveer Asim 24-Nov-14 11:42am

yes you are right but i tried other as well just to try

2 solutions

Solution 1

The LoadImage function returns a bitmap with colors mapped to those of the display device. This can't be used to be selected into a printer compatible device context because the color depth is usually not the same. Use the LR_CREATEDIBSECTION flag when loading the image to get a device independant bitmap.

You should also check if your printer supports raster operations by calling GetDeviceCaps and checking for the RASTERCAPS and RC_BITBLT flags. If the printer does not support raster operations, BitBlt will fail.

Posted 23-Nov-14 23:27pm

Jochen Arndt

Comments

Tanveer Asim 24-Nov-14 11:46am

I printed same image with GUI application. Image was displayed on form and then i printed using CDC. I am developing a class library project and don't want to display any GUI.

Jochen Arndt 24-Nov-14 11:59am

There you used GUI functions to prepare window content for printing. If you don't want to use GUI functions you must perform the preparation yourself. And one essential step is converting the image for the color depth of the printer. But using LoadImage like you do prepares the image for screen display (your call is similar to using LoadBitmap). From the LoadBitmap description in the MSDN:
"LoadBitmap creates a compatible bitmap of the display, which cannot be selected to a printer. To load a bitmap that you can select to a printer, call LoadImage and specify LR_CREATEDIBSECTION to create a DIB section. A DIB section can be selected to any device."

Tanveer Asim 24-Nov-14 12:14pm

thanks jochen for your help. I tried LoadImage with "LR_LOADFROMFILE | LR_CREATEDIBSECTION | LR_DEFAULTSIZE"but every time result is same. is there any other option other than LoadImage. I don't have good enough experience in vc++.

Jochen Arndt 24-Nov-14 12:22pm

Did you check all return values (CreateDC, SelectObject, BitBlt)?

Tanveer Asim 24-Nov-14 12:30pm

yes only CreateDC is successfully and creates dc, other two run without any error. IN select object nothing is assigned to dc and same is with BitBlt

Jochen Arndt 24-Nov-14 12:35pm

The GDI functions must not return NULL.
BitBlt must return TRUE (call GetLastError when FALSE is returned).

Tanveer Asim 25-Nov-14 5:20am

@Jochen BitBlt is returning 1 but i checked LoadImage retuns null HBITMAP.As you said as well actually the problem is with LoadImage, i am not sure what can be the alternative to this

Jochen Arndt 25-Nov-14 5:34am

But you are checking the return value in your code snippet. What is the value returned by GetLastError?
Also when this fails here it should also fail when loading the image to be shown by the GUI.

Tanveer Asim 25-Nov-14 5:46am

0 is returned by GetLastError, In GUI mode i used CDC and selecting bmp worked fine
CDC memDC;
memDC.CreateCompatibleDC(&dc);
CBitmap *pBmp = memDC.SelectObject(&bitmap);

Jochen Arndt 25-Nov-14 5:51am

You wrote "LoadImage retuns null".
At that point no DC is involved. So it should have also failed when selecting that NULL bitmap handle into any other DC.

Tanveer Asim 25-Nov-14 7:13am

yes you are right. But at that time i am using CBitmap that can be attached to CDC and HDC expects HBITMAP. Following code works fine

CImage frontImage;
frontImage.Load(_T("C:\\Front.bmp"));
CBITMAP bitmap;
bitmap.Attach(frontImage.Detach());
BITMAP bm;
bitmap.GetBitmap(&bm);
CDC memDC;
memDC.CreateCompatibleDC(&dc);
CBitmap *pBmp = memDC.SelectObject(&bitmap);
int w = bm.bmWidth;

Jochen Arndt 25-Nov-14 7:37am

I'm still on the first (initial) option because my answer is related to it. Bringing in different methods makes it really difficult to understand what we are talking about. I'm replying to your comment mentioning LoadImage and now you are talking about CImage::Load.

As already noted: The Cxxx classes are C++ classes that call internally the GDI functions. If you have a CBitmap for example, you can access the HBITMAP using the corresponding class operator. But the above code can't be used for printers because the objects are prepared for the screen. So the initial code (or those posted by enhzflep) is the better way.

So my question is now:
Which is the first call that fails when using the original code with LR_CREATEDIBSECTION and checking all return values?

There is one more option left:
You said that you were able to print from a GUI window. Why not use this method with a hidden window? That means: Use the GUI code but make the window you are using for drawing hidden.

Tanveer Asim 25-Nov-14 13:27pm

Jochen actually wrote this code to show that what is working in GUI mode.
LoadImage is the first call that fails it returned value is null and GetLastError returns 0.
About hidden window, can i use this solution in class library project. Because i am working on a dll that will be utilized by another component. if it works then i can go for any solution for initial release. Please suggest how i can do that

Jochen Arndt 25-Nov-14 13:48pm

LoadImage returns NULL and GetLastError too?
That is strange.

But some googling shows that others had this too:
- When there is a problem with the image file format (corrupted imnage)
- When out of GDI resources (DeleteObject not called for previously loaded bitmaps or other image objects not destroyed)

Tanveer Asim 25-Nov-14 13:54pm

yes GetLastError is not giving any error. I am not loading any other image before this call.
Is it possible that there is conflict due to multiple included header files? During testing multiple options i included many header files.

Jochen Arndt 25-Nov-14 14:00pm

No, it can't be a problem with header files.

I would check the image or try another one.

Tanveer Asim 25-Nov-14 14:35pm

I can open image in viewer, display on screen also print using cdc. i think the image is not currupt may be some other issue. I will try with some other images.

Tanveer Asim 27-Nov-14 1:32am

@Jochen i tried different images and one of them is loaded and if i open and save my image as 24 bit image then it is loaded in ImageLoad as well.i will try with rest of code now.

Tanveer Asim 1-Dec-14 3:06am

After i found that one image is loading then i opened my images in Paint and saved as 24bit Bitmap, now they are loading in LoadImage. And i am able to print using StretchBlt

Jochen Arndt 1-Dec-14 3:10am

Fine to hear that you have finally solved the problem.

Tanveer Asim 24-Nov-14 12:30pm

I have added another option to my question that i tried. Can you please have a look

Jochen Arndt 24-Nov-14 12:37pm

CImage and CBitmap are C++ classes that use the same GDI functions.

Tanveer Asim 24-Nov-14 13:11pm

and what about SelectObject(memHDC, frontBitmap). if there is image in fronBitmap then it should attach image to memHDC? currently it has no effect

Jochen Arndt 25-Nov-14 2:59am

Similar to the initial code: SelectObject will fail when the image is a DDB (Device Dependant Bitmap) for the screen and you are trying to select it into your printer DC.

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enhzflep · Accepted Answer · 2014-11-24T18:52:00

As mentioned, LoadImage loads an image ready for output on a screen. You have the alternative already given, or to use GDI+ to load the image. The advantage of using GDI+ is that not only is a DIB created, but you can also load formats including png, jpg and gif.

Provided you have already intialized GDI+, the following function will load an image ready for screen or print.

C++

// BMP, GIF, JPEG, PNG, TIFF, Exif, WMF, and EMF
HBITMAP mLoadImageFile(wchar_t *filename)
{
    HBITMAP result = NULL;
    Bitmap bitmap(filename, false);
    bitmap.GetHBITMAP(0, &result);
    return result;
}

Failing the use of GDI+, you can use the dib section flag with LoadImage.
The following code creates a 1 page pdf, loading a copy of the CP logo that's been converted from gif to bmp.

Just:
(a) change the name of the loaded image in the drawPage function
(b) change the name of the printer in the 1st line of main

Note: Link against the gdi32 and winspool libraries.

C++

#include <windows.h>
#include <commctrl.h>
#include <stdio.h>


void drawPage(HDC hdc)
{
    HBITMAP logo = (HBITMAP)LoadImage(NULL, "logo.bmp", IMAGE_BITMAP, 0,0, LR_LOADFROMFILE|LR_CREATEDIBSECTION);

    int pageWidth, pageHeight;
    pageWidth = GetDeviceCaps( hdc, HORZRES ),
    pageHeight = GetDeviceCaps( hdc, VERTRES );
    int dpiX, dpiY;

    dpiX = GetDeviceCaps(hdc, LOGPIXELSX);
    dpiY = GetDeviceCaps(hdc, LOGPIXELSY);

    double dpiMmX, dpiMmY;

    dpiMmX = dpiX / 25.4;
    dpiMmY = dpiY / 25.4;

    HBRUSH redBrush = CreateSolidBrush( RGB(255,0,0) );
    RECT pageRect = {0,0,pageWidth,pageHeight};

    int borderWidth = dpiMmX * 10;
    int borderHeight = dpiMmY * 10;

    RECT borderRect = {borderWidth, borderHeight, pageWidth-1-borderWidth, pageHeight-1-borderHeight};

    FrameRect(hdc, &pageRect, redBrush);
    int i;
    for (i=0; i<5; i++)
    {
        FrameRect(hdc, &borderRect, redBrush);
        InflateRect(&borderRect, -1, -1);
    }

    HDC memDC = CreateCompatibleDC(hdc);
    HBITMAP old = (HBITMAP)SelectObject(memDC, logo);
    StretchBlt(hdc, 100,100, 1000,540, memDC, 0,0, 250,125, SRCCOPY);
    SelectObject(memDC, old);
    DeleteObject(logo);
    DeleteDC(memDC);

    DeleteObject(redBrush);
}


void testPrint(char *szPrinterName)
{
    DOCINFO diDocInfo = {0};
    diDocInfo.cbSize = sizeof( DOCINFO );
    diDocInfo.lpszDocName = "printTest";

    HANDLE printerHandle;
    if (OpenPrinter(szPrinterName, &printerHandle, NULL) != 0)
    {
        HDC pDC2 = CreateDC("", szPrinterName, NULL, NULL);

        if( StartDoc( pDC2, &diDocInfo ) > 0 )
        {
            if( StartPage( pDC2 ) > 0 )
            {
                drawPage(pDC2);
                EndPage(pDC2);
            }
            EndDoc( pDC2 );
        }
        ClosePrinter(printerHandle);
    }
}

int main()
{
    testPrint("CutePDF Writer");
    return 0;
}

EDIT: MFC code added

C++

// CdcTest.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "CdcTest.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#endif


// The one and only application object

CWinApp theApp;

using namespace std;

void drawPage(HDC hdc)
{
    HBITMAP logo = (HBITMAP)LoadImage(NULL, L"c:/logo.bmp", IMAGE_BITMAP, 0,0, LR_LOADFROMFILE|LR_CREATEDIBSECTION);

    int pageWidth, pageHeight;
    pageWidth = GetDeviceCaps( hdc, HORZRES ),
    pageHeight = GetDeviceCaps( hdc, VERTRES );
    int dpiX, dpiY;

    dpiX = GetDeviceCaps(hdc, LOGPIXELSX);
    dpiY = GetDeviceCaps(hdc, LOGPIXELSY);

    double dpiMmX, dpiMmY;

    dpiMmX = dpiX / 25.4;
    dpiMmY = dpiY / 25.4;

    HBRUSH redBrush = CreateSolidBrush( RGB(255,0,0) );
    RECT pageRect = {0,0,pageWidth,pageHeight};

    int borderWidth = dpiMmX * 10;
    int borderHeight = dpiMmY * 10;

    RECT borderRect = {borderWidth, borderHeight, pageWidth-1-borderWidth, pageHeight-1-borderHeight};

    FrameRect(hdc, &pageRect, redBrush);
    int i;
    for (i=0; i<5; i++)
    {
        FrameRect(hdc, &borderRect, redBrush);
        InflateRect(&borderRect, -1, -1);
    }

    HDC memDC = CreateCompatibleDC(hdc);
    HBITMAP old = (HBITMAP)SelectObject(memDC, logo);
    StretchBlt(hdc, 100,100, 1000,540, memDC, 0,0, 250,125, SRCCOPY);
    SelectObject(memDC, old);
    DeleteObject(logo);
    DeleteDC(memDC);

    DeleteObject(redBrush);
}

int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
{
	int nRetCode = 0;

	HMODULE hModule = ::GetModuleHandle(NULL);

	if (hModule != NULL)
	{
		// initialize MFC and print and error on failure
		if (!AfxWinInit(hModule, NULL, ::GetCommandLine(), 0))
		{
			// TODO: change error code to suit your needs
			_tprintf(_T("Fatal Error: MFC initialization failed\n"));
			nRetCode = 1;
		}
		else
		{
			// TODO: code your application's behavior here.
			CDC memDC;
			memDC.CreateDCW(NULL, L"CutePDF Writer", NULL, NULL);

			DOCINFO diDocInfo = {0};
			diDocInfo.cbSize = sizeof( DOCINFO );
			diDocInfo.lpszDocName = L"printTest";

			if( StartDoc( memDC.GetSafeHdc(), &diDocInfo ) > 0 )
			{
				if( StartPage( memDC.GetSafeHdc() ) > 0 )
				{
					drawPage(memDC.GetSafeHdc());
					EndPage(memDC.GetSafeHdc());
				}
				EndDoc( memDC.GetSafeHdc() );
			}

		}
	}
	else
	{
		// TODO: change error code to suit your needs
		_tprintf(_T("Fatal Error: GetModuleHandle failed\n"));
		nRetCode = 1;
	}

	return nRetCode;
}