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help remove errors in program

h4ever (529)
Can you help me remove these errors? I try to start to build program, one of my first tries, to capture content of window... I took this script which originally should capture screen and try to remake it.

h
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#pragma once
#include "targetver.h"
#include <stdio.h>
#include <tchar.h>


update
cpp: pls see the actual code and reports bellow
Last edited on
Peter87 (11178)
Looks like it doesn't know what CDC is on line 6 in capture.cpp. Is some #include missing maybe?
h4ever (529)
CDC Is unknown type. It is missing. I think. It should be type of Device Concept. Do I need to include some GDI library or this is standard?
Last edited on
h4ever (529)
EDIT

I had forgotten there must me main function. I removed the code for this one, looks better:

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// capture.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <conio.h>
#include <Windows.h>

using namespace std;

int main() {
HWND m_hWnd = FindWindow(NULL, _T("Map Viewer") ); 
cout << m_hWnd << " << " << endl;
getch();

// get the device context of the screen
HDC hScreenDC = CreateDC(_T("DISPLAY"), NULL, NULL, NULL);     

// and a device context to put it in
HDC hMemoryDC = CreateCompatibleDC(hScreenDC);

int x = GetDeviceCaps(hScreenDC, HORZRES);
int y = GetDeviceCaps(hScreenDC, VERTRES);

// maybe worth checking these are positive values
HBITMAP hBitmap = CreateCompatibleBitmap(hScreenDC, x, y);

// get a new bitmap
HBITMAP hOldBitmap = SelectObject(hMemoryDC, hBitmap);

BitBlt(hMemoryDC, 0, 0, width, height, hScreenDC, 0, 0, SRCCOPY);
hBitmap = SelectObject(hMemoryDC, hOldBitmap);

// clean up
DeleteDC(hMemoryDC);
DeleteDC(hScreenDC);
/*
HWND WINAPI FindWindow(
  _In_opt_  LPCTSTR lpClassName,
  _In_opt_  LPCTSTR lpWindowName
);
*/
}
Last edited on
h4ever (529)
EDIT
It still generates errors:

------ Rebuild All started: Project: capture2, Configuration: Debug Win32 ------
stdafx.cpp
capture.cpp
s:\temp\c++\algoritmy\capture2\capture\capture.cpp(13): warning C4996: 'getch': The POSIX name for this item is deprecated. Instead, use the ISO C++ conformant name: _getch. See online help for details.
p:\programy\programování\c++\visual studio 10.0\vc\include\conio.h(128) : see declaration of 'getch'
s:\temp\c++\algoritmy\capture2\capture\capture.cpp(28): error C2440: 'initializing' : cannot convert from 'HGDIOBJ' to 'HBITMAP'
Conversion from 'void*' to pointer to non-'void' requires an explicit cast
s:\temp\c++\algoritmy\capture2\capture\capture.cpp(30): error C2065: 'width' : undeclared identifier
s:\temp\c++\algoritmy\capture2\capture\capture.cpp(30): error C2065: 'height' : undeclared identifier
s:\temp\c++\algoritmy\capture2\capture\capture.cpp(31): error C2440: '=' : cannot convert from 'HGDIOBJ' to 'HBITMAP'
Conversion from 'void*' to pointer to non-'void' requires an explicit cast
Generating Code...
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
Last edited on
h4ever (529)
I did some changes so I can get hande of Window now, but the rest is mystic. Anybody can help?
h4ever (529)
I have finally found good script which after correction works. I remake it now to capture from window, but here I have a question. I try to use GdipCreateBitmapFromHBITMAP()

 
 
HBitmap = GdipCreateBitmapFromHBITMAP(HBitmap, 0, pBitmap);
but result is error:

error C3861: 'GdipCreateBitmapFromHBITMAP': identifier not found
I even try to include
#include <gdiplus.h> But still the same. How to fix?
Last edited on
h4ever (529)
I also get 'GdiPlus' : is not a class or namespace name
if I try to access the function through GdiPlus::, if I try define namespace, it occurs same error
h4ever (529)
Can you help to solve unresolved external problem in program using GDI+ Flat API?

stdafx.h:
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#pragma once
#include "targetver.h"
#include <stdio.h>
#include <tchar.h>
#include <windows.h>
#include <fstream>
#include <stdio.h>

#include <wingdi.h>
#include <gdiplus.h>
#include <ostream>


capture3/capture/capture.cpp
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/*Window capture example*/
#include "stdafx.h"
using namespace Gdiplus;
using namespace Gdiplus::DllExports;
// using namespace GdiPlus; 

#define SCREENWIDTH GetSystemMetrics(SM_CXSCREEN)
#define SCREENHEIGHT GetSystemMetrics(SM_CYSCREEN)

// HBITMAP g_hDeskBmp;
HDC g_hMemDC;
int g_nDCdata;

int main()
{
 // get desktop window handle (but can be handle of any window)
 HWND HCapture = FindWindow(NULL, _T("Map Viewer") );
//	HWND HCapture = GetDesktopWindow();
 if(!IsWindow(HCapture)) return 1;

/*
 BOOL PrintWindow(
  HWND hwnd, // A handle to the window that will be copied.
  HDC hdcBlt, // A handle to the device context.
  UINT nFlags // The drawing options: PW_CLIENTONLY
                        //     Only the client area of the window is copied to hdcBlt. By default, the entire window is copied.
);
*/

 // get window dimensions
 RECT rect;
 GetWindowRect(HCapture, &rect);

 size_t dx = rect.right - rect.left;
 size_t dy = rect.bottom - rect.top;

 // create BITMAPINFO structure
 // used by CreateDIBSection
 BITMAPINFO info;
 info.bmiHeader.biSize          = sizeof(BITMAPINFOHEADER);
 info.bmiHeader.biWidth         = dx;
 info.bmiHeader.biHeight        = dy;
 info.bmiHeader.biPlanes        = 1;
 info.bmiHeader.biBitCount      = 24;
 info.bmiHeader.biCompression   = BI_RGB;
 info.bmiHeader.biSizeImage     = 0;
 info.bmiHeader.biXPelsPerMeter = 0;
 info.bmiHeader.biYPelsPerMeter = 0;
 info.bmiHeader.biClrUsed       = 0;
 info.bmiHeader.biClrImportant  = 0;

 // a bitmap handle and a pointer its bit data
 HBITMAP HBitmap = 0;
 BYTE*   memory = 0;

 /** We should create Bitmap first and then Device Context,
     however when I want to create snapshot of window, I need to use
	 fnc PrintWindow to copy the visual window to Device Context.
	 So I need to create DC first. The DC will be compatible with
	 current screen.
 */
 
 // 1. FIRST we need to Create DC for PrintWindow function
 // HDC HDevice = GetDC(HCapture);
 HDC HDevice = CreateCompatibleDC(NULL);
 
 // 2. SECOND we need to CREATE BITMAP (Device Independent Bitmap)
 // bitmap = CreateDIBSection(HDevice, &info, DIB_RGB_COLORS, (void**)&memory, 0, 0);
 // THIS WAS WRONG DECLARATION: unsigned int * pBitmap;
 GpBitmap *pBitmap = NULL; // type Gdiplus::GpBitmap

  if (!PrintWindow(HCapture, HDevice, PW_CLIENTONLY)) return 2;
  
  SelectObject (HDevice, pBitmap); // hdc, hbm is GpBitmap is hgdiobj

  DllExports::GdipCreateBitmapFromHBITMAP(HBitmap, 0, &pBitmap);
 ReleaseDC(HCapture, HDevice);
 if(!HBitmap || !memory) return 1;

 // blit the contents of the desktop (winDC)
 // to the bitmap (selected in memDC)
 HDC winDC = GetWindowDC(HCapture);
 HDC memDC = CreateCompatibleDC(winDC);
 SelectObject(memDC, HBitmap);
 BitBlt(memDC, 0, 0, dx, dy, winDC, 0, 0, SRCCOPY);
 DeleteDC(memDC);
 ReleaseDC(HCapture, winDC);

 /** THIS IS WRONG! VARIABLE CANNOT POINT TO NOWHERE!*/
 // char *buffer; // First set the type and range and then make pointer:
  char *buffer = new char[50]; // RIGHT DECLARATION
 sprintf(buffer,"capture%d%d.bmp",dx,dy);
 // create bitmap file
 std::basic_ofstream <char> file(buffer, std::ios::binary);
 if(!file) { DeleteObject(HBitmap); return 1; }

 // initialize bitmap file headers
 BITMAPFILEHEADER fileHeader;
 BITMAPINFOHEADER infoHeader;

 fileHeader.bfType      = 0x4d42;
 fileHeader.bfSize      = 0;
 fileHeader.bfReserved1 = 0;
 fileHeader.bfReserved2 = 0;
 fileHeader.bfOffBits   = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);

 infoHeader.biSize          = sizeof(infoHeader);
 infoHeader.biWidth         = dx;
 infoHeader.biHeight        = dy;
 infoHeader.biPlanes        = 1;
 infoHeader.biBitCount      = 24;
 infoHeader.biCompression   = BI_RGB;
 infoHeader.biSizeImage     = 0;
 infoHeader.biXPelsPerMeter = 0;
 infoHeader.biYPelsPerMeter = 0;
 infoHeader.biClrUsed       = 0;
 infoHeader.biClrImportant  = 0;

 // save file headers
 file.write((char*)&fileHeader, sizeof(fileHeader));
 file.write((char*)&infoHeader, sizeof(infoHeader));

 // save 24-bit bitmap data
 int wbytes = (((24*dx + 31) & (~31))/8);
 int tbytes = (((24*dx + 31) & (~31))/8)*dy;
 file.write((char*)memory, tbytes);
 // delete bitmap
 DeleteObject(HBitmap);
 HBitmap = 0;
 memory = 0;
return 0;
}



Using Visual C++ Express 2010, getting this error:
------ Rebuild All started: Project: capture3, Configuration: Debug Win32 ------
stdafx.cpp
capture.cpp
\capture3\capture\capture.cpp(92): warning C4996: 'sprintf': This function or variable may be unsafe. Consider using sprintf_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
\visual studio 10.0\vc\include\stdio.h(371) : see declaration of 'sprintf'
Generating Code...
capture.obj : error LNK2019: unresolved external symbol _GdipCreateBitmapFromHBITMAP@12 referenced in function _main
\capture3\Debug\capture3.exe : fatal error LNK1120: 1 unresolved externals
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
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