VFWImage.h.cpp

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// ************************************************************************
//      class CbmpUtils
//      Can capture bitmap from camera, display and save it.
//      Camera functionality provided by separate CVFWCapture class.
//  Author:     Audrey J. W. Mbogho
//      Email:  walegwa AT yahoo DOT com
//      Last Modified: January 2005
//      Previously, I tried to give credit here to all the
//      other people from whom I "borrowed" code. But that list
//      has grown to be too long for that. Apologies to all!
//      Environment: Visual C++, Windows 98, Logitech Webcam 4000 Pro.
// ************************************************************************

#include <fstream.h>
#include "VFWImage.h"
#include "VFWCapture.h"

// Constructor
// Initializes object data
CbmpUtils::CbmpUtils()
{
        Width = 0;
        Height = 0;             
        bmpData = '\0';         
        pbmi = NULL;    
        BitmapSize = 0;
}

CbmpUtils::~CbmpUtils()
{
}

// LoadBMP();
// Loads a DIB captured from video camera into a CbmpUtils object
int CbmpUtils::LoadBMP()
{
        BITMAPINFOHEADER bmih;  // Contained in BITMAPINFO structure

        CVFWCapture cap;
        cap.Initialize();       // Initialize first found VFW device

        pbmi = NULL;    // CaptureDIB will automatically allocate this if set to NULL

        // Capture an image from the capture device.
        if (cap.CaptureDIB(&pbmi, 0, &BitmapSize))
        {
                // Obtain args for SetDIBitsToDevice
                bmih = pbmi->bmiHeader;
                Width = bmih.biWidth;
                Height = bmih.biHeight;
                Height = (bmih.biHeight>0) ? bmih.biHeight : -bmih.biHeight; // absolute value
                bmpData = (char *)pbmi;

                bmpData += cap.CalcBitmapInfoSize(bmih);
        }
        cap.Destroy();  // Done using VFW object
        return 0;
}


// CbmpUtils::GDIPaint (hdc,x,y);
// Paints bitmap to a Windows DC
int CbmpUtils::GDIPaint (HDC hdc,int x=0,int y=0)
{
        int ret = 0;
        // Paint the image to the device.
        ret = SetDIBitsToDevice (hdc,x,y,Width,Height,0,0,
                0,Height,(LPVOID)bmpData,pbmi,0);
        return ret;
}


// SaveBMP()
// Saves current bitmap to file
int CbmpUtils::SaveBMP(LPCSTR fileName)
{
        BITMAPFILEHEADER bfh;

        if (!pbmi)
                return 1;                       // bitmap is empty

        ofstream bmpFile(fileName, ios::out | ios::binary);
        if (bmpFile.is_open())
        {
                bfh.bfType = 0x4d42;    // 0x42 = "B" 0x4d = "M"
                bfh.bfSize = (DWORD) BitmapSize + sizeof(BITMAPFILEHEADER);
                bfh.bfOffBits = (DWORD)   sizeof(BITMAPFILEHEADER) +
                                   sizeof(BITMAPINFOHEADER) +
                                    pbmi->bmiHeader.biClrUsed * 
                sizeof (RGBQUAD);
                bfh.bfReserved1 = 0;
                bfh.bfReserved2 = 0;

                bmpFile.write(reinterpret_cast<const char *>(&bfh),sizeof(bfh));
                bmpFile.write(reinterpret_cast<const char *>(pbmi),BitmapSize);
                bmpFile.close();
        }
        return 0;
}

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