📄 savescrjpg.cpp
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// SaveScrJpg.cpp: implementation of the SaveScrJpg class.
//
//////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include "SaveScrJpg.h"
#include "math.h"
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
HANDLE SaveScrJpg::DDBToDIB( HBITMAP hBitmap, DWORD dwCompression, HPALETTE hPal )
{
BITMAP bm;
BITMAPINFOHEADER bi;
LPBITMAPINFOHEADER lpbi;
DWORD dwLen;
HANDLE hDIB;
HANDLE handle;
HDC hDC;
ASSERT( hBitmap );
// The function has no arg for bitfields
if( dwCompression == BI_BITFIELDS )
return NULL;
// If a palette has not been supplied use defaul palette
if (hPal==NULL)
hPal = (HPALETTE) GetStockObject(DEFAULT_PALETTE);
// Get bitmap information
::GetObject(hBitmap,sizeof(bm),(LPSTR)&bm);
// Initialize the bitmapinfoheader
bi.biSize = sizeof(BITMAPINFOHEADER);
bi.biWidth = bm.bmWidth;
bi.biHeight = bm.bmHeight;
bi.biPlanes = 1;
bi.biBitCount = bm.bmPlanes * bm.bmBitsPixel;
bi.biCompression = dwCompression;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrUsed = 0;
bi.biClrImportant = 0;
// Compute the size of the infoheader and the color table
int nColors = (1 << bi.biBitCount);
if( nColors > 256 )
nColors = 0;
dwLen = bi.biSize + nColors * sizeof(RGBQUAD);
// We need a device context to get the DIB from
hDC = GetDC(NULL);
hPal = SelectPalette(hDC,hPal,FALSE);
RealizePalette(hDC);
// Allocate enough memory to hold bitmapinfoheader and color table
hDIB = GlobalAlloc(GMEM_FIXED,dwLen);
if (!hDIB){
SelectPalette(hDC,hPal,FALSE);
ReleaseDC(NULL,hDC);
return NULL;
}
lpbi = (LPBITMAPINFOHEADER)hDIB;
*lpbi = bi;
// Call GetDIBits with a NULL lpBits param, so the device driver
// will calculate the biSizeImage field
GetDIBits(hDC, hBitmap, 0L, (DWORD)bi.biHeight,
(LPBYTE)NULL, (LPBITMAPINFO)lpbi, (DWORD)DIB_RGB_COLORS);
bi = *lpbi;
// If the driver did not fill in the biSizeImage field, then compute it
// Each scan line of the image is aligned on a DWORD (32bit) boundary
if (bi.biSizeImage == 0){
bi.biSizeImage = ((((bi.biWidth * bi.biBitCount) + 31) & ~31) / 8)
* bi.biHeight;
// If a compression scheme is used the result may infact be larger
// Increase the size to account for this.
if (dwCompression != BI_RGB)
bi.biSizeImage = (bi.biSizeImage * 3) / 2;
}
// Realloc the buffer so that it can hold all the bits
dwLen += bi.biSizeImage;
if (handle = GlobalReAlloc(hDIB, dwLen, GMEM_MOVEABLE))
hDIB = handle;
else{
GlobalFree(hDIB);
// Reselect the original palette
SelectPalette(hDC,hPal,FALSE);
ReleaseDC(NULL,hDC);
return NULL;
}
// Get the bitmap bits
lpbi = (LPBITMAPINFOHEADER)hDIB;
// FINALLY get the DIB
BOOL bGotBits = GetDIBits( hDC, hBitmap,
0L, // Start scan line
(DWORD)bi.biHeight, // # of scan lines
(LPBYTE)lpbi // address for bitmap bits
+ (bi.biSize + nColors * sizeof(RGBQUAD)),
(LPBITMAPINFO)lpbi, // address of bitmapinfo
(DWORD)DIB_RGB_COLORS); // Use RGB for color table
if( !bGotBits )
{
GlobalFree(hDIB);
SelectPalette(hDC,hPal,FALSE);
ReleaseDC(NULL,hDC);
return NULL;
}
SelectPalette(hDC,hPal,FALSE);
ReleaseDC(NULL,hDC);
return hDIB;
}
//////////////////////////////////////////////////////////////////////
BOOL SaveScrJpg::JpegFromDib(HANDLE hDib, //Handle to DIB
int nQuality, //JPEG quality (0-100)
CString csJpeg, //Pathname to jpeg file
CString* pcsMsg) //Error msg to return
{
//Basic sanity checks...
if (nQuality < 0 || nQuality > 100 ||
hDib == NULL ||
pcsMsg == NULL ||
csJpeg == "")
{
if (pcsMsg != NULL)
*pcsMsg = "Invalid input data";
return FALSE;
}
*pcsMsg = "";
LPBITMAPINFOHEADER lpbi = (LPBITMAPINFOHEADER)hDib;
// BYTE *buf2 = 0;
//Use libjpeg functions to write scanlines to disk in JPEG format
struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr;
FILE* pOutFile; //Target file
int nSampsPerRow; //Physical row width in image buffer
JSAMPARRAY jsmpArray; //Pixel RGB buffer for JPEG file
cinfo.err = jpeg_std_error(&jerr); //Use default error handling (ugly!)
jpeg_create_compress(&cinfo);
if ((pOutFile = fopen(csJpeg, "wb")) == NULL)
{
*pcsMsg = "Cannot open ";
*pcsMsg += csJpeg;
jpeg_destroy_compress(&cinfo);
return FALSE;
}
jpeg_stdio_dest(&cinfo, pOutFile);
cinfo.image_width = lpbi->biWidth; //Image width and height, in pixels
cinfo.image_height = lpbi->biHeight;
cinfo.input_components = 3; //Color components per pixel
//(RGB_PIXELSIZE - see jmorecfg.h)
cinfo.in_color_space = JCS_RGB; //Colorspace of input image
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo,
nQuality, //Quality: 0-100 scale
TRUE); //Limit to baseline-JPEG values
jpeg_start_compress(&cinfo, TRUE);
//JSAMPLEs per row in output buffer
nSampsPerRow = cinfo.image_width * cinfo.input_components;
//Allocate array of pixel RGB values
jsmpArray = (*cinfo.mem->alloc_sarray)
((j_common_ptr) &cinfo,
JPOOL_IMAGE,
nSampsPerRow,
cinfo.image_height);
if (DibToSamps(hDib,
nSampsPerRow,
cinfo,
jsmpArray,
pcsMsg))
{
//Write the array of scan lines to the JPEG file
(void)jpeg_write_scanlines(&cinfo,
jsmpArray,
cinfo.image_height);
}
jpeg_finish_compress(&cinfo); //Always finish
rewind(pOutFile);/**/
fputc(0x00,pOutFile);
fputc(0x00,pOutFile);
fclose(pOutFile);
jpeg_destroy_compress(&cinfo); //Free resources
if (*pcsMsg != "")
return FALSE;
else
return TRUE;
}
//////////////////////////////////////////////////////////////////////
//This function fills a jsmpArray with the RGB values for the CBitmap.
//It has been improved to handle all legal bitmap formats.
//A jsmpArray is a big array of RGB values, 3 bytes per value.
//Note that rows of pixels are processed bottom to top:
//The data in the jsamp array must be arranged top to bottom.
//////////////////////////////////////////////////////////////////////
BOOL SaveScrJpg::DibToSamps(HANDLE hDib,
int nSampsPerRow,
struct jpeg_compress_struct cinfo,
JSAMPARRAY jsmpPixels,
CString* pcsMsg)
{
//Sanity...
if (hDib == NULL || nSampsPerRow <= 0 || pcsMsg == NULL)
{
if (pcsMsg !=NULL)
*pcsMsg="Invalid input data";
return FALSE;
}
int r=0, p=0, q=0, b=0, n=0,
nUnused=0, nBytesWide=0, nUsed=0, nLastBits=0, nLastNibs=0, nCTEntries=0,
nRow=0, nByte=0, nPixel=0;
BYTE bytCTEnt=0;
LPBITMAPINFOHEADER pbBmHdr= (LPBITMAPINFOHEADER)hDib; //The bit count tells you the format of the bitmap: //Decide how many entries will be in the color table (if any)
switch (pbBmHdr->biBitCount)
{
case 1:
nCTEntries = 2; //Monochrome
break;
case 4:
nCTEntries = 16; //16-color
break;
case 8:
nCTEntries = 256; //256-color
break;
case 16:
case 24:
case 32:
nCTEntries = 0; //No color table needed
break;
default:
*pcsMsg = "Invalid bitmap bit count";
return FALSE; //Unsupported format
}
//Point to the color table and pixels
DWORD dwCTab = (DWORD)pbBmHdr + pbBmHdr->biSize;
LPRGBQUAD pCTab = (LPRGBQUAD)(dwCTab);
LPSTR lpBits = (LPSTR)pbBmHdr +
(WORD)pbBmHdr->biSize +
(WORD)(nCTEntries * sizeof(RGBQUAD));
//Different formats for the image bits
LPBYTE lpPixels = (LPBYTE) lpBits;
RGBQUAD* pRgbQs = (RGBQUAD*)lpBits;
WORD* wPixels = (WORD*) lpBits;
//Set up the jsamps according to the bitmap's format.
//Note that rows are processed bottom to top, because
//that's how bitmaps are created.
switch (pbBmHdr->biBitCount)
{
case 1:
nUsed = (pbBmHdr->biWidth + 7) / 8;
nUnused = (((nUsed + 3) / 4) * 4) - nUsed;
nBytesWide = nUsed + nUnused;
nLastBits = 8 - ((nUsed * 8) - pbBmHdr->biWidth);
for (r=0; r < pbBmHdr->biHeight; r++)
{
for (p=0,q=0; p < nUsed; p++)
{
nRow=(pbBmHdr->biHeight-r-1) * nBytesWide;
nByte = nRow + p;
int nBUsed = (p <(nUsed - 1)) ? 8 : nLastBits;
for(b=0; b < nBUsed; b++)
{
bytCTEnt = lpPixels[nByte] << b;
bytCTEnt = bytCTEnt >> 7;
jsmpPixels[r][q+0] = pCTab[bytCTEnt].rgbRed;
jsmpPixels[r][q+1] = pCTab[bytCTEnt].rgbGreen;
jsmpPixels[r][q+2] = pCTab[bytCTEnt].rgbBlue;
q += 3;
}
}
}
break;
case 4:
nUsed = (pbBmHdr->biWidth + 1) / 2;
nUnused = (((nUsed + 3) / 4) * 4) - nUsed;
nBytesWide = nUsed + nUnused;
nLastNibs = 2 - ((nUsed * 2) - pbBmHdr->biWidth);
for (r=0; r < pbBmHdr->biHeight;r++)
{
for (p=0,q=0; p < nUsed;p++)
{
nRow=(pbBmHdr->biHeight-r-1) * nBytesWide;
nByte = nRow + p;
jsmpPixels[r][q+0] = pCTab[bytCTEnt].rgbRed;
jsmpPixels[r][q+1] = pCTab[bytCTEnt].rgbGreen;
jsmpPixels[r][q+2] = pCTab[bytCTEnt].rgbBlue;
q += 3;
}
}
break;
case 8: //Each byte is a pointer to a pixel color
nUnused = (((pbBmHdr->biWidth + 3) / 4) * 4) -
pbBmHdr->biWidth;
for (r=0;r < pbBmHdr->biHeight; r++)
{
for (p=0,q=0; p < pbBmHdr->biWidth; p++,q+=3)
{
nRow = (pbBmHdr->biHeight-r-1) * (pbBmHdr->biWidth + nUnused);
nPixel = nRow + p;
jsmpPixels[r][q+0] = pCTab[lpPixels[nPixel]].rgbRed;
jsmpPixels[r][q+1] = pCTab[lpPixels[nPixel]].rgbGreen;
jsmpPixels[r][q+2] = pCTab[lpPixels[nPixel]].rgbBlue;
}
}
break;
case 16: //Hi-color (16 bits per pixel)
for (r=0;r < pbBmHdr->biHeight; r++)
{
for (p=0,q=0; p < pbBmHdr->biWidth; p++,q+=3)
{
nRow = (pbBmHdr->biHeight-r-1) * pbBmHdr->biWidth;
nPixel = nRow + p;
RGBQUAD quad = QuadFromWord(wPixels[nPixel]);
jsmpPixels[r][q+0] = quad.rgbRed;
jsmpPixels[r][q+1] = quad.rgbGreen;
jsmpPixels[r][q+2] = quad.rgbBlue;
}
}
break;
case 24:
nBytesWide = (pbBmHdr->biWidth*3);
nUnused = (((nBytesWide + 3) / 4) * 4) -
nBytesWide;
nBytesWide += nUnused;
for (r=0;r<pbBmHdr->biHeight;r++)
{
for (p=0,q=0;p < (nBytesWide-nUnused); p+=3,q+=3)
{
nRow = (pbBmHdr->biHeight-r-1) * nBytesWide;
nPixel = nRow + p;
jsmpPixels[r][q+0] = lpPixels[nPixel+2]; //Red
jsmpPixels[r][q+1] = lpPixels[nPixel+1]; //Green
jsmpPixels[r][q+2] = lpPixels[nPixel+0]; //Blue
}
}
break;
case 32:
for (r=0; r < pbBmHdr->biHeight; r++)
{
for (p=0,q=0; p < pbBmHdr->biWidth; p++,q+=3)
{
nRow = (pbBmHdr->biHeight-r-1) *
pbBmHdr->biWidth;
nPixel = nRow + p;
jsmpPixels[r][q+0] = pRgbQs[nPixel].rgbRed;
jsmpPixels[r][q+1] = pRgbQs[nPixel].rgbGreen;
jsmpPixels[r][q+2] = pRgbQs[nPixel].rgbBlue;
}
}
break;
} //end switch
return TRUE;
}
//////////////////////////////////////////////////////////////////////
//This function turns a 16-bit pixel
//into an RGBQUAD value.
//////////////////////////////////////////////////////////////////////
RGBQUAD SaveScrJpg::QuadFromWord(WORD b16)
{
BYTE bytVals[] =
{
0, 16, 24, 32, 40, 48, 56, 64,
72, 80, 88, 96, 104,112,120,128,
136,144,152,160,168,176,184,192,
200,208,216,224,232,240,248,255
};
WORD wR = b16;
WORD wG = b16;
WORD wB = b16;
wR <<= 1; wR >>= 11;
wG <<= 6; wG >>= 11;
wB <<= 11; wB >>= 11;
RGBQUAD rgb;
rgb.rgbReserved = 0;
rgb.rgbBlue = bytVals[wB];
rgb.rgbGreen = bytVals[wG];
rgb.rgbRed = bytVals[wR];
return rgb;
}
//////////////////////////////////////////////////////////////////////
SaveScrJpg::SaveScrJpg()
{
strcpy(SaveAddr,"C:" );
}
//////////////////////////////////////////////////////////////////////
SaveScrJpg::~SaveScrJpg()
{
}
//////////////////////////////////////////////////////////////////////
void SaveScrJpg::SaveScreen(int jpgOrder)
{
HDC hScrDC, hMemDC;
HBITMAP hBitmap, hOldBitmap;
int nX, nY, nX2, nY2;
int nWidth, nHeight;
int xScrn, yScrn;
CString one;
hScrDC = CreateDC("DISPLAY", NULL, NULL, NULL);
hMemDC = CreateCompatibleDC(hScrDC);
nX = 0;
nY = 0;
nX2 =GetDeviceCaps(hScrDC, HORZRES);
nY2 =GetDeviceCaps(hScrDC, VERTRES);
/// get screen resolution
xScrn =GetDeviceCaps(hScrDC, HORZRES);
yScrn =GetDeviceCaps(hScrDC, VERTRES);
//make sure bitmap rectangle is visible
if (nX < 0)
nX = 0;
if (nY < 0)
nY = 0;
if (nX2 > xScrn)
nX2 = xScrn;
if (nY2 > yScrn)
nY2 = yScrn;
nWidth = nX2 - nX;
nHeight = nY2 - nY;
// create a bitmap compatible with the screen DC
hBitmap = CreateCompatibleBitmap(hScrDC, nWidth, nHeight);
hOldBitmap =(HBITMAP) SelectObject(hMemDC, hBitmap);
BitBlt(hMemDC, 0, 0, nWidth, nHeight, hScrDC, nX, nY, SRCCOPY);
HANDLE hDib=DDBToDIB( hBitmap, BI_RGB, NULL);
CString csMsg = "";
CString RealSaveName;
RealSaveName.Format("%s\\%d.jpg",SaveAddr,jpgOrder);
if (hDib != NULL)
{
if (!JpegFromDib(hDib,
45, //画面质量 0-100
RealSaveName,&csMsg))
::MessageBox(NULL,csMsg,NULL,MB_OK);
else
::GlobalFree(hDib);
}
else
::MessageBox(NULL,"Failed to load IDB_TEST",NULL,MB_OK);
::SelectObject(hMemDC,hOldBitmap);
::DeleteObject(hBitmap);
::DeleteDC(hScrDC);
::DeleteDC(hMemDC);
}
//////////////////////////////////////////////////////////////////////
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