📄 jpegfile.cpp
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if (inBuf==NULL)
return NULL;
BYTE *tmp;
tmp=(BYTE *)new BYTE[height * widthPix * 3];
if (tmp==NULL)
return NULL;
UINT row;
for (row=0;row<height;row++) {
memcpy((tmp+row * widthPix * 3),
(inBuf + row * widthBytes),
widthPix * 3);
}
return tmp;
}
//
//
//
BOOL JpegFile::RGBToJpegFile(TCHAR *fileName,
BYTE *dataBuf,
UINT widthPix,
UINT height,
BOOL color,
int quality)
{
if (dataBuf==NULL)
return FALSE;
if (widthPix==0)
return FALSE;
if (height==0)
return FALSE;
LPBYTE tmp;
if (!color) {
tmp = (BYTE*)new BYTE[widthPix*height];
if (tmp==NULL) {
OutputDebugStringW(TEXT("JPEG :Memory error.\r\n"));
return FALSE;
}
UINT row,col;
for (row=0;row<height;row++) {
for (col=0;col<widthPix;col++) {
LPBYTE pRed, pGrn, pBlu;
pRed = dataBuf + row * widthPix * 3 + col * 3;
pGrn = dataBuf + row * widthPix * 3 + col * 3 + 1;
pBlu = dataBuf + row * widthPix * 3 + col * 3 + 2;
// luminance
int lum = (int)(.299 * (double)(*pRed) + .587 * (double)(*pGrn) + .114 * (double)(*pBlu));
LPBYTE pGray;
pGray = tmp + row * widthPix + col;
*pGray = (BYTE)lum;
}
}
}
struct jpeg_compress_struct cinfo;
/* More stuff */
FILE * outfile=NULL; /* target file */
int row_stride; /* physical row widthPix in image buffer */
struct my_error_mgr jerr;
/* Step 1: allocate and initialize JPEG compression object */
cinfo.err = jpeg_std_error(&jerr.pub);
jerr.pub.error_exit = my_error_exit;
/* Establish the setjmp return context for my_error_exit to use. */
if (setjmp(jerr.setjmp_buffer)) {
/* If we get here, the JPEG code has signaled an error.
* We need to clean up the JPEG object, close the input file, and return.
*/
jpeg_destroy_compress(&cinfo);
if (outfile!=NULL)
fclose(outfile);
if (!color) {
delete [] tmp;
}
return FALSE;
}
/* Now we can initialize the JPEG compression object. */
jpeg_create_compress(&cinfo);
/* Step 2: specify data destination (eg, a file) */
/* Note: steps 2 and 3 can be done in either order. */
if ((outfile = _tfopen(fileName, TEXT("wb"))) == NULL) {
OutputDebugStringW(TEXT("JPEG :Can't open file.\r\n"));
return FALSE;
}
jpeg_stdio_dest(&cinfo, outfile);
/* Step 3: set parameters for compression */
/* First we supply a description of the input image.
* Four fields of the cinfo struct must be filled in:
*/
cinfo.image_width = widthPix; /* image widthPix and height, in pixels */
cinfo.image_height = height;
if (color) {
cinfo.input_components = 3; /* # of color components per pixel */
cinfo.in_color_space = JCS_RGB; /* colorspace of input image */
} else {
cinfo.input_components = 1; /* # of color components per pixel */
cinfo.in_color_space = JCS_GRAYSCALE; /* colorspace of input image */
}
/* Now use the library's routine to set default compression parameters.
* (You must set at least cinfo.in_color_space before calling this,
* since the defaults depend on the source color space.)
*/
jpeg_set_defaults(&cinfo);
/* Now you can set any non-default parameters you wish to.
* Here we just illustrate the use of quality (quantization table) scaling:
*/
jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */);
/* Step 4: Start compressor */
/* TRUE ensures that we will write a complete interchange-JPEG file.
* Pass TRUE unless you are very sure of what you're doing.
*/
jpeg_start_compress(&cinfo, TRUE);
/* Step 5: while (scan lines remain to be written) */
/* jpeg_write_scanlines(...); */
/* Here we use the library's state variable cinfo.next_scanline as the
* loop counter, so that we don't have to keep track ourselves.
* To keep things simple, we pass one scanline per call; you can pass
* more if you wish, though.
*/
row_stride = widthPix * 3; /* JSAMPLEs per row in image_buffer */
while (cinfo.next_scanline < cinfo.image_height) {
/* jpeg_write_scanlines expects an array of pointers to scanlines.
* Here the array is only one element long, but you could pass
* more than one scanline at a time if that's more convenient.
*/
LPBYTE outRow;
if (color) {
outRow = dataBuf + (cinfo.next_scanline * widthPix * 3);
} else {
outRow = tmp + (cinfo.next_scanline * widthPix);
}
(void) jpeg_write_scanlines(&cinfo, &outRow, 1);
}
/* Step 6: Finish compression */
jpeg_finish_compress(&cinfo);
/* After finish_compress, we can close the output file. */
fclose(outfile);
/* Step 7: release JPEG compression object */
/* This is an important step since it will release a good deal of memory. */
jpeg_destroy_compress(&cinfo);
if (!color)
delete [] tmp;
/* And we're done! */
return TRUE;
}
//
// stash a scanline
//
void j_putRGBScanline(BYTE *jpegline,
int widthPix,
BYTE *outBuf,
int row)
{
int offset = row * widthPix * 3;
int count;
for (count=0;count<widthPix;count++)
{
*(outBuf + offset + count * 3 + 0) = *(jpegline + count * 3 + 0);
*(outBuf + offset + count * 3 + 1) = *(jpegline + count * 3 + 1);
*(outBuf + offset + count * 3 + 2) = *(jpegline + count * 3 + 2);
}
}
//
// stash a gray scanline
//
void j_putGrayScanlineToRGB(BYTE *jpegline,
int widthPix,
BYTE *outBuf,
int row)
{
int offset = row * widthPix * 3;
int count;
for (count=0;count<widthPix;count++) {
BYTE iGray;
// get our grayscale value
iGray = *(jpegline + count);
*(outBuf + offset + count * 3 + 0) = iGray;
*(outBuf + offset + count * 3 + 1) = iGray;
*(outBuf + offset + count * 3 + 2) = iGray;
}
}
//
// copies BYTE buffer into DWORD-aligned BYTE buffer
// return addr of new buffer
//
BYTE * JpegFile::MakeDwordAlignedBuf(BYTE *dataBuf,
UINT widthPix, // pixels!!
UINT height,
UINT *uiOutWidthBytes) // bytes!!!
{
////////////////////////////////////////////////////////////
// what's going on here? this certainly means trouble
if (dataBuf==NULL)
return NULL;
////////////////////////////////////////////////////////////
// how big is the smallest DWORD-aligned buffer that we can use?
UINT uiWidthBytes;
uiWidthBytes = WIDTHBYTES(widthPix * 24);
DWORD dwNewsize=(DWORD)((DWORD)uiWidthBytes *
(DWORD)height);
BYTE *pNew;
////////////////////////////////////////////////////////////
// alloc and open our new buffer
pNew=(BYTE *)new BYTE[dwNewsize];
if (pNew==NULL) {
return NULL;
}
////////////////////////////////////////////////////////////
// copy row-by-row
UINT uiInWidthBytes = widthPix * 3;
UINT uiCount;
for (uiCount=0;uiCount < height;uiCount++) {
BYTE * bpInAdd;
BYTE * bpOutAdd;
ULONG lInOff;
ULONG lOutOff;
lInOff=uiInWidthBytes * uiCount;
lOutOff=uiWidthBytes * uiCount;
bpInAdd= dataBuf + lInOff;
bpOutAdd= pNew + lOutOff;
memcpy(bpOutAdd,bpInAdd,uiInWidthBytes);
}
*uiOutWidthBytes=uiWidthBytes;
return pNew;
}
//
// vertically flip a buffer
// note, this operates on a buffer of widthBytes bytes, not pixels!!!
//
BOOL JpegFile::VertFlipBuf(BYTE * inbuf,
UINT widthBytes,
UINT height)
{
BYTE *tb1;
BYTE *tb2;
if (inbuf==NULL)
return FALSE;
UINT bufsize;
bufsize=widthBytes;
tb1= (BYTE *)new BYTE[bufsize];
if (tb1==NULL) {
return FALSE;
}
tb2= (BYTE *)new BYTE [bufsize];
if (tb2==NULL) {
delete [] tb1;
return FALSE;
}
UINT row_cnt;
ULONG off1=0;
ULONG off2=0;
for (row_cnt=0;row_cnt<(height+1)/2;row_cnt++) {
off1=row_cnt*bufsize;
off2=((height-1)-row_cnt)*bufsize;
memcpy(tb1,inbuf+off1,bufsize);
memcpy(tb2,inbuf+off2,bufsize);
memcpy(inbuf+off1,tb2,bufsize);
memcpy(inbuf+off2,tb1,bufsize);
}
delete [] tb1;
delete [] tb2;
return TRUE;
}
//
// swap Rs and Bs
//
// Note! this does its stuff on buffers with a whole number of pixels
// per data row!!
//
BOOL JpegFile::BGRFromRGB(BYTE *buf, UINT widthPix, UINT height)
{
if (buf==NULL)
return FALSE;
UINT col, row;
for (row=0;row<height;row++) {
for (col=0;col<widthPix;col++) {
LPBYTE pRed, pGrn, pBlu;
pRed = buf + row * widthPix * 3 + col * 3;
pGrn = buf + row * widthPix * 3 + col * 3 + 1;
pBlu = buf + row * widthPix * 3 + col * 3 + 2;
// swap red and blue
BYTE tmp;
tmp = *pRed;
*pRed = *pBlu;
*pBlu = tmp;
}
}
return TRUE;
}
//
// Note! this does its stuff on buffers with a whole number of pixels
// per data row!!
//
BOOL JpegFile::MakeGrayScale(BYTE *buf, UINT widthPix, UINT height)
{
if (buf==NULL)
return FALSE;
UINT row,col;
for (row=0;row<height;row++) {
for (col=0;col<widthPix;col++) {
LPBYTE pRed, pGrn, pBlu;
pRed = buf + row * widthPix * 3 + col * 3;
pGrn = buf + row * widthPix * 3 + col * 3 + 1;
pBlu = buf + row * widthPix * 3 + col * 3 + 2;
// luminance
int lum = (int)(.299 * (double)(*pRed) + .587 * (double)(*pGrn) + .114 * (double)(*pBlu));
*pRed = (BYTE)lum;
*pGrn = (BYTE)lum;
*pBlu = (BYTE)lum;
}
}
return TRUE;
}
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