www.pudn.com > CXIMAGE_SRC.ZIP > ximajbg.cpp

/* 
 * File:	ximajbg.cpp 
 * Purpose:	Platform Independent JBG Image Class Loader and Writer 
 * 18/Aug/2002  
 * CxImage version 5.00 23/Aug/2002 
 */ 
 
#include "ximajbg.h" 
 
#if CXIMAGE_SUPPORT_JBG 
 
#include "ximaiter.h" 
 
#define JBIG_BUFSIZE 8192 
 
//////////////////////////////////////////////////////////////////////////////// 
bool CxImageJBG::Decode(CxFile *hFile) 
{ 
	if (hFile == NULL) return false; 
 
	struct jbg_dec_state jbig_state; 
	unsigned long xmax = 4294967295UL, ymax = 4294967295UL; 
	unsigned int len, cnt; 
	BYTE *buffer,*p; 
	int result; 
 
  try 
  { 
	jbg_dec_init(&jbig_state); 
	jbg_dec_maxsize(&jbig_state, xmax, ymax); 
 
	buffer = (BYTE*)malloc(JBIG_BUFSIZE); 
	if (!buffer) throw "Sorry, not enough memory available!"; 
 
	result = JBG_EAGAIN; 
	do { 
		len = hFile->Read(buffer, 1, JBIG_BUFSIZE); 
		if (!len) break; 
		cnt = 0; 
		p = buffer; 
		while (len > 0 && (result == JBG_EAGAIN || result == JBG_EOK)) { 
			result = jbg_dec_in(&jbig_state, p, len, &cnt); 
			p += cnt; 
			len -= cnt; 
		} 
	} while (result == JBG_EAGAIN || result == JBG_EOK); 
 
	if (hFile->Error()) 
		throw "Problem while reading input file"; 
	if (result != JBG_EOK && result != JBG_EOK_INTR) 
		throw "Problem with input file";  
 
	int w, h, bpp, planes, ew; 
 
	w = jbg_dec_getwidth(&jbig_state); 
	h = jbg_dec_getheight(&jbig_state); 
	planes = jbg_dec_getplanes(&jbig_state); 
	bpp = (planes+7)>>3; 
	ew = (w + 7)>>3; 
 
	switch (planes){ 
	case 1: 
		{ 
			BYTE* binary_image = jbg_dec_getimage(&jbig_state, 0); 
 
			if (!Create(w,h,1,CXIMAGE_FORMAT_JBG)) 
				throw "Can't allocate memory"; 
 
			SetPaletteIndex(0,255,255,255); 
			SetPaletteIndex(1,0,0,0); 
 
			CImageIterator iter(this); 
			iter.Upset(); 
			for (int i=0;i>3; 
	ew = (w + 7)>>3; 
 
	BYTE mask; 
	RGBQUAD *rgb = GetPalette(); 
	if (CompareColors(&rgb[0],&rgb[1])<0) mask=255; else mask=0; 
 
	BYTE *buffer = (BYTE*)malloc(ew*h*2); 
	if (!buffer) { 
		strcpy(info.szLastError,"Sorry, not enough memory available!"); 
		return false; 
	} 
 
	for (y=0; yError()){ 
		strcpy(info.szLastError,"Problem while writing JBG file"); 
		return false; 
	} 
 
	return true; 
} 
//////////////////////////////////////////////////////////////////////////////// 
#endif 	// CXIMAGE_SUPPORT_JBG