/*
* File: ximaj2k.cpp
* Purpose: Platform Independent J2K Image Class Loader and Writer
* 12/Jul/2002 Davide Pizzolato - www.xdp.it
* CxImage version 5.99c 17/Oct/2004
*/
#include "ximaj2k.h"
#if CXIMAGE_SUPPORT_J2K
#define CEILDIV(a,b) ((a+b-1)/b)
////////////////////////////////////////////////////////////////////////////////
bool CxImageJ2K::Decode(CxFile *hFile)
{
if (hFile == NULL) return false;
try
{
BYTE* src;
long len;
j2k_image_t *img=NULL;
j2k_cp_t *cp=NULL;
long i,x,y,w,h,max;
len=hFile->Size();
src=(BYTE*)malloc(len);
hFile->Read(src, len, 1);
if (!j2k_decode(src, len, &img, &cp)) {
free(src);
throw "failed to decode J2K image!";
}
free(src);
if (img->numcomps==3 &&
img->comps[0].dx==img->comps[1].dx &&
img->comps[1].dx==img->comps[2].dx &&
img->comps[0].dy==img->comps[1].dy &&
img->comps[1].dy==img->comps[2].dy &&
img->comps[0].prec==img->comps[1].prec &&
img->comps[1].prec==img->comps[2].prec)
{
w=CEILDIV(img->x1-img->x0, img->comps[0].dx);
h=CEILDIV(img->y1-img->y0, img->comps[0].dy);
max=(1<<img->comps[0].prec)-1;
Create(w,h,24,CXIMAGE_FORMAT_J2K);
RGBQUAD c;
for (i=0,y=0; y<h; y++) {
for (x=0; x<w; x++,i++){
c.rgbRed = img->comps[0].data[i];
c.rgbGreen = img->comps[1].data[i];
c.rgbBlue = img->comps[2].data[i];
SetPixelColor(x,h-1-y,c);
}
}
} else {
int compno;
info.nNumFrames = img->numcomps;
if ((info.nFrame<0)||(info.nFrame>=info.nNumFrames)){
j2k_destroy(&img,&cp);
throw "wrong frame!";
}
for (compno=0; compno<=info.nFrame; compno++) {
w=CEILDIV(img->x1-img->x0, img->comps[compno].dx);
h=CEILDIV(img->y1-img->y0, img->comps[compno].dy);
max=(1<<img->comps[compno].prec)-1;
Create(w,h,8,CXIMAGE_FORMAT_J2K);
SetGrayPalette();
for (i=0,y=0; y<h; y++) {
for (x=0; x<w; x++,i++){
SetPixelIndex(x,h-1-y,img->comps[compno].data[i]);
}
}
}
}
j2k_destroy(&img,&cp);
} catch (char *message) {
strncpy(info.szLastError,message,255);
return FALSE;
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
bool CxImageJ2K::Encode(CxFile * hFile)
{
if (EncodeSafeCheck(hFile)) return false;
if (head.biClrUsed!=0 && !IsGrayScale()){
strcpy(info.szLastError,"J2K can save only RGB or GrayScale images");
return false;
}
int i,x,y;
j2k_image_t *img;
j2k_cp_t *cp;
j2k_tcp_t *tcp;
j2k_tccp_t *tccp;
img = (j2k_image_t *)calloc(sizeof(j2k_image_t),1);
cp = (j2k_cp_t *)calloc(sizeof(j2k_cp_t),1);
cp->tx0=0; cp->ty0=0;
cp->tw=1; cp->th=1;
cp->tcps=(j2k_tcp_t*)calloc(sizeof(j2k_tcp_t),1);
tcp=&cp->tcps[0];
long w=head.biWidth;
long h=head.biHeight;
tcp->numlayers=1;
for (i=0;i<tcp->numlayers;i++) tcp->rates[i]=(w*h*GetJpegQuality())/600;
if (IsGrayScale()) {
img->x0=0;
img->y0=0;
img->x1=w;
img->y1=h;
img->numcomps=1;
img->comps=(j2k_comp_t*)calloc(sizeof(j2k_comp_t),1);
img->comps[0].data=(int*)calloc(w*h*sizeof(int),1);
img->comps[0].prec=8;
img->comps[0].sgnd=0;
img->comps[0].dx=1;
img->comps[0].dy=1;
for (i=0,y=0; y<h; y++) {
for (x=0; x<w; x++,i++){
img->comps[0].data[i]=GetPixelIndex(x,h-1-y);
}
}
} else if (!IsIndexed()) {
img->x0=0;
img->y0=0;
img->x1=w;
img->y1=h;
img->numcomps=3;
img->comps=(j2k_comp_t*)calloc(img->numcomps*sizeof(j2k_comp_t),1);
for (i=0; i<img->numcomps; i++) {
img->comps[i].data=(int*)calloc(w*h*sizeof(int),1);
img->comps[i].prec=8;
img->comps[i].sgnd=0;
img->comps[i].dx=1;
img->comps[i].dy=1;
}
RGBQUAD c;
for (i=0,y=0; y<h; y++) {
for (x=0; x<w; x++,i++){
c=GetPixelColor(x,h-1-y);
img->comps[0].data[i]=c.rgbRed;
img->comps[1].data[i]=c.rgbGreen;
img->comps[2].data[i]=c.rgbBlue;
}
}
} else {
return 0;
}
cp->tdx=img->x1-img->x0;
cp->tdy=img->y1-img->y0;
tcp->csty=0;
tcp->prg=0;
tcp->mct=img->numcomps==3?1:0;
tcp->tccps=(j2k_tccp_t*)calloc(img->numcomps*sizeof(j2k_tccp_t),1);
int ir=0; /* or 1 ???*/
for (i=0; i<img->numcomps; i++) {
tccp=&tcp->tccps[i];
tccp->csty=0;
tccp->numresolutions=6;
tccp->cblkw=6;
tccp->cblkh=6;
tccp->cblksty=0;
tccp->qmfbid=ir?0:1;
tccp->qntsty=ir?J2K_CCP_QNTSTY_SEQNT:J2K_CCP_QNTSTY_NOQNT;
tccp->numgbits=2;
tccp->roishift=0;
j2k_calc_explicit_stepsizes(tccp, img->comps[i].prec);
}
BYTE* dest=(BYTE*)calloc(tcp->rates[tcp->numlayers-1]+2,1);
long len = j2k_encode(img, cp, dest, tcp->rates[tcp->numlayers-1]+2);
if (len==0) {
strcpy(info.szLastError,"J2K failed to encode image");
} else {
hFile->Write(dest, len, 1);
}
free(dest);
j2k_destroy(&img,&cp);
return (len!=0);
}
////////////////////////////////////////////////////////////////////////////////
static const double dwt_norms_97[4][10]={
{1.000, 1.965, 4.177, 8.403, 16.90, 33.84, 67.69, 135.3, 270.6, 540.9},
{2.022, 3.989, 8.355, 17.04, 34.27, 68.63, 137.3, 274.6, 549.0},
{2.022, 3.989, 8.355, 17.04, 34.27, 68.63, 137.3, 274.6, 549.0},
{2.080, 3.865, 8.307, 17.18, 34.71, 69.59, 139.3, 278.6, 557.2}
};
////////////////////////////////////////////////////////////////////////////////
void CxImageJ2K::j2k_calc_explicit_stepsizes(j2k_tccp_t *tccp, int prec) {
int numbands, bandno;
numbands=3*tccp->numresolutions-2;
for (bandno=0; bandno<numbands; bandno++) {
double stepsize;
int resno, level, orient, gain;
resno=bandno==0?0:(bandno-1)/3+1;
orient=bandno==0?0:(bandno-1)%3+1;
level=tccp->numresolutions-1-resno;
gain=tccp->qmfbid==0?0:(orient==0?0:(orient==1||orient==2?1:2));
if (tccp->qntsty==J2K_CCP_QNTSTY_NOQNT) {
stepsize=1.0;
} else {
double norm=dwt_norms_97[orient][level];
stepsize=(1<<(gain+1))/norm;
}
j2k_encode_stepsize((int)floor(stepsize*8192.0), prec+gain, &tccp->stepsizes[bandno].expn, &tccp->stepsizes[bandno].mant);
}
}
////////////////////////////////////////////////////////////////////////////////
void CxImageJ2K::j2k_encode_stepsize(int stepsize, int numbps, int *expn, int *mant) {
int p, n;
p=j2k_floorlog2(stepsize)-13;
n=11-j2k_floorlog2(stepsize);
*mant=(n<0?stepsize>>-n:stepsize<<n)&0x7ff;
*expn=numbps-p;
}
////////////////////////////////////////////////////////////////////////////////
int CxImageJ2K::j2k_floorlog2(int a) {
int l;
for (l=0; a>1; l++) {
a>>=1;
}
return l;
}
////////////////////////////////////////////////////////////////////////////////
#endif // CXIMAGE_SUPPORT_J2K
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