/**
* HistogramStretch
* \param method: 0 = luminance (default), 1 = linked channels , 2 = independent channels.
* \param threshold: minimum percentage level in the histogram to recognize it as meaningful. Range: 0.0 to 1.0; default = 0; typical = 0.005 (0.5%);
* \return true if everything is ok
* \author [dave] and [nipper]; changes [DP]
*/
bool CxImage::HistogramStretch(long method, double threshold)
{
if (!pDib) return false;
double dbScaler = 50.0/head.biHeight;
long x,y;
if ((head.biBitCount==8) && IsGrayScale()){
double p[256];
memset(p, 0, 256*sizeof(double));
for (y=0; y<head.biHeight; y++)
{
info.nProgress = (long)(y*dbScaler);
if (info.nEscape) break;
for (x=0; x<head.biWidth; x++) {
p[BlindGetPixelIndex(x, y)]++;
}
}
double maxh = 0;
for (y=0; y<255; y++) if (maxh < p[y]) maxh = p[y];
threshold *= maxh;
int minc = 0;
while (minc<255 && p[minc]<=threshold) minc++;
int maxc = 255;
while (maxc>0 && p[maxc]<=threshold) maxc--;
if (minc == 0 && maxc == 255) return true;
if (minc >= maxc) return true;
// calculate LUT
BYTE lut[256];
for (x = 0; x <256; x++){
lut[x] = (BYTE)max(0,min(255,(255 * (x - minc) / (maxc - minc))));
}
for (y=0; y<head.biHeight; y++) {
if (info.nEscape) break;
info.nProgress = (long)(50.0+y*dbScaler);
for (x=0; x<head.biWidth; x++)
{
BlindSetPixelIndex(x, y, lut[BlindGetPixelIndex(x, y)]);
}
}
} else {
switch(method){
case 1:
{ // <nipper>
double p[256];
memset(p, 0, 256*sizeof(double));
for (y=0; y<head.biHeight; y++)
{
info.nProgress = (long)(y*dbScaler);
if (info.nEscape) break;
for (x=0; x<head.biWidth; x++) {
RGBQUAD color = BlindGetPixelColor(x, y);
p[color.rgbRed]++;
p[color.rgbBlue]++;
p[color.rgbGreen]++;
}
}
double maxh = 0;
for (y=0; y<255; y++) if (maxh < p[y]) maxh = p[y];
threshold *= maxh;
int minc = 0;
while (minc<255 && p[minc]<=threshold) minc++;
int maxc = 255;
while (maxc>0 && p[maxc]<=threshold) maxc--;
if (minc == 0 && maxc == 255) return true;
if (minc >= maxc) return true;
// calculate LUT
BYTE lut[256];
for (x = 0; x <256; x++){
lut[x] = (BYTE)max(0,min(255,(255 * (x - minc) / (maxc - minc))));
}
// normalize image
for (y=0; y<head.biHeight; y++) {
if (info.nEscape) break;
info.nProgress = (long)(50.0+y*dbScaler);
for (x=0; x<head.biWidth; x++)
{
RGBQUAD color = BlindGetPixelColor(x, y);
color.rgbRed = lut[color.rgbRed];
color.rgbBlue = lut[color.rgbBlue];
color.rgbGreen = lut[color.rgbGreen];
BlindSetPixelColor(x, y, color);
}
}
}
break;
case 2:
{ // <nipper>
double pR[256];
memset(pR, 0, 256*sizeof(double));
double pG[256];
memset(pG, 0, 256*sizeof(double));
double pB[256];
memset(pB, 0, 256*sizeof(double));
for (y=0; y<head.biHeight; y++)
{
info.nProgress = (long)(y*dbScaler);
if (info.nEscape) break;
for (long x=0; x<head.biWidth; x++) {
RGBQUAD color = BlindGetPixelColor(x, y);
pR[color.rgbRed]++;
pB[color.rgbBlue]++;
pG[color.rgbGreen]++;
}
}
double maxh = 0;
for (y=0; y<255; y++) if (maxh < pR[y]) maxh = pR[y];
double threshold2 = threshold*maxh;
int minR = 0;
while (minR<255 && pR[minR]<=threshold2) minR++;
int maxR = 255;
while (maxR>0 && pR[maxR]<=threshold2) maxR--;
maxh = 0;
for (y=0; y<255; y++) if (maxh < pG[y]) maxh = pG[y];
threshold2 = threshold*maxh;
int minG = 0;
while (minG<255 && pG[minG]<=threshold2) minG++;
int maxG = 255;
while (maxG>0 && pG[maxG]<=threshold2) maxG--;
maxh = 0;
for (y=0; y<255; y++) if (maxh < pB[y]) maxh = pB[y];
threshold2 = threshold*maxh;
int minB = 0;
while (minB<255 && pB[minB]<=threshold2) minB++;
int maxB = 255;
while (maxB>0 && pB[maxB]<=threshold2) maxB--;
if (minR == 0 && maxR == 255 && minG == 0 && maxG == 255 && minB == 0 && maxB == 255)
return true;
// calculate LUT
BYTE lutR[256];
BYTE range = maxR - minR;
if (range != 0) {
for (x = 0; x <256; x++){
lutR[x] = (BYTE)max(0,min(255,(255 * (x - minR) / range)));
}
} else lutR[minR] = minR;
BYTE lutG[256];
range = maxG - minG;
if (range != 0) {
for (x = 0; x <256; x++){
lutG[x] = (BYTE)max(0,min(255,(255 * (x - minG) / range)));
}
} else lutG[minG] = minG;
BYTE lutB[256];
range = maxB - minB;
if (range != 0) {
for (x = 0; x <256; x++){
lutB[x] = (BYTE)max(0,min(255,(255 * (x - minB) / range)));
}
} else lutB[minB] = minB;
// normalize image
for (y=0; y<head.biHeight; y++)
{
info.nProgress = (long)(50.0+y*dbScaler);
if (info.nEscape) break;
for (x=0; x<head.biWidth; x++)
{
RGBQUAD color = BlindGetPixelColor(x, y);
color.rgbRed = lutR[color.rgbRed];
color.rgbBlue = lutB[color.rgbBlue];
color.rgbGreen = lutG[color.rgbGreen];
BlindSetPixelColor(x, y, color);
}
}
}
break;
default:
{ // <dave>
double p[256];
memset(p, 0, 256*sizeof(double));
for (y=0; y<head.biHeight; y++)
{
info.nProgress = (long)(y*dbScaler);
if (info.nEscape) break;
for (x=0; x<head.biWidth; x++) {
RGBQUAD color = BlindGetPixelColor(x, y);
p[RGB2GRAY(color.rgbRed, color.rgbGreen, color.rgbBlue)]++;
}
}
double maxh = 0;
for (y=0; y<255; y++) if (maxh < p[y]) maxh = p[y];
threshold *= maxh;
int minc = 0;
while (minc<255 && p[minc]<=threshold) minc++;
int maxc = 255;
while (maxc>0 && p[maxc]<=threshold) maxc--;
if (minc == 0 && maxc == 255) return true;
if (minc >= maxc) return true;
// calculate LUT
BYTE lut[256];
for (x = 0; x <256; x++){
lut[x] = (BYTE)max(0,min(255,(255 * (x - minc) / (maxc - minc))));
}
for(y=0; y<head.biHeight; y++){
info.nProgress = (long)(50.0+y*dbScaler);
if (info.nEscape) break;
for(x=0; x<head.biWidth; x++){
RGBQUAD color = BlindGetPixelColor( x, y );
RGBQUAD yuvClr = RGBtoYUV(color);
yuvClr.rgbRed = lut[yuvClr.rgbRed];
color = YUVtoRGB(yuvClr);
BlindSetPixelColor( x, y, color );
}
}
}
}
}
return true;
}
bool CxImageICO::Decode(CxFile *hFile)
{
if (hFile==NULL) return false;
DWORD off = hFile->Tell(); //<yuandi>
int page=info.nFrame; //internal icon structure indexes
// read the first part of the header
ICONHEADER icon_header;
hFile->Read(&icon_header,sizeof(ICONHEADER),1);
icon_header.idType = my_ntohs(icon_header.idType);
icon_header.idCount = my_ntohs(icon_header.idCount);
// check if it's an icon or a cursor
if ((icon_header.idReserved == 0) && ((icon_header.idType == 1)||(icon_header.idType == 2))) {
info.nNumFrames = icon_header.idCount;
// load the icon descriptions
ICONDIRENTRY *icon_list = (ICONDIRENTRY *)malloc(icon_header.idCount * sizeof(ICONDIRENTRY));
int c;
for (c = 0; c < icon_header.idCount; c++) {
hFile->Read(icon_list + c, sizeof(ICONDIRENTRY), 1);
icon_list[c].wPlanes = my_ntohs(icon_list[c].wPlanes);
icon_list[c].wBitCount = my_ntohs(icon_list[c].wBitCount);
icon_list[c].dwBytesInRes = my_ntohl(icon_list[c].dwBytesInRes);
icon_list[c].dwImageOffset = my_ntohl(icon_list[c].dwImageOffset);
}
if ((page>=0)&&(page<icon_header.idCount)){
if (info.nEscape == -1) {
// Return output dimensions only
head.biWidth = icon_list[page].bWidth;
head.biHeight = icon_list[page].bHeight;
#if CXIMAGE_SUPPORT_PNG
if (head.biWidth==0 && head.biHeight==0)
{ // Vista icon support
hFile->Seek(off + icon_list[page].dwImageOffset, SEEK_SET);
CxImage png;
png.SetEscape(-1);
if (png.Decode(hFile,CXIMAGE_FORMAT_PNG)){
Transfer(png);
info.nNumFrames = icon_header.idCount;
}
}
#endif //CXIMAGE_SUPPORT_PNG
free(icon_list);
info.dwType = CXIMAGE_FORMAT_ICO;
return true;
}
// get the bit count for the colors in the icon <CoreyRLucier>
BITMAPINFOHEADER bih;
hFile->Seek(off + icon_list[page].dwImageOffset, SEEK_SET);
if (icon_list[page].bWidth==0 && icon_list[page].bHeight==0)
{ // Vista icon support
#if CXIMAGE_SUPPORT_PNG
CxImage png;
if (png.Decode(hFile,CXIMAGE_FORMAT_PNG)){
Transfer(png);
info.nNumFrames = icon_header.idCount;
}
SetType(CXIMAGE_FORMAT_ICO);
#endif //CXIMAGE_SUPPORT_PNG
}
else
{ // standard icon
hFile->Read(&bih,sizeof(BITMAPINFOHEADER),1);
bihtoh(&bih);
c = bih.biBitCount;
// allocate memory for one icon
Create(icon_list[page].bWidth,icon_list[page].bHeight, c, CXIMAGE_FORMAT_ICO); //image creation
// read the palette
RGBQUAD pal[256];
if (bih.biClrUsed)
hFile->Read(pal,bih.biClrUsed*sizeof(RGBQUAD), 1);
else
hFile->Read(pal,head.biClrUsed*sizeof(RGBQUAD), 1);
SetPalette(pal,head.biClrUsed); //palette assign
//read the icon
if (c<=24){
hFile->Read(info.pImage, head.biSizeImage, 1);
} else { // 32 bit icon
BYTE* buf=(BYTE*)malloc(4*head.biHeight*head.biWidth);
BYTE* src = buf;
hFile->Read(buf, 4*head.biHeight*head.biWidth, 1);
#if CXIMAGE_SUPPORT_ALPHA
if (!AlphaIsValid()) AlphaCreate();
#endif //CXIMAGE_SUPPORT_ALPHA
for (long y = 0; y < head.biHeight; y++) {
BYTE* dst = GetBits(y);
for(long x=0;x<head.biWidth;x++){
*dst++=src[0];
*dst++=src[1];
*dst++=src[2];
#if CXIMAGE_SUPPORT_ALPHA
AlphaSet(x,y,src[3]);
#endif //CXIMAGE_SUPPORT_ALPHA
src+=4;
}
}
free(buf);
}
// apply the AND and XOR masks
int maskwdt = ((head.biWidth+31) / 32) * 4; //line width of AND mask (always 1 Bpp)
int masksize = head.biHeight * maskwdt; //size of mask
BYTE *mask = (BYTE *)malloc(masksize);
if (hFile->Read(mask, masksize, 1)){
bool bGoodMask=false;
for (int im=0;im<masksize;im++){
if (mask[im]!=255){
bGoodMask=true;
break;
}
}
if (bGoodMask && c != 32){
#if CXIMAGE_SUPPORT_ALPHA
bool bNeedAlpha = false;
if (!AlphaIsValid()){
AlphaCreate();
} else {
bNeedAlpha=true; //32bit icon
}
int x,y;
for (y = 0; y < head.biHeight; y++) {
for (x = 0; x < head.biWidth; x++) {
if (((mask[y*maskwdt+(x>>3)]>>(7-x%8))&0x01)){
AlphaSet(x,y,0);
bNeedAlpha=true;
}
}
}
if (!bNeedAlpha) AlphaDelete();
#endif //CXIMAGE_SUPPORT_ALPHA
//check if there is only one transparent color
RGBQUAD cc,ct;
long* pcc = (long*)&cc;
long* pct = (long*)&ct;
int nTransColors=0;
int nTransIndex=0;
for (y = 0; y < head.biHeight; y++){
for (x = 0; x < head.biWidth; x++){
if (((mask[y*maskwdt+(x>>3)] >> (7-x%8)) & 0x01)){
cc = GetPixelColor(x,y,false);
if (nTransColors==0){
nTransIndex = GetPixelIndex(x,y);
nTransColors++;
ct = cc;
} else {
if (*pct!=*pcc){
nTransColors++;
}
}
}
}
}
if (nTransColors==1){
SetTransColor(ct);
SetTransIndex(nTransIndex);
#if CXIMAGE_SUPPORT_ALPHA
AlphaDelete(); //because we have a unique transparent color in the image
#endif //CXIMAGE_SUPPORT_ALPHA
}
// <vho> - Transparency support w/o Alpha support
if (c <= 8){ // only for icons with less than 256 colors (XP icons need alpha).
// find a color index, which is not used in the image
// it is almost sure to find one, bcs. nobody uses all possible colors for an icon
BYTE colorsUsed[256];
memset(colorsUsed, 0, sizeof(colorsUsed));
for (y = 0; y < head.biHeight; y++){
for (x = 0; x < head.biWidth; x++){
colorsUsed[BlindGetPixelIndex(x,y)] = 1;
}
}
int iTransIdx = -1;
for (x = (int)(head.biClrUsed-1); x>=0 ; x--){
if (colorsUsed[x] == 0){
iTransIdx = x; // this one is not in use. we may use it as transparent color
break;
}
}
// Go thru image and set unused color as transparent index if needed
if (iTransIdx >= 0){
bool bNeedTrans = false;
for (y = 0; y < head.biHeight; y++){
for (x = 0; x < head.biWidth; x++){
// AND mask (Each Byte represents 8 Pixels)
if (((mask[y*maskwdt+(x>>3)] >> (7-x%8)) & 0x01)){
// AND mask is set (!=0). This is a transparent part
SetPixelIndex(x, y, (BYTE)iTransIdx);
bNeedTrans = true;
}
}
}
// set transparent index if needed
if (bNeedTrans) SetTransIndex(iTransIdx);
#if CXIMAGE_SUPPORT_ALPHA
AlphaDelete(); //because we have a transparent color in the palette
#endif //CXIMAGE_SUPPORT_ALPHA
}
}
} else if(c != 32){
