图像拉伸，放大缩小算法函数
2008-12-30 13:15
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平滑放大缩小拉伸图像，本函数同时具有很高的效率。
其中BITMAP24结构和BITMAP 结构类似，在这里你可以假设两者相同。
pMapX,pMapY用于建立积卷映射表，同时将浮点运算转换成浮点运算。
void ImageStretch(BITMAP24 & dest,const BITMAP24 & src)
{
ASSERT(dest.bmWidth>0 && dest.bmHeight>0);
ASSERT(src.bmWidth>0 && src.bmHeight>0);
double fZoomX = (double)dest.bmWidth/(double)src.bmWidth;
double fZoomY = (double)dest.bmHeight/(double)src.bmHeight;
LONG i;
POINTMAP * pMapX;
POINTMAP * pMapY;
double fMin,fMax;
pMapX = CImageDataMgr::instance().AllocXPointMap(dest.bmWidth);
pMapY = CImageDataMgr::instance().AllocYPointMap(dest.bmHeight);
// 初始化pMapX
if (fZoomX<1.0f)
{
for (i=0;i<dest.bmWidth;i++)
{
fMin = i/fZoomX;
fMax = (i+1)/fZoomX;
pMapX[i].ps = (int)fMin;
pMapX[i].pe = (int)fMax;
if (pMapX[i].ps>=src.bmWidth) pMapX[i].ps=src.bmWidth-1;
if (pMapX[i].pe>=src.bmWidth) pMapX[i].pe=src.bmWidth-1;
pMapX[i].ws = (int)((pMapX[i].ps+1.0f-fMin)*fZoomX*256);
pMapX[i].we = (int)((fMax-pMapX[i].pe)*fZoomX*256);
pMapX[i].wi = 256-pMapX[i].ws-pMapX[i].we;
}
} else if (fZoomX==1.0f)
{
for (i=0;i<dest.bmWidth;i++)
{
pMapX[i].ps = i;
pMapX[i].pe = i;
pMapX[i].ws = 256;
pMapX[i].we = 0;
}
} else if (fZoomX>1.0f)
{
for (i=0;i<dest.bmWidth;i++)
{
fMin = i/fZoomX;
pMapX[i].ps = (LONG)fMin;
pMapX[i].pe = pMapX[i].ps+1;
if (pMapX[i].ps>=src.bmWidth) pMapX[i].ps=src.bmWidth-1;
if (pMapX[i].pe>=src.bmWidth) pMapX[i].pe=src.bmWidth-1;
fMin -= pMapX[i].ps;
pMapX[i].we = (LONG)(fMin * 256);
pMapX[i].ws = 256 - pMapX[i].we;
}
}
// 初始化pMapY
if (fZoomY<1.0f)
{
for (i=0;i<dest.bmHeight;i++)
{
fMin = i/fZoomY;
fMax = (i+1)/fZoomY;
pMapY[i].ps = (int)fMin;
pMapY[i].pe = (int)fMax;
if (pMapY[i].ps>=src.bmHeight) pMapY[i].ps=src.bmHeight-1;
if (pMapY[i].pe>=src.bmHeight) pMapY[i].pe=src.bmHeight-1;
pMapY[i].ws = (int)((pMapY[i].ps+1.0f-fMin)*fZoomY*256);
pMapY[i].we = (int)((fMax-pMapY[i].pe)*fZoomY*256);
pMapY[i].wi = 256-pMapY[i].ws-pMapY[i].we;
}
} else if (fZoomY==1.0f)
{
for (i=0;i<dest.bmHeight;i++)
{
pMapY[i].ps = i;
pMapY[i].pe = i;
pMapY[i].ws = 256;
pMapY[i].we = 0;
}
} else if (fZoomY>1.0f)
{
for (i=0;i<dest.bmHeight;i++)
{
fMin = i/fZoomY;
pMapY[i].ps = (LONG)fMin;
pMapY[i].pe = pMapY[i].ps+1;
if (pMapY[i].ps>=src.bmWidth) pMapY[i].ps=src.bmWidth-1;
if (pMapY[i].pe>=src.bmWidth) pMapY[i].pe=src.bmWidth-1;
fMin -= pMapY[i].ps;
pMapY[i].we = (LONG)(fMin * 256);
pMapY[i].ws = 256 - pMapY[i].we;
}
}
LONG xd,yd;
LONG ld,pd;
LONG ls, ps,pe,pi;
LONG psY,peY,psX,peX;
LONG wsY,weY,wiY;
LONG wsX,weX,wiX;
LONG rvs, gvs, bvs;
LONG rve, gve, bve;
LONG rvi, gvi, bvi;
LONG rv, gv, bv;
BYTE * bsDest = dest.bmBits;
BYTE * bsSrc = src.bmBits;
LONG xi,yi;
ld = 0;
for (yd=0;yd<dest.bmHeight;yd++)
{
psY = pMapY[yd].ps;
peY = pMapY[yd].pe;
wsY = pMapY[yd].ws;
weY = pMapY[yd].we;
wiY = pMapY[yd].wi;
pd = ld;
for (xd=0;xd<dest.bmWidth;xd++)
{
psX = pMapX[xd].ps;
peX = pMapX[xd].pe;
wsX = pMapX[xd].ws;
weX = pMapX[xd].we;
wiX = pMapX[xd].wi;
if (psY==peY)
{
ls = src.bmWidthBytes * psY;
ps = ls + psX * 3;
if (psX==peX)
{
bsDest[pd] = bsSrc[ps];
bsDest[pd+1] = bsSrc[ps+1];
bsDest[pd+2] = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bsDest[pd] = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
bsDest[pd+1] = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
bsDest[pd+2] = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bsDest[pd] = (BYTE)(bv>>8);
bsDest[pd+1] = (BYTE)(gv>>8);
bsDest[pd+2] = (BYTE)(rv>>8);
}
} else if (peY-1==psY)
{
ls = src.bmWidthBytes * psY;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bvs = bv;
gvs = gv;
rvs = rv;
ls = peY * src.bmWidthBytes;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
e023
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bve = bv;
gve = gv;
rve = rv;
bsDest[pd] = (BYTE)((bvs * wsY + bve * weY)>>8);
bsDest[pd+1] = (BYTE)((gvs * wsY + gve * weY)>>8);
bsDest[pd+2] = (BYTE)((rvs * wsY + rve * weY)>>8);
} else {
// 计算中间部分 bvi;
bvi = 0, gvi = 0, rvi = 0;
for (yi = psY+1; yi<peY;yi++)
{
ls = src.bmWidthBytes * yi;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bvi += bv;
gvi += gv;
rvi += rv;
}
// 计算vs
ls = src.bmWidthBytes * psY;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bvs = bv;
gvs = gv;
rvs = rv;
ls = src.bmWidthBytes * peY;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bve = bv;
gve = gv;
rve = rv;
bv = bvs * wsY + bvi * wiY / (peY - psY -1) + bve * weY;
gv = gvs * wsY + gvi * wiY / (peY - psY -1) + gve * weY;
rv = rvs * wsY + rvi * wiY / (peY - psY -1) + rve * weY;
bsDest[pd] = (BYTE)(bv>>8);
bsDest[pd+1] = (BYTE)(gv>>8);
bsDest[pd+2] = (BYTE)(rv>>8);
}
pd += 3;
}
ld += dest.bmWidthBytes;
}
}
其中BITMAP24结构和BITMAP 结构类似，在这里你可以假设两者相同。
pMapX,pMapY用于建立积卷映射表，同时将浮点运算转换成浮点运算。
void ImageStretch(BITMAP24 & dest,const BITMAP24 & src)
{
ASSERT(dest.bmWidth>0 && dest.bmHeight>0);
ASSERT(src.bmWidth>0 && src.bmHeight>0);
double fZoomX = (double)dest.bmWidth/(double)src.bmWidth;
double fZoomY = (double)dest.bmHeight/(double)src.bmHeight;
LONG i;
POINTMAP * pMapX;
POINTMAP * pMapY;
double fMin,fMax;
pMapX = CImageDataMgr::instance().AllocXPointMap(dest.bmWidth);
pMapY = CImageDataMgr::instance().AllocYPointMap(dest.bmHeight);
// 初始化pMapX
if (fZoomX<1.0f)
{
for (i=0;i<dest.bmWidth;i++)
{
fMin = i/fZoomX;
fMax = (i+1)/fZoomX;
pMapX[i].ps = (int)fMin;
pMapX[i].pe = (int)fMax;
if (pMapX[i].ps>=src.bmWidth) pMapX[i].ps=src.bmWidth-1;
if (pMapX[i].pe>=src.bmWidth) pMapX[i].pe=src.bmWidth-1;
pMapX[i].ws = (int)((pMapX[i].ps+1.0f-fMin)*fZoomX*256);
pMapX[i].we = (int)((fMax-pMapX[i].pe)*fZoomX*256);
pMapX[i].wi = 256-pMapX[i].ws-pMapX[i].we;
}
} else if (fZoomX==1.0f)
{
for (i=0;i<dest.bmWidth;i++)
{
pMapX[i].ps = i;
pMapX[i].pe = i;
pMapX[i].ws = 256;
pMapX[i].we = 0;
}
} else if (fZoomX>1.0f)
{
for (i=0;i<dest.bmWidth;i++)
{
fMin = i/fZoomX;
pMapX[i].ps = (LONG)fMin;
pMapX[i].pe = pMapX[i].ps+1;
if (pMapX[i].ps>=src.bmWidth) pMapX[i].ps=src.bmWidth-1;
if (pMapX[i].pe>=src.bmWidth) pMapX[i].pe=src.bmWidth-1;
fMin -= pMapX[i].ps;
pMapX[i].we = (LONG)(fMin * 256);
pMapX[i].ws = 256 - pMapX[i].we;
}
}
// 初始化pMapY
if (fZoomY<1.0f)
{
for (i=0;i<dest.bmHeight;i++)
{
fMin = i/fZoomY;
fMax = (i+1)/fZoomY;
pMapY[i].ps = (int)fMin;
pMapY[i].pe = (int)fMax;
if (pMapY[i].ps>=src.bmHeight) pMapY[i].ps=src.bmHeight-1;
if (pMapY[i].pe>=src.bmHeight) pMapY[i].pe=src.bmHeight-1;
pMapY[i].ws = (int)((pMapY[i].ps+1.0f-fMin)*fZoomY*256);
pMapY[i].we = (int)((fMax-pMapY[i].pe)*fZoomY*256);
pMapY[i].wi = 256-pMapY[i].ws-pMapY[i].we;
}
} else if (fZoomY==1.0f)
{
for (i=0;i<dest.bmHeight;i++)
{
pMapY[i].ps = i;
pMapY[i].pe = i;
pMapY[i].ws = 256;
pMapY[i].we = 0;
}
} else if (fZoomY>1.0f)
{
for (i=0;i<dest.bmHeight;i++)
{
fMin = i/fZoomY;
pMapY[i].ps = (LONG)fMin;
pMapY[i].pe = pMapY[i].ps+1;
if (pMapY[i].ps>=src.bmWidth) pMapY[i].ps=src.bmWidth-1;
if (pMapY[i].pe>=src.bmWidth) pMapY[i].pe=src.bmWidth-1;
fMin -= pMapY[i].ps;
pMapY[i].we = (LONG)(fMin * 256);
pMapY[i].ws = 256 - pMapY[i].we;
}
}
LONG xd,yd;
LONG ld,pd;
LONG ls, ps,pe,pi;
LONG psY,peY,psX,peX;
LONG wsY,weY,wiY;
LONG wsX,weX,wiX;
LONG rvs, gvs, bvs;
LONG rve, gve, bve;
LONG rvi, gvi, bvi;
LONG rv, gv, bv;
BYTE * bsDest = dest.bmBits;
BYTE * bsSrc = src.bmBits;
LONG xi,yi;
ld = 0;
for (yd=0;yd<dest.bmHeight;yd++)
{
psY = pMapY[yd].ps;
peY = pMapY[yd].pe;
wsY = pMapY[yd].ws;
weY = pMapY[yd].we;
wiY = pMapY[yd].wi;
pd = ld;
for (xd=0;xd<dest.bmWidth;xd++)
{
psX = pMapX[xd].ps;
peX = pMapX[xd].pe;
wsX = pMapX[xd].ws;
weX = pMapX[xd].we;
wiX = pMapX[xd].wi;
if (psY==peY)
{
ls = src.bmWidthBytes * psY;
ps = ls + psX * 3;
if (psX==peX)
{
bsDest[pd] = bsSrc[ps];
bsDest[pd+1] = bsSrc[ps+1];
bsDest[pd+2] = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bsDest[pd] = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
bsDest[pd+1] = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
bsDest[pd+2] = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bsDest[pd] = (BYTE)(bv>>8);
bsDest[pd+1] = (BYTE)(gv>>8);
bsDest[pd+2] = (BYTE)(rv>>8);
}
} else if (peY-1==psY)
{
ls = src.bmWidthBytes * psY;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bvs = bv;
gvs = gv;
rvs = rv;
ls = peY * src.bmWidthBytes;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
e023
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bve = bv;
gve = gv;
rve = rv;
bsDest[pd] = (BYTE)((bvs * wsY + bve * weY)>>8);
bsDest[pd+1] = (BYTE)((gvs * wsY + gve * weY)>>8);
bsDest[pd+2] = (BYTE)((rvs * wsY + rve * weY)>>8);
} else {
// 计算中间部分 bvi;
bvi = 0, gvi = 0, rvi = 0;
for (yi = psY+1; yi<peY;yi++)
{
ls = src.bmWidthBytes * yi;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bvi += bv;
gvi += gv;
rvi += rv;
}
// 计算vs
ls = src.bmWidthBytes * psY;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bvs = bv;
gvs = gv;
rvs = rv;
ls = src.bmWidthBytes * peY;
ps = ls + psX * 3;
if (psX==peX)
{
bv = bsSrc[ps];
gv = bsSrc[ps+1];
rv = bsSrc[ps+2];
} else if (peX-1==psX)
{
pe = ps + 3;
bv = (BYTE)((bsSrc[ps] * wsX
+ bsSrc[pe] * weX)>>8);
gv = (BYTE)((bsSrc[ps+1] * wsX
+ bsSrc[pe+1] * weX)>>8);
rv = (BYTE)((bsSrc[ps+2] * wsX
+ bsSrc[pe+2] * weX)>>8);
} else {
bv = 0, gv = 0, rv = 0;
pi = ps +3;
for (xi = psX+1;xi<peX;xi++)
{
bv += bsSrc[pi];
gv += bsSrc[pi+1];
rv += bsSrc[pi+2];
pi +=3;
}
bv = bv*wiX/(peX-psX-1);
gv = gv*wiX/(peX-psX-1);
rv = rv*wiX/(peX-psX-1);
bv += bsSrc[ps] * wsX;
gv += bsSrc[ps+1] * wsX;
rv += bsSrc[ps+2] * wsX;
pe = ls + peX * 3;
bv += bsSrc[pe] * weX;
gv += bsSrc[pe+1] * weX;
rv += bsSrc[pe+2] * weX;
bv = bv>>8;
gv = gv>>8;
rv = rv>>8;
}
bve = bv;
gve = gv;
rve = rv;
bv = bvs * wsY + bvi * wiY / (peY - psY -1) + bve * weY;
gv = gvs * wsY + gvi * wiY / (peY - psY -1) + gve * weY;
rv = rvs * wsY + rvi * wiY / (peY - psY -1) + rve * weY;
bsDest[pd] = (BYTE)(bv>>8);
bsDest[pd+1] = (BYTE)(gv>>8);
bsDest[pd+2] = (BYTE)(rv>>8);
}
pd += 3;
}
ld += dest.bmWidthBytes;
}
}
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