www.pudn.com > imagescale---raw.zip > ImageGeometry.cpp
/////////////////////////////////////////////////////////////////////////////////
//
// ImageGeometry.cpp: implementation of the CImageGeometry class.
//
////////////////////////////////////////////////////////////////////////////////
// 版权所有(2002)
// Copyright(2002)
// 编写者: 向世明
// Author: Xiang Shiming
//图像几何变换
#include "stdafx.h"
#include "ImageGeometry.h"
#include "math.h"
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
IMPLEMENT_DYNAMIC(CImageGeometry, CImageProcess)
CImageGeometry::CImageGeometry()
{
m_dwOperation = IMAGE_GEOMETRY_TRANSLATE;
m_dwQuality = IMAGE_GEOMETRY_NEAREST_NEIGHBOR_INTERPOLATE;
}
CImageGeometry::~CImageGeometry()
{
}
#ifdef _DEBUG
void CImageGeometry::Dump(CDumpContext& dc) const
{
CImageProcess::Dump(dc);
}
void CImageGeometry::AssertValid() const
{
CImageProcess::AssertValid();
}
#endif
void CImageGeometry::SetQuality(DWORD dwQuality)
{
m_dwQuality = dwQuality;
}
///lpbySrcXY----传递源像素(x, y)的地址,
//x, y, 经过反向变换后得到的对应于原图像的象点的坐标
//nScanWidth, int nScanHeight, 源扫描宽度和扫描高度
PIXELCOLORRGB CImageGeometry::Interpolate(LPBYTE lpbySrcXY, int x, int y, float fu, float fv, int nScanWidth, int nScanHeight)
{
PIXELCOLORRGB rgb;
//行字节数, 可以将dwWidthBytes作为参数传递过来
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
switch(m_dwQuality)
{
case IMAGE_GEOMETRY_NEAREST_NEIGHBOR_INTERPOLATE :
{
BYTE* pbySrc = lpbySrcXY;
rgb.blue = *pbySrc++;
rgb.green = *pbySrc++;
rgb.red = *pbySrc++;
break;
}
case IMAGE_GEOMETRY_BILINEAR_INTERPOLATE :
{
//相邻的四个像素最右下角点的x, y坐标偏移量
int nx = 1;
int ny = 1;
if((x + 1) > (nScanWidth - 1)) nx = 0;
if((y + 1) > (nScanHeight - 1)) ny = 0;
//相邻四个像素的像素值
BYTE abyRed[2][2], abyGreen[2][2], abyBlue[2][2];
//像素点(x, y)的数据位置
BYTE* pbySrc = lpbySrcXY;
//获取像素数值.
//(x, y) = (x, y) + (0, 0)
abyBlue[0][0] = *pbySrc++;
abyGreen[0][0] = *pbySrc++;
abyRed[0][0] = *pbySrc++;
//(x + 1, y) = (x, y) + (1, 0)
pbySrc = (lpbySrcXY + nx * 4);
abyBlue[1][0] = *pbySrc++;
abyGreen[1][0] = *pbySrc++;
abyRed[1][0] = *pbySrc++;
//指向下一行数据
BYTE* pbySrcTemp = (lpbySrcXY + ny * dwWidthBytes);
//(x , y + 1) = (x, y) + (0, 1)
pbySrc = pbySrcTemp;
abyBlue[0][1] = *pbySrc++;
abyGreen[0][1] = *pbySrc++;
abyRed[0][1] = *pbySrc++;
//(x + 1, y + 1) = (x, y) + (1, 1)
pbySrc = pbySrcTemp + (4 * nx);
abyBlue[1][1] = *pbySrc++;
abyGreen[1][1] = *pbySrc++;
abyRed[1][1] = *pbySrc++;
rgb.red = (BYTE)(BOUND(((1 - fu) * (1 - fv) * ((float)abyRed[0][0]) +
(1 - fu) * fv * ((float)abyRed[0][1]) +
fu * (1 - fv) * ((float)abyRed[1][0]) +
fu * fv * ((float)abyRed[1][1])), 0, 255));
rgb.green = (BYTE)(BOUND(((1 - fu) * (1 - fv) * ((float)abyGreen[0][0]) +
(1 - fu) * fv * ((float)abyGreen[0][1]) +
fu * (1 - fv) * ((float)abyGreen[1][0]) +
fu * fv * ((float)abyGreen[1][1])), 0, 255));
rgb.blue = (BYTE)(BOUND(((1 - fu) * (1 - fv) * ((float)abyBlue[0][0]) +
(1 - fu) * fv * ((float)abyBlue[0][1]) +
fu * (1 - fv) * ((float)abyBlue[1][0]) +
fu * fv * ((float)abyBlue[1][1])), 0, 255));
break;
}
case IMAGE_GEOMETRY_THREE_ORDER_INTERPOLATE :
{
//像素坐标
int xx[4], yy[4];
//相邻四个像素的像素值
BYTE abyRed[4][4], abyGreen[4][4], abyBlue[4][4];
xx[0] = -1; xx[1] = 0; xx[2] = 1; xx[3] = 2;
yy[0] = -1; yy[1] = 0; yy[2] = 1; yy[3] = 2;
//保证合法
if((x - 1) < 0) xx[0] = 0;
if((x + 1) > (nScanWidth - 1)) xx[2] = 0;
if((x + 2) > (nScanWidth - 1)) xx[3] = ((xx[2] == 0) ? 0 : 1);
if((y - 1) < 0) yy[0] = 0;
if((y + 1) > (nScanHeight - 1)) yy[2] = 0;
if((y + 2) > (nScanHeight - 1)) yy[3] = ((yy[2] == 0) ? 0 : 1);
//像素点(x, y)的数据位置
//获取数据
int i;
for(i = 0;i < 4;i++)
{
//像素点(x, y)的数据位置
BYTE* pbySrcBase = lpbySrcXY + yy[i] * dwWidthBytes;
for(int j = 0;j < 4;j++)
{
BYTE* pbySrc = pbySrcBase + 4 * xx[j];
abyBlue[i][j] = *pbySrc++;
abyGreen[i][j] = *pbySrc++;
abyRed[i][j] = *pbySrc++;
}
}
//u, v向量
float afu[4], afv[4];
afu[0] = Sinxx(1.0f + fu);
afu[1] = Sinxx(fu);
afu[2] = Sinxx(1.0f - fu);
afu[3] = Sinxx(2.0f - fu);
afv[0] = Sinxx(1.0f + fv);
afv[1] = Sinxx(fv);
afv[2] = Sinxx(1.0f - fv);
afv[3] = Sinxx(2.0f - fv);
//矩阵乘向量的中间值
float afRed[4] = {0.0f, 0.0f, 0.0f, 0.0f};
float afGreen[4] = {0.0f, 0.0f, 0.0f, 0.0f};
float afBlue[4] = {0.0f, 0.0f, 0.0f, 0.0f};
for(i = 0;i < 4;i++)
{
for(int j = 0;j < 4;j++)
{
afRed[i] += afv[j] * abyRed[j][i];
afGreen[i] += afv[j] * abyGreen[j][i];
afBlue[i] += afv[j] * abyBlue[j][i];
}
}
rgb.red = (BYTE)(BOUND((afu[0] * afRed[0] + afu[1] * afRed[1] + afu[2] * afRed[2] +
afu[3] * afRed[3]), 0, 255));
rgb.green = (BYTE)(BOUND((afu[0] * afGreen[0] + afu[1] * afGreen[1] + afu[2] * afGreen[2] +
afu[3] * afGreen[3]), 0, 255));
rgb.blue = (BYTE)(BOUND((afu[0] * afBlue[0] + afu[1] * afBlue[1] + afu[2] * afBlue[2] +
afu[3] * afBlue[3]), 0, 255));
break;
}
default : break;
}//end switch
return rgb;
}
//该函数计算sin(x) / (x)
float CImageGeometry::Sinxx(float fx)
{
float fabsx = ABS(fx);
float fxx = fabsx * fabsx;
float fxxx = fxx * fabsx;
if(fabsx < 1.0f) return (1.0f - 2.0f * fxx + fxxx);
else if(fabsx < 2.0f)
return (4.0f - 8.0f * fabsx + 5.0f * fxx - fxxx);
else return 0.0f;
}
//lpbyBitsSrc32----传递源像素值,
//x, y, nWidth, nHeight, 定义区域的宽度
//nScanWidth, nScanHeight, 扫描宽度和扫描高度
//lpbyBitsDst32----存放最后缩放后的结果
//nWidthImgDst, nHeightImgDst缩放至多大
BOOL CImageGeometry::Scale(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32, int nWidthImgDst, int nHeightImgDst)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
ASSERT(nWidthImgDst != 0);
ASSERT(nHeightImgDst != 0);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
m_dwOperation = IMAGE_GEOMETRY_SCALE;
//有效区域的宽度和高度
int w = min(nWidth, nScanWidth - x);
int h = min(nHeight, nScanHeight - y);
//注意事项:
//第一:
//如果(w < nWidth), 或者(h < nHeight)则表示指的区域比能够有效获取数据的区域要大,
//这时程序将放大倍数, 使最后缩放的结果总能达到 nWidthImgDst 宽和 nHeightImgDst 高
//第二:
//fScalex, fScaley所表示的缩放比为真实缩放比的倒数
//之所以这样处理是由于, 作一次除法, 总比一次乘法要慢.
//宽度缩放比
float fScalex = (float)w / (float)nWidthImgDst;
float fScaley = (float)h / (float)nHeightImgDst;
//行字节数
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
//开始数据基索引
DWORD dwBaseIndex = y * dwWidthBytes + 4 * x;
//指向目标数据
BYTE* pbyDst = lpbyBitsDst32;
//完成变换
for(int i = 0; i < nHeightImgDst;i++)
{
//反向变换后获得的浮点y值
float fYInverse = i * fScaley;
//取整
int yy = (int)fYInverse;
//坐标差值
float fv = fYInverse - yy;
//对应于原图像的y坐标
yy += y;
BYTE* pbySrc = lpbyBitsSrc32 + yy * dwWidthBytes;
for(int j = 0;j < nWidthImgDst;j++)
{
//反向变换后获得的浮点x值
float fXInverse = j * fScalex;
//取整
int xx = (int)fXInverse;
//坐标差值
float fu = fXInverse - xx;
//对应于原图像的y坐标
xx += x;
//获取数据
BYTE* pbyCurrent = pbySrc + 4 * xx;
PIXELCOLORRGB rgb = Interpolate(pbyCurrent, xx, yy, fu, fv, nScanWidth, nScanHeight);
*pbyDst++ = rgb.blue;
*pbyDst++ = rgb.green;
*pbyDst++ = rgb.red;
//alpha数据由外部填充.
pbyDst++;
}
}
return TRUE;
}
//顺时针旋转90度
//包括 n * 360 - 90 度
//x, y, nWidth, nHeight-----定义子区域
//lpbyBitsDst32----大小为nWidth * nHeight * 4;
//nScanWidth-------源图像扫描宽度
//nScanHeight------源图像扫描高度
BOOL CImageGeometry::RotateCW90(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
m_dwOperation = IMAGE_GEOMETRY_ROTATE_CW_90;
//行字节数
DWORD dwWidthBytes = (DWORD)nScanWidth * 4; //No 10
//指定区域最后一行第一列处的数据地址.
BYTE* pbySrcBase = lpbyBitsSrc32 + (y + nHeight - 1) * dwWidthBytes + 4 * x;
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
for(int i = 0;i < nWidth;i++)
{
//从底向上按列获取数据
//逐渐向右移动
BYTE* pbySrc = pbySrcBase;
for(int j = 0;j < nHeight;j++)
{
BYTE* pbyCurrent = pbySrc;
*pbyDst++ = *pbyCurrent++;
*pbyDst++ = *pbyCurrent++;
*pbyDst++ = *pbyCurrent++;
pbyDst++;
pbySrc -= dwWidthBytes;
}
pbySrcBase += 4;
}
return TRUE;
}
//逆时针旋转90度
//lpbyBitsDst32----大小为nWidth * nHeight * 4;
BOOL CImageGeometry::RotateCCW90(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
m_dwOperation = IMAGE_GEOMETRY_ROTATE_CCW_90;
//行字节数
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
//指定区域第一行最后一列开始地址.
BYTE* pbySrcBase = lpbyBitsSrc32 + y * dwWidthBytes + 4 * (x + nWidth - 1);
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
for(int i = 0;i < nWidth;i++)
{
//从上向下按列获取数据
//逐渐向左移动
BYTE* pbySrc = pbySrcBase;
for(int j = 0;j < nHeight;j++)
{
BYTE* pbyCurrent = pbySrc;
*pbyDst++ = *pbyCurrent++;
*pbyDst++ = *pbyCurrent++;
*pbyDst++ = *pbyCurrent++;
pbyDst++;
pbySrc += dwWidthBytes;
}
pbySrcBase -= 4;
}
return TRUE;
}
BOOL CImageGeometry::Rotate180(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
//行字节数
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
m_dwOperation = IMAGE_GEOMETRY_ROTATE_180;
//指定区域最后一行最后一列开始地址.
BYTE* pbySrcBase = lpbyBitsSrc32 + (y + nHeight - 1) * dwWidthBytes + 4 * (x + nWidth - 1);
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
for(int i = 0;i < nHeight;i++)
{
//
//逐渐向左移动
BYTE* pbySrc = pbySrcBase;
for(int j = 0;j < nWidth;j++)
{
*pbyDst++ = *pbySrc++;
*pbyDst++ = *pbySrc++;
*pbyDst++ = *pbySrc++;
pbyDst++;
pbySrc -= 7;
/*
//下列代码是等价的.
BYTE* pbyCurrent = pbySrc;
*pbyDst++ = *pbyCurrent++;
*pbyDst++ = *pbyCurrent++;
*pbyDst++ = *pbyCurrent++;
pbyDst++;
pbySrc -= 4;
*/
}
pbySrcBase -= dwWidthBytes;
}
return TRUE;
}
//旋转..., -360, 0, 360, ...度
BOOL CImageGeometry::Rotate0(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
m_dwOperation = IMAGE_GEOMETRY_ROTATE_0;
//行字节数(源图像)
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
//行字节数(目标子图像)
DWORD dwWidtgBytesDst = (DWORD)nWidth * 4;
//指定区域第一行第一列开始地址.
BYTE* pbySrcBase = lpbyBitsSrc32 + y * dwWidthBytes + 4 * x;
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
for(int i = 0; i < nHeight; i++)
{
::CopyMemory(pbyDst, pbySrcBase, dwWidtgBytesDst);
pbySrcBase += dwWidthBytes;
pbyDst += dwWidtgBytesDst;
}
return TRUE;
}
//lpbyBitsSrc32----传递源像素值,
//x, y, nWidth, nHeight, 定义区域的宽度
//nScanWidth, nScanHeight, 扫描宽度和扫描高度
//lpbyBitsDst32----存放最后缩放后的结果
//fTheta ---- 旋转角度
//nWidthImgDst, nHeightDst旋转后的尺寸, 事实上它们可以通过nWidth, nHeight和fTheta计算出来.
BOOL CImageGeometry::Rotate(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32, float fTheta, int nWidthImgDst, int nHeightImgDst)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
m_dwOperation = IMAGE_GEOMETRY_ROTATE;
//将角度转化成弧度
float fRadTheta = (float)(fTheta * PIE / 180.0);
//计算其三角函数值
float fSinTheta = (float)sin(fRadTheta);
float fCosTheta = (float)cos(fRadTheta);
///////////////////////////////////////////////////////
//首先考查是否是旋转特殊的角度.
///////////////////////////////////////////////////////
if((nWidthImgDst == nHeight) && (nHeightImgDst == nWidth))
{
// ..., -270, 90, 450, ...,
if(fSinTheta > 0.99f)
return RotateCCW90(lpbyBitsSrc32, x, y, nWidth, nHeight, nScanWidth, nScanHeight, lpbyBitsDst32);
// ..., -450, -90, 270, ...,
else if(fSinTheta < -0.99f)
return RotateCW90(lpbyBitsSrc32, x, y, nWidth, nHeight, nScanWidth, nScanHeight, lpbyBitsDst32);
}
if((nWidthImgDst == nWidth) && (nHeightImgDst == nHeight))
{
// ..., -540, -180, 180, 540, ...,
if(fCosTheta < -0.99f)
return Rotate180(lpbyBitsSrc32, x, y, nWidth, nHeight, nScanWidth, nScanHeight, lpbyBitsDst32);
// ..., -360, 0, 360,
else if (fCosTheta > 0.99f)
return Rotate0(lpbyBitsSrc32, x, y, nWidth, nHeight, nScanWidth, nScanHeight, lpbyBitsDst32);
}
//////////////////////////////////////////////////
//处理非特殊角度
//////////////////////////////////////////////////
//绝对旋转中心, 相对于原图像坐标系统.
int nAbsCenterX = x + nWidth / 2;
int nAbsCenterY = y + nHeight / 2;
//相对旋转中心, 它们具有相同的x, y坐标.相对于目标图像
int nRelCenterX = nWidthImgDst / 2;
int nRelCenterY = nHeightImgDst / 2;
//行字节数
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
//开始计算
//按行进行扫描计算
for(int i = 0;i < nHeightImgDst;i++)//y
{
//右手直角坐标系下, 坐标值为 i 的纵坐标表示
int yy = nRelCenterY - i;
for(int j = 0; j < nWidthImgDst;j++)//x
{
//右手直角坐标系下, 坐标值为 j 的横坐标表示
int xx = j - nRelCenterX;
//进行反向变换, 旋转角度: -theta
float fXInverse = xx * fCosTheta + yy * fSinTheta;
float fYInverse = yy * fCosTheta - xx * fSinTheta;
//变成左手坐标系
fYInverse = -fYInverse;
fXInverse += nAbsCenterX;
fYInverse += nAbsCenterY;
//近邻坐标值
//
int nNearX = (int)fXInverse;
int nNearY = (int)fYInverse;
if((nNearX >= x) && (nNearX <= (x + nWidth - 1)) &&
(nNearY >= y) && (nNearY <= (y + nHeight - 1)))
{
//插值参数
float fu = fXInverse - nNearX;
float fv = fYInverse - nNearY;
//近邻点的地址
BYTE* pbySrc = lpbyBitsSrc32 + nNearY * dwWidthBytes + 4 * nNearX;
PIXELCOLORRGB rgb = Interpolate(pbySrc, nNearX, nNearY, fu, fv, nScanWidth, nScanHeight);
*pbyDst++ = rgb.blue;
*pbyDst++ = rgb.green;
*pbyDst++ = rgb.red;
pbyDst++;
}
else
pbyDst += 4;
}
}
return TRUE;
}
//水平镜象,但是镜象轴为 Y 轴
BOOL CImageGeometry::MirrorY(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
m_dwOperation = IMAGE_GEOMETRY_MIRROR_Y;
//行字节数
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
//指定区域最后一行最后一列开始地址.
BYTE* pbySrcBase = lpbyBitsSrc32 + y * dwWidthBytes + 4 * (x + nWidth - 1);
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
for(int i = 0;i < nHeight;i++)
{
//从上向下按列获取数据
//逐渐向左移动
BYTE* pbySrc = pbySrcBase;
for(int j = 0;j < nWidth;j++)
{
*pbyDst++ = *pbySrc++;
*pbyDst++ = *pbySrc++;
*pbyDst++ = *pbySrc++;
pbyDst++;
pbySrc -= 7;
}
pbySrcBase += dwWidthBytes;
}
return TRUE;
}
//垂直镜象,但是镜象轴为 X 轴
BOOL CImageGeometry::MirrorX(LPBYTE lpbyBitsSrc32, int x, int y, int nWidth, int nHeight, int nScanWidth, int nScanHeight, LPBYTE lpbyBitsDst32)
{
//第一步, 进行参数合法性检测
ASSERT(lpbyBitsSrc32);
ASSERT(lpbyBitsDst32);
if((x > (nScanWidth - 1)) || (y > (nScanHeight - 1))) return FALSE;
//有效区域的宽度和高度
//请注意, 这时, 宽度和高度不得随意超过有效宽度和高度.
if(nWidth > (nScanWidth - x))
{
::AfxMessageBox("The width of the area you defined is not obtained!");
return FALSE;
}
if(nHeight > (nScanHeight - y))
{
::AfxMessageBox("The height of the area you defined is not obtained!");
return FALSE;
}
m_dwOperation = IMAGE_GEOMETRY_MIRROR_X;
//行字节数(源图像)
DWORD dwWidthBytes = (DWORD)nScanWidth * 4;
//行字节数(目标子图像)
DWORD dwWidtgBytesDst = (DWORD)nWidth * 4;
//指定区域最后一行第一列开始地址.
BYTE* pbySrcBase = lpbyBitsSrc32 + (y + nHeight - 1) * dwWidthBytes + 4 * x;
//目的地地址
BYTE* pbyDst = lpbyBitsDst32;
for(int i = 0;i < nHeight;i++)
{
//从下向向按行获取数据
::CopyMemory(pbyDst, pbySrcBase, dwWidtgBytesDst);
pbyDst += dwWidtgBytesDst;
pbySrcBase -= dwWidthBytes;
}
return TRUE;
}