图像的膨胀与腐蚀实现

#include <iostream>#include <string>#include "gdal_priv.h"using namespace std;//图像的膨胀//算法的实现依然有重复的地方，会造成空间和时间上的浪费，但是效果还可以，暂定如此，如有好的算法再进行改进void Expand(unsigned char* date,unsigned char* ExpandImage,int Width,int Height){    int x, y;    int Direction[8][2] = {-1, -1, 0, -1, 1, -1, 1, 0, 1, 1, 0, 1, -1, 1, -1, 0};    int Index;    for(int i = 1;i < Height - 1;++i)    {        for(int j = 1;j < Width - 1;++j)        {            if(date[i * Width + j] == 255)            {                for(int k = 0;k < 8;++k)                {                    x = i + Direction[k][0];                    y = j + Direction[k][1];                    Index = x * Width + y;                    ExpandImage[Index] = 255;                }            }        }    }    return;}//图像的腐蚀void Erosion(unsigned char* date,unsigned char* ErosionImage,int Width,int Height){    int x, y;    int Direction[8][2] = {-1, -1, 0, -1, 1, -1, 1, 0, 1, 1, 0, 1, -1, 1, -1, 0};    int Index;    for(int i = 1;i < Height - 1;++i)    {        for(int j = 1;j < Width - 1;++j)        {            if(date[i * Width + j] == 0)            {                for(int k = 0;k < 8;++k)                {                    x = i + Direction[k][0];                    y = j + Direction[k][1];                    Index = x * Width + y;                    ErosionImage[Index] = 0;                }            }        }    }    return;}int main(){    GDALAllRegister();    CPLSetConfigOption("GDAL_FILENAME_IS_UTF8","NO");    string str1="1.1.bmp";    string str2="1.2.tif";    string str3 = "1.3.tif";    GDALDataset* pInDataset=(GDALDataset*)GDALOpen(str1.data() ,GA_ReadOnly);    if(pInDataset == nullptr)    {        cout<<"未找到输入图像"<<endl;        getchar();        return 1;    }    int Width=pInDataset->GetRasterXSize();    int Height = pInDataset->GetRasterYSize();    int band = pInDataset->GetRasterCount();    double dGeoTrans[6]={};    pInDataset->GetGeoTransform(dGeoTrans);    const char* cProjectionRef = pInDataset->GetProjectionRef();    unsigned char* date = new unsigned char[Width * Height];    GDALRasterBand* pRasterBand = pInDataset->GetRasterBand(1);    CPLErr err=pRasterBand->RasterIO(GF_Read ,0 ,0 ,Width ,Height ,date ,Width ,Height ,GDT_Byte ,0 ,0);    //生成对于图像膨胀的图像    unsigned char* ExpandImage = new unsigned char[Width * Height];    memset(ExpandImage,0,sizeof(unsigned char) * Width * Height);    Expand(date ,ExpandImage,Width ,Height);    GDALDriver* pExpandDriver = GetGDALDriverManager()->GetDriverByName("GTiff");    GDALDataset* pOutExpandDataset = pExpandDriver->Create(str2.data() ,Width ,Height ,1 ,GDT_Byte ,NULL);    pOutExpandDataset->SetGeoTransform(dGeoTrans);    pOutExpandDataset->SetProjection(cProjectionRef);    GDALRasterBand* pOutExpandRasterband=pOutExpandDataset->GetRasterBand(1);    pOutExpandRasterband->RasterIO(GF_Write ,0 ,0 ,Width ,Height ,ExpandImage ,Width ,Height ,GDT_Byte ,0 ,0);    //生成对于图像腐蚀的图像，注意初始赋值时的不同    unsigned char* ErosionImage = new unsigned char[Width * Height];    memset(ErosionImage,255,sizeof(unsigned char) * Width * Height);    Erosion(date,ErosionImage,Width,Height);    GDALDriver* pDriver = GetGDALDriverManager()->GetDriverByName("GTiff");    GDALDataset* pOutDataset = pDriver->Create(str3.data() ,Width ,Height ,1 ,GDT_Byte ,NULL);    pOutDataset->SetGeoTransform(dGeoTrans);    pOutDataset->SetProjection(cProjectionRef);    GDALRasterBand* pOutRasterband=pOutDataset->GetRasterBand(1);    pOutRasterband->RasterIO(GF_Write ,0 ,0 ,Width ,Height ,ErosionImage ,Width ,Height ,GDT_Byte ,0 ,0);    GDALClose(pOutDataset);    GDALClose(pOutExpandDataset);    GDALClose(pInDataset);    GetGDALDriverManager()->DeregisterDriver(pDriver);    GetGDALDriverManager()->DeregisterDriver(pExpandDriver);    delete date;    delete ExpandImage;    delete ErosionImage;    return 0;}

通过腐蚀和膨胀可以实现开运算和闭运算。
开运算：先腐蚀再膨胀
闭运算：先膨胀再腐蚀

然后弱小目标检测：闭运算减去开运算

具体实现：

unsigned char* ExpandImage = new unsigned char[Width * Height];memset(ExpandImage,0,sizeof(unsigned char) * Width * Height);Expand(date ,ExpandImage,Width ,Height);unsigned char* ErosionImage = new unsigned char[Width * Height];memset(ErosionImage,255,sizeof(unsigned char) * Width * Height);Erosion(date,ErosionImage,Width,Height);unsigned char* OpeningImage = new unsigned char[Width * Height];memset(OpeningImage,0,sizeof(unsigned char) * Width * Height);Expand(ErosionImage,OpeningImage,Width,Height);unsigned char* ClosingImage = new unsigned char[Width * Height];memset(ClosingImage,255,sizeof(unsigned char) * Width * Height);Erosion(ExpandImage,ClosingImage,Width,Height);//弱小目标检测：闭运算减去开运算unsigned char* ResultImage = new unsigned char[Width * Height];memset(ResultImage,255,sizeof(unsigned char) * Width * Height);//ResultImage即为弱小目标检测结果Subtraction(ResultImage,ClosingImage,OpeningImage,Width,Height);