GDAL 栅格数据转矢量数据

来源：互联网发布：无主之地优化编辑：程序博客网时间：2024/05/16 19:16

网上有不少关于栅格转矢量的代码，今天参考了别人的代码，写出了一个完整的程序：

#include "gdal_priv.h"#include "ogrsf_frmts.h" //for ogr#include "gdal_alg.h"  //for GDALPolygonize#include "cpl_conv.h" //for CPLMalloc() int ImagePolygonize(const char * pszSrcFile,const char* pszDstFile,const char* pszFormat);int main(){   const char* pszSrcFile = "H:\\GDAL文件\\gdal栅格矢量化\\classify_bitmap.bmp";   const char* pszDstFile = "H:\\GDAL文件\\gdal栅格矢量化\\shape.shp";   ImagePolygonize(pszSrcFile,pszDstFile,"ESRI Shapefile");  // system("pause");   return 0;}int ImagePolygonize(const char * pszSrcFile,const char* pszDstFile,const char* pszFormat){GDALAllRegister();OGRRegisterAll();//记得添加驱动注册CPLSetConfigOption("GDAL_FILENAME_IS_UTF8","NO");GDALDataset* poSrcDS=(GDALDataset*)GDALOpen(pszSrcFile,GA_ReadOnly);if(poSrcDS==NULL){return 0;}// 创建输出矢量文件OGRSFDriver *poDriver;poDriver = OGRSFDriverRegistrar::GetRegistrar()->GetDriverByName( pszFormat );if (poDriver == NULL){  GDALClose((GDALDatasetH)poSrcDS); return 0;}//根据文件名创建输出矢量文件OGRDataSource* poDstDS=poDriver->CreateDataSource(pszDstFile);if (poDstDS==NULL){GDALClose((GDALDatasetH)poSrcDS);return 0;}// 定义空间参考，与输入图像相同;OGRSpatialReference *poSpatialRef = new OGRSpatialReference(poSrcDS->GetProjectionRef());OGRLayer* poLayer = poDstDS->CreateLayer("Result", poSpatialRef, wkbPolygon, NULL);if (poDstDS == NULL) {GDALClose((GDALDatasetH)poSrcDS); OGRDataSource::DestroyDataSource(poDstDS); delete poSpatialRef; poSpatialRef = NULL; return 0;}OGRFieldDefn ofieldDef("Segment", OFTInteger); //创建属性表，只有一个字段即“Segment”，里面保存对应的栅格的像元值poLayer->CreateField(&ofieldDef);GDALRasterBandH hSrcBand = (GDALRasterBandH) poSrcDS->GetRasterBand(1); //获取图像的第一个波段GDALPolygonize(hSrcBand, NULL, (OGRLayerH)poLayer, 0, NULL, NULL, NULL); //调用栅格矢量化GDALClose(poSrcDS); //关闭文件OGRDataSource::DestroyDataSource(poDstDS);return 1;}

可以处理分类后的栅格图像，建议在做矢量化之前，对分类后的图像进行滤波，去除小碎斑块，不然这些小碎斑块会影响处理进度。