利用GDAL vrt实现单波段浮点数dem包装为三波段rgb影像

利用GDAL vrt实现单波段浮点数dem包装为三波段rgb影像

      本文介绍了利用GDAL vrt实现单波段浮点数dem包装为三波段rgb影像，具体为用vrt表达dem、将dem拉伸为0-255 区间的灰度图、灰度着色三个过程，所有中间结果可用vrt格式来表达。

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目录

• 1 dem vrt表达
• 2 dem灰度拉伸
• 3 dem着色

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• 1 dem vrt表达

{//vrt表达
		GDALAllRegister();
		std::string srcPath = "test.tif";
		std::string dstPath = "test.vrt";
		GDALDatasetH* srcDs = NULL;

		const char* arr[] = { srcPath.c_str() };
		const char* const* papszSrcDSNames = arr;
		GDALDatasetH hOutDs = GDALBuildVRT(dstPath.c_str(), 1, NULL, papszSrcDSNames, NULL, NULL);
		GDALClose(hOutDs);
	}

        借助GDALBuildVRT构建tif的vrt描述文件。

• 2 dem灰度拉伸

{//灰度拉伸
		std::string srcPath = "test.vrt";
		std::string dstPath = "gray.vrt";
		GDALAllRegister();
		GDALDataset* inDataset = (GDALDataset*)GDALOpen(srcPath.c_str(), GA_ReadOnly);
		GDALRasterBand*band = inDataset->GetRasterBand(1);
		/*double minValue, maxValue;
		band->ComputeStatistics(false, &minValue, &maxValue, NULL, NULL, NULL, NULL);
		band->SetNoDataValue(0);
		band->SetScale(256 / (maxValue - minValue));
		band->SetOffset(-minValue * 256 / (maxValue - minValue));*/