gdal对tif图像分块投影转换c++

你可以使用GDAL库来实现tif图像的分块投影转换。下面是一个简单的C++示例代码：

#include "gdal_priv.h"
#include "cpl_conv.h" // for CPLMalloc()

int main()
{
    // 输入文件名和输出文件名
    const char* inputFile = "input.tif";
    const char* outputFile = "output.tif";

    // 打开输入文件
    GDALDataset* poDataset = (GDALDataset*) GDALOpen(inputFile, GA_ReadOnly);
    if (poDataset == NULL)
    {
        printf("Failed to open file %s\n", inputFile);
        return 1;
    }

    // 获取输入文件的投影和地理信息
    double adfGeoTransform[6];
    poDataset->GetGeoTransform(adfGeoTransform);
    const char* pszProjection = poDataset->GetProjectionRef();

    // 获取输入文件的宽度和高度
    int width = poDataset->GetRasterXSize();
    int height = poDataset->GetRasterYSize();

    // 定义块大小
    int blockWidth = 256;
    int blockHeight = 256;

    // 创建输出文件
    GDALDriver* poDriver = GetGDALDriverManager()->GetDriverByName("GTiff");
    GDALDataset* poOutputDataset = poDriver->Create(outputFile, width, height, 1, GDT_Byte, NULL);
    poOutputDataset->SetGeoTransform(adfGeoTransform);
    poOutputDataset->SetProjection(pszProjection);

    // 分块处理
    for (int y = 0; y < height; y += blockHeight)
    {
        int blockYSize = MIN(blockHeight, height - y);
        for (int x = 0; x < width; x += blockWidth)
        {
            int blockXSize = MIN(blockWidth, width - x);

            // 读取输入块
            GByte* data = (GByte*) CPLMalloc(blockXSize * blockYSize);
            poDataset->RasterIO(GF_Read, x, y, blockXSize, blockYSize, data, blockXSize, blockYSize, GDT_Byte, 1, NULL, 0, 0, 0);

            // 投影转换
            double adfDstGeoTransform[6];
            adfDstGeoTransform[0] = adfGeoTransform[0] + x * adfGeoTransform[1] + y * adfGeoTransform[2];
            adfDstGeoTransform[1] = adfGeoTransform[1];
            adfDstGeoTransform[2] = adfGeoTransform[2];
            adfDstGeoTransform[3] = adfGeoTransform[3] + x * adfGeoTransform[4] + y * adfGeoTransform[5];
            adfDstGeoTransform[4] = adfGeoTransform[4];
            adfDstGeoTransform[5] = adfGeoTransform[5];
            GDALDataset* poMemDataset = poDriver->Create("", blockXSize, blockYSize, 1, GDT_Byte, NULL);
            poMemDataset->SetGeoTransform(adfDstGeoTransform);
            poMemDataset->SetProjection(pszProjection);
            poMemDataset->RasterIO(GF_Write, 0, 0, blockXSize, blockYSize, data, blockXSize, blockYSize, GDT_Byte, 1, NULL, 0, 0, 0);

            // 写入输出块
            poOutputDataset->RasterIO(GF_Write, x, y, blockXSize, blockYSize, data, blockXSize, blockYSize, GDT_Byte, 1, NULL, 0, 0, 0);

            // 释放内存
            CPLFree(data);
            GDALClose(poMemDataset);
        }
    }

    // 释放内存
    GDALClose(poDataset);
    GDALClose(poOutputDataset);

    return 0;
}

这个示例代码假设输入文件是一个灰度图像，输出文件也是一个灰度图像。如果输入文件是一个多波段图像，你需要修改代码来处理多波段数据。