diff --git a/src/tiff_max.cpp b/src/tiff_max.cpp
new file mode 100644
index 0000000..4c41e37
--- /dev/null
+++ b/src/tiff_max.cpp
@@ -0,0 +1,65 @@
+#include "gdal_priv.h"
+#include "cpl_conv.h" // for CPLMalloc()
+#include <iostream>
+#include <ctime>
+
+int main()
+{
+    const char *filename = "imgs/ortho.tif";
+
+    // 初始化 GDAL
+    GDALAllRegister();
+
+    clock_t start = clock();
+
+    // 打开数据集
+    GDALDataset *poDataset = (GDALDataset *)GDALOpen(filename, GA_ReadOnly);
+    if (poDataset == nullptr)
+    {
+        std::cerr << "Failed to open file: " << filename << std::endl;
+        return 1;
+    }
+
+    // 获取第一个波段
+    GDALRasterBand *poBand = poDataset->GetRasterBand(1);
+    if (!poBand)
+    {
+        std::cerr << "Failed to get raster band." << std::endl;
+        GDALClose(poDataset);
+        return 1;
+    }
+
+    int nX = poBand->GetXSize();
+    int nY = poBand->GetYSize();
+
+    // 分配缓冲区
+    uint8_t *buffer = (uint8_t *)CPLMalloc(sizeof(uint8_t) * nX * nY);
+
+    // 读取整个波段数据到内存中
+    CPLErr err = poBand->RasterIO(GF_Read, 0, 0, nX, nY, buffer, nX, nY, GDT_Byte, 0, 0);
+    if (err != CE_None)
+    {
+        std::cerr << "RasterIO failed." << std::endl;
+        CPLFree(buffer);
+        GDALClose(poDataset);
+        return 1;
+    }
+
+    // 查找最大值
+    uint8_t maxVal = 0;
+    for (int i = 0; i < nX * nY; i++)
+    {
+        if (buffer[i] > maxVal)
+            maxVal = buffer[i];
+    }
+
+    clock_t end = clock();
+
+    std::cout << "GDAL Max: " << (int)maxVal << std::endl;
+    std::cout << "Time taken: " << ((double)(end - start)) / CLOCKS_PER_SEC << " seconds" << std::endl;
+
+    CPLFree(buffer);
+    GDALClose(poDataset);
+
+    return 0;
+}