diff --git a/src/io/gpr/IprbReader.cpp b/src/io/gpr/IprbReader.cpp
index a41541d..4441753 100644
--- a/src/io/gpr/IprbReader.cpp
+++ b/src/io/gpr/IprbReader.cpp
@@ -13,9 +13,9 @@ BScan readIprb(const std::string& path, const IprHeader& h) {
   }
 
   const std::streamsize fileSize = f.tellg();
-  const long traces = h.lastTrace + 1;
-  const long count = static_cast<long>(h.samples) * traces;
-  const std::streamsize expected = static_cast<std::streamsize>(count) * 2;
+  const std::int64_t traces = static_cast<std::int64_t>(h.lastTrace) + 1;
+  const std::int64_t count = static_cast<std::int64_t>(h.samples) * traces;
+  const std::int64_t expected = count * 2;
   if (fileSize != expected) {
     throw std::runtime_error("readIprb: 文件大小与 samples*traces*2 不符: " + path);
   }
@@ -23,10 +23,10 @@ BScan readIprb(const std::string& path, const IprHeader& h) {
   BScan b;
   b.samples = h.samples;
   b.traces = traces;
-  b.data.resize(static_cast<std::size_t>(count));
+  b.data.resize(static_cast<std::size_t>(h.samples) * traces);
 
   f.seekg(0, std::ios::beg);
-  f.read(reinterpret_cast<char*>(b.data.data()), expected);
+  f.read(reinterpret_cast<char*>(b.data.data()), static_cast<std::streamsize>(expected));
   if (!f) {
     throw std::runtime_error("readIprb: 读取数据失败: " + path);
   }
diff --git a/src/io/gpr/IprbReader.hpp b/src/io/gpr/IprbReader.hpp
index 90aa5b5..c6edc29 100644
--- a/src/io/gpr/IprbReader.hpp
+++ b/src/io/gpr/IprbReader.hpp
@@ -12,7 +12,7 @@ namespace geopro::io::gpr {
 // 一个通道一条测线的雷达 B-scan 剖面（int16 存储，布局 [trace*samples + s]，s 最快）。
 struct BScan {
   int samples = 0;
-  long traces = 0;
+  std::int64_t traces = 0;
   std::vector<int16_t> data;  // 大小 = samples*traces
 };