diff --git a/benchmark/benchmark.cpp b/benchmark/benchmark.cpp
index ed9a5a7..b51a9ab 100644
--- a/benchmark/benchmark.cpp
+++ b/benchmark/benchmark.cpp
@@ -14,16 +14,16 @@
 #include <dabnn/net.h>
 
 static void BM_pack_mat_64(benchmark::State &state) {
-    const bnn::Mat a(1, 64, 64, 128, bnn::DataType::Float, 0);
-    bnn::Mat b(1, 64, 64, 128, bnn::DataType::Bit, 0);
+    const bnn::Mat a(1, 64, 64, 128, bnn::DataType::Float);
+    bnn::Mat b(1, 64, 64, 128, bnn::DataType::Bit);
     for (auto _ : state) {
         pack_mat_64(a, b);
     }
 }
 
 static void BM_pack_mat_128(benchmark::State &state) {
-    const bnn::Mat a(1, 64, 64, 128, bnn::DataType::Float, 0);
-    bnn::Mat b(1, 64, 64, 128, bnn::DataType::Bit, 0);
+    const bnn::Mat a(1, 64, 64, 128, bnn::DataType::Float);
+    bnn::Mat b(1, 64, 64, 128, bnn::DataType::Bit);
     for (auto _ : state) {
         pack_mat_128(a, b);
     }
diff --git a/dabnn/mat.h b/dabnn/mat.h
index 0d0a8dc..ea98f9d 100644
--- a/dabnn/mat.h
+++ b/dabnn/mat.h
@@ -254,7 +254,7 @@ inline Mat::Mat(int _n, int _w, int _h, int _c, void *_data, DataType data_type,
     if (require_align) {
         hstep = ncnn::alignSize(w * c * elemsize, 16) / elemsize;
     } else {
-        hstep = w * c * elemsize;
+        hstep = w * c;
     }
     BNN_ASSERT(hstep > 0, hstep);
 
@@ -523,7 +523,7 @@ inline void Mat::create(int _n, int _w, int _h, int _c, DataType _data_type,
     if (require_align) {
         hstep = ncnn::alignSize(w * c * elemsize, 16) / elemsize;
     } else {
-        hstep = w * c * elemsize;
+        hstep = w * c;
     }
     BNN_ASSERT(hstep > 0, hstep);