diff --git a/schemsearch-lib/src/compare.c b/schemsearch-lib/src/compare.c
index b74dd75..2bb64be 100644
--- a/schemsearch-lib/src/compare.c
+++ b/schemsearch-lib/src/compare.c
@@ -37,27 +37,27 @@ int32_t isMatching(
 void is_matching_all(
         const int32_t *schem_data,
         const int32_t *pattern_data,
-        size_t schem_width,
-        size_t schem_height,
-        size_t schem_length,
-        size_t pattern_width,
-        size_t pattern_height,
-        size_t pattern_length,
+        int32_t schem_width,
+        int32_t schem_height,
+        int32_t schem_length,
+        int32_t pattern_width,
+        int32_t pattern_height,
+        int32_t pattern_length,
         int32_t *result
 ) {
-    for (size_t pz = 0; pz < pattern_length; ++pz) {
-        size_t maxZ = schem_length - pattern_length + pz + 1;
-        for (size_t py = 0; py < pattern_height; ++py) {
-            size_t maxY = schem_height - pattern_height + py + 1;
-            for (size_t px = 0; px < pattern_width; ++px) {
+    for (int32_t pz = 0; pz < pattern_length; ++pz) {
+        int32_t maxZ = schem_length - pattern_length + pz + 1;
+        for (int32_t py = 0; py < pattern_height; ++py) {
+            int32_t maxY = schem_height - pattern_height + py + 1;
+            for (int32_t px = 0; px < pattern_width; ++px) {
                 int32_t pv = pattern_data[px + py * pattern_width + pz * pattern_width * pattern_height];
-                size_t maxX = schem_width - pattern_width + px + 1;
-                for (size_t z = pz; z < maxZ; ++z) {
-                    size_t sourceOffsetZ = z * schem_width * schem_height;
-                    size_t resultOffsetZ = (z - pz) * schem_width * schem_height - py * schem_width;
-                    for (size_t y = py; y < maxY; ++y) {
-                        size_t sourceOffsetY = sourceOffsetZ + y * schem_width;
-                        size_t resultOffsetY = resultOffsetZ + y * schem_width - px;
+                int32_t maxX = schem_width - pattern_width + px + 1;
+                for (int32_t z = pz; z < maxZ; ++z) {
+                    int32_t sourceOffsetZ = z * schem_width * schem_height;
+                    int32_t resultOffsetZ = (z - pz) * schem_width * schem_height - py * schem_width;
+                    for (int32_t y = py; y < maxY; ++y) {
+                        int32_t sourceOffsetY = sourceOffsetZ + y * schem_width;
+                        int32_t resultOffsetY = resultOffsetZ + y * schem_width - px;
                         for (size_t x = px; x < maxX; ++x) {
                             result[resultOffsetY + x] += schem_data[sourceOffsetY + x] == pv;
                         }
diff --git a/schemsearch-lib/src/lib.rs b/schemsearch-lib/src/lib.rs
index 5dfb43c..ee31ade 100644
--- a/schemsearch-lib/src/lib.rs
+++ b/schemsearch-lib/src/lib.rs
@@ -53,12 +53,12 @@ extern "C" {
     pub fn is_matching_all(
         schem_data: *const i32,
         pattern_data: *const i32,
-        schem_width: usize,
-        schem_height: usize,
-        schem_length: usize,
-        pattern_width: usize,
-        pattern_height: usize,
-        pattern_length: usize,
+        schem_width: i32,
+        schem_height: i32,
+        schem_length: i32,
+        pattern_width: i32,
+        pattern_height: i32,
+        pattern_length: i32,
         result: *mut i32
     );
 }
@@ -149,12 +149,12 @@ pub fn search(
         is_matching_all(
             schem_data,
             pattern_data,
-            schem_width,
-            schem_height,
-            schem_length,
-            pattern_width,
-            pattern_height,
-            pattern_length,
+            schem_width as i32,
+            schem_height as i32,
+            schem_length as i32,
+            pattern_width as i32,
+            pattern_height as i32,
+            pattern_length as i32,
             result.as_mut_ptr()
         );
     }