diff --git a/README.md b/README.md
index 824af5b..1f9155d 100644
--- a/README.md
+++ b/README.md
@@ -28,4 +28,4 @@ The installation in Windows can be done, though it is quite elaborate:
 * `cd .\dnn\face_detector`
 * `python.exe .\download_weights.py`
 * `cd .\visualhaar`
-* `cargo build --lib`
+* `cargo build --lib --release`
diff --git a/face_recognition/comparison.py b/face_recognition/comparison.py
index c82df69..6dbaeec 100644
--- a/face_recognition/comparison.py
+++ b/face_recognition/comparison.py
@@ -344,12 +344,12 @@ def process3_haar(in_q, out_q, cascade_file):
 
         typedef void* haarclassifier;
         haarclassifier classifier_new(char *filename);
-        void scan_image(haarclassifier, size_t width,size_t height, char *input, char *buffer, size_t length, bool debug);
+        void scan_image(haarclassifier, size_t width,size_t height, char *input, char *buffer, size_t length, size_t min_face_factor, bool debug);
     """)
 
     dir_path = os.path.dirname(os.path.realpath(__file__))
 
-    lib_path = os.path.join(dir_path, "..", "visualhaar", "target", "debug")
+    lib_path = os.path.join(dir_path, "..", "visualhaar", "target", "release")
     so_path = os.path.join(lib_path, "libvisual_haarcascades_lib.so")
     dll_path = os.path.join(lib_path, "visual_haarcascades_lib.dll")
 
@@ -404,7 +404,7 @@ def process3_haar(in_q, out_q, cascade_file):
         logger.info("Start haar scan")
 
         start = time.time()
-        C.scan_image(haar, width, height, buffer2, buffer, buffer_len, False)
+        C.scan_image(haar, width, height, buffer2, buffer, buffer_len, 5, False)
         logger.info(f"Visualised scan into buffer: {buffer}")
         print(f"duration: {time.time() - start}s")
 
diff --git a/visualhaar b/visualhaar
index 7c7ae29..ac1aea1 160000
--- a/visualhaar
+++ b/visualhaar
@@ -1 +1 @@
-Subproject commit 7c7ae29bf9e1390ea304e3708e8f92f6d57f87ff
+Subproject commit ac1aea1d68f346be194e64a3275629a177327f2e