diff --git a/swh/scanner/scanner.py b/swh/scanner/scanner.py
--- a/swh/scanner/scanner.py
+++ b/swh/scanner/scanner.py
@@ -4,21 +4,23 @@
 # See top-level LICENSE file for more information
 
 import asyncio
-import fnmatch
-import glob
 import itertools
 import os
 from pathlib import Path
-import re
 from typing import Any, Dict, Iterable, Iterator, List, Pattern, Tuple, Union
 
 import aiohttp
 
-from swh.model.from_disk import Content, Directory, accept_all_directories
+from swh.model.from_disk import (
+    Content,
+    Directory,
+    accept_all_directories,
+    extract_regex_objs,
+)
 from swh.model.identifiers import CoreSWHID, ObjectType
 
 from .dashboard.dashboard import run_app
-from .exceptions import InvalidDirectoryPath, error_response
+from .exceptions import error_response
 from .model import Tree
 from .plot import generate_sunburst
 
@@ -68,7 +70,7 @@
 
 
 def directory_filter(
-    path_name: Union[str, bytes], exclude_patterns: Iterable[Pattern[str]]
+    path_name: Union[str, bytes], exclude_patterns: Iterable[Pattern[bytes]]
 ) -> bool:
     """It checks if the path_name is matching with the patterns given in input.
 
@@ -80,14 +82,15 @@
 
     """
     path = Path(path_name.decode() if isinstance(path_name, bytes) else path_name)
+
     for sre_pattern in exclude_patterns:
-        if sre_pattern.match(str(path)):
+        if sre_pattern.match(bytes(path)):
             return False
     return True
 
 
 def get_subpaths(
-    path: Path, exclude_patterns: Iterable[Pattern[str]]
+    path: Path, exclude_patterns: Iterable[Pattern[bytes]]
 ) -> Iterator[Tuple[Path, str]]:
     """Find the SoftWare Heritage persistent IDentifier (SWHID) of
     the directories and files under a given path.
@@ -104,7 +107,7 @@
         if path.is_dir():
             if exclude_patterns:
 
-                def dir_filter(dirpath: str, *args) -> bool:
+                def dir_filter(dirpath: bytes, *args) -> bool:
                     return directory_filter(dirpath, exclude_patterns)
 
             else:
@@ -131,7 +134,7 @@
     path: Path,
     session: aiohttp.ClientSession,
     api_url: str,
-    exclude_patterns: Iterable[Pattern[str]],
+    exclude_patterns: Iterable[Pattern[bytes]],
 ) -> Iterator[Tuple[str, str, bool]]:
     """Check if the sub paths of the given path are present in the
     archive or not.
@@ -161,7 +164,7 @@
     config: Dict[str, Any],
     root: str,
     source_tree: Tree,
-    exclude_patterns: Iterable[Pattern[str]],
+    exclude_patterns: Iterable[Pattern[bytes]],
 ) -> None:
     """Start scanning from the given root.
 
@@ -198,29 +201,6 @@
         await _scan(root, session, api_url, source_tree, exclude_patterns)
 
 
-def extract_regex_objs(
-    root_path: Path, patterns: Iterable[str]
-) -> Iterator[Pattern[str]]:
-    """Generates a regex object for each pattern given in input and checks if
-       the path is a subdirectory or relative to the root path.
-
-       Yields:
-          an SRE_Pattern object
-    """
-    for pattern in patterns:
-        for path in glob.glob(pattern):
-            dirpath = Path(path)
-            if root_path not in dirpath.parents:
-                error_msg = (
-                    f'The path "{dirpath}" is not a subdirectory or relative '
-                    f'to the root directory path: "{root_path}"'
-                )
-                raise InvalidDirectoryPath(error_msg)
-
-        regex = fnmatch.translate((pattern))
-        yield re.compile(regex)
-
-
 def scan(
     config: Dict[str, Any],
     root_path: str,
@@ -230,10 +210,12 @@
 ):
     """Scan a source code project to discover files and directories already
     present in the archive"""
+    converted_patterns = set(pattern.encode() for pattern in exclude_patterns)
     sre_patterns = set()
     if exclude_patterns:
         sre_patterns = {
-            reg_obj for reg_obj in extract_regex_objs(Path(root_path), exclude_patterns)
+            reg_obj
+            for reg_obj in extract_regex_objs(root_path.encode(), converted_patterns)
         }
 
     source_tree = Tree(Path(root_path))
diff --git a/swh/scanner/tests/test_scanner.py b/swh/scanner/tests/test_scanner.py
--- a/swh/scanner/tests/test_scanner.py
+++ b/swh/scanner/tests/test_scanner.py
@@ -8,7 +8,8 @@
 from flask import url_for
 import pytest
 
-from swh.scanner.exceptions import APIError, InvalidDirectoryPath
+from swh.model.exceptions import InvalidDirectoryPath
+from swh.scanner.exceptions import APIError
 from swh.scanner.model import Tree
 from swh.scanner.scanner import extract_regex_objs, get_subpaths, run, swhids_discovery
 
@@ -18,13 +19,14 @@
 
 
 def test_extract_regex_objs(temp_folder):
-    root_path = temp_folder["root"]
+    root_path = bytes(temp_folder["root"])
+
+    patterns = (bytes(temp_folder["subdir"]), b"/none")
 
-    patterns = (str(temp_folder["subdir"]), "/none")
     sre_patterns = [reg_obj for reg_obj in extract_regex_objs(root_path, patterns)]
     assert len(sre_patterns) == 2
 
-    patterns = (*patterns, "/tmp")
+    patterns = (*patterns, b"/tmp")
     with pytest.raises(InvalidDirectoryPath):
         sre_patterns = [reg_obj for reg_obj in extract_regex_objs(root_path, patterns)]
 
@@ -102,10 +104,11 @@
 ):
     api_url = url_for("index", _external=True)
     config = {"web-api": {"url": api_url, "auth-token": None}}
+    to_exclude_dir = str(test_sample_folder) + "/toexclude"
 
-    patterns = (str(test_sample_folder) + "/toexclude",)
+    patterns = (to_exclude_dir.encode(),)
     exclude_pattern = {
-        reg_obj for reg_obj in extract_regex_objs(test_sample_folder, patterns)
+        reg_obj for reg_obj in extract_regex_objs(bytes(test_sample_folder), patterns)
     }
 
     source_tree = Tree(test_sample_folder)