diff --git a/swh/journal/replay.py b/swh/journal/replay.py
--- a/swh/journal/replay.py
+++ b/swh/journal/replay.py
@@ -21,7 +21,75 @@
         _insert_objects(object_type, objects, storage)
 
 
+def _fix_revisions(revisions):
+    for rev in revisions:
+        # PyPI loader failed to encode empty strings as bytes, see:
+        # swh:1:rev:8f0095ee0664867055d03de9bcc8f95b91d8a2b9
+        # or https://forge.softwareheritage.org/D1772
+        if rev['author'].get('email') == '':
+            rev['author']['email'] = b''
+        if rev['author'].get('name') == '':
+            rev['author']['name'] = b''
+        if rev['committer'].get('email') == '':
+            rev['committer']['email'] = b''
+        if rev['committer'].get('name') == '':
+            rev['committer']['name'] = b''
+
+
+def _fix_origin_visits(visits):
+    for visit in visits:
+        if isinstance(visit['origin'], str):
+            # note that it will crash with the pg and
+            # in-mem storages if the origin is not already known,
+            # but there is no other choice because we can't add an
+            # origin without knowing its type. Non-pg storages
+            # don't use a numeric FK internally,
+            visit['origin'] = {'url': visit['origin']}
+        else:
+            if 'type' not in visit:
+                visit['type'] = visit['origin']['type']
+
+
+def fix_objects(object_type, objects):
+    """Converts a possibly old object from the journal to its current
+    expected format.
+
+    List of conversions:
+
+    Empty author name/email in PyPI releases:
+
+    >>> from pprint import pprint
+    >>> pprint(fix_objects('revision', [{
+    ...     'author': {'email': '', 'fullname': b'', 'name': ''},
+    ...     'committer': {'email': '', 'fullname': b'', 'name': ''},
+    ... }]))
+    [{'author': {'email': b'', 'fullname': b'', 'name': b''},
+      'committer': {'email': b'', 'fullname': b'', 'name': b''}}]
+
+
+    `visit['origin']` is an URL instead of a dict:
+
+    >>> fix_objects('origin_visit', [{'origin': 'http://foo'}])
+    [{'origin': {'url': 'http://foo'}}]
+
+    `visit['type']` is missing , but `origin['visit']['type']` exists:
+
+    >>> pprint(fix_objects(
+    ...     'origin_visit',
+    ...     [{'origin': {'type': 'hg', 'url': 'http://foo'}}]))
+    [{'origin': {'type': 'hg', 'url': 'http://foo'}, 'type': 'hg'}]
+    """
+
+    if object_type == 'revision':
+        _fix_revisions(objects)
+    elif object_type == 'origin_visit':
+        _fix_origin_visits(objects)
+    return objects
+
+
 def _insert_objects(object_type, objects, storage):
+    fix_objects(object_type, objects)
+
     if object_type == 'content':
         # TODO: insert 'content' in batches
         for object_ in objects:
@@ -37,19 +105,8 @@
         method(objects)
     elif object_type == 'origin_visit':
         for visit in objects:
-            if isinstance(visit['origin'], str):
-                # old format; note that it will crash with the pg and
-                # in-mem storages if the origin is not already known,
-                # but there is no other choice because we can't add an
-                # origin without knowing its type. Non-pg storages
-                # don't use a numeric FK internally,
-                visit['origin'] = {'url': visit['origin']}
-            else:
+            if 'type' in visit['origin']:
                 storage.origin_add_one(visit['origin'])
-                if 'type' not in visit:
-                    # old format
-                    visit['type'] = visit['origin']['type']
-
         storage.origin_visit_upsert(objects)
     else:
         logger.warning('Received a series of %s, this should not happen',