diff --git a/README.md b/README.md
index 9d0accc..9fa313e 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ Current supported features are:
 * streaming of various audio file formats
 * [transcoding]
 * user or random playlists
-* cover arts (`cover.jpg` files in the same folder as music files)
+* cover arts (as image files in the same folder as music files)
 * starred tracks/albums and ratings
 * [Last.FM][lastfm] scrobbling
 
diff --git a/schema/migration/20180521.mysql.sql b/schema/migration/20180521.mysql.sql
new file mode 100644
index 0000000..285c827
--- /dev/null
+++ b/schema/migration/20180521.mysql.sql
@@ -0,0 +1,12 @@
+START TRANSACTION;
+
+ALTER TABLE folder ADD cover_art VARCHAR(256) AFTER has_cover_art;
+
+UPDATE folder
+SET cover_art = 'cover.jpg'
+WHERE has_cover_art;
+
+ALTER TABLE folder DROP COLUMN has_cover_art;
+
+COMMIT;
+
diff --git a/schema/migration/20180521.postgresql.sql b/schema/migration/20180521.postgresql.sql
new file mode 100644
index 0000000..2c7da54
--- /dev/null
+++ b/schema/migration/20180521.postgresql.sql
@@ -0,0 +1,12 @@
+START TRANSACTION;
+
+ALTER TABLE folder ADD cover_art VARCHAR(256);
+
+UPDATE folder
+SET cover_art = 'cover.jpg'
+WHERE has_cover_art;
+
+ALTER TABLE folder DROP COLUMN has_cover_art;
+
+COMMIT;
+
diff --git a/schema/migration/20180521.sqlite.sql b/schema/migration/20180521.sqlite.sql
new file mode 100644
index 0000000..4ffbdc2
--- /dev/null
+++ b/schema/migration/20180521.sqlite.sql
@@ -0,0 +1,27 @@
+BEGIN TRANSACTION;
+
+DROP INDEX index_folder_path;
+ALTER TABLE folder RENAME TO folder_old;
+
+CREATE TABLE folder (
+    id CHAR(36) PRIMARY KEY,
+    root BOOLEAN NOT NULL,
+    name VARCHAR(256) NOT NULL COLLATE NOCASE,
+    path VARCHAR(4096) NOT NULL,
+    path_hash BLOB NOT NULL,
+    created DATETIME NOT NULL,
+    cover_art VARCHAR(256),
+    last_scan INTEGER NOT NULL,
+    parent_id CHAR(36) REFERENCES folder
+);
+CREATE UNIQUE INDEX index_folder_path ON folder(path_hash);
+
+INSERT INTO folder(id, root, name, path, path_hash, created, cover_art, last_scan, parent_id)
+SELECT id, root, name, path, path_hash, created, CASE WHEN has_cover_art THEN 'cover.jpg' ELSE NULL END, last_scan, parent_id
+FROM folder_old;
+
+DROP TABLE folder_old;
+
+COMMIT;
+VACUUM;
+
diff --git a/schema/mysql.sql b/schema/mysql.sql
index 518c9c0..edc54e2 100644
--- a/schema/mysql.sql
+++ b/schema/mysql.sql
@@ -5,7 +5,7 @@ CREATE TABLE folder (
     path VARCHAR(4096) NOT NULL,
     path_hash BINARY(20) NOT NULL,
     created DATETIME NOT NULL,
-    has_cover_art BOOLEAN NOT NULL,
+    cover_art VARCHAR(256),
     last_scan INTEGER NOT NULL,
     parent_id BINARY(16) REFERENCES folder
 ) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
diff --git a/schema/postgresql.sql b/schema/postgresql.sql
index e34a3e2..0c4f7a4 100644
--- a/schema/postgresql.sql
+++ b/schema/postgresql.sql
@@ -5,7 +5,7 @@ CREATE TABLE folder (
     path VARCHAR(4096) NOT NULL,
     path_hash BYTEA NOT NULL,
     created TIMESTAMP NOT NULL,
-    has_cover_art BOOLEAN NOT NULL,
+    cover_art VARCHAR(256),
     last_scan INTEGER NOT NULL,
     parent_id UUID REFERENCES folder
 );
diff --git a/schema/sqlite.sql b/schema/sqlite.sql
index ac076d3..5ee370d 100644
--- a/schema/sqlite.sql
+++ b/schema/sqlite.sql
@@ -5,7 +5,7 @@ CREATE TABLE folder (
     path VARCHAR(4096) NOT NULL,
     path_hash BLOB NOT NULL,
     created DATETIME NOT NULL,
-    has_cover_art BOOLEAN NOT NULL,
+    cover_art VARCHAR(256),
     last_scan INTEGER NOT NULL,
     parent_id CHAR(36) REFERENCES folder
 );
diff --git a/supysonic/api/media.py b/supysonic/api/media.py
index 9fe30fe..8ccf426 100644
--- a/supysonic/api/media.py
+++ b/supysonic/api/media.py
@@ -132,29 +132,30 @@ def download_media():
 @api.route('/getCoverArt.view', methods = [ 'GET', 'POST' ])
 def cover_art():
     res = get_entity(Folder)
-    if not res.has_cover_art or not os.path.isfile(os.path.join(res.path, 'cover.jpg')):
+    if not res.cover_art or not os.path.isfile(os.path.join(res.path, res.cover_art)):
         raise NotFound('Cover art')
 
+    cover_path = os.path.join(res.path, res.cover_art)
     size = request.values.get('size')
     if size:
         size = int(size)
     else:
-        return send_file(os.path.join(res.path, 'cover.jpg'))
+        return send_file(cover_path)
 
-    im = Image.open(os.path.join(res.path, 'cover.jpg'))
-    if size > im.size[0] and size > im.size[1]:
-        return send_file(os.path.join(res.path, 'cover.jpg'))
+    im = Image.open(cover_path)
+    if size > im.width and size > im.height:
+        return send_file(cover_path)
 
     size_path = os.path.join(current_app.config['WEBAPP']['cache_dir'], str(size))
     path = os.path.abspath(os.path.join(size_path, str(res.id)))
     if os.path.exists(path):
-        return send_file(path, mimetype = 'image/jpeg')
+        return send_file(path, mimetype = 'image/' + im.format.lower())
     if not os.path.exists(size_path):
         os.makedirs(size_path)
 
     im.thumbnail([size, size], Image.ANTIALIAS)
-    im.save(path, 'JPEG')
-    return send_file(path, mimetype = 'image/jpeg')
+    im.save(path, im.format)
+    return send_file(path, mimetype = 'image/' + im.format.lower())
 
 @api.route('/getLyrics.view', methods = [ 'GET', 'POST' ])
 def lyrics():
diff --git a/supysonic/covers.py b/supysonic/covers.py
new file mode 100644
index 0000000..c6fc1ab
--- /dev/null
+++ b/supysonic/covers.py
@@ -0,0 +1,80 @@
+# coding: utf-8
+#
+# This file is part of Supysonic.
+# Supysonic is a Python implementation of the Subsonic server API.
+#
+# Copyright (C) 2018 Alban 'spl0k' Féron
+#
+# Distributed under terms of the GNU AGPLv3 license.
+
+import os, os.path
+import re
+
+from PIL import Image
+
+EXTENSIONS = ('.jpg', '.jpeg', '.png', '.bmp')
+NAMING_SCORE_RULES = (
+    ('cover',    5),
+    ('albumart', 5),
+    ('folder',   5),
+    ('front',   10),
+    ('back',   -10),
+    ('large',    2),
+    ('small',   -2)
+)
+
+class CoverFile(object):
+    __clean_regex = re.compile(r'[^a-z]')
+    @staticmethod
+    def __clean_name(name):
+        return CoverFile.__clean_regex.sub('', name.lower())
+
+    def __init__(self, name, album_name = None):
+        self.name = name
+        self.score = 0
+
+        for part, score in NAMING_SCORE_RULES:
+            if part in name.lower():
+                self.score += score
+
+        if album_name:
+            basename, _ = os.path.splitext(name)
+            clean = CoverFile.__clean_name(basename)
+            album_name = CoverFile.__clean_name(album_name)
+            if clean in album_name or album_name in clean:
+                self.score += 20
+
+def is_valid_cover(path):
+    if not os.path.isfile(path):
+        return False
+
+    _, ext = os.path.splitext(path)
+    if ext.lower() not in EXTENSIONS:
+        return False
+
+    try: # Ensure the image can be read
+        with Image.open(path):
+            return True
+    except IOError:
+        return False
+
+def find_cover_in_folder(path, album_name = None):
+    if not os.path.isdir(path):
+        raise ValueError('Invalid path')
+
+    candidates = []
+    for f in os.listdir(path):
+        file_path = os.path.join(path, f)
+        if not is_valid_cover(file_path):
+            continue
+
+        cover = CoverFile(f, album_name)
+        candidates.append(cover)
+
+    if not candidates:
+        return None
+    if len(candidates) == 1:
+        return candidates[0]
+
+    return sorted(candidates, key = lambda c: c.score, reverse = True)[0]
+
diff --git a/supysonic/db.py b/supysonic/db.py
index 6b3c56f..179b2ff 100644
--- a/supysonic/db.py
+++ b/supysonic/db.py
@@ -59,7 +59,7 @@ class Folder(PathMixin, db.Entity):
     path = Required(str, 4096) # unique
     _path_hash = Required(buffer, column = 'path_hash')
     created = Required(datetime, precision = 0, default = now)
-    has_cover_art = Required(bool, default = False)
+    cover_art = Optional(str, nullable = True)
     last_scan = Required(int, default = 0)
 
     parent = Optional(lambda: Folder, reverse = 'children', column = 'parent_id')
@@ -82,7 +82,7 @@ class Folder(PathMixin, db.Entity):
         if not self.root:
             info['parent'] = str(self.parent.id)
             info['artist'] = self.parent.name
-        if self.has_cover_art:
+        if self.cover_art:
             info['coverArt'] = str(self.id)
 
         try:
@@ -163,7 +163,7 @@ class Album(db.Entity):
             created = min(self.tracks.created).isoformat()
         )
 
-        track_with_cover = self.tracks.select(lambda t: t.folder.has_cover_art).first()
+        track_with_cover = self.tracks.select(lambda t: t.folder.cover_art is not None).first()
         if track_with_cover is not None:
             info['coverArt'] = str(track_with_cover.folder.id)
 
@@ -242,7 +242,7 @@ class Track(PathMixin, db.Entity):
             info['year'] = self.year
         if self.genre:
             info['genre'] = self.genre
-        if self.folder.has_cover_art:
+        if self.folder.cover_art:
             info['coverArt'] = str(self.folder.id)
 
         try:
diff --git a/supysonic/scanner.py b/supysonic/scanner.py
index ac6fcff..3b8ebb2 100644
--- a/supysonic/scanner.py
+++ b/supysonic/scanner.py
@@ -14,6 +14,7 @@ import time
 
 from pony.orm import db_session
 
+from .covers import find_cover_in_folder
 from .db import Folder, Artist, Album, Track, User
 from .db import StarredFolder, StarredArtist, StarredAlbum, StarredTrack
 from .db import RatingFolder, RatingTrack
@@ -84,7 +85,15 @@ class Scanner:
         folders = [ folder ]
         while folders:
             f = folders.pop()
-            f.has_cover_art = os.path.isfile(os.path.join(f.path, 'cover.jpg'))
+
+            album_name = None
+            track = f.tracks.select().first()
+            if track is not None:
+                album_name = track.album.name
+
+            cover = find_cover_in_folder(f.path, album_name)
+            f.cover_art = cover.name if cover is not None else None
+
             folders += f.children
 
         folder.last_scan = int(time.time())
diff --git a/tests/api/test_media.py b/tests/api/test_media.py
index ec6b5bd..26b43f7 100644
--- a/tests/api/test_media.py
+++ b/tests/api/test_media.py
@@ -28,7 +28,7 @@ class MediaTestCase(ApiTestBase):
                 name = 'Root',
                 path = os.path.abspath('tests/assets'),
                 root = True,
-                has_cover_art = True # 420x420 PNG
+                cover_art = 'cover.jpg'
             )
             self.folderid = folder.id
 
diff --git a/tests/base/test_db.py b/tests/base/test_db.py
index 90361d9..8421f7f 100644
--- a/tests/base/test_db.py
+++ b/tests/base/test_db.py
@@ -42,7 +42,7 @@ class DbTestCase(unittest.TestCase):
             root = False,
             name = 'Child folder',
             path = 'tests/assets',
-            has_cover_art = True,
+            cover_art = 'cover.jpg',
             parent = root_folder
         )