Files are now uniquely identified through a SHA1 hash, as opposed to

using the song name.

dejavu/__init__.py

@@ -36,12 +36,11 @@ class Dejavu(object):
 
     def get_fingerprinted_songs(self):
         # get songs previously indexed
-        # TODO: should probably use a checksum of the file instead of filename
         self.songs = self.db.get_songs()
-        self.songnames_set = set()  # to know which ones we've computed before
+        self.songhashes_set = set()  # to know which ones we've computed before
         for song in self.songs:
-            song_name = song[self.db.FIELD_SONGNAME]
+            song_hash = song[self.db.FIELD_SHA1]
-            self.songnames_set.add(song_name)
+            self.songhashes_set.add(song_hash)
 
     def fingerprint_directory(self, path, extensions, nprocesses=None):
         # Try to use the maximum amount of processes if not given.
@@ -58,7 +57,7 @@ class Dejavu(object):
         for filename, _ in decoder.find_files(path, extensions):
 
             # don't refingerprint already fingerprinted files
-            if decoder.path_to_songname(filename) in self.songnames_set:
+            if decoder.unique_hash(filename) in self.songhashes_set:
                 print "%s already fingerprinted, continuing..." % filename
                 continue
 
@@ -75,7 +74,7 @@ class Dejavu(object):
         # Loop till we have all of them
         while True:
             try:
-                song_name, hashes = iterator.next()
+                song_name, hashes, file_hash = iterator.next()
             except multiprocessing.TimeoutError:
                 continue
             except StopIteration:
@@ -85,7 +84,7 @@ class Dejavu(object):
                 # Print traceback because we can't reraise it here
                 traceback.print_exc(file=sys.stdout)
             else:
-                sid = self.db.insert_song(song_name)
+                sid = self.db.insert_song(song_name, file_hash)
 
                 self.db.insert_hashes(sid, hashes)
                 self.db.set_song_fingerprinted(sid)
@@ -96,16 +95,18 @@ class Dejavu(object):
 
     def fingerprint_file(self, filepath, song_name=None):
         songname = decoder.path_to_songname(filepath)
+        song_hash = decoder.unique_hash(filepath)
         song_name = song_name or songname
         # don't refingerprint already fingerprinted files
-        if song_name in self.songnames_set:
+        if song_hash in self.songhashes_set:
             print "%s already fingerprinted, continuing..." % song_name
         else:
-            song_name, hashes = _fingerprint_worker(filepath,
+            song_name, hashes, file_hash = _fingerprint_worker(
+                filepath,
                 self.limit,
-                                                    song_name=song_name)
+                song_name=song_name
-
+            )
-            sid = self.db.insert_song(song_name)
+            sid = self.db.insert_song(song_name, file_hash)
 
             self.db.insert_hashes(sid, hashes)
             self.db.set_song_fingerprinted(sid)
@@ -177,7 +178,7 @@ def _fingerprint_worker(filename, limit=None, song_name=None):
 
     songname, extension = os.path.splitext(os.path.basename(filename))
     song_name = song_name or songname
-    channels, Fs = decoder.read(filename, limit)
+    channels, Fs, file_hash = decoder.read(filename, limit)
     result = set()
     channel_amount = len(channels)
 
@@ -191,7 +192,7 @@ def _fingerprint_worker(filename, limit=None, song_name=None):
                                                  filename))
         result |= set(hashes)
 
-    return song_name, result
+    return song_name, result, file_hash
 
 
 def chunkify(lst, n):

dejavu/database_sql.py

@@ -54,6 +54,7 @@ class SQLDatabase(Database):
     FIELD_HASH = "hash"
     FIELD_SONG_ID = "song_id"
     FIELD_OFFSET = "offset"
+    FIELD_SHA1 = 'file_sha1'
     FIELD_SONGNAME = "song_name"
     FIELD_FINGERPRINTED = "fingerprinted"
 
@@ -78,10 +79,12 @@ class SQLDatabase(Database):
             `%s` mediumint unsigned not null auto_increment,
             `%s` varchar(250) not null,
             `%s` tinyint default 0,
+            `%s` binary(10) not null,
         PRIMARY KEY (`%s`),
         UNIQUE KEY `%s` (`%s`)
     ) ENGINE=INNODB;""" % (
         SONGS_TABLENAME, FIELD_SONG_ID, FIELD_SONGNAME, FIELD_FINGERPRINTED,
+        FIELD_SHA1,
         FIELD_SONG_ID, FIELD_SONG_ID, FIELD_SONG_ID,
     )
 
@@ -91,8 +94,8 @@ class SQLDatabase(Database):
             (UNHEX(%%s), %%s, %%s);
     """ % (FINGERPRINTS_TABLENAME, FIELD_HASH, FIELD_SONG_ID, FIELD_OFFSET)
 
-    INSERT_SONG = "INSERT INTO %s (%s) values (%%s);" % (
+    INSERT_SONG = "INSERT INTO %s (%s, %s) values (%%s, UNHEX(%%s));" % (
-        SONGS_TABLENAME, FIELD_SONGNAME)
+        SONGS_TABLENAME, FIELD_SONGNAME, FIELD_SHA1)
 
     # selects
     SELECT = """
@@ -109,8 +112,8 @@ class SQLDatabase(Database):
     """ % (FIELD_SONG_ID, FIELD_OFFSET, FINGERPRINTS_TABLENAME)
 
     SELECT_SONG = """
-        SELECT %s FROM %s WHERE %s = %%s
+        SELECT %s, HEX(%s) FROM %s WHERE %s = %%s
-    """ % (FIELD_SONGNAME, SONGS_TABLENAME, FIELD_SONG_ID)
+    """ % (FIELD_SONGNAME, FIELD_SHA1, SONGS_TABLENAME, FIELD_SONG_ID)
 
     SELECT_NUM_FINGERPRINTS = """
         SELECT COUNT(*) as n FROM %s
@@ -121,8 +124,9 @@ class SQLDatabase(Database):
     """ % (FIELD_SONG_ID, SONGS_TABLENAME, FIELD_FINGERPRINTED)
 
     SELECT_SONGS = """
-        SELECT %s, %s FROM %s WHERE %s = 1;
+        SELECT %s, %s, HEX(%s) FROM %s WHERE %s = 1;
-    """ % (FIELD_SONG_ID, FIELD_SONGNAME, SONGS_TABLENAME, FIELD_FINGERPRINTED)
+    """ % (FIELD_SONG_ID, FIELD_SONGNAME, FIELD_SHA1,
+           SONGS_TABLENAME, FIELD_FINGERPRINTED)
 
     # drops
     DROP_FINGERPRINTS = "DROP TABLE IF EXISTS %s;" % FINGERPRINTS_TABLENAME
@@ -235,12 +239,12 @@ class SQLDatabase(Database):
         with self.cursor() as cur:
             cur.execute(self.INSERT_FINGERPRINT, (hash, sid, offset))
 
-    def insert_song(self, songname):
+    def insert_song(self, songname, file_hash):
         """
         Inserts song in the database and returns the ID of the inserted record.
         """
         with self.cursor() as cur:
-            cur.execute(self.INSERT_SONG, (songname,))
+            cur.execute(self.INSERT_SONG, (songname, file_hash))
             return cur.lastrowid
 
     def query(self, hash):

dejavu/decoder.py

@@ -4,6 +4,20 @@ import numpy as np
 from pydub import AudioSegment
 from pydub.utils import audioop
 import wavio
+from hashlib import sha1
+
+def unique_hash(filepath):
+    """ Small function to generate a hash to uniquely generate
+    a file. Taken / inspired from git's way via stackoverflow:
+    http://stackoverflow.com/questions/552659
+    """
+    filesize_bytes = os.path.getsize(filepath)
+    s = sha1()
+    s.update(("blob %u\0" % filesize_bytes).encode('ascii'))
+    with open(filepath, 'rb') as f:
+        s.update(f.read())
+    return s.hexdigest()
+
 
 def find_files(path, extensions):
     # Allow both with ".mp3" and without "mp3" to be used for extensions
@@ -55,7 +69,7 @@ def read(filename, limit=None):
         for chn in audiofile:
             channels.append(chn)
 
-    return channels, fs
+    return channels, audiofile.frame_rate, unique_hash(filename)
 
 
 def path_to_songname(path):

dejavu/recognize.py

@@ -26,7 +26,7 @@ class FileRecognizer(BaseRecognizer):
         super(FileRecognizer, self).__init__(dejavu)
 
     def recognize_file(self, filename):
-        frames, self.Fs = decoder.read(filename, self.dejavu.limit)
+        frames, self.Fs, file_hash = decoder.read(filename, self.dejavu.limit)
 
         t = time.time()
         match = self._recognize(*frames)