Use md5 hashes to make sure every images is only saved once

make_and_add_image will use already existing images from Tagger.images
if the hash of the image is the same as that of an image in there.

picard/coverart.py

@@ -101,8 +101,15 @@ def _coverart_downloaded(album, metadata, release, try_list, coverinfos, data, h
         filename = None
         if not is_front_image(coverinfos) and config.setting["caa_image_type_as_filename"]:
             filename = coverinfos['type']
+
         try:
-            image = Image(data, mime, coverinfos['type'], coverinfos['desc'])
+            metadata.make_and_add_image(mime, data,
+                                        imagetype=coverinfos['type'],
+                                        comment=coverinfos['desc'])
+            for track in album._new_tracks:
+                track.metadata.make_and_add_image(mime, data,
+                                                  imagetype=coverinfos['type'],
+                                                  comment=coverinfos['desc'])
         except (IOError, OSError), e:
             album.error_append(e.message)
             album._finalize_loading(error=True)
@@ -110,10 +117,6 @@ def _coverart_downloaded(album, metadata, release, try_list, coverinfos, data, h
             # save them in the temporary folder, abort.
             return
 
-        metadata.add_image(image)
-        for track in album._new_tracks:
-            track.metadata.add_image(image)
-
     # If the image already was a front image, there might still be some
     # other front images in the try_list - remove them.
     if is_front_image(coverinfos):

picard/metadata.py

@@ -21,9 +21,11 @@ import os.path
 import shutil
 import sys
 import tempfile
+import traceback
 
 
-from os import fdopen, close, unlink
+from hashlib import md5
+from os import fdopen, unlink
 from PyQt4.QtCore import QObject
 from picard import config, log
 from picard.plugin import ExtensionPoint
@@ -171,15 +173,11 @@ class Metadata(dict):
         self.images = []
         self.length = 0
 
-    def add_image(self, image):
-        """Adds the Image object ``image`` to this Metadata object.
-        """
-        self.images.append(image)
-
     def make_and_add_image(self, mime, data, filename=None, comment="",
-                            imagetype="front"):
+                           imagetype="front"):
         """Build a new image object from ``data`` and adds it to this Metadata
-        object.
+        object. If an image with the same MD5 hash has already been added to
+        any Metadata object, that file will be reused.
 
         Arguments:
         mime -- The mimetype of the image
@@ -188,7 +186,13 @@ class Metadata(dict):
         comment -- image description or comment, default to ''
         imagetype -- main type as a string, default to 'front'
         """
-        image = Image(data, mime, imagetype, comment)
+        m = md5()
+        m.update(data)
+        datahash = m.hexdigest()
+        image = QObject.tagger.images[datahash]
+        if image is None:
+            image = Image(data, mime, imagetype, comment)
+        QObject.tagger.images[datahash] = image
         self.images.append(image)
 
     def remove_image(self, index):

picard/tagger.py

@@ -31,6 +31,7 @@ import re
 import shutil
 import signal
 import sys
+from collections import defaultdict
 from functools import partial
 from itertools import chain
 
@@ -165,6 +166,7 @@ class Tagger(QtGui.QApplication):
         self.albums = {}
         self.release_groups = {}
         self.mbid_redirects = {}
+        self.images = defaultdict(lambda: None)
         self.unmatched_files = UnmatchedFiles()
         self.nats = None
         self.window = MainWindow()

picard/ui/infodialog.py

@@ -18,7 +18,9 @@
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
 import os.path
+import traceback
 from PyQt4 import QtGui, QtCore
+from picard import log
 from picard.util import format_time, encode_filename, bytes2human
 from picard.ui.ui_infodialog import Ui_InfoDialog
 
@@ -47,7 +49,11 @@ class InfoDialog(QtGui.QDialog):
             return
 
         for image in images:
-            data = image.data
+            try:
+                data = image.data
+            except (OSError, IOError), e:
+                log.error(traceback.format_exc())
+                continue
             size = len(data)
             item = QtGui.QListWidgetItem()
             pixmap = QtGui.QPixmap()