[rhythmbox] artdisplay: add embedded cover art search

[Jonathan Matthew <jmatthew src gnome org>]

commit dce0829835741b0562ed09726473892bca41a05c
Author: Jonathan Matthew <jonathan d14n org>
Date:   Sat Apr 18 02:15:23 2009 +1000

    artdisplay: add embedded cover art search
    
    This uses a GStreamer pipeline to read embedded images.  Since the
    player will already read images for the playing entry, it only runs for
    entries that are not playing.  It only operates on local files.
    
    Fixes the rest of #345975.
---
 plugins/artdisplay/artdisplay/CoverArtDatabase.py  |    3 +-
 .../artdisplay/EmbeddedCoverArtSearch.py           |  131 ++++++++++++++++++++
 plugins/artdisplay/artdisplay/Makefile.am          |    1 +
 3 files changed, 134 insertions(+), 1 deletions(-)

diff --git a/plugins/artdisplay/artdisplay/CoverArtDatabase.py b/plugins/artdisplay/artdisplay/CoverArtDatabase.py
index 3931698..a0d0f6e 100644
--- a/plugins/artdisplay/artdisplay/CoverArtDatabase.py
+++ b/plugins/artdisplay/artdisplay/CoverArtDatabase.py
@@ -33,6 +33,7 @@ import gobject
 
 from PodcastCoverArtSearch import PodcastCoverArtSearch
 from AmazonCoverArtSearch import AmazonCoverArtSearch
+from EmbeddedCoverArtSearch import EmbeddedCoverArtSearch
 
 from urllib import unquote
 
@@ -45,7 +46,7 @@ try:
 except:
 	from LocalCoverArtSearch import LocalCoverArtSearch
 
-ART_SEARCHES_LOCAL = [LocalCoverArtSearch]
+ART_SEARCHES_LOCAL = [LocalCoverArtSearch, EmbeddedCoverArtSearch]
 ART_SEARCHES_REMOTE = [PodcastCoverArtSearch, AmazonCoverArtSearch]
 OLD_ART_FOLDER = '~/.gnome2/rhythmbox/covers'
 
diff --git a/plugins/artdisplay/artdisplay/EmbeddedCoverArtSearch.py b/plugins/artdisplay/artdisplay/EmbeddedCoverArtSearch.py
new file mode 100644
index 0000000..390f6e0
--- /dev/null
+++ b/plugins/artdisplay/artdisplay/EmbeddedCoverArtSearch.py
@@ -0,0 +1,131 @@
+# -*- Mode: python; coding: utf-8; tab-width: 8; indent-tabs-mode: t; -*-
+#
+# Copyright (C) 2009  Jonathan Matthew  <jonathan d14n org>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# The Rhythmbox authors hereby grant permission for non-GPL compatible
+# GStreamer plugins to be used and distributed together with GStreamer
+# and Rhythmbox. This permission is above and beyond the permissions granted
+# by the GPL license by which Rhythmbox is covered. If you modify this code
+# you may extend this exception to your version of the code, but you are not
+# obligated to do so. If you do not wish to do so, delete this exception
+# statement from your version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA.
+
+import rhythmdb
+
+import gst
+import gobject
+import gtk
+
+class EmbeddedCoverArtSearch (object):
+	def __init__ (self):
+		pass
+
+	def _tag_cb (self, bus, message):
+		taglist = message.parse_tag()
+		for tag in (gst.TAG_IMAGE, gst.TAG_PREVIEW_IMAGE):
+			if tag not in taglist.keys():
+				continue
+
+			print "got image tag %s" % tag
+			try:
+				loader = gtk.gdk.PixbufLoader()
+				if loader.write(taglist[tag]) and loader.close():
+					print "successfully extracted pixbuf"
+					self.got_pixbuf = True
+					self.callback(self, self.entry, loader.get_pixbuf(), *self.args)
+					return
+			except gobject.GError:
+				continue
+
+	def _state_changed_cb (self, bus, message):
+		if message.src != self.pipeline:
+			return
+
+		old, new, pending = message.parse_state_changed()
+		if ((new, pending) == (gst.STATE_PAUSED, gst.STATE_VOID_PENDING)):
+			print "pipeline has gone to PAUSED"
+			self.pipeline.set_state(gst.STATE_NULL)
+			if self.got_pixbuf is False:
+				self.callback(self, self.entry, None, *self.args)
+
+	def _error_cb (self, bus, message):
+		error = message.parse_error()
+		print "got error: %s" % error[1]
+		self.pipeline.set_state(gst.STATE_NULL)
+		self.callback(self, self.entry, None, *self.args)
+
+	def _decoded_pad_cb (self, decodebin, pad, last):
+		if self.sinkpad.is_linked():
+			return
+
+		caps = pad.get_caps()
+		if caps[0].get_name() in ('audio/x-raw-float', 'audio/x-raw-int'):
+			print "linking decoded audio pad to fakesink"
+			pad.link(self.sinkpad)
+
+	def search (self, db, entry, is_playing, on_search_completed, *args):
+
+		# only search if we're not already playing this entry
+		if is_playing:
+			print "not checking for embedded cover art in playing entry"
+			on_search_completed (self, entry, None, *args)
+			return
+
+		# only search local files
+		uri = db.entry_get(entry, rhythmdb.PROP_LOCATION)
+		if uri.startswith("file://") is False:
+			print "not checking for embedded cover art in non-local entry %s" % uri
+			on_search_completed (self, entry, None, *args)
+			return
+
+		self.entry = entry
+		self.args = args
+		self.callback = on_search_completed
+		self.args = args
+		self.got_pixbuf = False
+
+		# set up pipeline and bus callbacks
+		self.pipeline = gst.Pipeline()
+		bus = self.pipeline.get_bus()
+		bus.add_signal_watch()
+		bus.connect("message::tag", self._tag_cb)
+		bus.connect("message::state-changed", self._state_changed_cb)
+		bus.connect("message::error", self._error_cb)
+
+		# create elements
+		self.src = gst.element_make_from_uri(gst.URI_SRC, uri)
+		self.decodebin = gst.element_factory_make("decodebin2")
+		self.sink = gst.element_factory_make("fakesink")
+		self.decodebin.connect('new-decoded-pad', self._decoded_pad_cb)
+
+		self.pipeline.add(self.src, self.decodebin, self.sink)
+		self.src.link(self.decodebin)
+
+		self.sinkpad = self.sink.get_pad('sink')
+
+		self.pipeline.set_state(gst.STATE_PAUSED)
+
+
+	def search_next (self):
+		return False
+
+	def get_result_pixbuf (self, search_results):
+		return search_results
+
+	def get_best_match_urls (self, search_results):
+		return []
+
diff --git a/plugins/artdisplay/artdisplay/Makefile.am b/plugins/artdisplay/artdisplay/Makefile.am
index c13aa88..2cfe899 100644
--- a/plugins/artdisplay/artdisplay/Makefile.am
+++ b/plugins/artdisplay/artdisplay/Makefile.am
@@ -2,6 +2,7 @@
 
 plugindir = $(PLUGINDIR)/artdisplay
 plugin_PYTHON = 			\
+	EmbeddedCoverArtSearch.py	\
 	PodcastCoverArtSearch.py	\
 	AmazonCoverArtSearch.py		\
 	LocalCoverArtSearch.py		\