diff --git a/src/calibre/db/backend.py b/src/calibre/db/backend.py
index 159612e52d..ba683dde50 100644
--- a/src/calibre/db/backend.py
+++ b/src/calibre/db/backend.py
@@ -222,7 +222,9 @@ class DB(object, SchemaUpgrade):
         if self.user_version == 0:
             self.initialize_database()
 
-        SchemaUpgrade.__init__(self)
+        with self.conn:
+            SchemaUpgrade.__init__(self)
+
         # Guarantee that the library_id is set
         self.library_id
 
diff --git a/src/calibre/db/errors.py b/src/calibre/db/errors.py
new file mode 100644
index 0000000000..d2657f9904
--- /dev/null
+++ b/src/calibre/db/errors.py
@@ -0,0 +1,13 @@
+#!/usr/bin/env python
+# vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import (unicode_literals, division, absolute_import,
+                        print_function)
+
+__license__   = 'GPL v3'
+__copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
+__docformat__ = 'restructuredtext en'
+
+
+class NoSuchFormat(ValueError):
+    pass
+
diff --git a/src/calibre/devices/apple/driver.py b/src/calibre/devices/apple/driver.py
index dea5844028..cc531b7476 100644
--- a/src/calibre/devices/apple/driver.py
+++ b/src/calibre/devices/apple/driver.py
@@ -107,6 +107,7 @@ class DriverBase(DeviceConfig, DevicePlugin):
     # Needed for config_widget to work
     FORMATS = ['epub', 'pdf']
     USER_CAN_ADD_NEW_FORMATS = False
+    KEEP_TEMP_FILES_AFTER_UPLOAD = True
 
     # Hide the standard customization widgets
     SUPPORTS_SUB_DIRS = False
diff --git a/src/calibre/devices/interface.py b/src/calibre/devices/interface.py
index b265331ace..925f9eafd0 100644
--- a/src/calibre/devices/interface.py
+++ b/src/calibre/devices/interface.py
@@ -327,12 +327,7 @@ class DevicePlugin(Plugin):
         free space on the device. The text of the FreeSpaceError must contain the
         word "card" if ``on_card`` is not None otherwise it must contain the word "memory".
 
-        :param files: A list of paths and/or file-like objects. If they are paths and
-                      the paths point to temporary files, they may have an additional
-                      attribute, original_file_path pointing to the originals. They may have
-                      another optional attribute, deleted_after_upload which if True means
-                      that the file pointed to by original_file_path will be deleted after
-                      being uploaded to the device.
+        :param files: A list of paths
         :param names: A list of file names that the books should have
                       once uploaded to the device. len(names) == len(files)
         :param metadata: If not None, it is a list of :class:`Metadata` objects.
diff --git a/src/calibre/ebooks/metadata/worker.py b/src/calibre/ebooks/metadata/worker.py
index c335cc4c13..ca8707258b 100644
--- a/src/calibre/ebooks/metadata/worker.py
+++ b/src/calibre/ebooks/metadata/worker.py
@@ -15,7 +15,7 @@ from calibre.utils.ipc.server import Server
 from calibre.ptempfile import PersistentTemporaryDirectory, TemporaryDirectory
 from calibre import prints, isbytestring
 from calibre.constants import filesystem_encoding
-
+from calibre.db.errors import NoSuchFormat
 
 def debug(*args):
     prints(*args)
@@ -201,27 +201,35 @@ class SaveWorker(Thread):
         self.spare_server = spare_server
         self.start()
 
-    def collect_data(self, ids):
+    def collect_data(self, ids, tdir):
         from calibre.ebooks.metadata.opf2 import metadata_to_opf
         data = {}
         for i in set(ids):
-            mi = self.db.get_metadata(i, index_is_id=True, get_cover=True)
+            mi = self.db.get_metadata(i, index_is_id=True, get_cover=True,
+                    cover_as_data=True)
             opf = metadata_to_opf(mi)
             if isbytestring(opf):
                 opf = opf.decode('utf-8')
             cpath = None
-            if mi.cover:
-                cpath = mi.cover
+            if mi.cover_data and mi.cover_data[1]:
+                cpath = os.path.join(tdir, 'cover_%s.jpg'%i)
+                with lopen(cpath, 'wb') as f:
+                    f.write(mi.cover_data[1])
                 if isbytestring(cpath):
                     cpath = cpath.decode(filesystem_encoding)
             formats = {}
             if mi.formats:
                 for fmt in mi.formats:
-                    fpath = self.db.format_abspath(i, fmt, index_is_id=True)
-                    if fpath is not None:
-                        if isbytestring(fpath):
-                            fpath = fpath.decode(filesystem_encoding)
-                        formats[fmt.lower()] = fpath
+                    fpath = os.path.join(tdir, 'fmt_%s.%s'%(i, fmt.lower()))
+                    with lopen(fpath, 'wb') as f:
+                        try:
+                            self.db.copy_format_to(i, fmt, f, index_is_id=True)
+                        except NoSuchFormat:
+                            continue
+                        else:
+                            if isbytestring(fpath):
+                                fpath = fpath.decode(filesystem_encoding)
+                            formats[fmt.lower()] = fpath
             data[i] = [opf, cpath, formats, mi.last_modified.isoformat()]
         return data
 
@@ -244,7 +252,7 @@ class SaveWorker(Thread):
 
         for i, task in enumerate(tasks):
             tids = [x[-1] for x in task]
-            data = self.collect_data(tids)
+            data = self.collect_data(tids, tdir)
             dpath = os.path.join(tdir, '%d.json'%i)
             with open(dpath, 'wb') as f:
                 f.write(json.dumps(data, ensure_ascii=False).encode('utf-8'))
diff --git a/src/calibre/gui2/actions/copy_to_library.py b/src/calibre/gui2/actions/copy_to_library.py
index 7190d1486f..97880faaa1 100644
--- a/src/calibre/gui2/actions/copy_to_library.py
+++ b/src/calibre/gui2/actions/copy_to_library.py
@@ -53,13 +53,18 @@ class Worker(Thread): # {{{
         from calibre.library.database2 import LibraryDatabase2
         newdb = LibraryDatabase2(self.loc)
         for i, x in enumerate(self.ids):
-            mi = self.db.get_metadata(x, index_is_id=True, get_cover=True)
+            mi = self.db.get_metadata(x, index_is_id=True, get_cover=True,
+                    cover_as_data=True)
             self.progress(i, mi.title)
             fmts = self.db.formats(x, index_is_id=True)
             if not fmts: fmts = []
             else: fmts = fmts.split(',')
-            paths = [self.db.format_abspath(x, fmt, index_is_id=True) for fmt in
-                    fmts]
+            paths = []
+            for fmt in fmts:
+                p = self.db.format(x, fmt, index_is_id=True,
+                    as_path=True)
+                if p:
+                    paths.append(p)
             added = False
             if prefs['add_formats_to_existing']:
                 identical_book_list = newdb.find_identical_books(mi)
@@ -75,6 +80,11 @@ class Worker(Thread): # {{{
                 if co is not None:
                     newdb.set_conversion_options(x, 'PIPE', co)
             self.processed.add(x)
+            for path in paths:
+                try:
+                    os.remove(path)
+                except:
+                    pass
 # }}}
 
 class CopyToLibraryAction(InterfaceAction):
diff --git a/src/calibre/gui2/actions/edit_metadata.py b/src/calibre/gui2/actions/edit_metadata.py
index 650947100e..718ece46d2 100644
--- a/src/calibre/gui2/actions/edit_metadata.py
+++ b/src/calibre/gui2/actions/edit_metadata.py
@@ -17,6 +17,7 @@ from calibre.gui2.dialogs.tag_list_editor import TagListEditor
 from calibre.gui2.actions import InterfaceAction
 from calibre.ebooks.metadata import authors_to_string
 from calibre.utils.icu import sort_key
+from calibre.db.errors import NoSuchFormat
 
 class EditMetadataAction(InterfaceAction):
 
@@ -265,7 +266,7 @@ class EditMetadataAction(InterfaceAction):
                                 +'</p>', 'merge_too_many_books', self.gui):
                 return
 
-        dest_id, src_books, src_ids = self.books_to_merge(rows)
+        dest_id, src_ids = self.books_to_merge(rows)
         title = self.gui.library_view.model().db.title(dest_id, index_is_id=True)
         if safe_merge:
             if not confirm('<p>'+_(
@@ -277,7 +278,7 @@ class EditMetadataAction(InterfaceAction):
                 'Please confirm you want to proceed.')%title
             +'</p>', 'merge_books_safe', self.gui):
                 return
-            self.add_formats(dest_id, src_books)
+            self.add_formats(dest_id, self.formats_for_books(rows))
             self.merge_metadata(dest_id, src_ids)
         elif merge_only_formats:
             if not confirm('<p>'+_(
@@ -293,7 +294,7 @@ class EditMetadataAction(InterfaceAction):
                 'Are you <b>sure</b> you want to proceed?')%title
             +'</p>', 'merge_only_formats', self.gui):
                 return
-            self.add_formats(dest_id, src_books)
+            self.add_formats(dest_id, self.formats_for_books(rows))
             self.delete_books_after_merge(src_ids)
         else:
             if not confirm('<p>'+_(
@@ -308,7 +309,7 @@ class EditMetadataAction(InterfaceAction):
                 'Are you <b>sure</b> you want to proceed?')%title
             +'</p>', 'merge_books', self.gui):
                 return
-            self.add_formats(dest_id, src_books)
+            self.add_formats(dest_id, self.formats_for_books(rows))
             self.merge_metadata(dest_id, src_ids)
             self.delete_books_after_merge(src_ids)
             # leave the selection highlight on first selected book
@@ -329,8 +330,22 @@ class EditMetadataAction(InterfaceAction):
                     self.gui.library_view.model().db.add_format(dest_id, fmt, f, index_is_id=True,
                             notify=False, replace=replace)
 
+    def formats_for_books(self, rows):
+        m = self.gui.library_view.model()
+        ans = []
+        for id_ in map(m.id, rows):
+            dbfmts = m.db.formats(id_, index_is_id=True)
+            if dbfmts:
+                for fmt in dbfmts.split(','):
+                    try:
+                        path = m.db.format(id_, fmt, index_is_id=True,
+                                as_path=True)
+                        ans.append(path)
+                    except NoSuchFormat:
+                        continue
+        return ans
+
     def books_to_merge(self, rows):
-        src_books = []
         src_ids = []
         m = self.gui.library_view.model()
         for i, row in enumerate(rows):
@@ -339,22 +354,19 @@ class EditMetadataAction(InterfaceAction):
                 dest_id = id_
             else:
                 src_ids.append(id_)
-                dbfmts = m.db.formats(id_, index_is_id=True)
-                if dbfmts:
-                    for fmt in dbfmts.split(','):
-                        src_books.append(m.db.format_abspath(id_, fmt,
-                            index_is_id=True))
-        return [dest_id, src_books, src_ids]
+        return [dest_id, src_ids]
 
     def delete_books_after_merge(self, ids_to_delete):
         self.gui.library_view.model().delete_books_by_id(ids_to_delete)
 
     def merge_metadata(self, dest_id, src_ids):
         db = self.gui.library_view.model().db
-        dest_mi = db.get_metadata(dest_id, index_is_id=True, get_cover=True)
+        dest_mi = db.get_metadata(dest_id, index_is_id=True)
         orig_dest_comments = dest_mi.comments
+        dest_cover = db.cover(dest_id, index_is_id=True)
+        had_orig_cover = bool(dest_cover)
         for src_id in src_ids:
-            src_mi = db.get_metadata(src_id, index_is_id=True, get_cover=True)
+            src_mi = db.get_metadata(src_id, index_is_id=True)
             if src_mi.comments and orig_dest_comments != src_mi.comments:
                 if not dest_mi.comments:
                     dest_mi.comments = src_mi.comments
@@ -372,8 +384,10 @@ class EditMetadataAction(InterfaceAction):
                     dest_mi.tags = src_mi.tags
                 else:
                     dest_mi.tags.extend(src_mi.tags)
-            if src_mi.cover and not dest_mi.cover:
-                dest_mi.cover = src_mi.cover
+            if not dest_cover:
+                src_cover = db.cover(src_id, index_is_id=True)
+                if src_cover:
+                    dest_cover = src_cover
             if not dest_mi.publisher:
                 dest_mi.publisher = src_mi.publisher
             if not dest_mi.rating:
@@ -382,6 +396,8 @@ class EditMetadataAction(InterfaceAction):
                 dest_mi.series = src_mi.series
                 dest_mi.series_index = src_mi.series_index
         db.set_metadata(dest_id, dest_mi, ignore_errors=False)
+        if not had_orig_cover and dest_cover:
+            db.set_cover(dest_id, dest_cover)
 
         for key in db.field_metadata: #loop thru all defined fields
           if db.field_metadata[key]['is_custom']:
diff --git a/src/calibre/gui2/actions/tweak_epub.py b/src/calibre/gui2/actions/tweak_epub.py
index c9f2d7a8c6..d3924e7cd3 100755
--- a/src/calibre/gui2/actions/tweak_epub.py
+++ b/src/calibre/gui2/actions/tweak_epub.py
@@ -5,6 +5,8 @@ __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
+import os
+
 from calibre.gui2 import error_dialog
 from calibre.gui2.actions import InterfaceAction
 from calibre.gui2.dialogs.tweak_epub import TweakEpub
@@ -30,8 +32,8 @@ class TweakEpubAction(InterfaceAction):
         # Confirm 'EPUB' in formats
         book_id = self.gui.library_view.model().id(row)
         try:
-            path_to_epub = self.gui.library_view.model().db.format_abspath(
-                    book_id, 'EPUB', index_is_id=True)
+            path_to_epub = self.gui.library_view.model().db.format(
+                    book_id, 'EPUB', index_is_id=True, as_path=True)
         except:
             path_to_epub = None
 
@@ -45,6 +47,7 @@ class TweakEpubAction(InterfaceAction):
         if dlg.exec_() == dlg.Accepted:
             self.update_db(book_id, dlg._output)
         dlg.cleanup()
+        os.remove(path_to_epub)
 
     def update_db(self, book_id, rebuilt):
         '''
diff --git a/src/calibre/gui2/add.py b/src/calibre/gui2/add.py
index 44b5bb446b..3dbf4b94df 100644
--- a/src/calibre/gui2/add.py
+++ b/src/calibre/gui2/add.py
@@ -445,6 +445,7 @@ class Saver(QObject): # {{{
         self.pd.setModal(True)
         self.pd.show()
         self.pd.set_min(0)
+        self.pd.set_msg(_('Collecting data, please wait...'))
         self._parent = parent
         self.callback = callback
         self.callback_called = False
diff --git a/src/calibre/gui2/convert/regex_builder.py b/src/calibre/gui2/convert/regex_builder.py
index bf32bf472a..f79e6df3fe 100644
--- a/src/calibre/gui2/convert/regex_builder.py
+++ b/src/calibre/gui2/convert/regex_builder.py
@@ -4,7 +4,7 @@ __license__ = 'GPL 3'
 __copyright__ = '2009, John Schember <john@nachtimwald.com>'
 __docformat__ = 'restructuredtext en'
 
-import re
+import re, os
 
 from PyQt4.QtCore import SIGNAL, Qt, pyqtSignal
 from PyQt4.QtGui import QDialog, QWidget, QDialogButtonBox, \
@@ -134,7 +134,12 @@ class RegexBuilder(QDialog, Ui_RegexBuilder):
                          _('Cannot build regex using the GUI builder without a book.'),
                          show=True)
             return False
-        self.open_book(db.format_abspath(book_id, format, index_is_id=True))
+        fpath = db.format(book_id, format, index_is_id=True,
+            as_path=True)
+        try:
+            self.open_book(fpath)
+        finally:
+            os.remove(fpath)
         return True
 
     def open_book(self, pathtoebook):
diff --git a/src/calibre/gui2/convert/single.py b/src/calibre/gui2/convert/single.py
index 3575fb5ffb..15e670ee32 100644
--- a/src/calibre/gui2/convert/single.py
+++ b/src/calibre/gui2/convert/single.py
@@ -106,7 +106,6 @@ class Config(ResizableDialog, Ui_Dialog):
     Configuration dialog for single book conversion. If accepted, has the
     following important attributes
 
-    input_path - Path to input file
     output_format - Output format (without a leading .)
     input_format  - Input format (without a leading .)
     opf_path - Path to OPF file with user specified metadata
@@ -156,13 +155,10 @@ class Config(ResizableDialog, Ui_Dialog):
         oidx = self.groups.currentIndex().row()
         input_format = self.input_format
         output_format = self.output_format
-        input_path = self.db.format_abspath(self.book_id, input_format,
-                index_is_id=True)
-        self.input_path = input_path
         output_path = 'dummy.'+output_format
         log = Log()
         log.outputs = []
-        self.plumber = Plumber(input_path, output_path, log)
+        self.plumber = Plumber('dummy.'+input_format, output_path, log)
 
         def widget_factory(cls):
             return cls(self.stack, self.plumber.get_option_by_name,
diff --git a/src/calibre/gui2/device.py b/src/calibre/gui2/device.py
index a527cc2e27..d5805a8e09 100644
--- a/src/calibre/gui2/device.py
+++ b/src/calibre/gui2/device.py
@@ -396,8 +396,17 @@ class DeviceManager(Thread): # {{{
                             if DEBUG:
                                 prints(traceback.format_exc(), file=sys.__stdout__)
 
-        return self.device.upload_books(files, names, on_card,
-                                        metadata=metadata, end_session=False)
+        try:
+            return self.device.upload_books(files, names, on_card,
+                    metadata=metadata, end_session=False)
+        finally:
+            if metadata:
+                for mi in metadata:
+                    try:
+                        if mi.cover:
+                            os.remove(mi.cover)
+                    except:
+                        pass
 
     def upload_books(self, done, files, names, on_card=None, titles=None,
                      metadata=None, plugboards=None, add_as_step_to_job=None):
@@ -1072,8 +1081,6 @@ class DeviceMixin(object): # {{{
                             'the device?'), autos):
                         self.iactions['Convert Books'].auto_convert_news(auto, format)
             files = [f for f in files if f is not None]
-            for f in files:
-                f.deleted_after_upload = del_on_upload
             if not files:
                 self.news_to_be_synced = set([])
                 return
@@ -1315,8 +1322,17 @@ class DeviceMixin(object): # {{{
             self.card_b_view if on_card == 'cardb' else self.memory_view
         view.model().resort(reset=False)
         view.model().research()
-        for f in files:
-            getattr(f, 'close', lambda : True)()
+        if files:
+            for f in files:
+                # Remove temporary files
+                try:
+                    rem = not getattr(
+                            self.device_manager.device,
+                            'KEEP_TEMP_FILES_AFTER_UPLOAD', False)
+                    if rem and 'caltmpfmt.' in f:
+                        os.remove(f)
+                except:
+                    pass
 
     def book_on_device(self, id, reset=False):
         '''
diff --git a/src/calibre/gui2/dialogs/metadata_bulk.py b/src/calibre/gui2/dialogs/metadata_bulk.py
index ce21eba00e..7c7c78629c 100644
--- a/src/calibre/gui2/dialogs/metadata_bulk.py
+++ b/src/calibre/gui2/dialogs/metadata_bulk.py
@@ -24,7 +24,7 @@ from calibre.utils.config import prefs, tweaks
 from calibre.utils.magick.draw import identify_data
 from calibre.utils.date import qt_to_dt
 
-def get_cover_data(path): # {{{
+def get_cover_data(stream, ext): # {{{
     from calibre.ebooks.metadata.meta import get_metadata
     old = prefs['read_file_metadata']
     if not old:
@@ -32,8 +32,8 @@ def get_cover_data(path): # {{{
     cdata = area = None
 
     try:
-        mi = get_metadata(open(path, 'rb'),
-                os.path.splitext(path)[1][1:].lower())
+        with stream:
+            mi = get_metadata(stream, ext)
         if mi.cover and os.access(mi.cover, os.R_OK):
             cdata = open(mi.cover).read()
         elif mi.cover_data[1] is not None:
@@ -186,9 +186,10 @@ class MyBlockingBusy(QDialog): # {{{
                 if fmts:
                     covers = []
                     for fmt in fmts.split(','):
-                        fmt = self.db.format_abspath(id, fmt, index_is_id=True)
-                        if not fmt: continue
-                        cdata, area = get_cover_data(fmt)
+                        fmtf = self.db.format(id, fmt, index_is_id=True,
+                                as_file=True)
+                        if fmtf is None: continue
+                        cdata, area = get_cover_data(fmtf, fmt)
                         if cdata:
                             covers.append((cdata, area))
                     covers.sort(key=lambda x: x[1])
diff --git a/src/calibre/gui2/email.py b/src/calibre/gui2/email.py
index b82f421e1e..b9c760abff 100644
--- a/src/calibre/gui2/email.py
+++ b/src/calibre/gui2/email.py
@@ -174,7 +174,8 @@ class EmailMixin(object): # {{{
         else:
             _auto_ids = []
 
-        full_metadata = self.library_view.model().metadata_for(ids)
+        full_metadata = self.library_view.model().metadata_for(ids,
+                get_cover=False)
 
         bad, remove_ids, jobnames = [], [], []
         texts, subjects, attachments, attachment_names = [], [], [], []
diff --git a/src/calibre/gui2/library/models.py b/src/calibre/gui2/library/models.py
index f49c6db59a..40d6e2b6cf 100644
--- a/src/calibre/gui2/library/models.py
+++ b/src/calibre/gui2/library/models.py
@@ -5,8 +5,7 @@ __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
-import shutil, functools, re, os, traceback
-from contextlib import closing
+import functools, re, os, traceback
 from collections import defaultdict
 
 from PyQt4.Qt import (QAbstractTableModel, Qt, pyqtSignal, QIcon, QImage,
@@ -36,14 +35,6 @@ TIME_FMT = '%d %b %Y'
 ALIGNMENT_MAP = {'left': Qt.AlignLeft, 'right': Qt.AlignRight, 'center':
         Qt.AlignHCenter}
 
-class FormatPath(unicode):
-
-    def __new__(cls, path, orig_file_path):
-        ans = unicode.__new__(cls, path)
-        ans.orig_file_path = orig_file_path
-        ans.deleted_after_upload = False
-        return ans
-
 _default_image = None
 
 def default_image():
@@ -391,10 +382,14 @@ class BooksModel(QAbstractTableModel): # {{{
         data = self.current_changed(index, None, False)
         return data
 
-    def metadata_for(self, ids):
+    def metadata_for(self, ids, get_cover=True):
+        '''
+        WARNING: if get_cover=True temp files are created for mi.cover.
+        Remember to delete them once you are done with them.
+        '''
         ans = []
         for id in ids:
-            mi = self.db.get_metadata(id, index_is_id=True, get_cover=True)
+            mi = self.db.get_metadata(id, index_is_id=True, get_cover=get_cover)
             ans.append(mi)
         return ans
 
@@ -449,18 +444,14 @@ class BooksModel(QAbstractTableModel): # {{{
                     format = f
                     break
             if format is not None:
-                pt = PersistentTemporaryFile(suffix='.'+format)
-                with closing(self.db.format(id, format, index_is_id=True,
-                    as_file=True)) as src:
-                    shutil.copyfileobj(src, pt)
-                    pt.flush()
-                    if getattr(src, 'name', None):
-                        pt.orig_file_path = os.path.abspath(src.name)
+                pt = PersistentTemporaryFile(suffix='caltmpfmt.'+format)
+                self.db.copy_format_to(id, format, pt, index_is_id=True)
                 pt.seek(0)
                 if set_metadata:
                     try:
-                        _set_metadata(pt, self.db.get_metadata(id, get_cover=True, index_is_id=True),
-                                  format)
+                        _set_metadata(pt, self.db.get_metadata(
+                            id, get_cover=True, index_is_id=True,
+                            cover_as_data=True), format)
                     except:
                         traceback.print_exc()
                 pt.close()
@@ -468,9 +459,7 @@ class BooksModel(QAbstractTableModel): # {{{
                     if isbytestring(x):
                         x = x.decode(filesystem_encoding)
                     return x
-                name, op = map(to_uni, map(os.path.abspath, (pt.name,
-                    pt.orig_file_path)))
-                ans.append(FormatPath(name, op))
+                ans.append(to_uni(os.path.abspath(pt.name)))
             else:
                 need_auto.append(id)
                 if not exclude_auto:
@@ -499,13 +488,11 @@ class BooksModel(QAbstractTableModel): # {{{
                     break
             if format is not None:
                 pt = PersistentTemporaryFile(suffix='.'+format)
-                with closing(self.db.format(row, format, as_file=True)) as src:
-                    shutil.copyfileobj(src, pt)
-                    pt.flush()
+                self.db.copy_format_to(id, format, pt, index_is_id=True)
                 pt.seek(0)
                 if set_metadata:
-                    _set_metadata(pt, self.db.get_metadata(row, get_cover=True),
-                                  format)
+                    _set_metadata(pt, self.db.get_metadata(row, get_cover=True,
+                        cover_as_data=True), format)
                 pt.close() if paths else pt.seek(0)
                 ans.append(pt)
             else:
diff --git a/src/calibre/gui2/library/views.py b/src/calibre/gui2/library/views.py
index 3ca898d15a..9aa926f5c5 100644
--- a/src/calibre/gui2/library/views.py
+++ b/src/calibre/gui2/library/views.py
@@ -584,14 +584,15 @@ class BooksView(QTableView): # {{{
         m = self.model()
         db = m.db
         rows = self.selectionModel().selectedRows()
-        selected = map(m.id, rows)
+        selected = list(map(m.id, rows))
         ids = ' '.join(map(str, selected))
         md = QMimeData()
         md.setData('application/calibre+from_library', ids)
         fmt = prefs['output_format']
 
         def url_for_id(i):
-            ans = db.format_abspath(i, fmt, index_is_id=True)
+            ans = db.format(i, fmt, index_is_id=True, as_path=True,
+                    preserve_filename=True)
             if ans is None:
                 fmts = db.formats(i, index_is_id=True)
                 if fmts:
@@ -599,14 +600,13 @@ class BooksView(QTableView): # {{{
                 else:
                     fmts = []
                 for f in fmts:
-                    ans = db.format_abspath(i, f, index_is_id=True)
-                    if ans is not None:
-                        break
+                    ans = db.format(i, f, index_is_id=True, as_path=True,
+                            preserve_filename=True)
             if ans is None:
                 ans = db.abspath(i, index_is_id=True)
             return QUrl.fromLocalFile(ans)
 
-        md.setUrls([url_for_id(i) for i in selected])
+        md.setUrls([url_for_id(i) for i in selected[:25]])
         drag = QDrag(self)
         col = self.selectionModel().currentIndex().column()
         md.column_name = self.column_map[col]
diff --git a/src/calibre/gui2/metadata/basic_widgets.py b/src/calibre/gui2/metadata/basic_widgets.py
index f865a5c62c..303cc51c74 100644
--- a/src/calibre/gui2/metadata/basic_widgets.py
+++ b/src/calibre/gui2/metadata/basic_widgets.py
@@ -688,7 +688,8 @@ class FormatsManager(QWidget): # {{{
             else:
                 stream = open(fmt.path, 'r+b')
             try:
-                mi = get_metadata(stream, ext)
+                with stream:
+                    mi = get_metadata(stream, ext)
                 return mi, ext
             except:
                 error_dialog(self, _('Could not read metadata'),
diff --git a/src/calibre/gui2/tools.py b/src/calibre/gui2/tools.py
index 39224c8b35..03b32ca2fb 100644
--- a/src/calibre/gui2/tools.py
+++ b/src/calibre/gui2/tools.py
@@ -51,12 +51,15 @@ def convert_single_ebook(parent, db, book_ids, auto_conversion=False, # {{{
                 #    continue
 
                 mi = db.get_metadata(book_id, True)
-                in_file = db.format_abspath(book_id, d.input_format, True)
+                in_file = PersistentTemporaryFile('.'+d.input_format)
+                with in_file:
+                    db.copy_format_to(book_id, d.input_format, in_file,
+                            index_is_id=True)
 
                 out_file = PersistentTemporaryFile('.' + d.output_format)
                 out_file.write(d.output_format)
                 out_file.close()
-                temp_files = []
+                temp_files = [in_file]
 
                 try:
                     dtitle = unicode(mi.title)
@@ -74,7 +77,7 @@ def convert_single_ebook(parent, db, book_ids, auto_conversion=False, # {{{
                     recs.append(('cover', d.cover_file.name,
                         OptionRecommendation.HIGH))
                     temp_files.append(d.cover_file)
-                args = [in_file, out_file.name, recs]
+                args = [in_file.name, out_file.name, recs]
                 temp_files.append(out_file)
                 jobs.append(('gui_convert_override', args, desc, d.output_format.upper(), book_id, temp_files))
 
@@ -142,12 +145,15 @@ class QueueBulk(QProgressDialog):
         try:
             input_format = get_input_format_for_book(self.db, book_id, None)[0]
             mi, opf_file = create_opf_file(self.db, book_id)
-            in_file = self.db.format_abspath(book_id, input_format, True)
+            in_file = PersistentTemporaryFile('.'+input_format)
+            with in_file:
+                self.db.copy_format_to(book_id, input_format, in_file,
+                        index_is_id=True)
 
             out_file = PersistentTemporaryFile('.' + self.output_format)
             out_file.write(self.output_format)
             out_file.close()
-            temp_files = []
+            temp_files = [in_file]
 
             combined_recs = GuiRecommendations()
             default_recs = bulk_defaults_for_input_format(input_format)
@@ -183,7 +189,7 @@ class QueueBulk(QProgressDialog):
             self.setLabelText(_('Queueing ')+dtitle)
             desc = _('Convert book %d of %d (%s)') % (self.i, len(self.book_ids), dtitle)
 
-            args = [in_file, out_file.name, lrecs]
+            args = [in_file.name, out_file.name, lrecs]
             temp_files.append(out_file)
             self.jobs.append(('gui_convert_override', args, desc, self.output_format.upper(), book_id, temp_files))
 
diff --git a/src/calibre/library/__init__.py b/src/calibre/library/__init__.py
index 2e00db32c4..84a7acbc73 100644
--- a/src/calibre/library/__init__.py
+++ b/src/calibre/library/__init__.py
@@ -61,22 +61,4 @@ def generate_test_db(library_path, # {{{
     print 'Time per record:', t/float(num_of_records)
 # }}}
 
-def cover_load_timing(path=None):
-    from PyQt4.Qt import QApplication, QImage
-    import os, time
-    app = QApplication([])
-    app
-    d = db(path)
-    paths = [d.cover(i, index_is_id=True, as_path=True) for i in
-            d.data.iterallids()]
-    paths = [p for p in paths if (p and os.path.exists(p) and os.path.isfile(p))]
-
-    start = time.time()
-
-    for p in paths:
-        with open(p, 'rb') as f:
-            img = QImage()
-            img.loadFromData(f.read())
-
-    print 'Average load time:', (time.time() - start)/len(paths), 'seconds'
 
diff --git a/src/calibre/library/catalog.py b/src/calibre/library/catalog.py
index 8508fb266f..1b8bb365ab 100644
--- a/src/calibre/library/catalog.py
+++ b/src/calibre/library/catalog.py
@@ -5137,6 +5137,7 @@ Author '{0}':
                     OptionRecommendation.HIGH))
 
             # If cover exists, use it
+            cpath = None
             try:
                 search_text = 'title:"%s" author:%s' % (
                         opts.catalog_title.replace('"', '\\"'), 'calibre')
@@ -5157,5 +5158,10 @@ Author '{0}':
             plumber.merge_ui_recommendations(recommendations)
             plumber.run()
 
+            try:
+                os.remove(cpath)
+            except:
+                pass
+
         # returns to gui2.actions.catalog:catalog_generated()
         return catalog.error
diff --git a/src/calibre/library/database2.py b/src/calibre/library/database2.py
index efb130676a..4c61438e35 100644
--- a/src/calibre/library/database2.py
+++ b/src/calibre/library/database2.py
@@ -12,8 +12,6 @@ import threading, random
 from itertools import repeat
 from math import ceil
 
-from PyQt4.QtGui import QImage
-
 from calibre import prints
 from calibre.ebooks.metadata import (title_sort, author_to_author_sort,
         string_to_authors, authors_to_string)
@@ -27,7 +25,7 @@ from calibre.library.sqlite import connect, IntegrityError
 from calibre.library.prefs import DBPrefs
 from calibre.ebooks.metadata.book.base import Metadata
 from calibre.constants import preferred_encoding, iswindows, filesystem_encoding
-from calibre.ptempfile import PersistentTemporaryFile
+from calibre.ptempfile import PersistentTemporaryFile, base_dir
 from calibre.customize.ui import run_plugins_on_import
 from calibre import isbytestring
 from calibre.utils.filenames import ascii_filename
@@ -39,8 +37,10 @@ from calibre.ebooks import BOOK_EXTENSIONS, check_ebook_format
 from calibre.utils.magick.draw import save_cover_data_to
 from calibre.utils.recycle_bin import delete_file, delete_tree
 from calibre.utils.formatter_functions import load_user_template_functions
+from calibre.db.errors import NoSuchFormat
 
 copyfile = os.link if hasattr(os, 'link') else shutil.copyfile
+SPOOL_SIZE = 30*1024*1024
 
 class Tag(object):
 
@@ -601,14 +601,12 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                 with lopen(os.path.join(tpath, 'cover.jpg'), 'wb') as f:
                     f.write(cdata)
             for format in formats:
-                # Get data as string (can't use file as source and target files may be the same)
-                f = self.format(id, format, index_is_id=True, as_file=True)
-                if f is None:
-                    continue
-                with tempfile.SpooledTemporaryFile(max_size=30*(1024**2)) as stream:
-                    with f:
-                        shutil.copyfileobj(f, stream)
-                    stream.seek(0)
+                with tempfile.SpooledTemporaryFile(max_size=SPOOL_SIZE) as stream:
+                    try:
+                        self.copy_format_to(id, format, stream, index_is_id=True)
+                        stream.seek(0)
+                    except NoSuchFormat:
+                        continue
                     self.add_format(id, format, stream, index_is_id=True,
                         path=tpath, notify=False)
         self.conn.execute('UPDATE books SET path=? WHERE id=?', (path, id))
@@ -661,32 +659,53 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                 continue
 
     def cover(self, index, index_is_id=False, as_file=False, as_image=False,
-              as_path=False):
+            as_path=False):
         '''
         Return the cover image as a bytestring (in JPEG format) or None.
 
-        `as_file` : If True return the image as an open file object
-        `as_image`: If True return the image as a QImage object
+        WARNING: Using as_path will copy the cover to a temp file and return
+        the path to the temp file. You should delete the temp file when you are
+        done with it.
+
+        :param as_file: If True return the image as an open file object (a SpooledTemporaryFile)
+        :param as_image: If True return the image as a QImage object
         '''
-        id = index if  index_is_id else self.id(index)
+        id = index if index_is_id else self.id(index)
         path = os.path.join(self.library_path, self.path(id, index_is_id=True), 'cover.jpg')
         if os.access(path, os.R_OK):
-            if as_path:
-                return path
             try:
                 f = lopen(path, 'rb')
             except (IOError, OSError):
                 time.sleep(0.2)
                 f = lopen(path, 'rb')
-            if as_image:
-                img = QImage()
-                img.loadFromData(f.read())
-                f.close()
-                return img
-            ans = f if as_file else f.read()
-            if ans is not f:
-                f.close()
-            return ans
+            with f:
+                if as_path:
+                    pt = PersistentTemporaryFile('_dbcover.jpg')
+                    with pt:
+                        shutil.copyfileobj(f, pt)
+                    return pt.name
+                if as_file:
+                    ret = tempfile.SpooledTemporaryFile(SPOOL_SIZE)
+                    shutil.copyfileobj(f, ret)
+                    ret.seek(0)
+                else:
+                    ret = f.read()
+                    if as_image:
+                        from PyQt4.Qt import QImage
+                        i = QImage()
+                        i.loadFromData(ret)
+                        ret = i
+            return ret
+
+    def cover_last_modified(self, index, index_is_id=False):
+        id = index if  index_is_id else self.id(index)
+        path = os.path.join(self.library_path, self.path(id, index_is_id=True), 'cover.jpg')
+        try:
+            return utcfromtimestamp(os.stat(path).st_mtime)
+        except:
+            # Cover doesn't exist
+            pass
+        return self.last_modified()
 
     ### The field-style interface. These use field keys.
 
@@ -859,7 +878,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         return (path, mi, sequence)
 
     def get_metadata(self, idx, index_is_id=False, get_cover=False,
-                     get_user_categories=True):
+                     get_user_categories=True, cover_as_data=False):
         '''
         Convenience method to return metadata as a :class:`Metadata` object.
         Note that the list of formats is not verified.
@@ -934,7 +953,12 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         mi.user_categories = user_cat_vals
 
         if get_cover:
-            mi.cover = self.cover(id, index_is_id=True, as_path=True)
+            if cover_as_data:
+                cdata = self.cover(id, index_is_id=True)
+                if cdata:
+                    mi.cover_data = ('jpeg', cdata)
+            else:
+                mi.cover = self.cover(id, index_is_id=True, as_path=True)
         return mi
 
     def has_book(self, mi):
@@ -1099,7 +1123,18 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
             return utcfromtimestamp(os.stat(path).st_mtime)
 
     def format_abspath(self, index, format, index_is_id=False):
-        'Return absolute path to the ebook file of format `format`'
+        '''
+        Return absolute path to the ebook file of format `format`
+
+        WARNING: This method will return a dummy path for a network backend DB,
+        so do not rely on it, use format(..., as_path=True) instead.
+
+        Currently used only in calibredb list, the viewer and the catalogs (via
+        get_data_as_dict()).
+
+        Apart from the viewer, I don't believe any of the others do any file
+        I/O with the results of this call.
+        '''
         id = index if index_is_id else self.id(index)
         try:
             name = self.conn.get('SELECT name FROM data WHERE book=? AND format=?', (id, format), all=False)
@@ -1119,25 +1154,63 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                 shutil.copyfile(candidates[0], fmt_path)
                 return fmt_path
 
-    def format(self, index, format, index_is_id=False, as_file=False, mode='r+b'):
+    def copy_format_to(self, index, fmt, dest, index_is_id=False):
+        '''
+        Copy the format ``fmt`` to the file like object ``dest``. If the
+        specified format does not exist, raises :class:`NoSuchFormat` error.
+        '''
+        path = self.format_abspath(index, fmt, index_is_id=index_is_id)
+        if path is None:
+            id_ = index if index_is_id else self.id(index)
+            raise NoSuchFormat('Record %d has no %s file'%(id_, fmt))
+        with lopen(path, 'rb') as f:
+            shutil.copyfileobj(f, dest)
+        if hasattr(dest, 'flush'):
+            dest.flush()
+
+    def format(self, index, format, index_is_id=False, as_file=False,
+            mode='r+b', as_path=False, preserve_filename=False):
         '''
         Return the ebook format as a bytestring or `None` if the format doesn't exist,
         or we don't have permission to write to the ebook file.
 
-        `as_file`: If True the ebook format is returned as a file object opened in `mode`
+        :param as_file: If True the ebook format is returned as a file object. Note
+                        that the file object is a SpooledTemporaryFile, so if what you want to
+                        do is copy the format to another file, use :method:`copy_format_to`
+                        instead for performance.
+        :param as_path: Copies the format file to a temp file and returns the
+                        path to the temp file
+        :param preserve_filename: If True and returning a path the filename is
+                                  the same as that used in the library. Note that using
+                                  this means that repeated calls yield the same
+                                  temp file (which is re-created each time)
+        :param mode: This is ignored (present for legacy compatibility)
         '''
         path = self.format_abspath(index, format, index_is_id=index_is_id)
         if path is not None:
-            f = lopen(path, mode)
-            try:
-                ret = f if as_file else f.read()
-            except IOError:
-                f.seek(0)
-                out = cStringIO.StringIO()
-                shutil.copyfileobj(f, out)
-                ret = out.getvalue()
-            if not as_file:
-                f.close()
+            with lopen(path, mode) as f:
+                if as_path:
+                    if preserve_filename:
+                        bd = base_dir()
+                        d = os.path.join(bd, 'format_abspath')
+                        try:
+                            os.makedirs(d)
+                        except:
+                            pass
+                        fname = os.path.basename(path)
+                        ret = os.path.join(d, fname)
+                        with lopen(ret, 'wb') as f2:
+                            shutil.copyfileobj(f, f2)
+                    else:
+                        with PersistentTemporaryFile('.'+format.lower()) as pt:
+                            shutil.copyfileobj(f, pt)
+                            ret = pt.name
+                elif as_file:
+                    ret = tempfile.SpooledTemporaryFile(max_size=SPOOL_SIZE)
+                    shutil.copyfileobj(f, ret)
+                    ret.seek(0)
+                else:
+                    ret = f.read()
             return ret
 
     def add_format_with_hooks(self, index, format, fpath, index_is_id=False,
diff --git a/src/calibre/library/save_to_disk.py b/src/calibre/library/save_to_disk.py
index 5f49833564..b5c4e2faf3 100644
--- a/src/calibre/library/save_to_disk.py
+++ b/src/calibre/library/save_to_disk.py
@@ -6,7 +6,7 @@ __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
-import os, traceback, cStringIO, re, shutil
+import os, traceback, cStringIO, re
 
 from calibre.constants import DEBUG
 from calibre.utils.config import Config, StringConfig, tweaks
@@ -238,7 +238,7 @@ def get_components(template, mi, id, timefmt='%b %Y', length=250,
 
 def save_book_to_disk(id_, db, root, opts, length):
     mi = db.get_metadata(id_, index_is_id=True)
-    cover = db.cover(id_, index_is_id=True, as_path=True)
+    cover = db.cover(id_, index_is_id=True)
     plugboards = db.prefs.get('plugboards', {})
 
     available_formats = db.formats(id_, index_is_id=True)
@@ -252,12 +252,20 @@ def save_book_to_disk(id_, db, root, opts, length):
     if fmts:
         fmts = fmts.split(',')
         for fmt in fmts:
-            fpath = db.format_abspath(id_, fmt, index_is_id=True)
+            fpath = db.format(id_, fmt, index_is_id=True, as_path=True)
             if fpath is not None:
                 formats[fmt.lower()] = fpath
 
-    return do_save_book_to_disk(id_, mi, cover, plugboards,
+    try:
+        return do_save_book_to_disk(id_, mi, cover, plugboards,
             formats, root, opts, length)
+    finally:
+        for temp in formats.itervalues():
+            try:
+                os.remove(temp)
+            except:
+                pass
+
 
 
 def do_save_book_to_disk(id_, mi, cover, plugboards,
@@ -289,10 +297,9 @@ def do_save_book_to_disk(id_, mi, cover, plugboards,
             raise
 
     ocover = mi.cover
-    if opts.save_cover and cover and os.access(cover, os.R_OK):
+    if opts.save_cover and cover:
         with open(base_path+'.jpg', 'wb') as f:
-            with open(cover, 'rb') as s:
-                shutil.copyfileobj(s, f)
+            f.write(cover)
         mi.cover = base_name+'.jpg'
     else:
         mi.cover = None
@@ -395,8 +402,13 @@ def save_serialized_to_disk(ids, data, plugboards, root, opts, callback):
             pass
         tb = ''
         try:
-            failed, id, title = do_save_book_to_disk(x, mi, cover, plugboards,
-                    format_map, root, opts, length)
+            with open(cover, 'rb') as f:
+                cover = f.read()
+        except:
+            cover = None
+        try:
+            failed, id, title = do_save_book_to_disk(x, mi, cover,
+                plugboards, format_map, root, opts, length)
             tb = _('Requested formats not available')
         except:
             failed, id, title = True, x, mi.title
diff --git a/src/calibre/library/server/content.py b/src/calibre/library/server/content.py
index 08de4faecd..853ec7829c 100644
--- a/src/calibre/library/server/content.py
+++ b/src/calibre/library/server/content.py
@@ -10,12 +10,13 @@ import re, os, posixpath
 import cherrypy
 
 from calibre import fit_image, guess_type
-from calibre.utils.date import fromtimestamp
+from calibre.utils.date import fromtimestamp, utcnow
 from calibre.library.caches import SortKeyGenerator
 from calibre.library.save_to_disk import find_plugboard
-
-from calibre.utils.magick.draw import save_cover_data_to, Image, \
-        thumbnail as generate_thumbnail
+from calibre.ebooks.metadata import authors_to_string
+from calibre.utils.magick.draw import (save_cover_data_to, Image,
+        thumbnail as generate_thumbnail)
+from calibre.utils.filenames import ascii_filename
 
 plugboard_content_server_value = 'content_server'
 plugboard_content_server_formats = ['epub']
@@ -46,7 +47,7 @@ class ContentServer(object):
     # Utility methods {{{
     def last_modified(self, updated):
         '''
-        Generates a local independent, english timestamp from a datetime
+        Generates a locale independent, english timestamp from a datetime
         object
         '''
         lm = updated.strftime('day, %d month %Y %H:%M:%S GMT')
@@ -151,14 +152,12 @@ class ContentServer(object):
         try:
             cherrypy.response.headers['Content-Type'] = 'image/jpeg'
             cherrypy.response.timeout = 3600
-            cover = self.db.cover(id, index_is_id=True, as_file=True)
+            cover = self.db.cover(id, index_is_id=True)
             if cover is None:
                 cover = self.default_cover
                 updated = self.build_time
             else:
-                with cover as f:
-                    updated = fromtimestamp(os.fstat(f.fileno()).st_mtime)
-                    cover = f.read()
+                updated = self.db.cover_last_modified(id, index_is_id=True)
             cherrypy.response.headers['Last-Modified'] = self.last_modified(updated)
 
             if thumbnail:
@@ -187,9 +186,9 @@ class ContentServer(object):
                 mode='rb')
         if fmt is None:
             raise cherrypy.HTTPError(404, 'book: %d does not have format: %s'%(id, format))
+        mi = self.db.get_metadata(id, index_is_id=True)
         if format == 'EPUB':
             # Get the original metadata
-            mi = self.db.get_metadata(id, index_is_id=True)
 
             # Get any EPUB plugboards for the content server
             plugboards = self.db.prefs.get('plugboards', {})
@@ -203,24 +202,22 @@ class ContentServer(object):
                 newmi = mi
 
             # Write the updated file
-            from tempfile import TemporaryFile
             from calibre.ebooks.metadata.meta import set_metadata
-            raw = fmt.read()
-            fmt = TemporaryFile()
-            fmt.write(raw)
-            fmt.seek(0)
             set_metadata(fmt, newmi, 'epub')
             fmt.seek(0)
 
         mt = guess_type('dummy.'+format.lower())[0]
         if mt is None:
             mt = 'application/octet-stream'
+        au = authors_to_string(mi.authors if mi.authors else [_('Unknown')])
+        title = mi.title if mi.title else _('Unknown')
+        fname = u'%s - %s_%s.%s'%(title[:30], au[:30], id, format.lower())
+        fname = ascii_filename(fname).replace('"', '_')
         cherrypy.response.headers['Content-Type'] = mt
+        cherrypy.response.headers['Content-Disposition'] = \
+                b'attachment; filename="%s"'%fname
         cherrypy.response.timeout = 3600
-        path = getattr(fmt, 'name', None)
-        if path and os.path.exists(path):
-            updated = fromtimestamp(os.stat(path).st_mtime)
-            cherrypy.response.headers['Last-Modified'] = self.last_modified(updated)
+        cherrypy.response.headers['Last-Modified'] = self.last_modified(utcnow())
         return fmt
     # }}}