PDF Output: Allow using images in the header/footer templates

Images can be loaded using <img> tags with data URIs

src/calibre/ebooks/oeb/display/paged.coffee

@@ -312,6 +312,8 @@ class PagedDisplay
             this.footer.style.setProperty('left', left+'px')
 
     update_header_footer: (pagenum) ->
+        has_images = false
+        this.header_footer_images = []
         if this.hf_style != null
             if pagenum%2 == 1 then cls = "even_page" else cls = "odd_page"
             this.hf_style.innerHTML = "#pdf_page_header_#{ this.hf_uuid } .#{ cls }, #pdf_page_footer_#{ this.hf_uuid } .#{ cls } { display: none }"
@@ -322,9 +324,22 @@ class PagedDisplay
         if this.header != null
             this.header.innerHTML = this.header_template.replace(/_PAGENUM_/g, pagenum+"").replace(/_TITLE_/g, title+"").replace(/_AUTHOR_/g, author+"").replace(/_TOP_LEVEL_SECTION_/g, tl_section+"").replace(/_SECTION_/g, section+"")
             runscripts(this.header)
+            for img in this.header.getElementsByTagName('img')
+                this.header_footer_images.push(img)
+                has_images = true
         if this.footer != null
             this.footer.innerHTML = this.footer_template.replace(/_PAGENUM_/g, pagenum+"").replace(/_TITLE_/g, title+"").replace(/_AUTHOR_/g, author+"").replace(/_TOP_LEVEL_SECTION_/g, tl_section+"").replace(/_SECTION_/g, section+"")
             runscripts(this.footer)
+            for img in this.header.getElementsByTagName('img')
+                this.header_footer_images.push(img)
+                has_images = true
+        has_images
+
+    header_footer_images_loaded: () ->
+        for img in this.header_footer_images
+            if not img.complete
+                return false
+        return true
 
     fit_images: () ->
         # Ensure no images are wider than the available width in a column. Note

src/calibre/ebooks/pdf/render/from_html.py

@@ -159,8 +159,7 @@ class PDFWriter(QObject):
         self.view = QWebView()
         self.page = Page(opts, self.log)
         self.view.setPage(self.page)
-        self.view.setRenderHints(QPainter.Antialiasing|
+        self.view.setRenderHints(QPainter.Antialiasing|QPainter.TextAntialiasing|QPainter.SmoothPixmapTransform)
-                    QPainter.TextAntialiasing|QPainter.SmoothPixmapTransform)
         self.view.loadFinished.connect(self.render_html,
                 type=Qt.QueuedConnection)
         for x in (Qt.Horizontal, Qt.Vertical):
@@ -316,6 +315,16 @@ class PDFWriter(QObject):
                 self.loop.processEvents(self.loop.ExcludeUserInputEvents)
             evaljs('document.getElementById("MathJax_Message").style.display="none";')
 
+    def load_header_footer_images(self):
+        from calibre.utils.monotonic import monotonic
+        evaljs = self.view.page().mainFrame().evaluateJavaScript
+        st = monotonic()
+        while not evaljs('paged_display.header_footer_images_loaded()'):
+            self.loop.processEvents(self.loop.ExcludeUserInputEvents)
+            if monotonic() - st > 5:
+                self.log.warn('Header and footer images have not loaded in 5 seconds, ignoring')
+                break
+
     def get_sections(self, anchor_map, only_top_level=False):
         sections = defaultdict(list)
         ci = os.path.abspath(os.path.normcase(self.current_item))
@@ -395,7 +404,9 @@ class PDFWriter(QObject):
             set_section(col, tl_sections, 'current_tl_section')
             self.doc.init_page()
             if self.header or self.footer:
-                evaljs('paged_display.update_header_footer(%d)'%self.current_page_num)
+                if evaljs('paged_display.update_header_footer(%d)'%self.current_page_num) is True:
+                    self.load_header_footer_images()
+
             self.painter.save()
             mf.render(self.painter)
             self.painter.restore()