AZW3 Input: Do not fail to identify JPEG images with BIM headers created with Adobe Photoshop. Fixes #1167985 (Private bug)

src/calibre/ebooks/mobi/reader/mobi8.py

@@ -51,9 +51,11 @@ def reverse_tag_iter(block):
     end = len(block)
     while True:
         pgt = block.rfind(b'>', 0, end)
-        if pgt == -1: break
+        if pgt == -1:
+            break
         plt = block.rfind(b'<', 0, pgt)
-        if plt == -1: break
+        if plt == -1:
+            break
         yield block[plt:pgt+1]
         end = plt
 
@@ -231,12 +233,12 @@ class Mobi8Reader(object):
             flowpart = self.flows[j]
             nstr = '%04d' % j
             m = svg_tag_pattern.search(flowpart)
-            if m != None:
+            if m is not None:
                 # svg
                 typ = 'svg'
                 start = m.start()
                 m2 = image_tag_pattern.search(flowpart)
-                if m2 != None:
+                if m2 is not None:
                     format = 'inline'
                     dir = None
                     fname = None
@@ -406,6 +408,10 @@ class Mobi8Reader(object):
             else:
                 imgtype = what(None, data)
                 if imgtype is None:
+                    from calibre.utils.magick.draw import identify_data
+                    try:
+                        imgtype = identify_data(data)[2]
+                    except Exception:
                         imgtype = 'unknown'
                 href = 'images/%05d.%s'%(fname_idx, imgtype)
                 with open(href.replace('/', os.sep), 'wb') as f: