Fix bug 1059: First page of pdf used as cover image

src/calibre/ebooks/metadata/pdf.py

@@ -1,16 +1,37 @@
-__license__   = 'GPL v3'
-__copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
 '''Read meta information from PDF files'''
 
-import sys, os, re
+from __future__ import with_statement
+
+__license__   = 'GPL v3'
+__copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
+
+import sys, os, re, StringIO
 
 from calibre.ebooks.metadata import MetaInformation, authors_to_string, get_parser
-from pyPdf import PdfFileReader
+from calibre.ptempfile import TemporaryDirectory
+from pyPdf import PdfFileReader, PdfFileWriter
+import Image
+try:
+    from calibre.utils.PythonMagickWand import \
+        NewMagickWand, MagickReadImage, MagickSetImageFormat, MagickWriteImage
+    _imagemagick_loaded = True
+except:
+    _imagemagick_loaded = False
 
-def get_metadata(stream):
+def get_metadata(stream, extract_cover=True):
     """ Return metadata as a L{MetaInfo} object """
     mi = MetaInformation(_('Unknown'), [_('Unknown')])
     stream.seek(0)
+
+    if extract_cover and _imagemagick_loaded:
+        try:
+            cdata = get_cover(stream)
+            if cdata is not None:
+                mi.cover_data = ('jpg', cdata)
+        except:
+            import traceback
+            traceback.print_exc()
+    
     try:
         info = PdfFileReader(stream).getDocumentInfo()
         if info.title:
@@ -45,25 +66,66 @@ def set_metadata(stream, mi):
     stream.write(raw)
     stream.seek(0)
 
+def get_cover(stream):
+    try:
+        pdf = PdfFileReader(stream)
+        output = PdfFileWriter()
+        
+        if len(pdf.pages) >= 1:
+            output.addPage(pdf.getPage(0))
+            
+        with TemporaryDirectory('_pdfmeta') as tdir:
+            cover_path = os.path.join(tdir, 'cover.pdf')
+        
+            outputStream = file(cover_path, "wb")
+            output.write(outputStream)
+            outputStream.close()
+            
+            wand = NewMagickWand()
+            MagickReadImage(wand, cover_path)
+            MagickSetImageFormat(wand, 'JPEG')
+            MagickWriteImage(wand, '%s.jpg' % cover_path)
+            
+            img = Image.open('%s.jpg' % cover_path)
+            
+            data = StringIO.StringIO()
+            img.save(data, 'JPEG')
+            return data.getvalue()
+    except:
+        import traceback
+        traceback.print_exc()
+
 def option_parser():
     p = get_parser('pdf')
     p.remove_option('--category')
     p.remove_option('--comment')
+    p.add_option('--get-cover', default=False, action='store_true',
+                      help=_('Extract the cover'))
     return p
             
 def main(args=sys.argv):
-    #p = option_parser()
-    #opts, args = p.parse_args(args)
-    if len(args) != 2:
-        print >>sys.stderr, _('Usage: pdf-meta file.pdf')
-        print >>sys.stderr, _('No filename specified.')
-        return 1
+    p = option_parser()
+    opts, args = p.parse_args(args)
 
-    stream = open(os.path.abspath(os.path.expanduser(args[1])), 'r+b')
-    #mi = MetaInformation(opts.title, opts.authors)
-    #if mi.title or mi.authors:
-    #    set_metadata(stream, mi)
-    print unicode(get_metadata(stream)).encode('utf-8')
+    with open(os.path.abspath(os.path.expanduser(args[1])), 'r+b') as stream:
+        mi = get_metadata(stream, extract_cover=opts.get_cover)
+        changed = False
+        if opts.title:
+            mi.title = opts.title
+            changed = True
+        if opts.authors:
+            mi.authors = opts.authors.split(',')
+            changed = True
+        
+        if changed:
+            set_metadata(stream, mi)
+        print unicode(get_metadata(stream, extract_cover=False)).encode('utf-8')
+        
+    if mi.cover_data[1] is not None:
+        cpath = os.path.splitext(os.path.basename(args[1]))[0] + '_cover.jpg'
+        with open(cpath, 'wb') as f:
+            f.write(mi.cover_data[1])
+            print 'Cover saved to', f.name
         
     return 0