pdf2txt: do not double encode stdout

pdfminer/converter.py

@@ -164,7 +164,9 @@ class TextConverter(PDFConverter):
         return
 
     def write_text(self, text):
-        self.outfp.write(text.encode(self.codec, 'ignore'))
+        if self.codec:
+            text = text.encode(self.codec, 'ignore')
+        self.outfp.write(text)
         return
 
     def receive_layout(self, ltpage):

tools/pdf2txt.py

@@ -85,6 +85,8 @@ def main(argv):
         outfp = open(outfile, 'wb')
     else:
         outfp = sys.stdout
+        if outfp.encoding is not None:
+            codec = None
     if outtype == 'text':
         device = TextConverter(rsrcmgr, outfp, codec=codec, laparams=laparams,
                                imagewriter=imagewriter)