a new setting that allows you to skip thumbnail optimization.

paperless.conf.example

@@ -158,7 +158,12 @@ PAPERLESS_CONSUMPTION_DIR="../consume"
 
 # When the consumer detects a duplicate document, it will not touch the
 # original document. This default behavior can be changed here.
-#PAPERLESS_CONSUMER_DELETE_DUPLICATES="false"
+#PAPERLESS_CONSUMER_DELETE_DUPLICATES=false
+
+# Use optipng to optimize thumbnails. This usually reduces the sice of
+# thumbnails by about 20%, but uses considerable compute time during
+# consumption.
+#PAPERLESS_OPTIMIZE_THUMBNAILS=true
 
 # After a document is consumed, Paperless can trigger an arbitrary script if
 # you like.  This script will be passed a number of arguments for you to work

src/documents/parsers.py

@@ -122,6 +122,7 @@ class DocumentParser(LoggingMixin):
 
     def optimise_thumbnail(self, in_path):
 
+        if settings.OPTIMIZE_THUMBNAILS:
             out_path = os.path.join(self.tempdir, "optipng.png")
 
             args = (settings.OPTIPNG_BINARY, "-silent", "-o5", in_path, "-out", out_path)
@@ -132,6 +133,8 @@ class DocumentParser(LoggingMixin):
                 raise ParseError("Optipng failed at {}".format(args))
 
             return out_path
+        else:
+            return in_path
 
     def get_optimised_thumbnail(self):
         return self.optimise_thumbnail(self.get_thumbnail())

src/paperless/settings.py

@@ -320,6 +320,8 @@ CONSUMER_POLLING = int(os.getenv("PAPERLESS_CONSUMER_POLLING", 0))
 
 CONSUMER_DELETE_DUPLICATES = __get_boolean("PAPERLESS_CONSUMER_DELETE_DUPLICATES")
 
+OPTIMIZE_THUMBNAILS = __get_boolean("PAPERLESS_OPTIMIZE_THUMBNAILS", "true")
+
 # The default language that tesseract will attempt to use when parsing
 # documents.  It should be a 3-letter language code consistent with ISO 639.
 OCR_LANGUAGE = os.getenv("PAPERLESS_OCR_LANGUAGE", "eng")