From d4700dbf38fc5801356e7b34b1cd630ca21e0387 Mon Sep 17 00:00:00 2001
From: Johannes 'josch' Schauer <josch@mister-muffin.de>
Date: Mon, 27 Aug 2018 11:42:37 +0200
Subject: [PATCH] test.sh: add comment about dct decoding method

---
 test.sh | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test.sh b/test.sh
index fa2dcc2..5cab0b9 100755
--- a/test.sh
+++ b/test.sh
@@ -171,6 +171,9 @@ img2pdf "$tempdir/normal.jpg" "$tempdir/out.pdf"
 # We have to use jpegtopnm and cannot use djpeg because the latter produces
 # slightly different results as well when called like this:
 #    djpeg -dct int -pnm "$tempdir/normal.jpg" > "$tempdir/normal.pnm"
+# An alternative way to compare the JPG would be to require a different DCT
+# method when decoding by setting -define jpeg:dct-method=ifast in the
+# compare command.
 jpegtopnm -dct int "$tempdir/normal.jpg" > "$tempdir/normal.pnm" 2>/dev/null
 
 compare_rendered "$tempdir/out.pdf" "$tempdir/normal.pnm"