From 7df1d944ed1e83e5c1dee89e8f0d86ebd538a73d Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Mon, 12 Oct 2009 08:21:09 +0000
Subject: [PATCH] set scale_num on shrink in jpeg2vips

---
 ChangeLog                     | 1 +
 libvips/format/im_jpeg2vips.c | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index d97e42ed..73435bde 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -57,6 +57,7 @@
 - fix up addr calcs on 64-bit machines with >2gb images and inplace ops
   (thanks Christoph)
 - im_generate() checks that im_demand_hint() has been called for this image
+- im_jpeg2vips.c, set scale_num on shrink (thanks Guido)
 
 25/3/09 started 7.18.0
 - revised version numbers
diff --git a/libvips/format/im_jpeg2vips.c b/libvips/format/im_jpeg2vips.c
index ee375942..056da952 100644
--- a/libvips/format/im_jpeg2vips.c
+++ b/libvips/format/im_jpeg2vips.c
@@ -24,6 +24,8 @@
  * 	- added "shrink" parameter
  * 16/6/09
  *	- added "fail" option ... fail on any warnings
+ * 12/10/09
+ * 	- also set scale_num on shrink (thanks Guido)
  */
 
 /*
@@ -448,7 +450,9 @@ read_jpeg_header( struct jpeg_decompress_struct *cinfo,
 	 */
 	jpeg_read_header( cinfo, TRUE );
 	cinfo->scale_denom = shrink;
+	cinfo->scale_num = 1;
 	jpeg_calc_output_dimensions( cinfo );
+
 	*invert_pels = FALSE;
 	switch( cinfo->out_color_space ) {
 	case JCS_GRAYSCALE: