From 81c92242d8e6cdde1c8f2b4814b0a9ab0b3f1d7f Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Wed, 21 Aug 2019 17:42:25 +0100
Subject: [PATCH 1/2] relax HEIC threshold

libheic versions change rounding behaviour
---
 test/test-suite/test_foreign.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/test-suite/test_foreign.py b/test/test-suite/test_foreign.py
index 4d8501b6..0ef1e2b6 100644
--- a/test/test-suite/test_foreign.py
+++ b/test/test-suite/test_foreign.py
@@ -830,7 +830,7 @@ class TestForeign:
     def test_heifload(self):
         def heif_valid(im):
             a = im(10, 10)
-            assert_almost_equal_objects(a, [75.0, 86.0, 81.0])
+            assert_almost_equal_objects(a, [75.0, 86.0, 81.0], threshold=2)
             assert im.width == 4032
             assert im.height == 3024
             assert im.bands == 3

From 4b677fb16a95f11ee1fe02502b1565cfc3d2ad19 Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Fri, 23 Aug 2019 15:40:48 +0100
Subject: [PATCH 2/2] make GIF parse less strict

Some GIFs don't follow the standard very closely. Let them through.

See https://github.com/libvips/libvips/issues/1404
---
 ChangeLog                 |  1 +
 libvips/foreign/gifload.c | 13 ++++++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 42848727..870ff49b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,7 @@
 - fix build with MSVC 
 - fix a problem with shinkv tail processing [angelmixu]
 - fix a read one byte beyond buffer bug in jpegload
+- make GIF parsing less strict
 
 24/5/19 started 8.8.1
 - improve realpath() use on older libc
diff --git a/libvips/foreign/gifload.c b/libvips/foreign/gifload.c
index 122e5f40..a76ba040 100644
--- a/libvips/foreign/gifload.c
+++ b/libvips/foreign/gifload.c
@@ -22,6 +22,8 @@
  * 	- init pages to 0 before load
  * 14/2/19
  * 	- rework as a sequential loader ... simpler, much lower mem use
+ * 23/8/18
+ * 	- allow GIF read errors during header scan
  */
 
 /*
@@ -601,11 +603,12 @@ vips_foreign_load_gif_header( VipsForeignLoad *load )
 
 	gif->n_pages = 0;
 
-	do { 
-		if( DGifGetRecordType( gif->file, &record ) == GIF_ERROR ) {
-			vips_foreign_load_gif_error( gif ); 
-			return( -1 ); 
-		}
+	do {
+		/* Don't flag errors during header scan. Some corrupt GIFs
+		 * will fail.
+		 */
+		if( DGifGetRecordType( gif->file, &record ) == GIF_ERROR ) 
+			continue;
 
 		switch( record ) {
 		case IMAGE_DESC_RECORD_TYPE: