diff --git a/ANNOUNCE b/ANNOUNCE
index cdce864aa..22c696e88 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1111,6 +1111,16 @@ Version 1.7.0beta74 [December 18, 2015]
     David Drysdale as a result of reports from UBSAN in clang 3.8).
   This changes pngvalid to use BE random numbers; this used to produce
     errors but these should not be fixed as a result of the previous changes.
+  Implemented a prototype of filter selection. This rewrites the code
+    used previously in the heuristics to make it easier to debug and
+    introduces the 'methodical' method, which is intended to be an
+    expensive but reliable way of reducing image size. The code in this
+    commit does not work; the 'methodical' test for success does not take
+    account of data buffered inside zlib and, anyway, it changes the
+    results of pngtest so that the test fails.  This is just a checkpoint
+    of the current state
+  Disabled 'methodical' filter selection code. It is incomplete; it works
+    but does not do anything useful except, maybe, on really enormous images.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
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diff --git a/CHANGES b/CHANGES
index 52d8f87d6..f031edbb6 100644
--- a/CHANGES
+++ b/CHANGES
@@ -5408,8 +5408,18 @@ Version 1.7.0beta74 [December 18, 2015]
     (because png_byte is promoted to int). The libpng exported functions
     png_get_uint_32 and png_get_uint_16 handle this. (Bug reported by
     David Drysdale as a result of reports from UBSAN in clang 3.8).
-  This changes pngvalid to use BE random numbers; this used to produce
+  Changed pngvalid to use BE random numbers; this used to produce
     errors but these should not be fixed as a result of the previous changes.
+  Implemented a prototype of filter selection. This rewrites the code
+    used previously in the heuristics to make it easier to debug and
+    introduces the 'methodical' method, which is intended to be an
+    expensive but reliable way of reducing image size. The code in this
+    commit does not work; the 'methodical' test for success does not take
+    account of data buffered inside zlib and, anyway, it changes the
+    results of pngtest so that the test fails.  This is just a checkpoint
+    of the current state
+  Disabled 'methodical' filter selection code. It is incomplete; it works
+    but does not do anything useful except, maybe, on really enormous images.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/scripts/pnglibconf.h.prebuilt b/scripts/pnglibconf.h.prebuilt
index 9afb7bd90..f78c1af72 100644
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -1,7 +1,8 @@
 /* libpng 1.7.0beta74 STANDARD API DEFINITION */
+
 /* pnglibconf.h - library build configuration */
 
-/* libpng version 1.7.0beta74, December 14, 2015 */
+/* Libpng version 1.7.0beta74, December 18, 2015 */
 
 /* Copyright (c) 1998-2015 Glenn Randers-Pehrson */