Update AUTHORS,CHANGELOG,CMakeLists.txt for v3.1.2 Update AUTHORS, CHANGELOG, and CMakeLists.txt for the libaom 3.1.2 release. CMakeLists.txt: Update libtool c:r:a for the libaom 3.1.2 release. The last public release is libaom 3.1.1, which has current=4, revision=1, age=1. The six rules in libtool.html#Updating-version-info are applied as follows: Rule 1: N/A Rule 2: N/A Rule 3: Yes, so increment revision from 1 to 2. Rule 4: No. Rule 5: No. Rule 6: No. The net change is: bump revision only, don’t touch current nor age. BUG=aomedia:3105 Change-Id: I684efdbde0f69700e56d79c6e3b2b38b5dddedca

diff --git a/AUTHORS b/AUTHORS
index d8711a6..f645f59 100644
--- a/AUTHORS
+++ b/AUTHORS

@@ -259,6 +259,7 @@
 Wei-Ting Lin <weitinglin@google.com>
 Wenyao Liu <wenyao.liu@cidana.com>
 Will Bresnahan <bill.wresnahan@gmail.com>
+Xiaoqing Zhu <xzhu@netflix.com>
 Xing Jin <ddvfinite@gmail.com>
 Xin Zhao <xinzzhao@tencent.com>
 Yaowu Xu <yaowu@google.com>

diff --git a/CHANGELOG b/CHANGELOG
index dddef98..f901c43 100644
--- a/CHANGELOG
+++ b/CHANGELOG

@@ -1,3 +1,19 @@
+2021-07-20 v3.1.2
+  This release includes several bug fixes.
+
+  - Bug fixes:
+    exports.cmake: use APPLE and WIN32 and use def for mingw-w64
+    https://aomedia-review.googlesource.com/c/aom/+/139882
+
+    Issue 2993: Incorrect spatial_id when decoding base layer of
+    multi-layer stream
+
+    Issue 3080: Chroma Resampling by Encoder on Y4M Inputs Files Tagged
+    as C420mpeg2
+
+    Issue 3081: Use of uninitialized value $version_extra in
+    concatenation (.) or string at aom/build/cmake/version.pl line 88.
+
 2021-06-08 v3.1.1
   This release includes several bug fixes.
 

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9b37498..26dd379 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt

@@ -43,7 +43,7 @@
 #
 # We set SO_FILE_VERSION = [c-a].a.r
 set(LT_CURRENT 4)
-set(LT_REVISION 1)
+set(LT_REVISION 2)
 set(LT_AGE 1)
 math(EXPR SO_VERSION "${LT_CURRENT} - ${LT_AGE}")
 set(SO_FILE_VERSION "${SO_VERSION}.${LT_AGE}.${LT_REVISION}")