[x265] [PATCH STABLE] regression: refine max-refs tests, since we validate with the HM decoder

[Steve Borho]

# HG changeset patch
# User Steve Borho <steve at borho.org>
# Date 1427515156 18000
#      Fri Mar 27 22:59:16 2015 -0500
# Branch stable
# Node ID 6cd3938d8683841956f255816ead000bdb307a43
# Parent  2da2b9dd7eb3bb724a2436d848921251a69d11e5
regression: refine max-refs tests, since we validate with the HM decoder

diff -r 2da2b9dd7eb3 -r 6cd3938d8683 doc/reST/cli.rst
--- a/doc/reST/cli.rst	Fri Mar 27 13:08:47 2015 -0500
+++ b/doc/reST/cli.rst	Fri Mar 27 22:59:16 2015 -0500
@@ -454,7 +454,20 @@
 	Max number of L0 references to be allowed. This number has a linear
 	multiplier effect on the amount of work performed in motion search,
 	but will generally have a beneficial affect on compression and
-	distortion. Default 3
+	distortion.
+	
+	Note that x265 allows up to 16 L0 references but the HEVC
+	specification only allows a maximum of 8 total reference frames. So
+	if you have B frames enabled only 7 L0 refs are valid and if you
+	have :option:`--b-pyramid` enabled (which is enabled by default in
+	all presets), then only 6 L0 refs are the maximum allowed by the
+	HEVC specification.  If x265 detects that the total reference count
+	is greater than 8, it will issue a warning that the resulting stream
+	is non-compliant and it signals the stream as profile NONE and level
+	NONE but still allows the encode to continue.  Compliant HEVC
+	decoders may refuse to decode such streams.
+	
+	Default 3
 
 .. note::
 	:option:`--profile`, :option:`--level-idc`, and
diff -r 2da2b9dd7eb3 -r 6cd3938d8683 source/test/regression-tests.txt
--- a/source/test/regression-tests.txt	Fri Mar 27 13:08:47 2015 -0500
+++ b/source/test/regression-tests.txt	Fri Mar 27 22:59:16 2015 -0500
@@ -98,8 +98,8 @@
 mobile_calendar_422_ntsc.y4m,--preset superfast --weightp --rd 0
 mobile_calendar_422_ntsc.y4m,--preset veryslow --tskip
 old_town_cross_444_720p50.y4m,--preset faster --rd 1 --tune zero-latency
-old_town_cross_444_720p50.y4m,--preset medium --keyint -1 --no-weightp --ref 16
-old_town_cross_444_720p50.y4m,--preset slow --rdoq-level 1 --early-skip
+old_town_cross_444_720p50.y4m,--preset medium --keyint -1 --no-weightp --ref 6
+old_town_cross_444_720p50.y4m,--preset slow --rdoq-level 1 --early-skip --ref 7 --no-b-pyramid
 old_town_cross_444_720p50.y4m,--preset slower --crf 4 --cu-lossless
 old_town_cross_444_720p50.y4m,--preset superfast --weightp --min-cu 16
 old_town_cross_444_720p50.y4m,--preset ultrafast --weightp --min-cu 32