lavfi: Add vf_ssim360 filter

Customized SSIM for various projections (and stereo formats) of 360 images and videos.

Further contributions by:
Ashok Mathew Kuruvilla
Matthieu Patou
Yu-Hui Wu
Anton Khirnov

Suggested-By: ffmpeg@fb.com
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Changelog

@@ -31,6 +31,7 @@ version <next>:
 - afdelaysrc audio filter
 - WADY DPCM decoder and demuxer
 - CBD2 DPCM decoder
+- ssim360 video filter
 
 
 version 5.1:

libavfilter/Makefile

@@ -486,6 +486,7 @@ OBJS-$(CONFIG_SPLIT_FILTER)                  += split.o
 OBJS-$(CONFIG_SPP_FILTER)                    += vf_spp.o qp_table.o
 OBJS-$(CONFIG_SR_FILTER)                     += vf_sr.o
 OBJS-$(CONFIG_SSIM_FILTER)                   += vf_ssim.o framesync.o
+OBJS-$(CONFIG_SSIM360_FILTER)                += vf_ssim360.o framesync.o
 OBJS-$(CONFIG_STEREO3D_FILTER)               += vf_stereo3d.o
 OBJS-$(CONFIG_STREAMSELECT_FILTER)           += f_streamselect.o framesync.o
 OBJS-$(CONFIG_SUBTITLES_FILTER)              += vf_subtitles.o

libavfilter/allfilters.c

@@ -458,6 +458,7 @@ extern const AVFilter ff_vf_split;
 extern const AVFilter ff_vf_spp;
 extern const AVFilter ff_vf_sr;
 extern const AVFilter ff_vf_ssim;
+extern const AVFilter ff_vf_ssim360;
 extern const AVFilter ff_vf_stereo3d;
 extern const AVFilter ff_vf_streamselect;
 extern const AVFilter ff_vf_subtitles;

libavfilter/version.h

@@ -31,7 +31,7 @@
 
 #include "version_major.h"
 
-#define LIBAVFILTER_VERSION_MINOR  54
+#define LIBAVFILTER_VERSION_MINOR  55
 #define LIBAVFILTER_VERSION_MICRO 100