avfilter: add midequalizer filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Changelog

@@ -20,6 +20,7 @@ version <next>:
 - abitscope multimedia filter
 - Scenarist Closed Captions demuxer and muxer
 - threshold filter
+- midequalizer filter
 
 version 3.2:
 - libopenmpt demuxer

doc/filters.texi

@@ -9643,6 +9643,17 @@ Macroblock size. Default @code{16}.
 Search parameter. Default @code{7}.
 @end table
 
+@section midequalizer
+
+Apply Midway Image Equalization effect using two video streams.
+
+This filter accepts the following option:
+
+@table @option
+@item planes
+Set which planes to process. Default is @code{15}, which is all available planes.
+@end table
+
 @section minterpolate
 
 Convert the video to specified frame rate using motion interpolation.

libavfilter/Makefile

@@ -219,6 +219,7 @@ OBJS-$(CONFIG_MCDEINT_FILTER)                += vf_mcdeint.o
 OBJS-$(CONFIG_MERGEPLANES_FILTER)            += vf_mergeplanes.o framesync.o
 OBJS-$(CONFIG_MESTIMATE_FILTER)              += vf_mestimate.o motion_estimation.o
 OBJS-$(CONFIG_METADATA_FILTER)               += f_metadata.o
+OBJS-$(CONFIG_MIDEQUALIZER_FILTER)           += vf_midequalizer.o framesync.o
 OBJS-$(CONFIG_MINTERPOLATE_FILTER)           += vf_minterpolate.o motion_estimation.o
 OBJS-$(CONFIG_MPDECIMATE_FILTER)             += vf_mpdecimate.o
 OBJS-$(CONFIG_NEGATE_FILTER)                 += vf_lut.o

libavfilter/allfilters.c

@@ -235,6 +235,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(MERGEPLANES,    mergeplanes,    vf);
     REGISTER_FILTER(MESTIMATE,      mestimate,      vf);
     REGISTER_FILTER(METADATA,       metadata,       vf);
+    REGISTER_FILTER(MIDEQUALIZER,   midequalizer,   vf);
     REGISTER_FILTER(MINTERPOLATE,   minterpolate,   vf);
     REGISTER_FILTER(MPDECIMATE,     mpdecimate,     vf);
     REGISTER_FILTER(NEGATE,         negate,         vf);

libavfilter/version.h

@@ -30,7 +30,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   6
-#define LIBAVFILTER_VERSION_MINOR  72
+#define LIBAVFILTER_VERSION_MINOR  73
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \