avfilter: add displace video filter

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

Changelog

@@ -16,6 +16,7 @@ version <next>:
 - Screenpresso SPV1 decoding
 - chromaprint fingerprinting muxer
 - ffplay dynamic volume control
+- displace filter
 
 
 version 2.8:

doc/filters.texi

@@ -4750,6 +4750,58 @@ Flags to local 3x3 coordinates maps like this:
     6 7 8
 @end table
 
+@section displace
+
+Displace pixels as indicated by second and third input stream.
+
+It takes three input streams and outputs one stream, the first input is the
+source, and second and third input are displacement maps.
+
+The second input specifies how much to displace pixels along the
+x-axis, while the third input specifies how much to displace pixels
+along the y-axis.
+If one of displacement map streams terminates, last frame from that
+displacement map will be used.
+
+Note that once generated, displacements maps can be reused over and over again.
+
+A description of the accepted options follows.
+
+@table @option
+@item edge
+Set displace behavior for pixels that are out of range.
+
+Available values are:
+@table @samp
+@item blank
+Missing pixels are replaced by black pixels.
+
+@item smear
+Adjacent pixels will spread out to replace missing pixels.
+
+@item wrap
+Out of range pixels are wrapped so they point to pixels of other side.
+@end table
+Default is @samp{smear}.
+
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Add ripple effect to rgb input of video size hd720:
+@example
+ffmpeg -i INPUT -f lavfi -i nullsrc=s=hd720,lutrgb=128:128:128 -f lavfi -i nullsrc=s=hd720,geq='r=128+30*sin(2*PI*X/400+T):g=128+30*sin(2*PI*X/400+T):b=128+30*sin(2*PI*X/400+T)' -lavfi '[0][1][2]displace' OUTPUT
+@end example
+
+@item
+Add wave effect to rgb input of video size hd720:
+@example
+ffmpeg -i INPUT -f lavfi -i nullsrc=hd720,geq='r=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T)):g=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T)):b=128+80*(sin(sqrt((X-W/2)*(X-W/2)+(Y-H/2)*(Y-H/2))/220*2*PI+T))' -lavfi '[1]split[x][y],[0][x][y]displace' OUTPUT
+@end example
+@end itemize
+
 @section drawbox
 
 Draw a colored box on the input image.

libavfilter/Makefile

@@ -126,6 +126,7 @@ OBJS-$(CONFIG_DELOGO_FILTER)                 += vf_delogo.o
 OBJS-$(CONFIG_DESHAKE_FILTER)                += vf_deshake.o
 OBJS-$(CONFIG_DETELECINE_FILTER)             += vf_detelecine.o
 OBJS-$(CONFIG_DILATION_FILTER)               += vf_neighbor.o
+OBJS-$(CONFIG_DISPLACE_FILTER)               += vf_displace.o framesync.o
 OBJS-$(CONFIG_DRAWBOX_FILTER)                += vf_drawbox.o
 OBJS-$(CONFIG_DRAWGRAPH_FILTER)              += f_drawgraph.o
 OBJS-$(CONFIG_DRAWGRID_FILTER)               += vf_drawbox.o

libavfilter/allfilters.c

@@ -148,6 +148,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(DESHAKE,        deshake,        vf);
     REGISTER_FILTER(DETELECINE,     detelecine,     vf);
     REGISTER_FILTER(DILATION,       dilation,       vf);
+    REGISTER_FILTER(DISPLACE,       displace,       vf);
     REGISTER_FILTER(DRAWBOX,        drawbox,        vf);
     REGISTER_FILTER(DRAWGRAPH,      drawgraph,      vf);
     REGISTER_FILTER(DRAWGRID,       drawgrid,       vf);

libavfilter/version.h

@@ -30,8 +30,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   6
-#define LIBAVFILTER_VERSION_MINOR   9
-#define LIBAVFILTER_VERSION_MICRO 101
+#define LIBAVFILTER_VERSION_MINOR  10
+#define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
                                                LIBAVFILTER_VERSION_MINOR, \