@@ -2473,6 +2473,9 @@ ratio between the corresponding luma plane number of pixels and the current

 plane ones. E.g. for YUV4:2:0 the values are @code{1,1} for the luma plane, and

 @code{0.5,0.5} for chroma planes.

+@item T

+Time of the current frame, expressed in seconds.

+

 @item p(x, y)

 Return the value of the pixel at location (@var{x},@var{y}) of the current

 plane.

@@ -2503,6 +2506,13 @@ geq=p(W-X\,Y)

 @end example

 @item

+Generate a bidimensional sine wave, with angle @code{PI/3} and a

+wavelength of 100 pixels:

+@example

+geq=128 + 100*sin(2*(PI/100)*(cos(PI/3)*(X-50*T) + sin(PI/3)*Y)):128:128

+@end example

+

+@item

 Generate a fancy enigmatic moving light:

 @example

 nullsrc=s=256x256,geq=random(1)/hypot(X-cos(N*0.07)*W/2-W/2\,Y-sin(N*0.09)*H/2-H/2)^2*1000000*sin(N*0.02):128:128

@@ -30,7 +30,7 @@

 #define LIBAVFILTER_VERSION_MAJOR  3

 #define LIBAVFILTER_VERSION_MINOR  23

-#define LIBAVFILTER_VERSION_MICRO 104

+#define LIBAVFILTER_VERSION_MICRO 105

 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

                                                LIBAVFILTER_VERSION_MINOR, \

@@ -79,8 +79,8 @@ static double lum(void *priv, double x, double y) { return getpix(priv, x, y, 0)

 static double  cb(void *priv, double x, double y) { return getpix(priv, x, y, 1); }

 static double  cr(void *priv, double x, double y) { return getpix(priv, x, y, 2); }

-static const char *const var_names[] = {   "X",   "Y",   "W",   "H",   "N",   "SW",   "SH",        NULL };

-enum                                   { VAR_X, VAR_Y, VAR_W, VAR_H, VAR_N, VAR_SW, VAR_SH, VAR_VARS_NB };

+static const char *const var_names[] = {   "X",   "Y",   "W",   "H",   "N",   "SW",   "SH",   "T",        NULL };

+enum                                   { VAR_X, VAR_Y, VAR_W, VAR_H, VAR_N, VAR_SW, VAR_SH, VAR_T, VAR_VARS_NB };

 static av_cold int geq_init(AVFilterContext *ctx, const char *args)

 {

@@ -160,6 +160,7 @@ static int geq_filter_frame(AVFilterLink *inlink, AVFilterBufferRef *in)

     AVFilterBufferRef *out;

     double values[VAR_VARS_NB] = {

         [VAR_N] = geq->framenum++,

+        [VAR_T] = in->pts == AV_NOPTS_VALUE ? NAN : in->pts * av_q2d(inlink->time_base),

     };

     geq->picref = in;