@@ -3328,6 +3328,9 @@ It can accept an argument: a strftime() format string.

 The time at which the filter is running, expressed in the local time zone.

 It can accept an argument: a strftime() format string.

+@item metadata

+Frame metadata. It must take one argument specifying metadata key.

+

 @item n, frame_num

 The frame number, starting from 0.

@@ -31,7 +31,7 @@

 #define LIBAVFILTER_VERSION_MAJOR  3

 #define LIBAVFILTER_VERSION_MINOR  79

-#define LIBAVFILTER_VERSION_MICRO 100

+#define LIBAVFILTER_VERSION_MICRO 101

 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

                                                LIBAVFILTER_VERSION_MINOR, \

@@ -165,6 +165,7 @@ typedef struct {

     int tc24hmax;                   ///< 1 if timecode is wrapped to 24 hours, 0 otherwise

     int reload;                     ///< reload text file for each frame

     int start_number;               ///< starting frame number for n/frame_num var

+    AVDictionary *metadata;

 } DrawTextContext;

 #define OFFSET(x) offsetof(DrawTextContext, x)

@@ -620,6 +621,17 @@ static int func_frame_num(AVFilterContext *ctx, AVBPrint *bp,

     return 0;

 }

+static int func_metadata(AVFilterContext *ctx, AVBPrint *bp,

+                         char *fct, unsigned argc, char **argv, int tag)

+{

+    DrawTextContext *s = ctx->priv;

+    AVDictionaryEntry *e = av_dict_get(s->metadata, argv[0], NULL, 0);

+

+    if (e && e->value)

+        av_bprintf(bp, "%s", e->value);

+    return 0;

+}

+

 #if !HAVE_LOCALTIME_R

 static void localtime_r(const time_t *t, struct tm *tm)

 {

@@ -677,6 +689,7 @@ static const struct drawtext_function {

     { "localtime", 0, 1, 'L', func_strftime },

     { "frame_num", 0, 0, 0,   func_frame_num },

     { "n",         0, 0, 0,   func_frame_num },

+    { "metadata",  1, 1, 0,   func_metadata },

 };

 static int eval_function(AVFilterContext *ctx, AVBPrint *bp, char *fct,

@@ -985,6 +998,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)

         NAN : frame->pts * av_q2d(inlink->time_base);

     s->var_values[VAR_PICT_TYPE] = frame->pict_type;

+    s->metadata = av_frame_get_metadata(frame);

     draw_text(ctx, frame, frame->width, frame->height);