lavfi/drawtext: add generic timeline interface and deprecate "draw".

doc/filters.texi

@@ -3239,16 +3239,6 @@ Either a string (e.g. "yellow") or in 0xRRGGBB[AA] format
 (e.g. "0xff00ff"), possibly followed by an alpha specifier.
 The default value of @var{boxcolor} is "white".
 
-@item draw
-Set an expression which specifies if the text should be drawn. If the
-expression evaluates to 0, the text is not drawn. This is useful for
-specifying that the text should be drawn only when specific conditions
-are met.
-
-Default value is "1".
-
-See below for the list of accepted constants and functions.
-
 @item expansion
 Select how the @var{text} is expanded. Can be either @code{none},
 @code{strftime} (deprecated) or
@@ -3548,7 +3538,7 @@ drawtext="fontsize=60:fontfile=FreeSerif.ttf:fontcolor=green:text=g:x=(w-max_gly
 @item
 Show text for 1 second every 3 seconds:
 @example
-drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:draw=lt(mod(t\,3)\,1):text='blink'"
+drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:enable=lt(mod(t\,3)\,1):text='blink'"
 @end example
 
 @item

libavfilter/version.h

@@ -31,7 +31,7 @@
 
 #define LIBAVFILTER_VERSION_MAJOR  3
 #define LIBAVFILTER_VERSION_MINOR  83
-#define LIBAVFILTER_VERSION_MICRO 101
+#define LIBAVFILTER_VERSION_MICRO 102
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
                                                LIBAVFILTER_VERSION_MINOR, \
@@ -82,5 +82,8 @@
 #ifndef FF_API_OLD_GRAPH_PARSE
 #define FF_API_OLD_GRAPH_PARSE              (LIBAVFILTER_VERSION_MAJOR < 4)
 #endif
+#ifndef FF_API_DRAWTEXT_OLD_TIMELINE
+#define FF_API_DRAWTEXT_OLD_TIMELINE        (LIBAVFILTER_VERSION_MAJOR < 4)
+#endif
 
 #endif /* AVFILTER_VERSION_H */

libavfilter/vf_drawtext.c

@@ -155,9 +155,11 @@ typedef struct {
     AVExpr *x_pexpr, *y_pexpr;      ///< parsed expressions for x and y
     int64_t basetime;               ///< base pts time in the real world for display
     double var_values[VAR_VARS_NB];
+#if FF_API_DRAWTEXT_OLD_TIMELINE
     char   *draw_expr;              ///< expression for draw
     AVExpr *draw_pexpr;             ///< parsed expression for draw
     int draw;                       ///< set to zero to prevent drawing
+#endif
     AVLFG  prng;                    ///< random
     char       *tc_opt_string;      ///< specified timecode option string
     AVRational  tc_rate;            ///< frame rate for timecode
@@ -186,7 +188,9 @@ static const AVOption drawtext_options[]= {
     {"shadowy",     "set y",                OFFSET(shadowy),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN,  INT_MAX , FLAGS},
     {"tabsize",     "set tab size",         OFFSET(tabsize),            AV_OPT_TYPE_INT,    {.i64=4},     0,        INT_MAX , FLAGS},
     {"basetime",    "set base time",        OFFSET(basetime),           AV_OPT_TYPE_INT64,  {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX , FLAGS},
-    {"draw",        "if false do not draw", OFFSET(draw_expr),          AV_OPT_TYPE_STRING, {.str="1"},   CHAR_MIN, CHAR_MAX, FLAGS},
+#if FF_API_DRAWTEXT_OLD_TIMELINE
+    {"draw",        "if false do not draw (deprecated)", OFFSET(draw_expr), AV_OPT_TYPE_STRING, {.str=NULL},   CHAR_MIN, CHAR_MAX, FLAGS},
+#endif
 
     {"expansion", "set the expansion mode", OFFSET(exp_mode), AV_OPT_TYPE_INT, {.i64=EXP_NORMAL}, 0, 2, FLAGS, "expansion"},
         {"none",     "set no expansion",                    OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NONE},     0, 0, FLAGS, "expansion"},
@@ -423,6 +427,12 @@ static av_cold int init(AVFilterContext *ctx)
     DrawTextContext *s = ctx->priv;
     Glyph *glyph;
 
+#if FF_API_DRAWTEXT_OLD_TIMELINE
+    if (s->draw_expr)
+        av_log(ctx, AV_LOG_WARNING, "'draw' option is deprecated and will be removed soon, "
+               "you are encouraged to use the generic timeline support through the 'enable' option\n");
+#endif
+
     if (!s->fontfile && !CONFIG_FONTCONFIG) {
         av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
         return AVERROR(EINVAL);
@@ -518,8 +528,10 @@ static av_cold void uninit(AVFilterContext *ctx)
 
     av_expr_free(s->x_pexpr);
     av_expr_free(s->y_pexpr);
+#if FF_API_DRAWTEXT_OLD_TIMELINE
     av_expr_free(s->draw_pexpr);
     s->x_pexpr = s->y_pexpr = s->draw_pexpr = NULL;
+#endif
     av_freep(&s->positions);
     s->nb_positions = 0;
 
@@ -564,16 +576,25 @@ static int config_input(AVFilterLink *inlink)
 
     av_expr_free(s->x_pexpr);
     av_expr_free(s->y_pexpr);
+#if FF_API_DRAWTEXT_OLD_TIMELINE
     av_expr_free(s->draw_pexpr);
     s->x_pexpr = s->y_pexpr = s->draw_pexpr = NULL;
+#else
+    s->x_pexpr = s->y_pexpr = NULL;
+#endif
+
     if ((ret = av_expr_parse(&s->x_pexpr, s->x_expr, var_names,
                              NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
         (ret = av_expr_parse(&s->y_pexpr, s->y_expr, var_names,
-                             NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
-        (ret = av_expr_parse(&s->draw_pexpr, s->draw_expr, var_names,
                              NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
 
         return AVERROR(EINVAL);
+#if FF_API_DRAWTEXT_OLD_TIMELINE
+    if (s->draw_expr &&
+        (ret = av_expr_parse(&s->draw_pexpr, s->draw_expr, var_names,
+                             NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
+        return ret;
+#endif
 
     return 0;
 }
@@ -955,10 +976,16 @@ static int draw_text(AVFilterContext *ctx, AVFrame *frame,
     s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
     s->y = s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, &s->prng);
     s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
+#if FF_API_DRAWTEXT_OLD_TIMELINE
+    if (s->draw_pexpr){
     s->draw = av_expr_eval(s->draw_pexpr, s->var_values, &s->prng);
 
     if(!s->draw)
         return 0;
+    }
+    if (ctx->is_disabled)
+        return 0;
+#endif
 
     box_w = FFMIN(width - 1 , max_text_line_w);
     box_h = FFMIN(height - 1, y + s->max_glyph_h);
@@ -1042,4 +1069,9 @@ AVFilter avfilter_vf_drawtext = {
     .inputs    = avfilter_vf_drawtext_inputs,
     .outputs   = avfilter_vf_drawtext_outputs,
     .process_command = command,
+#if FF_API_DRAWTEXT_OLD_TIMELINE
+    .flags           = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
+#else
+    .flags           = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
+#endif
 };