avfilter/vf_drawtext: add support for commands

2 files changed, 84 insertions, 23 deletions

diff --git a/doc/filters.texi b/doc/filters.texi
index 9730444337..3afcc23b6a 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -12791,11 +12791,34 @@ Full filter invocation with sendcmd would look like this:
 @example
 sendcmd=c='56.0 drawtext reinit fontsize=56\:fontcolor=green\:text=Hello\\ World'
 @end example
-@end table
 
 If the entire argument can't be parsed or applied as valid values then the filter will
 continue with its existing parameters.
 
+@end table
+
+The following options are also supported as @ref{commands}:
+
+@itemize @bullet
+@item x
+@item y
+@item alpha
+@item fontsize
+@item fontcolor
+@item boxcolor
+@item bordercolor
+@item shadowcolor
+@item box
+@item boxw
+@item boxh
+@item boxborderw
+@item line_spacing
+@item text_align
+@item shadowx
+@item shadowy
+@item borderw
+@end itemize
+
 @subsection Examples
 
 @itemize
diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c
index 59ba3e40c0..4c5c5d8bd6 100644
--- a/libavfilter/vf_drawtext.c
+++ b/libavfilter/vf_drawtext.c
@@ -328,29 +328,30 @@ typedef struct DrawTextContext {
 
 #define OFFSET(x) offsetof(DrawTextContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+#define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
 
 static const AVOption drawtext_options[]= {
     {"fontfile",       "set font file",         OFFSET(fontfile),           AV_OPT_TYPE_STRING, {.str=NULL},  0, 0, FLAGS},
-    {"text",           "set text",              OFFSET(text),               AV_OPT_TYPE_STRING, {.str=NULL},  0, 0, FLAGS},
+    {"text",           "set text",              OFFSET(text),               AV_OPT_TYPE_STRING, {.str=NULL},  0, 0, TFLAGS},
     {"textfile",       "set text file",         OFFSET(textfile),           AV_OPT_TYPE_STRING, {.str=NULL},  0, 0, FLAGS},
-    {"fontcolor",      "set foreground color",  OFFSET(fontcolor.rgba),     AV_OPT_TYPE_COLOR,  {.str="black"}, 0, 0, FLAGS},
+    {"fontcolor",      "set foreground color",  OFFSET(fontcolor.rgba),     AV_OPT_TYPE_COLOR,  {.str="black"}, 0, 0, TFLAGS},
     {"fontcolor_expr", "set foreground color expression", OFFSET(fontcolor_expr), AV_OPT_TYPE_STRING, {.str=""}, 0, 0, FLAGS},
-    {"boxcolor",       "set box color",         OFFSET(boxcolor.rgba),      AV_OPT_TYPE_COLOR,  {.str="white"}, 0, 0, FLAGS},
-    {"bordercolor",    "set border color",      OFFSET(bordercolor.rgba),   AV_OPT_TYPE_COLOR,  {.str="black"}, 0, 0, FLAGS},
-    {"shadowcolor",    "set shadow color",      OFFSET(shadowcolor.rgba),   AV_OPT_TYPE_COLOR,  {.str="black"}, 0, 0, FLAGS},
-    {"box",            "set box",               OFFSET(draw_box),           AV_OPT_TYPE_BOOL,   {.i64=0},     0, 1, FLAGS},
-    {"boxborderw",     "set box borders width", OFFSET(boxborderw),         AV_OPT_TYPE_STRING, {.str="0"},   0, 0, FLAGS},
-    {"line_spacing",   "set line spacing in pixels", OFFSET(line_spacing),  AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, FLAGS},
-    {"fontsize",       "set font size",         OFFSET(fontsize_expr),      AV_OPT_TYPE_STRING, {.str=NULL},  0, 0, FLAGS},
-    {"text_align",     "set text alignment",    OFFSET(text_align),         AV_OPT_TYPE_STRING, {.str="TL"},  0, 0, FLAGS},
-    {"x",              "set x expression",      OFFSET(x_expr),             AV_OPT_TYPE_STRING, {.str="0"},   0, 0, FLAGS},
-    {"y",              "set y expression",      OFFSET(y_expr),             AV_OPT_TYPE_STRING, {.str="0"},   0, 0, FLAGS},
-    {"boxw",           "set box width",         OFFSET(boxw),               AV_OPT_TYPE_INT,    {.i64=0},     0, INT_MAX, FLAGS},
-    {"boxh",           "set box height",        OFFSET(boxh),               AV_OPT_TYPE_INT,    {.i64=0},     0, INT_MAX, FLAGS},
-    {"shadowx",        "set shadow x offset",   OFFSET(shadowx),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, FLAGS},
-    {"shadowy",        "set shadow y offset",   OFFSET(shadowy),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, FLAGS},
-    {"borderw",        "set border width",      OFFSET(borderw),            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},
+    {"boxcolor",       "set box color",         OFFSET(boxcolor.rgba),      AV_OPT_TYPE_COLOR,  {.str="white"}, 0, 0, TFLAGS},
+    {"bordercolor",    "set border color",      OFFSET(bordercolor.rgba),   AV_OPT_TYPE_COLOR,  {.str="black"}, 0, 0, TFLAGS},
+    {"shadowcolor",    "set shadow color",      OFFSET(shadowcolor.rgba),   AV_OPT_TYPE_COLOR,  {.str="black"}, 0, 0, TFLAGS},
+    {"box",            "set box",               OFFSET(draw_box),           AV_OPT_TYPE_BOOL,   {.i64=0},     0, 1, TFLAGS},
+    {"boxborderw",     "set box borders width", OFFSET(boxborderw),         AV_OPT_TYPE_STRING, {.str="0"},   0, 0, TFLAGS},
+    {"line_spacing",   "set line spacing in pixels", OFFSET(line_spacing),  AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, TFLAGS},
+    {"fontsize",       "set font size",         OFFSET(fontsize_expr),      AV_OPT_TYPE_STRING, {.str=NULL},  0, 0, TFLAGS},
+    {"text_align",     "set text alignment",    OFFSET(text_align),         AV_OPT_TYPE_STRING, {.str="TL"},  0, 0, TFLAGS},
+    {"x",              "set x expression",      OFFSET(x_expr),             AV_OPT_TYPE_STRING, {.str="0"},   0, 0, TFLAGS},
+    {"y",              "set y expression",      OFFSET(y_expr),             AV_OPT_TYPE_STRING, {.str="0"},   0, 0, TFLAGS},
+    {"boxw",           "set box width",         OFFSET(boxw),               AV_OPT_TYPE_INT,    {.i64=0},     0, INT_MAX, TFLAGS},
+    {"boxh",           "set box height",        OFFSET(boxh),               AV_OPT_TYPE_INT,    {.i64=0},     0, INT_MAX, TFLAGS},
+    {"shadowx",        "set shadow x offset",   OFFSET(shadowx),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, TFLAGS},
+    {"shadowy",        "set shadow y offset",   OFFSET(shadowy),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, TFLAGS},
+    {"borderw",        "set border width",      OFFSET(borderw),            AV_OPT_TYPE_INT,    {.i64=0},     INT_MIN, INT_MAX, TFLAGS},
+    {"tabsize",        "set tab size",          OFFSET(tabsize),            AV_OPT_TYPE_INT,    {.i64=4},     0, INT_MAX, TFLAGS},
     {"basetime",       "set base time",         OFFSET(basetime),           AV_OPT_TYPE_INT64,  {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX, FLAGS},
 #if CONFIG_LIBFONTCONFIG
     { "font",        "Font name",            OFFSET(font),               AV_OPT_TYPE_STRING, { .str = "Sans" },           .flags = FLAGS },
@@ -360,7 +361,7 @@ static const AVOption drawtext_options[]= {
         {"none",     "set no expansion",                    OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NONE},     0, 0, FLAGS, "expansion"},
         {"normal",   "set normal expansion",                OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NORMAL},   0, 0, FLAGS, "expansion"},
         {"strftime", "set strftime expansion (deprecated)", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_STRFTIME}, 0, 0, FLAGS, "expansion"},
-    {"y_align",   "set the y alignment",    OFFSET(y_align), AV_OPT_TYPE_INT,  {.i64=YA_TEXT}, 0, 2, FLAGS, "y_align"},
+    {"y_align",   "set the y alignment",    OFFSET(y_align), AV_OPT_TYPE_INT,  {.i64=YA_TEXT}, 0, 2, TFLAGS, "y_align"},
         {"text",     "y is referred to the top of the first text line", OFFSET(y_align), AV_OPT_TYPE_CONST, {.i64=YA_TEXT},     0, 0, FLAGS, "y_align"},
         {"baseline", "y is referred to the baseline of the first line", OFFSET(y_align), AV_OPT_TYPE_CONST, {.i64=YA_BASELINE}, 0, 0, FLAGS, "y_align"},
         {"font",     "y is referred to the font defined line metrics",  OFFSET(y_align), AV_OPT_TYPE_CONST, {.i64=YA_FONT},     0, 0, FLAGS, "y_align"},
@@ -371,7 +372,7 @@ static const AVOption drawtext_options[]= {
     {"r",               "set rate (timecode only)",         OFFSET(tc_rate),       AV_OPT_TYPE_RATIONAL, {.dbl=0},    0, INT_MAX, FLAGS},
     {"rate",            "set rate (timecode only)",         OFFSET(tc_rate),       AV_OPT_TYPE_RATIONAL, {.dbl=0},    0, INT_MAX, FLAGS},
     {"reload",          "reload text file at specified frame interval", OFFSET(reload), AV_OPT_TYPE_INT, {.i64=0},    0, INT_MAX, FLAGS},
-    {"alpha",           "apply alpha while rendering",      OFFSET(a_expr),        AV_OPT_TYPE_STRING,   {.str = "1"}, .flags = FLAGS},
+    {"alpha",           "apply alpha while rendering",      OFFSET(a_expr),        AV_OPT_TYPE_STRING,   {.str = "1"}, .flags = TFLAGS},
     {"fix_bounds",      "check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS},
     {"start_number",    "start frame number for n/frame_num variable", OFFSET(start_number), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS},
     {"text_source",     "the source of text", OFFSET(text_source_string), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 1, FLAGS },
@@ -998,6 +999,23 @@ static int query_formats(AVFilterContext *ctx)
     return ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
 }
 
+static int glyph_enu_border_free(void *opaque, void *elem)
+{
+    Glyph *glyph = elem;
+
+    if (glyph->border_glyph != NULL) {
+        for (int t = 0; t < 16; ++t) {
+            if (glyph->border_bglyph[t] != NULL) {
+                FT_Done_Glyph((FT_Glyph)glyph->border_bglyph[t]);
+                glyph->border_bglyph[t] = NULL;
+            }
+        }
+        FT_Done_Glyph(glyph->border_glyph);
+        glyph->border_glyph = NULL;
+    }
+    return 0;
+}
+
 static int glyph_enu_free(void *opaque, void *elem)
 {
     Glyph *glyph = elem;
@@ -1120,8 +1138,28 @@ static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char
 
         ctx->priv = new;
         return config_input(ctx->inputs[0]);
-    } else
-        return AVERROR(ENOSYS);
+    } else {
+        int old_borderw = old->borderw;
+        if ((ret = ff_filter_process_command(ctx, cmd, arg, res, res_len, flags)) < 0) {
+            return ret;
+        }
+        if (old->borderw != old_borderw) {
+            FT_Stroker_Set(old->stroker, old->borderw << 6, FT_STROKER_LINECAP_ROUND,
+                        FT_STROKER_LINEJOIN_ROUND, 0);
+            // Dispose the old border glyphs
+            av_tree_enumerate(old->glyphs, NULL, NULL, glyph_enu_border_free);
+        } else if (strcmp(cmd, "text_align") == 0) {
+            if (validate_text_align(old->text_align) != 0) {
+                av_log(ctx, AV_LOG_ERROR,
+                    "Invalid command value '%s' for 'text_align'\n", old->text_align);
+            }
+        } else if (strcmp(cmd, "fontsize") == 0) {
+            av_expr_free(old->fontsize_pexpr);
+            old->fontsize_pexpr = NULL;
+            old->blank_advance64 = 0;
+        }
+        return config_input(ctx->inputs[0]);
+    }
 
 fail:
     av_log(ctx, AV_LOG_ERROR, "Failed to process command. Continuing with existing parameters.\n");