[FFmpeg-devel] [PATCH 3/3] libavfilter: vf_drawtext filter support draw text with detection bounding boxes in side_data
Ting Fu
ting.fu at intel.com
Fri May 14 11:47:02 EEST 2021
This feature can be used with dnn detection by setting vf_drawtext's option
text_source=side_data_detection_bboxes, for example:
./ffmpeg -i face.jpeg -vf dnn_detect=dnn_backend=openvino:model=face-detection-adas-0001.xml:\
input=data:output=detection_out:labels=face-detection-adas-0001.label,drawbox=box_source=
side_data_detection_bboxes,drawtext=text_source=side_data_detection_bboxes:fontcolor=green:\
fontsize=40, -y face_detect.jpeg
Please note, the default fontsize of vf_drawtext is 12, which may be too
small to be seen clearly.
Signed-off-by: Ting Fu <ting.fu at intel.com>
---
doc/filters.texi | 8 ++++
libavfilter/vf_drawtext.c | 77 ++++++++++++++++++++++++++++++++++++---
2 files changed, 79 insertions(+), 6 deletions(-)
diff --git a/doc/filters.texi b/doc/filters.texi
index f2ac8c4cc8..d10e6de03d 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -10788,6 +10788,14 @@ parameter @var{text}.
If both @var{text} and @var{textfile} are specified, an error is thrown.
+ at item text_source
+Text source should be set as side_data_detection_bboxes if you want to use text data in
+detection bboxes of side data.
+
+If text source is set, @var{text} and @var{textfile} will be ignored and still use
+text data in detection bboxes of side data. So please do not use this parameter
+if you are not sure about the text source.
+
@item reload
If set to 1, the @var{textfile} will be reloaded before each frame.
Be sure to update it atomically, or it may be read partially, or even fail.
diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c
index 7ea057b812..382d589e26 100644
--- a/libavfilter/vf_drawtext.c
+++ b/libavfilter/vf_drawtext.c
@@ -55,6 +55,7 @@
#include "libavutil/time_internal.h"
#include "libavutil/tree.h"
#include "libavutil/lfg.h"
+#include "libavutil/detection_bbox.h"
#include "avfilter.h"
#include "drawutils.h"
#include "formats.h"
@@ -199,6 +200,8 @@ typedef struct DrawTextContext {
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
+ char *text_source_string; ///< the string to specify text data source
+ enum AVFrameSideDataType text_source;
#if CONFIG_LIBFRIBIDI
int text_shaping; ///< 1 to shape the text before drawing it
#endif
@@ -246,6 +249,7 @@ static const AVOption drawtext_options[]= {
{ "alpha", "apply alpha while rendering", OFFSET(a_expr), AV_OPT_TYPE_STRING, { .str = "1" }, .flags = FLAGS },
{"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 },
#if CONFIG_LIBFRIBIDI
{"text_shaping", "attempt to shape text before drawing", OFFSET(text_shaping), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS},
@@ -690,6 +694,16 @@ out:
}
#endif
+static enum AVFrameSideDataType text_source_string_parse(const char *text_source_string)
+{
+ av_assert0(text_source_string);
+ if (!strcmp(text_source_string, "side_data_detection_bboxes")) {
+ return AV_FRAME_DATA_DETECTION_BBOXES;
+ } else {
+ return AVERROR(EINVAL);
+ }
+}
+
static av_cold int init(AVFilterContext *ctx)
{
int err;
@@ -731,9 +745,28 @@ static av_cold int init(AVFilterContext *ctx)
s->text = av_strdup("");
}
+ if (s->text_source_string) {
+ s->text_source = text_source_string_parse(s->text_source_string);
+ if ((int)s->text_source < 0) {
+ av_log(ctx, AV_LOG_ERROR, "Error text source: %s\n", s->text_source_string);
+ return AVERROR(EINVAL);
+ }
+ }
+
+ if (s->text_source == AV_FRAME_DATA_DETECTION_BBOXES) {
+ if (s->text) {
+ av_log(ctx, AV_LOG_WARNING, "Multiple texts provided, will use text_source only\n");
+ av_free(s->text);
+ }
+ s->text = av_mallocz(AV_DETECTION_BBOX_LABEL_NAME_MAX_SIZE *
+ (AV_NUM_DETECTION_BBOX_CLASSIFY + 1));
+ if (!s->text)
+ return AVERROR(ENOMEM);
+ }
+
if (!s->text) {
av_log(ctx, AV_LOG_ERROR,
- "Either text, a valid file or a timecode must be provided\n");
+ "Either text, a valid file, a timecode or text source must be provided\n");
return AVERROR(EINVAL);
}
@@ -1440,10 +1473,15 @@ continue_on_invalid2:
s->var_values[VAR_LINE_H] = s->var_values[VAR_LH] = s->max_glyph_h;
- 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);
- /* It is necessary if x is expressed from y */
- s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
+ if (s->text_source == AV_FRAME_DATA_DETECTION_BBOXES) {
+ s->var_values[VAR_X] = s->x;
+ s->var_values[VAR_Y] = s->y;
+ } else {
+ 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);
+ /* It is necessary if x is expressed from y */
+ s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
+ }
update_alpha(s);
update_color_with_alpha(s, &fontcolor , s->fontcolor );
@@ -1511,6 +1549,21 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
AVFilterLink *outlink = ctx->outputs[0];
DrawTextContext *s = ctx->priv;
int ret;
+ const AVDetectionBBoxHeader *header = NULL;
+ const AVDetectionBBox *bbox;
+ AVFrameSideData *sd;
+ int loop = 1;
+
+ if (s->text_source == AV_FRAME_DATA_DETECTION_BBOXES && sd) {
+ sd = av_frame_get_side_data(frame, AV_FRAME_DATA_DETECTION_BBOXES);
+ if (sd) {
+ header = (AVDetectionBBoxHeader *)sd->data;
+ loop = header->nb_bboxes;
+ } else {
+ av_log(s, AV_LOG_WARNING, "No detection bboxes.\n");
+ return ff_filter_frame(outlink, frame);
+ }
+ }
if (s->reload) {
if ((ret = load_textfile(ctx)) < 0) {
@@ -1536,7 +1589,19 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
s->var_values[VAR_PKT_SIZE] = frame->pkt_size;
s->metadata = frame->metadata;
- draw_text(ctx, frame, frame->width, frame->height);
+ for (int i = 0; i < loop; i++) {
+ if (header) {
+ bbox = av_get_detection_bbox(header, i);
+ strcpy(s->text, bbox->detect_label);
+ for (int j = 0; j < bbox->classify_count; j++) {
+ strcat(s->text, ", ");
+ strcat(s->text, bbox->classify_labels[j]);
+ }
+ s->x = bbox->x;
+ s->y = bbox->y - s->fontsize;
+ }
+ draw_text(ctx, frame, frame->width, frame->height);
+ }
av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
(int)s->var_values[VAR_N], s->var_values[VAR_T],
--
2.17.1
More information about the ffmpeg-devel
mailing list