[FFmpeg-devel] [PATCH] lavfi/hue: add dynamic expression evaluation support
Jérémy Tran
tran.jeremy.av at gmail.com
Wed Sep 12 04:05:20 CEST 2012
---
doc/filters.texi | 45 ++++++++++
libavfilter/vf_hue.c | 228 ++++++++++++++++++++++++++++++++++++++++-----------
2 files changed, 225 insertions(+), 48 deletions(-)
diff --git a/doc/filters.texi b/doc/filters.texi
index 685a3e2..2736350 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -2318,6 +2318,26 @@ Specify the saturation in the [-10,10] range. It accepts a float number and
defaults to 1.0.
@end table
+The @var{h}, @var{H} and @var{s} parameters are expressions containing the
+following constants:
+
+ at table @option
+ at item t
+timestamp expressed in seconds, NAN if the input timestamp is unknown
+
+ at item n
+frame count of the input frame starting from 0
+
+ at item tb
+time base of the input video
+
+ at item pts
+presentation timestamp of the input frame expressed in time base units
+
+ at item r
+frame rate of the input video, NAN if the input frame rate is unknown
+ at end table
+
The options can also be set using the syntax: @var{hue}:@var{saturation}
In this case @var{hue} is expressed in degrees.
@@ -2348,6 +2368,31 @@ h and s, so the following example will issue an error:
@example
hue=PI/2:1
@end example
+
+ at item
+Rotate hue and make the saturation swing between 0
+and 2 over a period of 1 second:
+ at example
+hue="H=2*PI*t: s=sin(2*PI*t)+1"
+ at end example
+
+ at item
+Apply a 3 seconds saturation fade-in:
+ at example
+hue=s=min(t/3,1)
+ at end example
+
+ at item
+The general fade-out equation is:
+ at example
+hue="s=max(0, min(1, (START+DURATION)/DURATION))"
+ at end example
+
+ at item
+Apply a 3 seconds saturation fade-out starting at 5 seconds:
+ at example
+hue="s=max(0, min(1, (8-t)/3))"
+ at end example
@end itemize
@subsection Commands
diff --git a/libavfilter/vf_hue.c b/libavfilter/vf_hue.c
index 1ce231e..e65d88c 100644
--- a/libavfilter/vf_hue.c
+++ b/libavfilter/vf_hue.c
@@ -26,6 +26,7 @@
*/
#include <float.h>
+#include "libavutil/eval.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
@@ -38,52 +39,144 @@
#define HUE_DEFAULT_VAL 0
#define SAT_DEFAULT_VAL 1
+#define HUE_DEFAULT_VAL_STRING AV_STRINGIFY(HUE_DEFAULT_VAL)
+#define SAT_DEFAULT_VAL_STRING AV_STRINGIFY(SAT_DEFAULT_VAL)
+
+#define SAT_MIN_VAL -10
+#define SAT_MAX_VAL 10
+
+static const char *const var_names[] = {
+ "t", // timestamp expressed in seconds
+ "n", // frame count
+ "tb", // timebase
+ "pts", // presentation timestamp expressed in AV_TIME_BASE units
+ "r", // frame rate
+ NULL
+};
+
+enum var_name {
+ VAR_N,
+ VAR_PTS,
+ VAR_R,
+ VAR_T,
+ VAR_TB,
+ VAR_NB
+};
+
typedef struct {
const AVClass *class;
float hue_deg; /* hue expressed in degrees */
float hue; /* hue expressed in radians */
+ char *hue_deg_expr;
+ char *hue_expr;
+ AVExpr *hue_deg_pexpr;
+ AVExpr *hue_pexpr;
float saturation;
+ char *saturation_expr;
+ AVExpr *saturation_pexpr;
int hsub;
int vsub;
int32_t hue_sin;
int32_t hue_cos;
+ int flat_syntax;
+ double var_values[VAR_NB];
} HueContext;
#define OFFSET(x) offsetof(HueContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption hue_options[] = {
- { "h", "set the hue angle degrees", OFFSET(hue_deg), AV_OPT_TYPE_FLOAT,
- { .dbl = -FLT_MAX }, -FLT_MAX, FLT_MAX, FLAGS },
- { "H", "set the hue angle radians", OFFSET(hue), AV_OPT_TYPE_FLOAT,
- { .dbl = -FLT_MAX }, -FLT_MAX, FLT_MAX, FLAGS },
- { "s", "set the saturation value", OFFSET(saturation), AV_OPT_TYPE_FLOAT,
- { .dbl = SAT_DEFAULT_VAL }, -10, 10, FLAGS },
+ { "h", "set the hue angle degrees expression", OFFSET(hue_deg_expr), AV_OPT_TYPE_STRING,
+ { .str = NULL }, .flags = FLAGS },
+ { "H", "set the hue angle radians expression", OFFSET(hue_expr), AV_OPT_TYPE_STRING,
+ { .str = NULL }, .flags = FLAGS },
+ { "s", "set the saturation expression", OFFSET(saturation_expr), AV_OPT_TYPE_STRING,
+ { .str = NULL }, .flags = FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(hue);
+static inline void compute_sin_and_cos(HueContext *hue)
+{
+ /*
+ * Scale the value to the norm of the resulting (U,V) vector, that is
+ * the saturation.
+ * This will be useful in the process_chrominance function.
+ */
+ hue->hue_sin = rint(sin(hue->hue) * (1 << 16) * hue->saturation);
+ hue->hue_cos = rint(cos(hue->hue) * (1 << 16) * hue->saturation);
+}
+
+#define PARSE_EXPRESSION(attr, name) \
+ do { \
+ if ((ret = av_expr_parse(&hue->attr##_pexpr, hue->attr##_expr, var_names, \
+ NULL, NULL, NULL, NULL, 0, ctx)) < 0) { \
+ av_log(ctx, AV_LOG_ERROR, \
+ "Parsing failed evaluating expression " #name "='%s'", \
+ hue->attr##_expr); \
+ hue->attr##_expr = old_##attr##_expr; \
+ hue->attr##_pexpr = old_##attr##_pexpr; \
+ return AVERROR(EINVAL); \
+ } else if (old_##attr##_pexpr) { \
+ av_expr_free(old_##attr##_pexpr); \
+ } \
+ } while (0)
+
static inline int set_options(AVFilterContext *ctx, const char *args)
{
HueContext *hue = ctx->priv;
int n, ret;
char c1 = 0, c2 = 0;
- char *equal;
+ char *old_hue_expr, *old_hue_deg_expr, *old_saturation_expr;
+ AVExpr *old_hue_pexpr, *old_hue_deg_pexpr, *old_saturation_pexpr;
if (args) {
/* named options syntax */
- if (equal = strchr(args, '=')) {
- hue->hue = -FLT_MAX;
- hue->hue_deg = -FLT_MAX;
+ if (strchr(args, '=')) {
+ old_hue_expr = hue->hue_expr;
+ old_hue_deg_expr = hue->hue_deg_expr;
+ old_saturation_expr = hue->saturation_expr;
+
+ old_hue_pexpr = hue->hue_pexpr;
+ old_hue_deg_pexpr = hue->hue_deg_pexpr;
+ old_saturation_pexpr = hue->saturation_pexpr;
+
+ hue->hue_expr = NULL;
+ hue->hue_deg_expr = NULL;
if ((ret = av_set_options_string(hue, args, "=", ":")) < 0)
return ret;
- if (hue->hue != -FLT_MAX && hue->hue_deg != -FLT_MAX) {
+ if (hue->hue_expr && hue->hue_deg_expr) {
av_log(ctx, AV_LOG_ERROR,
"H and h options are incompatible and cannot be specified "
"at the same time\n");
+ hue->hue_expr = old_hue_expr;
+ hue->hue_deg_expr = old_hue_deg_expr;
+
return AVERROR(EINVAL);
}
+
+ if (!hue->hue_expr && !hue->hue_deg_expr) {
+ hue->hue_expr = old_hue_expr;
+ hue->hue_deg_expr = old_hue_deg_expr;
+ }
+
+ if (hue->hue_deg_expr) {
+ PARSE_EXPRESSION(hue_deg, h);
+ hue->hue = hue->hue_deg * M_PI / 180;
+ } else if (hue->hue_expr) {
+ PARSE_EXPRESSION(hue, H);
+ }
+
+ if (hue->saturation_expr) {
+ PARSE_EXPRESSION(saturation, s);
+ }
+
+ hue->flat_syntax = 0;
+
+ av_log(ctx, AV_LOG_DEBUG,
+ "Hexpr:%s hexpr:%s sexpr:%s\n",
+ hue->hue_expr, hue->hue_deg_expr, hue->saturation_expr);
/* compatibility h:s syntax */
} else {
n = sscanf(args, "%f%c%f%c", &hue->hue_deg, &c1, &hue->saturation, &c2);
@@ -94,40 +187,41 @@ static inline int set_options(AVFilterContext *ctx, const char *args)
return AVERROR(EINVAL);
}
- if (hue->saturation < -10 || hue->saturation > 10) {
+ if (hue->saturation < SAT_MIN_VAL || hue->saturation > SAT_MAX_VAL) {
av_log(ctx, AV_LOG_ERROR,
"Invalid value for saturation %0.1f: "
- "must be included between range -10 and +10\n", hue->saturation);
+ "must be included between range %d and +%d\n",
+ hue->saturation, SAT_MIN_VAL, SAT_MAX_VAL);
return AVERROR(EINVAL);
}
+
+ hue->hue = hue->hue_deg * M_PI / 180;
+
+ av_log(ctx, AV_LOG_DEBUG,
+ "H:%0.1f h:%0.1f s:%0.1f\n",
+ hue->hue, hue->hue_deg, hue->saturation);
}
}
+ compute_sin_and_cos(hue);
+
return 0;
}
static av_cold int init(AVFilterContext *ctx, const char *args)
{
HueContext *hue = ctx->priv;
- int ret;
hue->class = &hue_class;
av_opt_set_defaults(hue);
- if ((ret = set_options(ctx, args)) < 0)
- return ret;
+ hue->saturation = SAT_DEFAULT_VAL;
+ hue->hue = HUE_DEFAULT_VAL;
+ hue->hue_deg_pexpr = NULL;
+ hue->hue_pexpr = NULL;
+ hue->flat_syntax = 1;
- if (hue->saturation == -FLT_MAX)
- hue->hue = SAT_DEFAULT_VAL;
- if (hue->hue == -FLT_MAX)
- hue->hue = HUE_DEFAULT_VAL;
- if (hue->hue_deg != -FLT_MAX)
- /* Convert angle from degrees to radians */
- hue->hue = hue->hue_deg * M_PI / 180;
-
- av_log(ctx, AV_LOG_VERBOSE, "hue:%f*PI hue_deg:%f saturation:%f\n",
- hue->hue/M_PI, hue->hue*180/M_PI, hue->saturation);
- return 0;
+ return set_options(ctx, args);
}
static av_cold void uninit(AVFilterContext *ctx)
@@ -159,13 +253,11 @@ static int config_props(AVFilterLink *inlink)
hue->hsub = desc->log2_chroma_w;
hue->vsub = desc->log2_chroma_h;
- /*
- * Scale the value to the norm of the resulting (U,V) vector, that is
- * the saturation.
- * This will be useful in the process_chrominance function.
- */
- hue->hue_sin = rint(sin(hue->hue) * (1 << 16) * hue->saturation);
- hue->hue_cos = rint(cos(hue->hue) * (1 << 16) * hue->saturation);
+
+ hue->var_values[VAR_N] = 0;
+ hue->var_values[VAR_TB] = av_q2d(inlink->time_base);
+ hue->var_values[VAR_R] = inlink->frame_rate.num == 0 || inlink->frame_rate.den == 0 ?
+ NAN : av_q2d(inlink->frame_rate);
return 0;
}
@@ -209,6 +301,58 @@ static void process_chrominance(uint8_t *udst, uint8_t *vdst, const int dst_line
}
}
+static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpic)
+{
+ HueContext *hue = inlink->dst->priv;
+ AVFilterLink *outlink = inlink->dst->outputs[0];
+ AVFilterBufferRef *buf_out;
+
+ outlink->out_buf = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
+ if (!outlink->out_buf)
+ return AVERROR(ENOMEM);
+
+ avfilter_copy_buffer_ref_props(outlink->out_buf, inpic);
+ outlink->out_buf->video->w = outlink->w;
+ outlink->out_buf->video->h = outlink->h;
+ buf_out = avfilter_ref_buffer(outlink->out_buf, ~0);
+ if (!buf_out)
+ return AVERROR(ENOMEM);
+
+ if (!hue->flat_syntax) {
+ hue->var_values[VAR_T] = inpic->pts == AV_NOPTS_VALUE ?
+ NAN : inpic->pts * av_q2d(inlink->time_base);
+ hue->var_values[VAR_PTS] = inpic->pts;
+
+ if (hue->saturation_expr) {
+ hue->saturation = av_expr_eval(hue->saturation_pexpr, hue->var_values, NULL);
+
+ if (hue->saturation < SAT_MIN_VAL || hue->saturation > SAT_MAX_VAL) {
+ hue->saturation = av_clip(hue->saturation, SAT_MIN_VAL, SAT_MAX_VAL);
+ av_log(inlink->dst, AV_LOG_WARNING,
+ "Saturation value not in range [%d,%d]: clipping value to %0.1f\n",
+ SAT_MIN_VAL, SAT_MAX_VAL, hue->saturation);
+ }
+ }
+
+ if (hue->hue_deg_expr) {
+ hue->hue_deg = av_expr_eval(hue->hue_deg_pexpr, hue->var_values, NULL);
+ hue->hue = hue->hue_deg * M_PI / 180;
+ } else if (hue->hue_expr) {
+ hue->hue = av_expr_eval(hue->hue_pexpr, hue->var_values, NULL);
+ }
+
+ hue->var_values[VAR_N] += 1;
+
+ av_log(inlink->dst, AV_LOG_DEBUG,
+ "H:%0.1f s:%0.f t:%0.1f n:%d",
+ hue->hue, hue->saturation, hue->var_values[VAR_T], (int) hue->var_values[VAR_N]);
+
+ compute_sin_and_cos(hue);
+ }
+
+ return ff_start_frame(outlink, buf_out);
+}
+
static int draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
{
HueContext *hue = inlink->dst->priv;
@@ -240,23 +384,10 @@ static int draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
char *res, int res_len, int flags)
{
- HueContext *hue = ctx->priv;
- int ret;
-
if (!strcmp(cmd, "reinit")) {
- if ((ret = set_options(ctx, args)) < 0)
- return ret;
-
- if (hue->hue_deg != -FLT_MAX)
- /* Convert angle from degrees to radians */
- hue->hue = hue->hue_deg * M_PI / 180;
-
- hue->hue_sin = rint(sin(hue->hue) * (1 << 16) * hue->saturation);
- hue->hue_cos = rint(cos(hue->hue) * (1 << 16) * hue->saturation);
+ return set_options(ctx, args);
} else
return AVERROR(ENOSYS);
-
- return 0;
}
AVFilter avfilter_vf_hue = {
@@ -274,6 +405,7 @@ AVFilter avfilter_vf_hue = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
+ .start_frame = start_frame,
.draw_slice = draw_slice,
.config_props = config_props,
.min_perms = AV_PERM_READ,
--
1.7.11.3
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