[FFmpeg-devel] [PATCH] lavfi/hue: add dynamic expression support
Stefano Sabatini
stefasab at gmail.com
Mon Sep 10 11:33:56 CEST 2012
On date Monday 2012-09-10 05:58:28 +0200, Jérémy Tran encoded:
> ---
> doc/filters.texi | 45 ++++++++++
> libavfilter/vf_hue.c | 231 ++++++++++++++++++++++++++++++++++++++++-----------
> 2 files changed, 228 insertions(+), 48 deletions(-)
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 685a3e2..e2eaf26 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?
> +
> + 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..f8756eb8 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 +39,148 @@
> #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(pexpr, expr, old_pexpr, old_expr, name) \
> + do { \
> + if ((ret = av_expr_parse(&pexpr, expr, var_names, \
> + NULL, NULL, NULL, NULL, 0, ctx)) < 0) { \
> + av_log(ctx, AV_LOG_ERROR, \
> + "Parsing failed evaluating expression " #name "='%s'", \
> + expr); \
> + expr = old_expr; \
> + pexpr = old_pexpr; \
> + return AVERROR(EINVAL); \
> + } else { \
> + if (old_pexpr) \
> + av_expr_free(old_pexpr); \
> + } \
else if (...)
> + } 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_expr || hue->hue_deg_expr) {
> + if (hue->hue_deg_expr) {
> + PARSE_EXPRESSION(hue->hue_deg_pexpr, hue->hue_deg_expr,
> + old_hue_deg_pexpr, old_hue_deg_expr,
> + h);
This can be further simplified to PARSE_EXPRESSION(hue_deg, h);
> + hue->hue = hue->hue_deg * M_PI / 180;
> + } else if (hue->hue_expr) {
> + PARSE_EXPRESSION(hue->hue_pexpr, hue->hue_expr,
> + old_hue_pexpr, old_hue_expr,
> + H);
> + }
> + }
> + if (hue->saturation_expr) {
> + PARSE_EXPRESSION(hue->saturation_pexpr, hue->saturation_expr,
> + old_saturation_pexpr, old_saturation_expr,
> + s);
> + }
> +
> + hue->flat_syntax = 0;
> /* compatibility h:s syntax */
> } else {
> n = sscanf(args, "%f%c%f%c", &hue->hue_deg, &c1, &hue->saturation, &c2);
> @@ -94,40 +191,41 @@ 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;
> }
> }
>
> + compute_sin_and_cos(hue);
> +
> + av_log(ctx, AV_LOG_DEBUG,
> + "H:%0.1f h:%0.1f s:%0.1f\n",
> + hue->hue, hue->hue_deg, hue->saturation);
This works only with flat syntax, right?
You could set two logs, one within the flat and one within the other
block, which shows the expressions.
> +
> 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 +257,11 @@ 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 == 1 && inlink->frame_rate.den == 0 ?
inlink->frame_rate.num == 0 || inlink->frame_rate.den == 0
> + NAN : av_q2d(inlink->frame_rate);
>
> return 0;
> }
> @@ -209,6 +305,57 @@ 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_N] += 1;
This should be post-incremented, if we assume that n starts from 0.
[...]
Looks good otherwise.
Note: as we discovered dealing with flat/named options is rather
clumsy, Nicolas pending work should greatly help this and might
significantly simplify this patch (but can be done post-commit).
--
FFmpeg = Foolish & Foolish Maxi Plastic Erotic Gadget
More information about the ffmpeg-devel
mailing list