/*
* Copyright (c) 2013 Clément Bœsch
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <float.h> /* DBL_MAX */
#include "libavutil/opt.h"
#include "libavutil/eval.h"
#include "libavutil/avassert.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
static const char *const var_names[] = {
"w", // stream width
"h", // stream height
"n", // frame count
"pts", // presentation timestamp expressed in AV_TIME_BASE units
"r", // frame rate
"t", // timestamp expressed in seconds
"tb", // timebase
NULL
};
enum var_name {
VAR_W,
VAR_H,
VAR_N,
VAR_PTS,
VAR_R,
VAR_T,
VAR_TB,
VAR_NB
};
typedef struct {
const AVClass *class;
const AVPixFmtDescriptor *desc;
int backward;
enum EvalMode { EVAL_MODE_INIT, EVAL_MODE_FRAME, EVAL_MODE_NB } eval_mode;
#define DEF_EXPR_FIELDS(name) AVExpr *name##_pexpr; char *name##_expr; double name
DEF_EXPR_FIELDS(angle);
DEF_EXPR_FIELDS(x0);
DEF_EXPR_FIELDS(y0);
double var_values[VAR_NB];
float *fmap;
int fmap_linesize;
double dmax;
float xscale, yscale;
uint32_t dither;
int do_dither;
AVRational aspect;
AVRational scale;
} VignetteContext;
#define OFFSET(x) offsetof(VignetteContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption vignette_options[] = {
{ "angle", "set lens angle", OFFSET(angle_expr), AV_OPT_TYPE_STRING, {.str="PI/5"}, .flags = FLAGS },
{ "a", "set lens angle", OFFSET(angle_expr), AV_OPT_TYPE_STRING, {.str="PI/5"}, .flags = FLAGS },
{ "x0", "set circle center position on x-axis", OFFSET(x0_expr), AV_OPT_TYPE_STRING, {.str="w/2"}, .flags = FLAGS },
{ "y0", "set circle center position on y-axis", OFFSET(y0_expr), AV_OPT_TYPE_STRING, {.str="h/2"}, .flags = FLAGS },
{ "mode", "set forward/backward mode", OFFSET(backward), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, FLAGS, "mode" },
{ "forward", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0}, INT_MIN, INT_MAX, FLAGS, "mode"},
{ "backward", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1}, INT_MIN, INT_MAX, FLAGS, "mode"},
{ "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
{ "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
{ "frame", "eval expressions for each frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
{ "dither", "set dithering", OFFSET(do_dither), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, FLAGS },
{ "aspect", "set aspect ratio", OFFSET(aspect), AV_OPT_TYPE_RATIONAL, {.dbl = 1}, 0, DBL_MAX, .flags = FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(vignette);
static av_cold int init(AVFilterContext *ctx)
{
VignetteContext *s = ctx->priv;
#define PARSE_EXPR(name) do { \
int ret = av_expr_parse(&s->name##_pexpr, s->name##_expr, var_names, \
NULL, NULL, NULL, NULL, 0, ctx); \
if (ret < 0) { \
av_log(ctx, AV_LOG_ERROR, "Unable to parse expression for '" \
AV_STRINGIFY(name) "'\n"); \
return ret; \
} \
} while (0)
PARSE_EXPR(angle);
PARSE_EXPR(x0);
PARSE_EXPR(y0);
return 0;
}
static av_cold void uninit(AVFilterContext *ctx)
{
VignetteContext *s = ctx->priv;
av_freep(&s->fmap);
av_expr_free(s->angle_pexpr);
av_expr_free(s->x0_pexpr);
av_expr_free(s->y0_pexpr);
}
static int query_formats(AVFilterContext *ctx)
{
static const enum AVPixelFormat pix_fmts[] = {
AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P,
AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P,
AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P,
AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
AV_PIX_FMT_GRAY8,
AV_PIX_FMT_NONE
};
ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
return 0;
}
static double get_natural_factor(const VignetteContext *s, int x, int y)
{
const int xx = (x - s->x0) * s->xscale;
const int yy = (y - s->y0) * s->yscale;
const double dnorm = hypot(xx, yy) / s->dmax;
if (dnorm > 1) {
return 0;
} else {
const double c
= cos(s
->angle
* dnorm
); return (c*c)*(c*c); // do not remove braces, it helps compilers
}
}
#define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
#define TS2T(ts, tb) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts) * av_q2d(tb))
static void update_context(VignetteContext *s, AVFilterLink *inlink, AVFrame *frame)
{
int x, y;
float *dst = s->fmap;
int dst_linesize = s->fmap_linesize;
if (frame) {
s->var_values[VAR_N] = inlink->frame_count;
s->var_values[VAR_T] = TS2T(frame->pts, inlink->time_base);
s->var_values[VAR_PTS] = TS2D(frame->pts);
} else {
s->var_values[VAR_N] = 0;
s->var_values[VAR_T] = NAN;
s->var_values[VAR_PTS] = NAN;
}
s->angle = av_clipf(av_expr_eval(s->angle_pexpr, s->var_values, NULL), 0, M_PI_2);
s->x0 = av_expr_eval(s->x0_pexpr, s->var_values, NULL);
s->y0 = av_expr_eval(s->y0_pexpr, s->var_values, NULL);
if (s->backward) {
for (y = 0; y < inlink->h; y++) {
for (x = 0; x < inlink->w; x++)
dst[x] = 1. / get_natural_factor(s, x, y);
dst += dst_linesize;
}
} else {
for (y = 0; y < inlink->h; y++) {
for (x = 0; x < inlink->w; x++)
dst[x] = get_natural_factor(s, x, y);
dst += dst_linesize;
}
}
}
static inline double get_dither_value(VignetteContext *s)
{
double dv = 0;
if (s->do_dither) {
dv = s->dither / (double)(1LL<<32);
s->dither = s->dither * 1664525 + 1013904223;
}
return dv;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
unsigned x, y;
AVFilterContext *ctx = inlink->dst;
VignetteContext *s = ctx->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFrame *out;
out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
if (s->eval_mode == EVAL_MODE_FRAME)
update_context(s, inlink, in);
if (s->desc->flags & AV_PIX_FMT_FLAG_RGB) {
uint8_t *dst = out->data[0];
const uint8_t *src = in ->data[0];
const float *fmap = s->fmap;
const int dst_linesize = out->linesize[0];
const int src_linesize = in ->linesize[0];
const int fmap_linesize = s->fmap_linesize;
for (y = 0; y < inlink->h; y++) {
uint8_t *dstp = dst;
const uint8_t *srcp = src;
for (x = 0; x < inlink->w; x++, dstp += 3, srcp += 3) {
const float f = fmap[x];
dstp[0] = av_clip_uint8(srcp[0] * f + get_dither_value(s));
dstp[1] = av_clip_uint8(srcp[1] * f + get_dither_value(s));
dstp[2] = av_clip_uint8(srcp[2] * f + get_dither_value(s));
}
dst += dst_linesize;
src += src_linesize;
fmap += fmap_linesize;
}
} else {
int plane;
for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
uint8_t *dst = out->data[plane];
const uint8_t *src = in ->data[plane];
const float *fmap = s->fmap;
const int dst_linesize = out->linesize[plane];
const int src_linesize = in ->linesize[plane];
const int fmap_linesize = s->fmap_linesize;
const int chroma = plane == 1 || plane == 2;
const int hsub = chroma ? s->desc->log2_chroma_w : 0;
const int vsub = chroma ? s->desc->log2_chroma_h : 0;
const int w = FF_CEIL_RSHIFT(inlink->w, hsub);
const int h = FF_CEIL_RSHIFT(inlink->h, vsub);
for (y = 0; y < h; y++) {
uint8_t *dstp = dst;
const uint8_t *srcp = src;
for (x = 0; x < w; x++) {
const double dv = get_dither_value(s);
if (chroma) *dstp++ = av_clip_uint8(fmap[x << hsub] * (*srcp++ - 127) + 127 + dv);
else *dstp++ = av_clip_uint8(fmap[x ] * *srcp++ + dv);
}
dst += dst_linesize;
src += src_linesize;
fmap += fmap_linesize << vsub;
}
}
}
return ff_filter_frame(outlink, out);
}
static int config_props(AVFilterLink *inlink)
{
VignetteContext *s = inlink->dst->priv;
AVRational sar = inlink->sample_aspect_ratio;
s->desc = av_pix_fmt_desc_get(inlink->format);
s->var_values[VAR_W] = inlink->w;
s->var_values[VAR_H] = inlink->h;
s->var_values[VAR_TB] = av_q2d(inlink->time_base);
s->var_values[VAR_R] = inlink->frame_rate.num == 0 || inlink->frame_rate.den == 0 ?
NAN : av_q2d(inlink->frame_rate);
if (!sar.num || !sar.den)
sar.num = sar.den = 1;
if (sar.num > sar.den) {
s->xscale = av_q2d(av_div_q(sar, s->aspect));
s->yscale = 1;
} else {
s->yscale = av_q2d(av_div_q(s->aspect, sar));
s->xscale = 1;
}
s->dmax = hypot(inlink->w / 2., inlink->h / 2.);
av_log(s, AV_LOG_DEBUG, "xscale=%f yscale=%f dmax=%f\n",
s->xscale, s->yscale, s->dmax);
s->fmap_linesize = FFALIGN(inlink->w, 32);
s->fmap = av_malloc(s->fmap_linesize * inlink->h * sizeof(*s->fmap));
if (!s->fmap)
return AVERROR(ENOMEM);
if (s->eval_mode == EVAL_MODE_INIT)
update_context(s, inlink, NULL);
return 0;
}
static const AVFilterPad vignette_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_props,
},
{ NULL }
};
static const AVFilterPad vignette_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter avfilter_vf_vignette = {
.name = "vignette",
.description = NULL_IF_CONFIG_SMALL("Make or reverse a vignette effect."),
.priv_size = sizeof(VignetteContext),
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.inputs = vignette_inputs,
.outputs = vignette_outputs,
.priv_class = &vignette_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};