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/*
* 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
*/
/**
* @file
* Perlin noise generator
*/
#include <float.h>
#include "perlin.h"
#include "libavutil/lfg.h"
#include "libavutil/opt.h"
#include "avfilter.h"
#include "internal.h"
#include "formats.h"
#include "video.h"
typedef struct PerlinContext {
const AVClass *class;
int w, h;
AVRational frame_rate;
FFPerlin perlin;
int octaves;
double persistence;
unsigned int random_seed;
enum FFPerlinRandomMode random_mode;
double xscale, yscale, tscale;
uint64_t pts;
} PerlinContext;
#define OFFSET(x) offsetof(PerlinContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption perlin_options[] = {
{ "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="320x240"}, 0, 0, FLAGS },
{ "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="320x240"}, 0, 0, FLAGS },
{ "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
{ "r", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
{ "octaves", "set the number of components to use to generate the noise", OFFSET(octaves), AV_OPT_TYPE_INT, {.i64=1}, 1, INT_MAX, FLAGS },
{ "persistence", "set the octaves persistence", OFFSET(persistence), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS },
{ "xscale", "set x-scale factor", OFFSET(xscale), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS },
{ "yscale", "set y-scale factor", OFFSET(yscale), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS },
{ "tscale", "set t-scale factor", OFFSET(tscale), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, DBL_MAX, FLAGS },
{ "random_mode", "set random mode used to compute initial pattern", OFFSET(random_mode), AV_OPT_TYPE_INT, {.i64=FF_PERLIN_RANDOM_MODE_RANDOM}, 0, FF_PERLIN_RANDOM_MODE_NB-1, FLAGS, .unit = "random_mode" },
{ "random", "compute and use random seed", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_RANDOM}, 0, 0, FLAGS, .unit = "random_mode" },
{ "ken", "use the predefined initial pattern defined by Ken Perlin in the original article", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_KEN}, 0, 0, FLAGS, .unit = "random_mode" },
{ "seed", "use the value specified by random_seed", 0, AV_OPT_TYPE_CONST, {.i64=FF_PERLIN_RANDOM_MODE_SEED}, 0, 0, FLAGS, .unit="random_mode" },
{ "random_seed", "set the seed for filling the initial pattern", OFFSET(random_seed), AV_OPT_TYPE_UINT, {.i64=0}, 0, UINT_MAX, FLAGS },
{ "seed", "set the seed for filling the initial pattern", OFFSET(random_seed), AV_OPT_TYPE_UINT, {.i64=0}, 0, UINT_MAX, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(perlin);
static av_cold int init(AVFilterContext *ctx)
{
PerlinContext *perlin = ctx->priv;
int ret;
if (ret = ff_perlin_init(&perlin->perlin, -1, perlin->octaves, perlin->persistence,
perlin->random_mode, perlin->random_seed)) {
return ret;
}
av_log(ctx, AV_LOG_VERBOSE,
"s:%dx%d r:%d/%d octaves:%d persistence:%f xscale:%f yscale:%f tscale:%f\n",
perlin->w, perlin->h, perlin->frame_rate.num, perlin->frame_rate.den,
perlin->octaves, perlin->persistence,
perlin->xscale, perlin->yscale, perlin->tscale);
return 0;
}
static int config_props(AVFilterLink *outlink)
{
PerlinContext *perlin = outlink->src->priv;
outlink->w = perlin->w;
outlink->h = perlin->h;
outlink->time_base = av_inv_q(perlin->frame_rate);
outlink->frame_rate = perlin->frame_rate;
return 0;
}
static int request_frame(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
PerlinContext *perlin = ctx->priv;
AVFrame *picref = ff_get_video_buffer(outlink, perlin->w, perlin->h);
int i, j;
uint8_t *data0, *data;
double x, y, t;
if (!picref)
return AVERROR(ENOMEM);
picref->sample_aspect_ratio = (AVRational) {1, 1};
picref->pts = perlin->pts++;
picref->duration = 1;
t = perlin->tscale * (perlin->pts * av_q2d(outlink->time_base));
data0 = picref->data[0];
for (i = 0; i < perlin->h; i++) {
y = perlin->yscale * (double)i / perlin->h;
data = data0;
for (j = 0; j < perlin->w; j++) {
double res;
x = perlin->xscale * (double)j / perlin->w;
res = ff_perlin_get(&perlin->perlin, x, y, t);
av_log(ctx, AV_LOG_DEBUG, "x:%f y:%f t:%f => %f\n", x, y, t, res);
*data++ = res * 255;
}
data0 += picref->linesize[0];
}
return ff_filter_frame(outlink, picref);
}
static int query_formats(AVFilterContext *ctx)
{
enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
return ff_set_common_formats_from_list(ctx, pix_fmts);
}
static const AVFilterPad perlin_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.request_frame = request_frame,
.config_props = config_props,
},
};
const AVFilter ff_vsrc_perlin = {
.name = "perlin",
.description = NULL_IF_CONFIG_SMALL("Generate Perlin noise"),
.priv_size = sizeof(PerlinContext),
.priv_class = &perlin_class,
.init = init,
.inputs = NULL,
FILTER_OUTPUTS(perlin_outputs),
FILTER_QUERY_FUNC(query_formats),
};
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