/*
* Copyright (c) 2002 Michael Niedermayer <michaelni@gmx.at>
* Copyright (c) 2013 Paul B Mahol
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
* noise generator
*/
#include "libavutil/opt.h"
#include "libavutil/imgutils.h"
#include "libavutil/lfg.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#define MAX_NOISE 4096
#define MAX_SHIFT 1024
#define MAX_RES (MAX_NOISE-MAX_SHIFT)
#define NOISE_UNIFORM 1
#define NOISE_TEMPORAL 2
#define NOISE_QUALITY 4
#define NOISE_AVERAGED 8
#define NOISE_PATTERN 16
typedef struct {
int strength;
unsigned flags;
int shiftptr;
AVLFG lfg;
int seed;
int8_t *noise;
int8_t *prev_shift[MAX_RES][3];
} FilterParams;
typedef struct {
const AVClass *class;
int nb_planes;
int linesize[4];
int height[4];
FilterParams all;
FilterParams param[4];
int rand_shift[MAX_RES];
int rand_shift_init;
} NoiseContext;
#define OFFSET(x) offsetof(NoiseContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
#define NOISE_PARAMS(name, x, param) \
{#name"_seed", "set component #"#x" noise seed", OFFSET(param.seed), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, FLAGS}, \
{#name"_strength", "set component #"#x" strength", OFFSET(param.strength), AV_OPT_TYPE_INT, {.i64=0}, 0, 100, FLAGS}, \
{#name"s", "set component #"#x" strength", OFFSET(param.strength), AV_OPT_TYPE_INT, {.i64=0}, 0, 100, FLAGS}, \
{#name"_flags", "set component #"#x" flags", OFFSET(param.flags), AV_OPT_TYPE_FLAGS, {.i64=0}, 0, 31, FLAGS, #name"_flags"}, \
{#name"f", "set component #"#x" flags", OFFSET(param.flags), AV_OPT_TYPE_FLAGS, {.i64=0}, 0, 31, FLAGS, #name"_flags"}, \
{"a", "averaged noise", 0, AV_OPT_TYPE_CONST, {.i64=NOISE_AVERAGED}, 0, 0, FLAGS, #name"_flags"}, \
{"p", "(semi)regular pattern", 0, AV_OPT_TYPE_CONST, {.i64=NOISE_PATTERN}, 0, 0, FLAGS, #name"_flags"}, \
{"q", "high quality", 0, AV_OPT_TYPE_CONST, {.i64=NOISE_QUALITY}, 0, 0, FLAGS, #name"_flags"}, \
{"t", "temporal noise", 0, AV_OPT_TYPE_CONST, {.i64=NOISE_TEMPORAL}, 0, 0, FLAGS, #name"_flags"}, \
{"u", "uniform noise", 0, AV_OPT_TYPE_CONST, {.i64=NOISE_UNIFORM}, 0, 0, FLAGS, #name"_flags"},
static const AVOption noise_options[] = {
NOISE_PARAMS(all, 0, all)
NOISE_PARAMS(c0, 0, param[0])
NOISE_PARAMS(c1, 1, param[1])
NOISE_PARAMS(c2, 2, param[2])
NOISE_PARAMS(c3, 3, param[3])
{NULL}
};
AVFILTER_DEFINE_CLASS(noise);
static const int8_t patt[4] = { -1, 0, 1, 0 };
#define RAND_N(range) ((int) ((double) range * av_lfg_get(lfg) / (UINT_MAX + 1.0)))
static int init_noise(NoiseContext *n, int comp)
{
int8_t *noise = av_malloc(MAX_NOISE * sizeof(int8_t));
FilterParams *fp = &n->param[comp];
AVLFG *lfg = &n->param[comp].lfg;
int strength = fp->strength;
int flags = fp->flags;
int i, j;
if (!noise)
return AVERROR(ENOMEM);
av_lfg_init(&fp->lfg, fp->seed);
for (i = 0, j = 0; i < MAX_NOISE; i++, j++) {
if (flags & NOISE_UNIFORM) {
if (flags & NOISE_AVERAGED) {
if (flags & NOISE_PATTERN) {
noise[i] = (RAND_N(strength) - strength / 2) / 6
+ patt[j % 4] * strength * 0.25 / 3;
} else {
noise[i] = (RAND_N(strength) - strength / 2) / 3;
}
} else {
if (flags & NOISE_PATTERN) {
noise[i] = (RAND_N(strength) - strength / 2) / 2
+ patt[j % 4] * strength * 0.25;
} else {
noise[i] = RAND_N(strength) - strength / 2;
}
}
} else {
double x1, x2, w, y1;
do {
x1 = 2.0 * av_lfg_get(lfg) / (float)RAND_MAX - 1.0;
x2 = 2.0 * av_lfg_get(lfg) / (float)RAND_MAX - 1.0;
w = x1 * x1 + x2 * x2;
} while (w >= 1.0);
w = sqrt((-2.0 * log(w)) / w);
y1 = x1 * w;
y1 *= strength / sqrt(3.0);
if (flags & NOISE_PATTERN) {
y1 /= 2;
y1 += patt[j % 4] * strength * 0.35;
}
y1 = av_clipf(y1, -128, 127);
if (flags & NOISE_AVERAGED)
y1 /= 3.0;
noise[i] = (int)y1;
}
if (RAND_N(6) == 0)
j--;
}
for (i = 0; i < MAX_RES; i++)
for (j = 0; j < 3; j++)
fp->prev_shift[i][j] = noise + (av_lfg_get(lfg) & (MAX_SHIFT - 1));
if (!n->rand_shift_init) {
for (i = 0; i < MAX_RES; i++)
n->rand_shift[i] = av_lfg_get(lfg) & (MAX_SHIFT - 1);
n->rand_shift_init = 1;
}
fp->noise = noise;
fp->shiftptr = 0;
return 0;
}
static av_cold int init(AVFilterContext *ctx, const char *args)
{
NoiseContext *n = ctx->priv;
int ret, i;
n->class = &noise_class;
av_opt_set_defaults(n);
if ((ret = av_set_options_string(n, args, "=", ":")) < 0)
return ret;
for (i = 0; i < 4; i++) {
if (n->all.seed >= 0)
n->param[i].seed = n->all.seed;
else
n->param[i].seed = 123457;
if (n->all.strength)
n->param[i].strength = n->all.strength;
if (n->all.flags)
n->param[i].flags = n->all.flags;
}
for (i = 0; i < 4; i++) {
if (n->param[i].strength && ((ret = init_noise(n, i)) < 0))
return ret;
}
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
AVFilterFormats *formats = NULL;
int fmt;
for (fmt = 0; fmt < AV_PIX_FMT_NB; fmt++) {
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
if (desc->flags & PIX_FMT_PLANAR && !((desc->comp[0].depth_minus1 + 1) & 7))
ff_add_format(&formats, fmt);
}
ff_set_common_formats(ctx, formats);
return 0;
}
static int config_input(AVFilterLink *inlink)
{
NoiseContext *n = inlink->dst->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
int i, ret;
for (i = 0; i < desc->nb_components; i++)
n->nb_planes = FFMAX(n->nb_planes, desc->comp[i].plane);
n->nb_planes++;
if ((ret = av_image_fill_linesizes(n->linesize, inlink->format, inlink->w)) < 0)
return ret;
n->height[1] = n->height[2] = inlink->h >> desc->log2_chroma_h;
n->height[0] = n->height[3] = inlink->h;
return 0;
}
static void line_noise(uint8_t *dst, const uint8_t *src, int8_t *noise,
int len, int shift)
{
int i;
noise += shift;
for (i = 0; i < len; i++) {
int v = src[i] + noise[i];
dst[i] = av_clip_uint8(v);
}
}
static void line_noise_avg(uint8_t *dst, const uint8_t *src,
int len, int8_t **shift)
{
int i;
int8_t *src2 = (int8_t*)src;
for (i = 0; i < len; i++) {
const int n = shift[0][i] + shift[1][i] + shift[2][i];
dst[i] = src2[i] + ((n * src2[i]) >> 7);
}
}
static void noise(uint8_t *dst, const uint8_t *src,
int dst_linesize, int src_linesize,
int width, int height, NoiseContext *n, int comp)
{
int8_t *noise = n->param[comp].noise;
int flags = n->param[comp].flags;
AVLFG *lfg = &n->param[comp].lfg;
int shift, y;
if (!noise) {
if (dst != src) {
for (y = 0; y < height; y++) {
memcpy(dst, src, width);
dst += dst_linesize;
src += src_linesize;
}
}
return;
}
for (y = 0; y < height; y++) {
if (flags & NOISE_TEMPORAL)
shift = av_lfg_get(lfg) & (MAX_SHIFT - 1);
else
shift = n->rand_shift[y];
if (!(flags & NOISE_QUALITY))
shift &= ~7;
if (flags & NOISE_AVERAGED) {
line_noise_avg(dst, src, width, n->param[comp].prev_shift[y]);
n->param[comp].prev_shift[y][n->param[comp].shiftptr] = noise + shift;
} else {
line_noise(dst, src, noise, width, shift);
}
dst += dst_linesize;
src += src_linesize;
}
n->param[comp].shiftptr++;
if (n->param[comp].shiftptr == 3)
n->param[comp].shiftptr = 0;
}
static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
NoiseContext *n = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFilterBufferRef *out;
int ret, i;
if (inpicref->perms & AV_PERM_WRITE) {
out = inpicref;
} else {
out = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
if (!out) {
avfilter_unref_bufferp(&inpicref);
return AVERROR(ENOMEM);
}
avfilter_copy_buffer_ref_props(out, inpicref);
}
for (i = 0; i < n->nb_planes; i++)
noise(out->data[i], inpicref->data[i], out->linesize[i],
inpicref->linesize[i], n->linesize[i], n->height[i], n, i);
ret = ff_filter_frame(outlink, out);
if (inpicref != out)
avfilter_unref_buffer(inpicref);
return ret;
}
static av_cold void uninit(AVFilterContext *ctx)
{
NoiseContext *n = ctx->priv;
int i;
for (i = 0; i < 4; i++)
av_freep(&n->param[i].noise);
av_opt_free(n);
}
static const AVFilterPad noise_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer = ff_null_get_video_buffer,
.filter_frame = filter_frame,
.config_props = config_input,
.min_perms = AV_PERM_READ,
},
{ NULL }
};
static const AVFilterPad noise_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter avfilter_vf_noise = {
.name = "noise",
.description = NULL_IF_CONFIG_SMALL("Add noise."),
.priv_size = sizeof(NoiseContext),
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.inputs = noise_inputs,
.outputs = noise_outputs,
.priv_class = &noise_class,
};