/*
* Copyright (c) 2015 Arwa Arif <arwaarif1994@gmail.com>
*
* 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
* FFT domain filtering.
*/
#include "libavfilter/internal.h"
#include "libavutil/common.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "libavcodec/avfft.h"
#include "libavutil/eval.h"
#define MAX_PLANES 4
typedef struct {
const AVClass *class;
RDFTContext *rdft;
int rdft_hbits[MAX_PLANES];
int rdft_vbits[MAX_PLANES];
size_t rdft_hlen[MAX_PLANES];
size_t rdft_vlen[MAX_PLANES];
FFTSample *rdft_hdata[MAX_PLANES];
FFTSample *rdft_vdata[MAX_PLANES];
int dc[MAX_PLANES];
char *weight_str[MAX_PLANES];
AVExpr *weight_expr[MAX_PLANES];
double *weight[MAX_PLANES];
} FFTFILTContext;
static const char *const var_names[] = { "X", "Y", "W", "H", NULL };
enum { VAR_X, VAR_Y, VAR_W, VAR_H, VAR_VARS_NB };
enum { Y = 0, U, V };
#define OFFSET(x) offsetof(FFTFILTContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption fftfilt_options[] = {
{ "dc_Y", "adjust gain in Y plane", OFFSET(dc[Y]), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1000, FLAGS },
{ "dc_U", "adjust gain in U plane", OFFSET(dc[U]), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1000, FLAGS },
{ "dc_V", "adjust gain in V plane", OFFSET(dc[V]), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1000, FLAGS },
{ "weight_Y", "set luminance expression in Y plane", OFFSET(weight_str[Y]), AV_OPT_TYPE_STRING, {.str = "1"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "weight_U", "set chrominance expression in U plane", OFFSET(weight_str[U]), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "weight_V", "set chrominance expression in V plane", OFFSET(weight_str[V]), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
{NULL},
};
AVFILTER_DEFINE_CLASS(fftfilt);
static inline double lum(void *priv, double x, double y, int plane)
{
FFTFILTContext *fftfilt = priv;
return fftfilt->rdft_vdata[plane][(int)x * fftfilt->rdft_vlen[plane] + (int)y];
}
static double weight_Y(void *priv, double x, double y) { return lum(priv, x, y, Y); }
static double weight_U(void *priv, double x, double y) { return lum(priv, x, y, U); }
static double weight_V(void *priv, double x, double y) { return lum(priv, x, y, V); }
static void copy_rev (FFTSample *dest, int w, int w2)
{
int i;
for (i = w; i < w + (w2-w)/2; i++)
dest[i] = dest[2*w - i - 1];
for (; i < w2; i++)
dest[i] = dest[w2 - i];
}
/*Horizontal pass - RDFT*/
static void rdft_horizontal(FFTFILTContext *fftfilt, AVFrame *in, int w, int h, int plane)
{
int i, j;
fftfilt->rdft = av_rdft_init(fftfilt->rdft_hbits[plane], DFT_R2C);
for (i = 0; i < h; i++) {
for (j = 0; j < w; j++)
fftfilt->rdft_hdata[plane][i * fftfilt->rdft_hlen[plane] + j] = *(in->data[plane] + in->linesize[plane] * i + j);
copy_rev(fftfilt->rdft_hdata[plane] + i * fftfilt->rdft_hlen[plane], w, fftfilt->rdft_hlen[plane]);
}
for (i = 0; i < h; i++)
av_rdft_calc(fftfilt->rdft, fftfilt->rdft_hdata[plane] + i * fftfilt->rdft_hlen[plane]);
av_rdft_end(fftfilt->rdft);
}
/*Vertical pass - RDFT*/
static void rdft_vertical(FFTFILTContext *fftfilt, int h, int plane)
{
int i, j;
fftfilt->rdft = av_rdft_init(fftfilt->rdft_vbits[plane], DFT_R2C);
for (i = 0; i < fftfilt->rdft_hlen[plane]; i++) {
for (j = 0; j < h; j++)
fftfilt->rdft_vdata[plane][i * fftfilt->rdft_vlen[plane] + j] =
fftfilt->rdft_hdata[plane][j * fftfilt->rdft_hlen[plane] + i];
copy_rev(fftfilt->rdft_vdata[plane] + i * fftfilt->rdft_vlen[plane], h, fftfilt->rdft_vlen[plane]);
}
for (i = 0; i < fftfilt->rdft_hlen[plane]; i++)
av_rdft_calc(fftfilt->rdft, fftfilt->rdft_vdata[plane] + i * fftfilt->rdft_vlen[plane]);
av_rdft_end(fftfilt->rdft);
}
/*Vertical pass - IRDFT*/
static void irdft_vertical(FFTFILTContext *fftfilt, int h, int plane)
{
int i, j;
fftfilt->rdft = av_rdft_init(fftfilt->rdft_vbits[plane], IDFT_C2R);
for (i = 0; i < fftfilt->rdft_hlen[plane]; i++)
av_rdft_calc(fftfilt->rdft, fftfilt->rdft_vdata[plane] + i * fftfilt->rdft_vlen[plane]);
for (i = 0; i < fftfilt->rdft_hlen[plane]; i++)
for (j = 0; j < h; j++)
fftfilt->rdft_hdata[plane][j * fftfilt->rdft_hlen[plane] + i] =
fftfilt->rdft_vdata[plane][i * fftfilt->rdft_vlen[plane] + j];
av_rdft_end(fftfilt->rdft);
}
/*Horizontal pass - IRDFT*/
static void irdft_horizontal(FFTFILTContext *fftfilt, AVFrame *out, int w, int h, int plane)
{
int i, j;
fftfilt->rdft = av_rdft_init(fftfilt->rdft_hbits[plane], IDFT_C2R);
for (i = 0; i < h; i++)
av_rdft_calc(fftfilt->rdft, fftfilt->rdft_hdata[plane] + i * fftfilt->rdft_hlen[plane]);
for (i = 0; i < h; i++)
for (j = 0; j < w; j++)
*(out->data[plane] + out->linesize[plane] * i + j) = av_clip(fftfilt->rdft_hdata[plane][i
*fftfilt->rdft_hlen[plane] + j] * 4 /
(fftfilt->rdft_hlen[plane] *
fftfilt->rdft_vlen[plane]), 0, 255);
av_rdft_end(fftfilt->rdft);
}
static av_cold int initialize(AVFilterContext *ctx)
{
FFTFILTContext *fftfilt = ctx->priv;
int ret = 0, plane;
if (!fftfilt->dc[U] && !fftfilt->dc[V]) {
fftfilt->dc[U] = fftfilt->dc[Y];
fftfilt->dc[V] = fftfilt->dc[Y];
} else {
if (!fftfilt->dc[U]) fftfilt->dc[U] = fftfilt->dc[V];
if (!fftfilt->dc[V]) fftfilt->dc[V] = fftfilt->dc[U];
}
if (!fftfilt->weight_str[U] && !fftfilt->weight_str[V]) {
fftfilt->weight_str[U] = av_strdup(fftfilt->weight_str[Y]);
fftfilt->weight_str[V] = av_strdup(fftfilt->weight_str[Y]);
} else {
if (!fftfilt->weight_str[U]) fftfilt->weight_str[U] = av_strdup(fftfilt->weight_str[V]);
if (!fftfilt->weight_str[V]) fftfilt->weight_str[V] = av_strdup(fftfilt->weight_str[U]);
}
for (plane = 0; plane < 3; plane++) {
static double (*p[])(void *, double, double) = { weight_Y, weight_U, weight_V };
const char *const func2_names[] = {"weight_Y", "weight_U", "weight_V", NULL };
double (*func2[])(void *, double, double) = { weight_Y, weight_U, weight_V, p[plane], NULL };
ret = av_expr_parse(&fftfilt->weight_expr[plane], fftfilt->weight_str[plane], var_names,
NULL, NULL, func2_names, func2, 0, ctx);
if (ret < 0)
break;
}
return ret;
}
static int config_props(AVFilterLink *inlink)
{
FFTFILTContext *fftfilt = inlink->dst->priv;
const AVPixFmtDescriptor *desc;
int rdft_hbits, rdft_vbits, i, j, plane;
double values[VAR_VARS_NB];
desc = av_pix_fmt_desc_get(inlink->format);
for (i = 0; i < desc->nb_components; i++) {
int w = inlink->w;
int h = inlink->h;
/* RDFT - Array initialization for Horizontal pass*/
for (rdft_hbits = 1; 1 << rdft_hbits < w*10/9; rdft_hbits++);
fftfilt->rdft_hbits[i] = rdft_hbits;
fftfilt->rdft_hlen[i] = 1 << rdft_hbits;
if (!(fftfilt->rdft_hdata[i] = av_malloc_array(h, fftfilt->rdft_hlen[i] * sizeof(FFTSample))))
return AVERROR(ENOMEM);
/* RDFT - Array initialization for Vertical pass*/
for (rdft_vbits = 1; 1 << rdft_vbits < h*10/9; rdft_vbits++);
fftfilt->rdft_vbits[i] = rdft_vbits;
fftfilt->rdft_vlen[i] = 1 << rdft_vbits;
if (!(fftfilt->rdft_vdata[i] = av_malloc_array(fftfilt->rdft_hlen[i], fftfilt->rdft_vlen[i] * sizeof(FFTSample))))
return AVERROR(ENOMEM);
}
/*Luminance value - Array initialization*/
values[VAR_W] = inlink->w;
values[VAR_H] = inlink->h;
for (plane = 0; plane < 3; plane++)
{
if(!(fftfilt->weight[plane] = av_malloc_array(fftfilt->rdft_hlen[plane], fftfilt->rdft_vlen[plane] * sizeof(double))))
return AVERROR(ENOMEM);
for (i = 0; i < fftfilt->rdft_hlen[plane]; i++)
{
values[VAR_X] = i;
for (j = 0; j < fftfilt->rdft_vlen[plane]; j++)
{
values[VAR_Y] = j;
fftfilt->weight[plane][i * fftfilt->rdft_vlen[plane] + j] =
av_expr_eval(fftfilt->weight_expr[plane], values, fftfilt);
}
}
}
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = inlink->dst->outputs[0];
const AVPixFmtDescriptor *desc;
FFTFILTContext *fftfilt = ctx->priv;
AVFrame *out;
int i, j, plane;
out = ff_get_video_buffer(outlink, inlink->w, inlink->h);
if (!out)
return AVERROR(ENOMEM);
av_frame_copy_props(out, in);
desc = av_pix_fmt_desc_get(inlink->format);
for (plane = 0; plane < desc->nb_components; plane++) {
int w = inlink->w;
int h = inlink->h;
if (plane == 1 || plane == 2) {
w = FF_CEIL_RSHIFT(w, desc->log2_chroma_w);
h = FF_CEIL_RSHIFT(h, desc->log2_chroma_h);
}
rdft_horizontal(fftfilt, in, w, h, plane);
rdft_vertical(fftfilt, h, plane);
/*Change user defined parameters*/
for (i = 0; i < fftfilt->rdft_hlen[plane]; i++)
for (j = 0; j < fftfilt->rdft_vlen[plane]; j++)
fftfilt->rdft_vdata[plane][i * fftfilt->rdft_vlen[plane] + j] *=
fftfilt->weight[plane][i * fftfilt->rdft_vlen[plane] + j];
fftfilt->rdft_vdata[plane][0] += fftfilt->rdft_hlen[plane] * fftfilt->rdft_vlen[plane] * fftfilt->dc[plane];
irdft_vertical(fftfilt, h, plane);
irdft_horizontal(fftfilt, out, w, h, plane);
}
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static av_cold void uninit(AVFilterContext *ctx)
{
FFTFILTContext *fftfilt = ctx->priv;
int i;
for (i = 0; i < MAX_PLANES; i++) {
av_free(fftfilt->rdft_hdata[i]);
av_free(fftfilt->rdft_vdata[i]);
av_expr_free(fftfilt->weight_expr[i]);
av_free(fftfilt->weight[i]);
}
}
static int query_formats(AVFilterContext *ctx)
{
static const enum AVPixelFormat pixel_fmts_fftfilt[] = {
AV_PIX_FMT_GRAY8,
AV_PIX_FMT_YUV444P,
AV_PIX_FMT_NONE
};
AVFilterFormats *fmts_list = ff_make_format_list(pixel_fmts_fftfilt);
if (!fmts_list)
return AVERROR(ENOMEM);
return ff_set_common_formats(ctx, fmts_list);
}
static const AVFilterPad fftfilt_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_props,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad fftfilt_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter ff_vf_fftfilt = {
.name = "fftfilt",
.description = NULL_IF_CONFIG_SMALL("Apply arbitrary expressions to samples in frequency domain"),
.priv_size = sizeof(FFTFILTContext),
.priv_class = &fftfilt_class,
.inputs = fftfilt_inputs,
.outputs = fftfilt_outputs,
.query_formats = query_formats,
.init = initialize,
.uninit = uninit,
};