/*
* 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 "libavutil/opt.h"
#include "libavutil/bprint.h"
#include "libavutil/eval.h"
#include "libavutil/file.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/avassert.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "drawutils.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#define R 0
#define G 1
#define B 2
#define A 3
struct keypoint {
double x, y;
struct keypoint *next;
};
#define NB_COMP 3
enum preset {
PRESET_NONE,
PRESET_COLOR_NEGATIVE,
PRESET_CROSS_PROCESS,
PRESET_DARKER,
PRESET_INCREASE_CONTRAST,
PRESET_LIGHTER,
PRESET_LINEAR_CONTRAST,
PRESET_MEDIUM_CONTRAST,
PRESET_NEGATIVE,
PRESET_STRONG_CONTRAST,
PRESET_VINTAGE,
NB_PRESETS,
};
typedef struct {
const AVClass *class;
enum preset preset;
char *comp_points_str[NB_COMP + 1];
char *comp_points_str_all;
uint8_t graph[NB_COMP + 1][256];
char *psfile;
uint8_t rgba_map[4];
int step;
} CurvesContext;
#define OFFSET(x) offsetof(CurvesContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption curves_options[] = {
{ "preset", "select a color curves preset", OFFSET(preset), AV_OPT_TYPE_INT, {.i64=PRESET_NONE}, PRESET_NONE, NB_PRESETS-1, FLAGS, "preset_name" },
{ "none", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_NONE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "color_negative", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_COLOR_NEGATIVE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "cross_process", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_CROSS_PROCESS}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "darker", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_DARKER}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "increase_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_INCREASE_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "lighter", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_LIGHTER}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "linear_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_LINEAR_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "medium_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_MEDIUM_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "negative", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_NEGATIVE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "strong_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_STRONG_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "vintage", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_VINTAGE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
{ "master","set master points coordinates",OFFSET(comp_points_str[NB_COMP]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "m", "set master points coordinates",OFFSET(comp_points_str[NB_COMP]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "red", "set red points coordinates", OFFSET(comp_points_str[0]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "r", "set red points coordinates", OFFSET(comp_points_str[0]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "green", "set green points coordinates", OFFSET(comp_points_str[1]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "g", "set green points coordinates", OFFSET(comp_points_str[1]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "blue", "set blue points coordinates", OFFSET(comp_points_str[2]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "b", "set blue points coordinates", OFFSET(comp_points_str[2]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "all", "set points coordinates for all components", OFFSET(comp_points_str_all), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ "psfile", "set Photoshop curves file name", OFFSET(psfile), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(curves);
static const struct {
const char *r;
const char *g;
const char *b;
const char *master;
} curves_presets[] = {
[PRESET_COLOR_NEGATIVE] = {
"0/1 0.129/1 0.466/0.498 0.725/0 1/0",
"0/1 0.109/1 0.301/0.498 0.517/0 1/0",
"0/1 0.098/1 0.235/0.498 0.423/0 1/0",
},
[PRESET_CROSS_PROCESS] = {
"0.25/0.156 0.501/0.501 0.686/0.745",
"0.25/0.188 0.38/0.501 0.745/0.815 1/0.815",
"0.231/0.094 0.709/0.874",
},
[PRESET_DARKER] = { .master = "0.5/0.4" },
[PRESET_INCREASE_CONTRAST] = { .master = "0.149/0.066 0.831/0.905 0.905/0.98" },
[PRESET_LIGHTER] = { .master = "0.4/0.5" },
[PRESET_LINEAR_CONTRAST] = { .master = "0.305/0.286 0.694/0.713" },
[PRESET_MEDIUM_CONTRAST] = { .master = "0.286/0.219 0.639/0.643" },
[PRESET_NEGATIVE] = { .master = "0/1 1/0" },
[PRESET_STRONG_CONTRAST] = { .master = "0.301/0.196 0.592/0.6 0.686/0.737" },
[PRESET_VINTAGE] = {
"0/0.11 0.42/0.51 1/0.95",
"0.50/0.48",
"0/0.22 0.49/0.44 1/0.8",
}
};
static struct keypoint *make_point(double x, double y, struct keypoint *next)
{
struct keypoint *point = av_mallocz(sizeof(*point));
if (!point)
return NULL;
point->x = x;
point->y = y;
point->next = next;
return point;
}
static int parse_points_str(AVFilterContext *ctx, struct keypoint **points, const char *s)
{
char *p = (char *)s; // strtod won't alter the string
struct keypoint *last = NULL;
/* construct a linked list based on the key points string */
while (p && *p) {
struct keypoint *point = make_point(0, 0, NULL);
if (!point)
return AVERROR(ENOMEM);
point->x = av_strtod(p, &p); if (p && *p) p++;
point->y = av_strtod(p, &p); if (p && *p) p++;
if (point->x < 0 || point->x > 1 || point->y < 0 || point->y > 1) {
av_log(ctx, AV_LOG_ERROR, "Invalid key point coordinates (%f;%f), "
"x and y must be in the [0;1] range.\n", point->x, point->y);
return AVERROR(EINVAL);
}
if (!*points)
*points = point;
if (last) {
if ((int)(last->x * 255) >= (int)(point->x * 255)) {
av_log(ctx, AV_LOG_ERROR, "Key point coordinates (%f;%f) "
"and (%f;%f) are too close from each other or not "
"strictly increasing on the x-axis\n",
last->x, last->y, point->x, point->y);
return AVERROR(EINVAL);
}
last->next = point;
}
last = point;
}
/* auto insert first key point if missing at x=0 */
if (!*points) {
last = make_point(0, 0, NULL);
if (!last)
return AVERROR(ENOMEM);
last->x = last->y = 0;
*points = last;
} else if ((*points)->x != 0.) {
struct keypoint *newfirst = make_point(0, 0, *points);
if (!newfirst)
return AVERROR(ENOMEM);
*points = newfirst;
}
av_assert0(last);
/* auto insert last key point if missing at x=1 */
if (last->x != 1.) {
struct keypoint *point = make_point(1, 1, NULL);
if (!point)
return AVERROR(ENOMEM);
last->next = point;
}
return 0;
}
static int get_nb_points(const struct keypoint *d)
{
int n = 0;
while (d) {
n++;
d = d->next;
}
return n;
}
/**
* Natural cubic spline interpolation
* Finding curves using Cubic Splines notes by Steven Rauch and John Stockie.
* @see http://people.math.sfu.ca/~stockie/teaching/macm316/notes/splines.pdf
*/
static int interpolate(AVFilterContext *ctx, uint8_t *y, const struct keypoint *points)
{
int i, ret = 0;
const struct keypoint *point;
double xprev = 0;
int n = get_nb_points(points); // number of splines
double (*matrix)[3] = av_calloc(n, sizeof(*matrix));
double *h = av_malloc((n - 1) * sizeof(*h));
double *r = av_calloc(n, sizeof(*r));
if (!matrix || !h || !r) {
ret = AVERROR(ENOMEM);
goto end;
}
/* h(i) = x(i+1) - x(i) */
i = -1;
for (point = points; point; point = point->next) {
if (i != -1)
h[i] = point->x - xprev;
xprev = point->x;
i++;
}
/* right-side of the polynomials, will be modified to contains the solution */
point = points;
for (i = 1; i < n - 1; i++) {
double yp = point->y,
yc = point->next->y,
yn = point->next->next->y;
r[i] = 6 * ((yn-yc)/h[i] - (yc-yp)/h[i-1]);
point = point->next;
}
#define BD 0 /* sub diagonal (below main) */
#define MD 1 /* main diagonal (center) */
#define AD 2 /* sup diagonal (above main) */
/* left side of the polynomials into a tridiagonal matrix. */
matrix[0][MD] = matrix[n - 1][MD] = 1;
for (i = 1; i < n - 1; i++) {
matrix[i][BD] = h[i-1];
matrix[i][MD] = 2 * (h[i-1] + h[i]);
matrix[i][AD] = h[i];
}
/* tridiagonal solving of the linear system */
for (i = 1; i < n; i++) {
double den = matrix[i][MD] - matrix[i][BD] * matrix[i-1][AD];
double k = den ? 1./den : 1.;
matrix[i][AD] *= k;
r[i] = (r[i] - matrix[i][BD] * r[i - 1]) * k;
}
for (i = n - 2; i >= 0; i--)
r[i] = r[i] - matrix[i][AD] * r[i + 1];
/* compute the graph with x=[0..255] */
i = 0;
point = points;
av_assert0(point->next); // always at least 2 key points
while (point->next) {
double yc = point->y;
double yn = point->next->y;
double a = yc;
double b = (yn-yc)/h[i] - h[i]*r[i]/2. - h[i]*(r[i+1]-r[i])/6.;
double c = r[i] / 2.;
double d = (r[i+1] - r[i]) / (6.*h[i]);
int x;
int x_start = point->x * 255;
int x_end = point->next->x * 255;
av_assert0(x_start >= 0 && x_start <= 255 &&
x_end >= 0 && x_end <= 255);
for (x = x_start; x <= x_end; x++) {
double xx = (x - x_start) * 1/255.;
double yy = a + b*xx + c*xx*xx + d*xx*xx*xx;
y[x] = av_clipf(yy, 0, 1) * 255;
av_log(ctx, AV_LOG_DEBUG, "f(%f)=%f -> y[%d]=%d\n", xx, yy, x, y[x]);
}
point = point->next;
i++;
}
end:
av_free(matrix);
av_free(h);
av_free(r);
return ret;
}
static int parse_psfile(AVFilterContext *ctx, const char *fname)
{
CurvesContext *curves = ctx->priv;
uint8_t *buf;
size_t size;
int i, ret, av_unused(version), nb_curves;
AVBPrint ptstr;
static const int comp_ids[] = {3, 0, 1, 2};
av_bprint_init(&ptstr, 0, AV_BPRINT_SIZE_AUTOMATIC);
ret = av_file_map(fname, &buf, &size, 0, NULL);
if (ret < 0)
return ret;
#define READ16(dst) do { \
if (size < 2) \
return AVERROR_INVALIDDATA; \
dst = AV_RB16(buf); \
buf += 2; \
size -= 2; \
} while (0)
READ16(version);
READ16(nb_curves);
for (i = 0; i < FFMIN(nb_curves, FF_ARRAY_ELEMS(comp_ids)); i++) {
int nb_points, n;
av_bprint_clear(&ptstr);
READ16(nb_points);
for (n = 0; n < nb_points; n++) {
int y, x;
READ16(y);
READ16(x);
av_bprintf(&ptstr, "%f/%f ", x / 255., y / 255.);
}
if (*ptstr.str) {
char **pts = &curves->comp_points_str[comp_ids[i]];
if (!*pts) {
*pts = av_strdup(ptstr.str);
av_log(ctx, AV_LOG_DEBUG, "curves %d (intid=%d) [%d points]: [%s]\n",
i, comp_ids[i], nb_points, *pts);
if (!*pts) {
ret = AVERROR(ENOMEM);
goto end;
}
}
}
}
end:
av_bprint_finalize(&ptstr, NULL);
av_file_unmap(buf, size);
return ret;
}
static av_cold int init(AVFilterContext *ctx)
{
int i, j, ret;
CurvesContext *curves = ctx->priv;
struct keypoint *comp_points[NB_COMP + 1] = {0};
char **pts = curves->comp_points_str;
const char *allp = curves->comp_points_str_all;
//if (!allp && curves->preset != PRESET_NONE && curves_presets[curves->preset].all)
// allp = curves_presets[curves->preset].all;
if (allp) {
for (i = 0; i < NB_COMP; i++) {
if (!pts[i])
pts[i] = av_strdup(allp);
if (!pts[i])
return AVERROR(ENOMEM);
}
}
if (curves->psfile) {
ret = parse_psfile(ctx, curves->psfile);
if (ret < 0)
return ret;
}
if (curves->preset != PRESET_NONE) {
#define SET_COMP_IF_NOT_SET(n, name) do { \
if (!pts[n] && curves_presets[curves->preset].name) { \
pts[n] = av_strdup(curves_presets[curves->preset].name); \
if (!pts[n]) \
return AVERROR(ENOMEM); \
} \
} while (0)
SET_COMP_IF_NOT_SET(0, r);
SET_COMP_IF_NOT_SET(1, g);
SET_COMP_IF_NOT_SET(2, b);
SET_COMP_IF_NOT_SET(3, master);
}
for (i = 0; i < NB_COMP + 1; i++) {
ret = parse_points_str(ctx, comp_points + i, curves->comp_points_str[i]);
if (ret < 0)
return ret;
ret = interpolate(ctx, curves->graph[i], comp_points[i]);
if (ret < 0)
return ret;
}
if (pts[NB_COMP]) {
for (i = 0; i < NB_COMP; i++)
for (j = 0; j < 256; j++)
curves->graph[i][j] = curves->graph[NB_COMP][curves->graph[i][j]];
}
if (av_log_get_level() >= AV_LOG_VERBOSE) {
for (i = 0; i < NB_COMP; i++) {
struct keypoint *point = comp_points[i];
av_log(ctx, AV_LOG_VERBOSE, "#%d points:", i);
while (point) {
av_log(ctx, AV_LOG_VERBOSE, " (%f;%f)", point->x, point->y);
point = point->next;
}
av_log(ctx, AV_LOG_VERBOSE, "\n");
av_log(ctx, AV_LOG_VERBOSE, "#%d values:", i);
for (j = 0; j < 256; j++)
av_log(ctx, AV_LOG_VERBOSE, " %02X", curves->graph[i][j]);
av_log(ctx, AV_LOG_VERBOSE, "\n");
}
}
for (i = 0; i < NB_COMP + 1; i++) {
struct keypoint *point = comp_points[i];
while (point) {
struct keypoint *next = point->next;
av_free(point);
point = next;
}
}
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
static const enum AVPixelFormat pix_fmts[] = {
AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA,
AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR,
AV_PIX_FMT_0RGB, AV_PIX_FMT_0BGR,
AV_PIX_FMT_RGB0, AV_PIX_FMT_BGR0,
AV_PIX_FMT_NONE
};
ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
return 0;
}
static int config_input(AVFilterLink *inlink)
{
CurvesContext *curves = inlink->dst->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
ff_fill_rgba_map(curves->rgba_map, inlink->format);
curves->step = av_get_padded_bits_per_pixel(desc) >> 3;
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
int x, y, direct = 0;
AVFilterContext *ctx = inlink->dst;
CurvesContext *curves = ctx->priv;
AVFilterLink *outlink = ctx->outputs[0];
AVFrame *out;
uint8_t *dst;
const uint8_t *src;
const int step = curves->step;
const uint8_t r = curves->rgba_map[R];
const uint8_t g = curves->rgba_map[G];
const uint8_t b = curves->rgba_map[B];
const uint8_t a = curves->rgba_map[A];
if (av_frame_is_writable(in)) {
direct = 1;
out = in;
} else {
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);
}
dst = out->data[0];
src = in ->data[0];
for (y = 0; y < inlink->h; y++) {
for (x = 0; x < inlink->w * step; x += step) {
dst[x + r] = curves->graph[R][src[x + r]];
dst[x + g] = curves->graph[G][src[x + g]];
dst[x + b] = curves->graph[B][src[x + b]];
if (!direct && step == 4)
dst[x + a] = src[x + a];
}
dst += out->linesize[0];
src += in ->linesize[0];
}
if (!direct)
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static const AVFilterPad curves_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_input,
},
{ NULL }
};
static const AVFilterPad curves_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter avfilter_vf_curves = {
.name = "curves",
.description = NULL_IF_CONFIG_SMALL("Adjust components curves."),
.priv_size = sizeof(CurvesContext),
.init = init,
.query_formats = query_formats,
.inputs = curves_inputs,
.outputs = curves_outputs,
.priv_class = &curves_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};