/*
* Copyright (c) 2003 Michael Niedermayer
* Copyright (c) 2012 Jeremy Tran
*
* 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
* Apply a hue/saturation filter to the input video
* Ported from MPlayer libmpcodecs/vf_hue.c.
*/
#include <float.h>
#include "libavutil/eval.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#define SAT_MIN_VAL -10
#define SAT_MAX_VAL 10
static const char *const var_names[] = {
"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_N,
VAR_PTS,
VAR_R,
VAR_T,
VAR_TB,
VAR_NB
};
typedef struct HueContext {
const AVClass *class;
float hue_deg; /* hue expressed in degrees */
float hue; /* hue expressed in radians */
char *hue_deg_expr;
char *hue_expr;
AVExpr *hue_deg_pexpr;
AVExpr *hue_pexpr;
float saturation;
char *saturation_expr;
AVExpr *saturation_pexpr;
float brightness;
char *brightness_expr;
AVExpr *brightness_pexpr;
int hsub;
int vsub;
int is_first;
int32_t hue_sin;
int32_t hue_cos;
double var_values[VAR_NB];
uint8_t lut_l[256];
uint8_t lut_u[256][256];
uint8_t lut_v[256][256];
} HueContext;
#define OFFSET(x) offsetof(HueContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption hue_options[] = {
{ "h", "set the hue angle degrees expression", OFFSET(hue_deg_expr), AV_OPT_TYPE_STRING,
{ .str = NULL }, .flags = FLAGS },
{ "s", "set the saturation expression", OFFSET(saturation_expr), AV_OPT_TYPE_STRING,
{ .str = "1" }, .flags = FLAGS },
{ "H", "set the hue angle radians expression", OFFSET(hue_expr), AV_OPT_TYPE_STRING,
{ .str = NULL }, .flags = FLAGS },
{ "b", "set the brightness expression", OFFSET(brightness_expr), AV_OPT_TYPE_STRING,
{ .str = "0" }, .flags = FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(hue);
static inline void compute_sin_and_cos(HueContext *hue)
{
/*
* Scale the value to the norm of the resulting (U,V) vector, that is
* the saturation.
* This will be useful in the apply_lut function.
*/
hue->hue_sin = lrint(sin(hue->hue) * (1 << 16) * hue->saturation);
hue->hue_cos = lrint(cos(hue->hue) * (1 << 16) * hue->saturation);
}
static inline void create_luma_lut(HueContext *h)
{
const float b = h->brightness;
int i;
for (i = 0; i < 256; i++) {
h->lut_l[i] = av_clip_uint8(i + b * 25.5);
}
}
static inline void create_chrominance_lut(HueContext *h, const int32_t c,
const int32_t s)
{
int32_t i, j, u, v, new_u, new_v;
/*
* If we consider U and V as the components of a 2D vector then its angle
* is the hue and the norm is the saturation
*/
for (i = 0; i < 256; i++) {
for (j = 0; j < 256; j++) {
/* Normalize the components from range [16;140] to [-112;112] */
u = i - 128;
v = j - 128;
/*
* Apply the rotation of the vector : (c * u) - (s * v)
* (s * u) + (c * v)
* De-normalize the components (without forgetting to scale 128
* by << 16)
* Finally scale back the result by >> 16
*/
new_u = ((c * u) - (s * v) + (1 << 15) + (128 << 16)) >> 16;
new_v = ((s * u) + (c * v) + (1 << 15) + (128 << 16)) >> 16;
/* Prevent a potential overflow */
h->lut_u[i][j] = av_clip_uint8(new_u);
h->lut_v[i][j] = av_clip_uint8(new_v);
}
}
}
static int set_expr(AVExpr **pexpr_ptr, char **expr_ptr,
const char *expr, const char *option, void *log_ctx)
{
int ret;
AVExpr *new_pexpr;
char *new_expr;
new_expr = av_strdup(expr);
if (!new_expr)
return AVERROR(ENOMEM);
ret = av_expr_parse(&new_pexpr, expr, var_names,
NULL, NULL, NULL, NULL, 0, log_ctx);
if (ret < 0) {
av_log(log_ctx, AV_LOG_ERROR,
"Error when evaluating the expression '%s' for %s\n",
expr, option);
av_free(new_expr);
return ret;
}
if (*pexpr_ptr)
av_expr_free(*pexpr_ptr);
*pexpr_ptr = new_pexpr;
av_freep(expr_ptr);
*expr_ptr = new_expr;
return 0;
}
static av_cold int init(AVFilterContext *ctx)
{
HueContext *hue = ctx->priv;
int ret;
if (hue->hue_expr && hue->hue_deg_expr) {
av_log(ctx, AV_LOG_ERROR,
"H and h options are incompatible and cannot be specified "
"at the same time\n");
return AVERROR(EINVAL);
}
#define SET_EXPR(expr, option) \
if (hue->expr##_expr) do { \
ret = set_expr(&hue->expr##_pexpr, &hue->expr##_expr, \
hue->expr##_expr, option, ctx); \
if (ret < 0) \
return ret; \
} while (0)
SET_EXPR(brightness, "b");
SET_EXPR(saturation, "s");
SET_EXPR(hue_deg, "h");
SET_EXPR(hue, "H");
#undef SET_EXPR
av_log(ctx, AV_LOG_VERBOSE,
"H_expr:%s h_deg_expr:%s s_expr:%s b_expr:%s\n",
hue->hue_expr, hue->hue_deg_expr, hue->saturation_expr, hue->brightness_expr);
compute_sin_and_cos(hue);
hue->is_first = 1;
return 0;
}
static av_cold void uninit(AVFilterContext *ctx)
{
HueContext *hue = ctx->priv;
av_expr_free(hue->brightness_pexpr);
av_expr_free(hue->hue_deg_pexpr);
av_expr_free(hue->hue_pexpr);
av_expr_free(hue->saturation_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_YUVA444P, AV_PIX_FMT_YUVA422P,
AV_PIX_FMT_YUVA420P,
AV_PIX_FMT_NONE
};
AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
if (!fmts_list)
return AVERROR(ENOMEM);
return ff_set_common_formats(ctx, fmts_list);
}
static int config_props(AVFilterLink *inlink)
{
HueContext *hue = inlink->dst->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
hue->hsub = desc->log2_chroma_w;
hue->vsub = desc->log2_chroma_h;
hue->var_values[VAR_N] = 0;
hue->var_values[VAR_TB] = av_q2d(inlink->time_base);
hue->var_values[VAR_R] = inlink->frame_rate.num == 0 || inlink->frame_rate.den == 0 ?
NAN : av_q2d(inlink->frame_rate);
return 0;
}
static void apply_luma_lut(HueContext *s,
uint8_t *ldst, const int dst_linesize,
uint8_t *lsrc, const int src_linesize,
int w, int h)
{
int i;
while (h--) {
for (i = 0; i < w; i++)
ldst[i] = s->lut_l[lsrc[i]];
lsrc += src_linesize;
ldst += dst_linesize;
}
}
static void apply_lut(HueContext *s,
uint8_t *udst, uint8_t *vdst, const int dst_linesize,
uint8_t *usrc, uint8_t *vsrc, const int src_linesize,
int w, int h)
{
int i;
while (h--) {
for (i = 0; i < w; i++) {
const int u = usrc[i];
const int v = vsrc[i];
udst[i] = s->lut_u[u][v];
vdst[i] = s->lut_v[u][v];
}
usrc += src_linesize;
vsrc += src_linesize;
udst += dst_linesize;
vdst += dst_linesize;
}
}
#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 int filter_frame(AVFilterLink *inlink, AVFrame *inpic)
{
HueContext *hue = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFrame *outpic;
const int32_t old_hue_sin = hue->hue_sin, old_hue_cos = hue->hue_cos;
const float old_brightness = hue->brightness;
int direct = 0;
if (av_frame_is_writable(inpic)) {
direct = 1;
outpic = inpic;
} else {
outpic = ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!outpic) {
av_frame_free(&inpic);
return AVERROR(ENOMEM);
}
av_frame_copy_props(outpic, inpic);
}
hue->var_values[VAR_N] = inlink->frame_count_out;
hue->var_values[VAR_T] = TS2T(inpic->pts, inlink->time_base);
hue->var_values[VAR_PTS] = TS2D(inpic->pts);
if (hue->saturation_expr) {
hue->saturation = av_expr_eval(hue->saturation_pexpr, hue->var_values, NULL);
if (hue->saturation < SAT_MIN_VAL || hue->saturation > SAT_MAX_VAL) {
hue->saturation = av_clip(hue->saturation, SAT_MIN_VAL, SAT_MAX_VAL);
av_log(inlink->dst, AV_LOG_WARNING,
"Saturation value not in range [%d,%d]: clipping value to %0.1f\n",
SAT_MIN_VAL, SAT_MAX_VAL, hue->saturation);
}
}
if (hue->brightness_expr) {
hue->brightness = av_expr_eval(hue->brightness_pexpr, hue->var_values, NULL);
if (hue->brightness < -10 || hue->brightness > 10) {
hue->brightness = av_clipf(hue->brightness, -10, 10);
av_log(inlink->dst, AV_LOG_WARNING,
"Brightness value not in range [%d,%d]: clipping value to %0.1f\n",
-10, 10, hue->brightness);
}
}
if (hue->hue_deg_expr) {
hue->hue_deg = av_expr_eval(hue->hue_deg_pexpr, hue->var_values, NULL);
hue->hue = hue->hue_deg * M_PI / 180;
} else if (hue->hue_expr) {
hue->hue = av_expr_eval(hue->hue_pexpr, hue->var_values, NULL);
hue->hue_deg = hue->hue * 180 / M_PI;
}
av_log(inlink->dst, AV_LOG_DEBUG,
"H:%0.1f*PI h:%0.1f s:%0.1f b:%0.f t:%0.1f n:%d\n",
hue->hue/M_PI, hue->hue_deg, hue->saturation, hue->brightness,
hue->var_values[VAR_T], (int)hue->var_values[VAR_N]);
compute_sin_and_cos(hue);
if (hue->is_first || (old_hue_sin != hue->hue_sin || old_hue_cos != hue->hue_cos))
create_chrominance_lut(hue, hue->hue_cos, hue->hue_sin);
if (hue->is_first || (old_brightness != hue->brightness && hue->brightness))
create_luma_lut(hue);
if (!direct) {
if (!hue->brightness)
av_image_copy_plane(outpic->data[0], outpic->linesize[0],
inpic->data[0], inpic->linesize[0],
inlink->w, inlink->h);
if (inpic->data[3])
av_image_copy_plane(outpic->data[3], outpic->linesize[3],
inpic->data[3], inpic->linesize[3],
inlink->w, inlink->h);
}
apply_lut(hue, outpic->data[1], outpic->data[2], outpic->linesize[1],
inpic->data[1], inpic->data[2], inpic->linesize[1],
AV_CEIL_RSHIFT(inlink->w, hue->hsub),
AV_CEIL_RSHIFT(inlink->h, hue->vsub));
if (hue->brightness)
apply_luma_lut(hue, outpic->data[0], outpic->linesize[0],
inpic->data[0], inpic->linesize[0], inlink->w, inlink->h);
if (!direct)
av_frame_free(&inpic);
hue->is_first = 0;
return ff_filter_frame(outlink, outpic);
}
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
char *res, int res_len, int flags)
{
HueContext *hue = ctx->priv;
int ret;
#define SET_EXPR(expr, option) \
do { \
ret = set_expr(&hue->expr##_pexpr, &hue->expr##_expr, \
args, option, ctx); \
if (ret < 0) \
return ret; \
} while (0)
if (!strcmp(cmd, "h")) {
SET_EXPR(hue_deg, "h");
av_freep(&hue->hue_expr);
} else if (!strcmp(cmd, "H")) {
SET_EXPR(hue, "H");
av_freep(&hue->hue_deg_expr);
} else if (!strcmp(cmd, "s")) {
SET_EXPR(saturation, "s");
} else if (!strcmp(cmd, "b")) {
SET_EXPR(brightness, "b");
} else
return AVERROR(ENOSYS);
return 0;
}
static const AVFilterPad hue_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_props,
},
{ NULL }
};
static const AVFilterPad hue_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter ff_vf_hue = {
.name = "hue",
.description = NULL_IF_CONFIG_SMALL("Adjust the hue and saturation of the input video."),
.priv_size = sizeof(HueContext),
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.process_command = process_command,
.inputs = hue_inputs,
.outputs = hue_outputs,
.priv_class = &hue_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};