/*
* Original MPlayer filters by Richard Felker, Hampa Hug, Daniel Moreno,
* and Michael Niedermeyer.
*
* Copyright (c) 2014 James Darnley <james.darnley@gmail.com>
* 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 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
* very simple video equalizer
*/
#include "libavfilter/internal.h"
#include "libavutil/common.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "vf_eq.h"
static void create_lut(EQParameters *param)
{
int i;
double g = 1.0 / param->gamma;
double lw = 1.0 - param->gamma_weight;
for (i = 0; i < 256; i++) {
double v = i / 255.0;
v = param->contrast * (v - 0.5) + 0.5 + param->brightness;
if (v <= 0.0) {
param->lut[i] = 0;
} else {
v = v * lw + pow(v, g) * param->gamma_weight;
if (v >= 1.0)
param->lut[i] = 255;
else
param->lut[i] = 256.0 * v;
}
}
param->lut_clean = 1;
}
static void apply_lut(EQParameters *param, uint8_t *dst, int dst_stride,
const uint8_t *src, int src_stride, int w, int h)
{
int x, y;
if (!param->lut_clean)
create_lut(param);
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
dst[y * dst_stride + x] = param->lut[src[y * src_stride + x]];
}
}
}
static void process_c(EQParameters *param, uint8_t *dst, int dst_stride,
const uint8_t *src, int src_stride, int w, int h)
{
int x, y, pel;
int contrast = (int) (param->contrast * 256 * 16);
int brightness = ((int) (100.0 * param->brightness + 100.0) * 511) / 200 - 128 - contrast / 32;
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
pel = ((src[y * src_stride + x] * contrast) >> 12) + brightness;
if (pel & ~255)
pel = (-pel) >> 31;
dst[y * dst_stride + x] = pel;
}
}
}
static void check_values(EQParameters *param, EQContext *eq)
{
if (param->contrast == 1.0 && param->brightness == 0.0 && param->gamma == 1.0)
param->adjust = NULL;
else if (param->gamma == 1.0 && fabs(param->contrast) < 7.9)
param->adjust = eq->process;
else
param->adjust = apply_lut;
}
static void set_contrast(EQContext *eq)
{
eq->contrast = av_clipf(av_expr_eval(eq->contrast_pexpr, eq->var_values, eq), -1000.0, 1000.0);
eq->param[0].contrast = eq->contrast;
eq->param[0].lut_clean = 0;
check_values(&eq->param[0], eq);
}
static void set_brightness(EQContext *eq)
{
eq->brightness = av_clipf(av_expr_eval(eq->brightness_pexpr, eq->var_values, eq), -1.0, 1.0);
eq->param[0].brightness = eq->brightness;
eq->param[0].lut_clean = 0;
check_values(&eq->param[0], eq);
}
static void set_gamma(EQContext *eq)
{
int i;
eq->gamma = av_clipf(av_expr_eval(eq->gamma_pexpr, eq->var_values, eq), 0.1, 10.0);
eq->gamma_r = av_clipf(av_expr_eval(eq->gamma_r_pexpr, eq->var_values, eq), 0.1, 10.0);
eq->gamma_g = av_clipf(av_expr_eval(eq->gamma_g_pexpr, eq->var_values, eq), 0.1, 10.0);
eq->gamma_b = av_clipf(av_expr_eval(eq->gamma_b_pexpr, eq->var_values, eq), 0.1, 10.0);
eq->gamma_weight = av_clipf(av_expr_eval(eq->gamma_weight_pexpr, eq->var_values, eq), 0.0, 1.0);
eq->param[0].gamma = eq->gamma * eq->gamma_g;
eq->param[1].gamma = sqrt(eq->gamma_b / eq->gamma_g);
eq->param[2].gamma = sqrt(eq->gamma_r / eq->gamma_g);
for (i = 0; i < 3; i++) {
eq->param[i].gamma_weight = eq->gamma_weight;
eq->param[i].lut_clean = 0;
check_values(&eq->param[i], eq);
}
}
static void set_saturation(EQContext *eq)
{
int i;
eq->saturation = av_clipf(av_expr_eval(eq->saturation_pexpr, eq->var_values, eq), 0.0, 3.0);
for (i = 1; i < 3; i++) {
eq->param[i].contrast = eq->saturation;
eq->param[i].lut_clean = 0;
check_values(&eq->param[i], eq);
}
}
static int set_expr(AVExpr **pexpr, const char *expr, const char *option, void *log_ctx)
{
int ret;
AVExpr *old = NULL;
if (*pexpr)
old = *pexpr;
ret = av_expr_parse(pexpr, expr, var_names, NULL, NULL, NULL, NULL, 0, log_ctx);
if (ret < 0) {
av_log(log_ctx, AV_LOG_ERROR,
"Error when parsing the expression '%s' for %s\n",
expr, option);
*pexpr = old;
return ret;
}
av_expr_free(old);
return 0;
}
static int initialize(AVFilterContext *ctx)
{
EQContext *eq = ctx->priv;
int ret;
eq->process = process_c;
if ((ret = set_expr(&eq->contrast_pexpr, eq->contrast_expr, "contrast", ctx)) < 0 ||
(ret = set_expr(&eq->brightness_pexpr, eq->brightness_expr, "brightness", ctx)) < 0 ||
(ret = set_expr(&eq->saturation_pexpr, eq->saturation_expr, "saturation", ctx)) < 0 ||
(ret = set_expr(&eq->gamma_pexpr, eq->gamma_expr, "gamma", ctx)) < 0 ||
(ret = set_expr(&eq->gamma_r_pexpr, eq->gamma_r_expr, "gamma_r", ctx)) < 0 ||
(ret = set_expr(&eq->gamma_g_pexpr, eq->gamma_g_expr, "gamma_g", ctx)) < 0 ||
(ret = set_expr(&eq->gamma_b_pexpr, eq->gamma_b_expr, "gamma_b", ctx)) < 0 ||
(ret = set_expr(&eq->gamma_weight_pexpr, eq->gamma_weight_expr, "gamma_weight", ctx)) < 0 )
return ret;
if (ARCH_X86)
ff_eq_init_x86(eq);
if (eq->eval_mode == EVAL_MODE_INIT) {
set_gamma(eq);
set_contrast(eq);
set_brightness(eq);
set_saturation(eq);
}
return 0;
}
static void uninit(AVFilterContext *ctx)
{
EQContext *eq = ctx->priv;
av_expr_free(eq->contrast_pexpr); eq->contrast_pexpr = NULL;
av_expr_free(eq->brightness_pexpr); eq->brightness_pexpr = NULL;
av_expr_free(eq->saturation_pexpr); eq->saturation_pexpr = NULL;
av_expr_free(eq->gamma_pexpr); eq->gamma_pexpr = NULL;
av_expr_free(eq->gamma_weight_pexpr); eq->gamma_weight_pexpr = NULL;
av_expr_free(eq->gamma_r_pexpr); eq->gamma_r_pexpr = NULL;
av_expr_free(eq->gamma_g_pexpr); eq->gamma_g_pexpr = NULL;
av_expr_free(eq->gamma_b_pexpr); eq->gamma_b_pexpr = NULL;
}
static int config_props(AVFilterLink *inlink)
{
EQContext *eq = inlink->dst->priv;
eq->var_values[VAR_N] = 0;
eq->var_values[VAR_R] = inlink->frame_rate.num == 0 || inlink->frame_rate.den == 0 ?
NAN : av_q2d(inlink->frame_rate);
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
static const enum AVPixelFormat pixel_fmts_eq[] = {
AV_PIX_FMT_GRAY8,
AV_PIX_FMT_YUV410P,
AV_PIX_FMT_YUV411P,
AV_PIX_FMT_YUV420P,
AV_PIX_FMT_YUV422P,
AV_PIX_FMT_YUV444P,
AV_PIX_FMT_NONE
};
AVFilterFormats *fmts_list = ff_make_format_list(pixel_fmts_eq);
if (!fmts_list)
return AVERROR(ENOMEM);
return ff_set_common_formats(ctx, fmts_list);
}
#define TS2T(ts, tb) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts) * av_q2d(tb))
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = inlink->dst->outputs[0];
EQContext *eq = ctx->priv;
AVFrame *out;
int64_t pos = in->pkt_pos;
const AVPixFmtDescriptor *desc;
int i;
out = ff_get_video_buffer(outlink, inlink->w, inlink->h);
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
desc = av_pix_fmt_desc_get(inlink->format);
eq->var_values[VAR_N] = inlink->frame_count_out;
eq->var_values[VAR_POS] = pos == -1 ? NAN : pos;
eq->var_values[VAR_T] = TS2T(in->pts, inlink->time_base);
if (eq->eval_mode == EVAL_MODE_FRAME) {
set_gamma(eq);
set_contrast(eq);
set_brightness(eq);
set_saturation(eq);
}
for (i = 0; i < desc->nb_components; i++) {
int w = inlink->w;
int h = inlink->h;
if (i == 1 || i == 2) {
w = AV_CEIL_RSHIFT(w, desc->log2_chroma_w);
h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
}
if (eq->param[i].adjust)
eq->param[i].adjust(&eq->param[i], out->data[i], out->linesize[i],
in->data[i], in->linesize[i], w, h);
else
av_image_copy_plane(out->data[i], out->linesize[i],
in->data[i], in->linesize[i], w, h);
}
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static inline int set_param(AVExpr **pexpr, const char *args, const char *cmd,
void (*set_fn)(EQContext *eq), AVFilterContext *ctx)
{
EQContext *eq = ctx->priv;
int ret;
if ((ret = set_expr(pexpr, args, cmd, ctx)) < 0)
return ret;
if (eq->eval_mode == EVAL_MODE_INIT)
set_fn(eq);
return 0;
}
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
char *res, int res_len, int flags)
{
EQContext *eq = ctx->priv;
#define SET_PARAM(param_name, set_fn_name) \
if (!strcmp(cmd, #param_name)) return set_param(&eq->param_name##_pexpr, args, cmd, set_##set_fn_name, ctx);
SET_PARAM(contrast, contrast)
else SET_PARAM(brightness, brightness)
else SET_PARAM(saturation, saturation)
else SET_PARAM(gamma, gamma)
else SET_PARAM(gamma_r, gamma)
else SET_PARAM(gamma_g, gamma)
else SET_PARAM(gamma_b, gamma)
else SET_PARAM(gamma_weight, gamma)
else return AVERROR(ENOSYS);
}
static const AVFilterPad eq_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_props,
},
{ NULL }
};
static const AVFilterPad eq_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
#define OFFSET(x) offsetof(EQContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption eq_options[] = {
{ "contrast", "set the contrast adjustment, negative values give a negative image",
OFFSET(contrast_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "brightness", "set the brightness adjustment",
OFFSET(brightness_expr), AV_OPT_TYPE_STRING, {.str = "0.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "saturation", "set the saturation adjustment",
OFFSET(saturation_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "gamma", "set the initial gamma value",
OFFSET(gamma_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "gamma_r", "gamma value for red",
OFFSET(gamma_r_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "gamma_g", "gamma value for green",
OFFSET(gamma_g_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "gamma_b", "gamma value for blue",
OFFSET(gamma_b_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "gamma_weight", "set the gamma weight which reduces the effect of gamma on bright areas",
OFFSET(gamma_weight_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
{ "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
{ "frame", "eval expressions per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
{ NULL }
};
AVFILTER_DEFINE_CLASS(eq);
AVFilter ff_vf_eq = {
.name = "eq",
.description = NULL_IF_CONFIG_SMALL("Adjust brightness, contrast, gamma, and saturation."),
.priv_size = sizeof(EQContext),
.priv_class = &eq_class,
.inputs = eq_inputs,
.outputs = eq_outputs,
.process_command = process_command,
.query_formats = query_formats,
.init = initialize,
.uninit = uninit,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};