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/*
* Copyright (c) 2011 Stefano Sabatini
*
* 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
* Compute a look-up table for binding the input value to the output
* value, and apply it to input video.
*/
#include "libavutil/attributes.h"
#include "libavutil/bswap.h"
#include "libavutil/common.h"
#include "libavutil/eval.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "drawutils.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
static const char *const var_names[] = {
"w", ///< width of the input video
"h", ///< height of the input video
"val", ///< input value for the pixel
"maxval", ///< max value for the pixel
"minval", ///< min value for the pixel
"negval", ///< negated value
"clipval",
NULL
};
enum var_name {
VAR_W,
VAR_H,
VAR_VAL,
VAR_MAXVAL,
VAR_MINVAL,
VAR_NEGVAL,
VAR_CLIPVAL,
VAR_VARS_NB
};
typedef struct LutContext {
const AVClass *class;
uint16_t lut[4][256 * 256]; ///< lookup table for each component
char *comp_expr_str[4];
AVExpr *comp_expr[4];
int hsub, vsub;
double var_values[VAR_VARS_NB];
int is_rgb, is_yuv;
int is_planar;
int is_16bit;
int step;
int negate_alpha; /* only used by negate */
} LutContext;
#define Y 0
#define U 1
#define V 2
#define R 0
#define G 1
#define B 2
#define A 3
#define OFFSET(x) offsetof(LutContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption options[] = {
{ "c0", "set component #0 expression", OFFSET(comp_expr_str[0]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "c1", "set component #1 expression", OFFSET(comp_expr_str[1]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "c2", "set component #2 expression", OFFSET(comp_expr_str[2]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "c3", "set component #3 expression", OFFSET(comp_expr_str[3]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "y", "set Y expression", OFFSET(comp_expr_str[Y]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "u", "set U expression", OFFSET(comp_expr_str[U]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "v", "set V expression", OFFSET(comp_expr_str[V]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "r", "set R expression", OFFSET(comp_expr_str[R]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "g", "set G expression", OFFSET(comp_expr_str[G]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "b", "set B expression", OFFSET(comp_expr_str[B]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ "a", "set A expression", OFFSET(comp_expr_str[A]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
{ NULL }
};
static av_cold void uninit(AVFilterContext *ctx)
{
LutContext *s = ctx->priv;
int i;
for (i = 0; i < 4; i++) {
av_expr_free(s->comp_expr[i]);
s->comp_expr[i] = NULL;
av_freep(&s->comp_expr_str[i]);
}
}
#define YUV_FORMATS \
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_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P, \
AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P, \
AV_PIX_FMT_YUVJ440P, \
AV_PIX_FMT_YUV444P9LE, AV_PIX_FMT_YUV422P9LE, AV_PIX_FMT_YUV420P9LE, \
AV_PIX_FMT_YUV444P10LE, AV_PIX_FMT_YUV422P10LE, AV_PIX_FMT_YUV420P10LE, AV_PIX_FMT_YUV440P10LE, \
AV_PIX_FMT_YUV444P12LE, AV_PIX_FMT_YUV422P12LE, AV_PIX_FMT_YUV420P12LE, AV_PIX_FMT_YUV440P12LE, \
AV_PIX_FMT_YUV444P14LE, AV_PIX_FMT_YUV422P14LE, AV_PIX_FMT_YUV420P14LE, \
AV_PIX_FMT_YUV444P16LE, AV_PIX_FMT_YUV422P16LE, AV_PIX_FMT_YUV420P16LE, \
AV_PIX_FMT_YUVA444P16LE, AV_PIX_FMT_YUVA422P16LE, AV_PIX_FMT_YUVA420P16LE
#define RGB_FORMATS \
AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA, \
AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA, \
AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24, \
AV_PIX_FMT_RGB48LE, AV_PIX_FMT_RGBA64LE, \
AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, \
AV_PIX_FMT_GBRP9LE, AV_PIX_FMT_GBRP10LE, \
AV_PIX_FMT_GBRP12LE, AV_PIX_FMT_GBRP14LE, \
AV_PIX_FMT_GBRP16LE, AV_PIX_FMT_GBRAP12LE, \
AV_PIX_FMT_GBRAP16LE
static const enum AVPixelFormat yuv_pix_fmts[] = { YUV_FORMATS, AV_PIX_FMT_NONE };
static const enum AVPixelFormat rgb_pix_fmts[] = { RGB_FORMATS, AV_PIX_FMT_NONE };
static const enum AVPixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, AV_PIX_FMT_NONE };
static int query_formats(AVFilterContext *ctx)
{
LutContext *s = ctx->priv;
const enum AVPixelFormat *pix_fmts = s->is_rgb ? rgb_pix_fmts :
s->is_yuv ? yuv_pix_fmts :
all_pix_fmts;
AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
if (!fmts_list)
return AVERROR(ENOMEM);
return ff_set_common_formats(ctx, fmts_list);
}
/**
* Clip value val in the minval - maxval range.
*/
static double clip(void *opaque, double val)
{
LutContext *s = opaque;
double minval = s->var_values[VAR_MINVAL];
double maxval = s->var_values[VAR_MAXVAL];
return av_clip(val, minval, maxval);
}
/**
* Compute gamma correction for value val, assuming the minval-maxval
* range, val is clipped to a value contained in the same interval.
*/
static double compute_gammaval(void *opaque, double gamma)
{
LutContext *s = opaque;
double val = s->var_values[VAR_CLIPVAL];
double minval = s->var_values[VAR_MINVAL];
double maxval = s->var_values[VAR_MAXVAL];
return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
}
/**
* Compute ITU Rec.709 gamma correction of value val.
*/
static double compute_gammaval709(void *opaque, double gamma)
{
LutContext *s = opaque;
double val = s->var_values[VAR_CLIPVAL];
double minval = s->var_values[VAR_MINVAL];
double maxval = s->var_values[VAR_MAXVAL];
double level = (val - minval) / (maxval - minval);
level = level < 0.018 ? 4.5 * level
: 1.099 * pow(level, 1.0 / gamma) - 0.099;
return level * (maxval - minval) + minval;
}
static double (* const funcs1[])(void *, double) = {
clip,
compute_gammaval,
compute_gammaval709,
NULL
};
static const char * const funcs1_names[] = {
"clip",
"gammaval",
"gammaval709",
NULL
};
static int config_props(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
LutContext *s = ctx->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
uint8_t rgba_map[4]; /* component index -> RGBA color index map */
int min[4], max[4];
int val, color, ret;
s->hsub = desc->log2_chroma_w;
s->vsub = desc->log2_chroma_h;
s->var_values[VAR_W] = inlink->w;
s->var_values[VAR_H] = inlink->h;
s->is_16bit = desc->comp[0].depth > 8;
switch (inlink->format) {
case AV_PIX_FMT_YUV410P:
case AV_PIX_FMT_YUV411P:
case AV_PIX_FMT_YUV420P:
case AV_PIX_FMT_YUV422P:
case AV_PIX_FMT_YUV440P:
case AV_PIX_FMT_YUV444P:
case AV_PIX_FMT_YUVA420P:
case AV_PIX_FMT_YUVA422P:
case AV_PIX_FMT_YUVA444P:
case AV_PIX_FMT_YUV420P9LE:
case AV_PIX_FMT_YUV422P9LE:
case AV_PIX_FMT_YUV444P9LE:
case AV_PIX_FMT_YUVA420P9LE:
case AV_PIX_FMT_YUVA422P9LE:
case AV_PIX_FMT_YUVA444P9LE:
case AV_PIX_FMT_YUV420P10LE:
case AV_PIX_FMT_YUV422P10LE:
case AV_PIX_FMT_YUV440P10LE:
case AV_PIX_FMT_YUV444P10LE:
case AV_PIX_FMT_YUVA420P10LE:
case AV_PIX_FMT_YUVA422P10LE:
case AV_PIX_FMT_YUVA444P10LE:
case AV_PIX_FMT_YUV420P12LE:
case AV_PIX_FMT_YUV422P12LE:
case AV_PIX_FMT_YUV440P12LE:
case AV_PIX_FMT_YUV444P12LE:
case AV_PIX_FMT_YUV420P14LE:
case AV_PIX_FMT_YUV422P14LE:
case AV_PIX_FMT_YUV444P14LE:
case AV_PIX_FMT_YUV420P16LE:
case AV_PIX_FMT_YUV422P16LE:
case AV_PIX_FMT_YUV444P16LE:
case AV_PIX_FMT_YUVA420P16LE:
case AV_PIX_FMT_YUVA422P16LE:
case AV_PIX_FMT_YUVA444P16LE:
min[Y] = 16 * (1 << (desc->comp[0].depth - 8));
min[U] = 16 * (1 << (desc->comp[1].depth - 8));
min[V] = 16 * (1 << (desc->comp[2].depth - 8));
min[A] = 0;
max[Y] = 235 * (1 << (desc->comp[0].depth - 8));
max[U] = 240 * (1 << (desc->comp[1].depth - 8));
max[V] = 240 * (1 << (desc->comp[2].depth - 8));
max[A] = (1 << desc->comp[0].depth) - 1;
break;
case AV_PIX_FMT_RGB48LE:
case AV_PIX_FMT_RGBA64LE:
min[0] = min[1] = min[2] = min[3] = 0;
max[0] = max[1] = max[2] = max[3] = 65535;
break;
default:
min[0] = min[1] = min[2] = min[3] = 0;
max[0] = max[1] = max[2] = max[3] = 255 * (1 << (desc->comp[0].depth - 8));
}
s->is_yuv = s->is_rgb = 0;
s->is_planar = desc->flags & AV_PIX_FMT_FLAG_PLANAR;
if (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) s->is_yuv = 1;
else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) s->is_rgb = 1;
if (s->is_rgb) {
ff_fill_rgba_map(rgba_map, inlink->format);
s->step = av_get_bits_per_pixel(desc) >> 3;
if (s->is_16bit) {
s->step = s->step >> 1;
}
}
for (color = 0; color < desc->nb_components; color++) {
double res;
int comp = s->is_rgb ? rgba_map[color] : color;
/* create the parsed expression */
av_expr_free(s->comp_expr[color]);
s->comp_expr[color] = NULL;
ret = av_expr_parse(&s->comp_expr[color], s->comp_expr_str[color],
var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
if (ret < 0) {
av_log(ctx, AV_LOG_ERROR,
"Error when parsing the expression '%s' for the component %d and color %d.\n",
s->comp_expr_str[comp], comp, color);
return AVERROR(EINVAL);
}
/* compute the lut */
s->var_values[VAR_MAXVAL] = max[color];
s->var_values[VAR_MINVAL] = min[color];
for (val = 0; val < (1 << desc->comp[0].depth); val++) {
s->var_values[VAR_VAL] = val;
s->var_values[VAR_CLIPVAL] = av_clip(val, min[color], max[color]);
s->var_values[VAR_NEGVAL] =
av_clip(min[color] + max[color] - s->var_values[VAR_VAL],
min[color], max[color]);
res = av_expr_eval(s->comp_expr[color], s->var_values, s);
if (isnan(res)) {
av_log(ctx, AV_LOG_ERROR,
"Error when evaluating the expression '%s' for the value %d for the component %d.\n",
s->comp_expr_str[color], val, comp);
return AVERROR(EINVAL);
}
s->lut[comp][val] = av_clip((int)res, 0, max[A]);
av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, s->lut[comp][val]);
}
}
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVFilterContext *ctx = inlink->dst;
LutContext *s = ctx->priv;
AVFilterLink *outlink = ctx->outputs[0];
AVFrame *out;
int i, j, plane, direct = 0;
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);
}
if (s->is_rgb && s->is_16bit && !s->is_planar) {
/* packed, 16-bit */
uint16_t *inrow, *outrow, *inrow0, *outrow0;
const int w = inlink->w;
const int h = in->height;
const uint16_t (*tab)[256*256] = (const uint16_t (*)[256*256])s->lut;
const int in_linesize = in->linesize[0] / 2;
const int out_linesize = out->linesize[0] / 2;
const int step = s->step;
inrow0 = (uint16_t*) in ->data[0];
outrow0 = (uint16_t*) out->data[0];
for (i = 0; i < h; i ++) {
inrow = inrow0;
outrow = outrow0;
for (j = 0; j < w; j++) {
switch (step) {
#if HAVE_BIGENDIAN
case 4: outrow[3] = av_bswap16(tab[3][av_bswap16(inrow[3])]); // Fall-through
case 3: outrow[2] = av_bswap16(tab[2][av_bswap16(inrow[2])]); // Fall-through
case 2: outrow[1] = av_bswap16(tab[1][av_bswap16(inrow[1])]); // Fall-through
default: outrow[0] = av_bswap16(tab[0][av_bswap16(inrow[0])]);
#else
case 4: outrow[3] = tab[3][inrow[3]]; // Fall-through
case 3: outrow[2] = tab[2][inrow[2]]; // Fall-through
case 2: outrow[1] = tab[1][inrow[1]]; // Fall-through
default: outrow[0] = tab[0][inrow[0]];
#endif
}
outrow += step;
inrow += step;
}
inrow0 += in_linesize;
outrow0 += out_linesize;
}
} else if (s->is_rgb && !s->is_planar) {
/* packed */
uint8_t *inrow, *outrow, *inrow0, *outrow0;
const int w = inlink->w;
const int h = in->height;
const uint16_t (*tab)[256*256] = (const uint16_t (*)[256*256])s->lut;
const int in_linesize = in->linesize[0];
const int out_linesize = out->linesize[0];
const int step = s->step;
inrow0 = in ->data[0];
outrow0 = out->data[0];
for (i = 0; i < h; i ++) {
inrow = inrow0;
outrow = outrow0;
for (j = 0; j < w; j++) {
switch (step) {
case 4: outrow[3] = tab[3][inrow[3]]; // Fall-through
case 3: outrow[2] = tab[2][inrow[2]]; // Fall-through
case 2: outrow[1] = tab[1][inrow[1]]; // Fall-through
default: outrow[0] = tab[0][inrow[0]];
}
outrow += step;
inrow += step;
}
inrow0 += in_linesize;
outrow0 += out_linesize;
}
} else if (s->is_16bit) {
// planar >8 bit depth
uint16_t *inrow, *outrow;
for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
int h = AV_CEIL_RSHIFT(inlink->h, vsub);
int w = AV_CEIL_RSHIFT(inlink->w, hsub);
const uint16_t *tab = s->lut[plane];
const int in_linesize = in->linesize[plane] / 2;
const int out_linesize = out->linesize[plane] / 2;
inrow = (uint16_t *)in ->data[plane];
outrow = (uint16_t *)out->data[plane];
for (i = 0; i < h; i++) {
for (j = 0; j < w; j++) {
#if HAVE_BIGENDIAN
outrow[j] = av_bswap16(tab[av_bswap16(inrow[j])]);
#else
outrow[j] = tab[inrow[j]];
#endif
}
inrow += in_linesize;
outrow += out_linesize;
}
}
} else {
/* planar 8bit depth */
uint8_t *inrow, *outrow;
for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
int h = AV_CEIL_RSHIFT(inlink->h, vsub);
int w = AV_CEIL_RSHIFT(inlink->w, hsub);
const uint16_t *tab = s->lut[plane];
const int in_linesize = in->linesize[plane];
const int out_linesize = out->linesize[plane];
inrow = in ->data[plane];
outrow = out->data[plane];
for (i = 0; i < h; i++) {
for (j = 0; j < w; j++)
outrow[j] = tab[inrow[j]];
inrow += in_linesize;
outrow += out_linesize;
}
}
}
if (!direct)
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static const AVFilterPad inputs[] = {
{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_props,
},
{ NULL }
};
static const AVFilterPad outputs[] = {
{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
#define DEFINE_LUT_FILTER(name_, description_) \
AVFilter ff_vf_##name_ = { \
.name = #name_, \
.description = NULL_IF_CONFIG_SMALL(description_), \
.priv_size = sizeof(LutContext), \
.priv_class = &name_ ## _class, \
.init = name_##_init, \
.uninit = uninit, \
.query_formats = query_formats, \
.inputs = inputs, \
.outputs = outputs, \
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, \
}
#if CONFIG_LUT_FILTER
#define lut_options options
AVFILTER_DEFINE_CLASS(lut);
static int lut_init(AVFilterContext *ctx)
{
return 0;
}
DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.");
#endif
#if CONFIG_LUTYUV_FILTER
#define lutyuv_options options
AVFILTER_DEFINE_CLASS(lutyuv);
static av_cold int lutyuv_init(AVFilterContext *ctx)
{
LutContext *s = ctx->priv;
s->is_yuv = 1;
return 0;
}
DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.");
#endif
#if CONFIG_LUTRGB_FILTER
#define lutrgb_options options
AVFILTER_DEFINE_CLASS(lutrgb);
static av_cold int lutrgb_init(AVFilterContext *ctx)
{
LutContext *s = ctx->priv;
s->is_rgb = 1;
return 0;
}
DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.");
#endif
#if CONFIG_NEGATE_FILTER
static const AVOption negate_options[] = {
{ "negate_alpha", NULL, OFFSET(negate_alpha), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(negate);
static av_cold int negate_init(AVFilterContext *ctx)
{
LutContext *s = ctx->priv;
int i;
av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", s->negate_alpha);
for (i = 0; i < 4; i++) {
s->comp_expr_str[i] = av_strdup((i == 3 && !s->negate_alpha) ?
"val" : "negval");
if (!s->comp_expr_str[i]) {
uninit(ctx);
return AVERROR(ENOMEM);
}
}
return 0;
}
DEFINE_LUT_FILTER(negate, "Negate input video.");
#endif
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