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/*
* Copyright (c) 2015 Timo Rothenpieler <timo@rothenpieler.org>
*
* 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/imgutils.h"
#include "libavutil/intreadwrite.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
typedef struct ChromakeyContext {
const AVClass *class;
uint8_t chromakey_rgba[4];
uint16_t chromakey_uv[2];
float similarity;
float blend;
int is_yuv;
int depth;
int mid;
int max;
int hsub_log2;
int vsub_log2;
int (*do_slice)(AVFilterContext *ctx, void *arg,
int jobnr, int nb_jobs);
} ChromakeyContext;
static uint8_t do_chromakey_pixel(ChromakeyContext *ctx, uint8_t u[9], uint8_t v[9])
{
double diff = 0.0;
int du, dv, i;
for (i = 0; i < 9; ++i) {
du = (int)u[i] - ctx->chromakey_uv[0];
dv = (int)v[i] - ctx->chromakey_uv[1];
diff += sqrt((du * du + dv * dv) / (255.0 * 255.0 * 2));
}
diff /= 9.0;
if (ctx->blend > 0.0001) {
return av_clipd((diff - ctx->similarity) / ctx->blend, 0.0, 1.0) * 255.0;
} else {
return (diff > ctx->similarity) ? 255 : 0;
}
}
static uint16_t do_chromakey_pixel16(ChromakeyContext *ctx, uint16_t u[9], uint16_t v[9])
{
double max = ctx->max;
double diff = 0.0;
int du, dv, i;
for (i = 0; i < 9; ++i) {
du = (int)u[i] - ctx->chromakey_uv[0];
dv = (int)v[i] - ctx->chromakey_uv[1];
diff += sqrt((du * du + dv * dv) / (max * max * 2));
}
diff /= 9.0;
if (ctx->blend > 0.0001) {
return av_clipd((diff - ctx->similarity) / ctx->blend, 0.0, 1.0) * max;
} else {
return (diff > ctx->similarity) ? max : 0;
}
}
static av_always_inline void get_pixel_uv(AVFrame *frame, int hsub_log2, int vsub_log2, int x, int y, uint8_t *u, uint8_t *v)
{
if (x < 0 || x >= frame->width || y < 0 || y >= frame->height)
return;
x >>= hsub_log2;
y >>= vsub_log2;
*u = frame->data[1][frame->linesize[1] * y + x];
*v = frame->data[2][frame->linesize[2] * y + x];
}
static av_always_inline void get_pixel16_uv(AVFrame *frame, int hsub_log2, int vsub_log2, int x, int y, uint16_t *u, uint16_t *v)
{
if (x < 0 || x >= frame->width || y < 0 || y >= frame->height)
return;
x >>= hsub_log2;
y >>= vsub_log2;
*u = AV_RN16(&frame->data[1][frame->linesize[1] * y + 2 * x]);
*v = AV_RN16(&frame->data[2][frame->linesize[2] * y + 2 * x]);
}
static int do_chromakey_slice(AVFilterContext *avctx, void *arg, int jobnr, int nb_jobs)
{
AVFrame *frame = arg;
const int slice_start = (frame->height * jobnr) / nb_jobs;
const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
ChromakeyContext *ctx = avctx->priv;
int x, y, xo, yo;
uint8_t u[9], v[9];
memset(u, ctx->chromakey_uv[0], sizeof(u));
memset(v, ctx->chromakey_uv[1], sizeof(v));
for (y = slice_start; y < slice_end; ++y) {
for (x = 0; x < frame->width; ++x) {
for (yo = 0; yo < 3; ++yo) {
for (xo = 0; xo < 3; ++xo) {
get_pixel_uv(frame, ctx->hsub_log2, ctx->vsub_log2, x + xo - 1, y + yo - 1, &u[yo * 3 + xo], &v[yo * 3 + xo]);
}
}
frame->data[3][frame->linesize[3] * y + x] = do_chromakey_pixel(ctx, u, v);
}
}
return 0;
}
static int do_chromakey16_slice(AVFilterContext *avctx, void *arg, int jobnr, int nb_jobs)
{
AVFrame *frame = arg;
const int slice_start = (frame->height * jobnr) / nb_jobs;
const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
ChromakeyContext *ctx = avctx->priv;
int x, y, xo, yo;
uint16_t u[9], v[9];
for (int i = 0; i < 9; i++) {
u[i] = ctx->chromakey_uv[0];
v[i] = ctx->chromakey_uv[1];
}
for (y = slice_start; y < slice_end; ++y) {
for (x = 0; x < frame->width; ++x) {
uint16_t *dst = (uint16_t *)(frame->data[3] + frame->linesize[3] * y);
for (yo = 0; yo < 3; ++yo) {
for (xo = 0; xo < 3; ++xo) {
get_pixel16_uv(frame, ctx->hsub_log2, ctx->vsub_log2, x + xo - 1, y + yo - 1, &u[yo * 3 + xo], &v[yo * 3 + xo]);
}
}
dst[x] = do_chromakey_pixel16(ctx, u, v);
}
}
return 0;
}
static int do_chromahold_slice(AVFilterContext *avctx, void *arg, int jobnr, int nb_jobs)
{
ChromakeyContext *ctx = avctx->priv;
AVFrame *frame = arg;
const int slice_start = ((frame->height >> ctx->vsub_log2) * jobnr) / nb_jobs;
const int slice_end = ((frame->height >> ctx->vsub_log2) * (jobnr + 1)) / nb_jobs;
int x, y, alpha;
for (y = slice_start; y < slice_end; ++y) {
for (x = 0; x < frame->width >> ctx->hsub_log2; ++x) {
int u = frame->data[1][frame->linesize[1] * y + x];
int v = frame->data[2][frame->linesize[2] * y + x];
double diff;
int du, dv;
du = u - ctx->chromakey_uv[0];
dv = v - ctx->chromakey_uv[1];
diff = sqrt((du * du + dv * dv) / (255.0 * 255.0));
alpha = diff > ctx->similarity;
if (ctx->blend > 0.0001) {
double f = 1. - av_clipd((diff - ctx->similarity) / ctx->blend, 0.0, 1.0);
frame->data[1][frame->linesize[1] * y + x] = 128 + (u - 128) * f;
frame->data[2][frame->linesize[2] * y + x] = 128 + (v - 128) * f;
} else if (alpha) {
frame->data[1][frame->linesize[1] * y + x] = 128;
frame->data[2][frame->linesize[2] * y + x] = 128;
}
}
}
return 0;
}
static int do_chromahold16_slice(AVFilterContext *avctx, void *arg, int jobnr, int nb_jobs)
{
ChromakeyContext *ctx = avctx->priv;
AVFrame *frame = arg;
const int slice_start = ((frame->height >> ctx->vsub_log2) * jobnr) / nb_jobs;
const int slice_end = ((frame->height >> ctx->vsub_log2) * (jobnr + 1)) / nb_jobs;
const int mid = ctx->mid;
double max = ctx->max;
int x, y, alpha;
for (y = slice_start; y < slice_end; ++y) {
for (x = 0; x < frame->width >> ctx->hsub_log2; ++x) {
int u = AV_RN16(&frame->data[1][frame->linesize[1] * y + 2 * x]);
int v = AV_RN16(&frame->data[2][frame->linesize[2] * y + 2 * x]);
double diff;
int du, dv;
du = u - ctx->chromakey_uv[0];
dv = v - ctx->chromakey_uv[1];
diff = sqrt((du * du + dv * dv) / (max * max));
alpha = diff > ctx->similarity;
if (ctx->blend > 0.0001) {
double f = 1. - av_clipd((diff - ctx->similarity) / ctx->blend, 0.0, 1.0);
AV_WN16(&frame->data[1][frame->linesize[1] * y + 2 * x], mid + (u - mid) * f);
AV_WN16(&frame->data[2][frame->linesize[2] * y + 2 * x], mid + (v - mid) * f);
} else if (alpha) {
AV_WN16(&frame->data[1][frame->linesize[1] * y + 2 * x], mid);
AV_WN16(&frame->data[2][frame->linesize[2] * y + 2 * x], mid);
}
}
}
return 0;
}
static int filter_frame(AVFilterLink *link, AVFrame *frame)
{
AVFilterContext *avctx = link->dst;
ChromakeyContext *ctx = avctx->priv;
int res;
if (res = ff_filter_execute(avctx, ctx->do_slice, frame, NULL,
FFMIN(frame->height, ff_filter_get_nb_threads(avctx))))
return res;
return ff_filter_frame(avctx->outputs[0], frame);
}
#define FIXNUM(x) lrint((x) * (1 << 10))
#define RGB_TO_U(rgb) (((- FIXNUM(0.16874) * rgb[0] - FIXNUM(0.33126) * rgb[1] + FIXNUM(0.50000) * rgb[2] + (1 << 9) - 1) >> 10) + 128)
#define RGB_TO_V(rgb) ((( FIXNUM(0.50000) * rgb[0] - FIXNUM(0.41869) * rgb[1] - FIXNUM(0.08131) * rgb[2] + (1 << 9) - 1) >> 10) + 128)
static av_cold int config_output(AVFilterLink *outlink)
{
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format);
AVFilterContext *avctx = outlink->src;
ChromakeyContext *ctx = avctx->priv;
int factor;
ctx->depth = desc->comp[0].depth;
ctx->mid = 1 << (ctx->depth - 1);
ctx->max = (1 << ctx->depth) - 1;
factor = 1 << (ctx->depth - 8);
if (ctx->is_yuv) {
ctx->chromakey_uv[0] = ctx->chromakey_rgba[1] * factor;
ctx->chromakey_uv[1] = ctx->chromakey_rgba[2] * factor;
} else {
ctx->chromakey_uv[0] = RGB_TO_U(ctx->chromakey_rgba) * factor;
ctx->chromakey_uv[1] = RGB_TO_V(ctx->chromakey_rgba) * factor;
}
if (!strcmp(avctx->filter->name, "chromakey")) {
ctx->do_slice = ctx->depth <= 8 ? do_chromakey_slice : do_chromakey16_slice;
} else {
ctx->do_slice = ctx->depth <= 8 ? do_chromahold_slice: do_chromahold16_slice;
}
return 0;
}
static av_cold int query_formats(AVFilterContext *avctx)
{
static const enum AVPixelFormat pixel_fmts[] = {
AV_PIX_FMT_YUVA420P,
AV_PIX_FMT_YUVA422P,
AV_PIX_FMT_YUVA444P,
AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA444P9,
AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA444P10,
AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA444P12,
AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
AV_PIX_FMT_NONE
};
static const enum AVPixelFormat hold_pixel_fmts[] = {
AV_PIX_FMT_YUV420P,
AV_PIX_FMT_YUV422P,
AV_PIX_FMT_YUV444P,
AV_PIX_FMT_YUVA420P,
AV_PIX_FMT_YUVA422P,
AV_PIX_FMT_YUVA444P,
AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV420P12,
AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV420P14,
AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA444P9,
AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA444P10,
AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA444P12,
AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
AV_PIX_FMT_NONE
};
const enum AVPixelFormat *pix_fmts;
pix_fmts = !strcmp(avctx->filter->name, "chromahold") ? hold_pixel_fmts : pixel_fmts;
return ff_set_common_formats_from_list(avctx, pix_fmts);
}
static av_cold int config_input(AVFilterLink *inlink)
{
AVFilterContext *avctx = inlink->dst;
ChromakeyContext *ctx = avctx->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
ctx->hsub_log2 = desc->log2_chroma_w;
ctx->vsub_log2 = desc->log2_chroma_h;
return 0;
}
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
char *res, int res_len, int flags)
{
int ret;
ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
if (ret < 0)
return ret;
return config_output(ctx->outputs[0]);
}
static const AVFilterPad chromakey_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.flags = AVFILTERPAD_FLAG_NEEDS_WRITABLE,
.filter_frame = filter_frame,
.config_props = config_input,
},
{ NULL }
};
static const AVFilterPad chromakey_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
{ NULL }
};
#define OFFSET(x) offsetof(ChromakeyContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
static const AVOption chromakey_options[] = {
{ "color", "set the chromakey key color", OFFSET(chromakey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, 0, 0, FLAGS },
{ "similarity", "set the chromakey similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.01, 1.0, FLAGS },
{ "blend", "set the chromakey key blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
{ "yuv", "color parameter is in yuv instead of rgb", OFFSET(is_yuv), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(chromakey);
const AVFilter ff_vf_chromakey = {
.name = "chromakey",
.description = NULL_IF_CONFIG_SMALL("Turns a certain color into transparency. Operates on YUV colors."),
.priv_size = sizeof(ChromakeyContext),
.priv_class = &chromakey_class,
.query_formats = query_formats,
.inputs = chromakey_inputs,
.outputs = chromakey_outputs,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
.process_command = process_command,
};
static const AVOption chromahold_options[] = {
{ "color", "set the chromahold key color", OFFSET(chromakey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, 0, 0, FLAGS },
{ "similarity", "set the chromahold similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.01, 1.0, FLAGS },
{ "blend", "set the chromahold blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
{ "yuv", "color parameter is in yuv instead of rgb", OFFSET(is_yuv), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
{ NULL }
};
static const AVFilterPad chromahold_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.flags = AVFILTERPAD_FLAG_NEEDS_WRITABLE,
.filter_frame = filter_frame,
.config_props = config_input,
},
{ NULL }
};
static const AVFilterPad chromahold_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
{ NULL }
};
AVFILTER_DEFINE_CLASS(chromahold);
const AVFilter ff_vf_chromahold = {
.name = "chromahold",
.description = NULL_IF_CONFIG_SMALL("Turns a certain color range into gray."),
.priv_size = sizeof(ChromakeyContext),
.priv_class = &chromahold_class,
.query_formats = query_formats,
.inputs = chromahold_inputs,
.outputs = chromahold_outputs,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
.process_command = process_command,
};
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