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|
/*
* Copyright (c) 2010 Stefano Sabatini
* Copyright (c) 2010 Baptiste Coudurier
* Copyright (c) 2007 Bobby Bingham
*
* 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
* overlay one video on top of another
*/
#include "avfilter.h"
#include "formats.h"
#include "libavutil/common.h"
#include "libavutil/eval.h"
#include "libavutil/avstring.h"
#include "libavutil/pixdesc.h"
#include "libavutil/imgutils.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/timestamp.h"
#include "internal.h"
#include "drawutils.h"
#include "framesync2.h"
#include "video.h"
static const char *const var_names[] = {
"main_w", "W", ///< width of the main video
"main_h", "H", ///< height of the main video
"overlay_w", "w", ///< width of the overlay video
"overlay_h", "h", ///< height of the overlay video
"hsub",
"vsub",
"x",
"y",
"n", ///< number of frame
"pos", ///< position in the file
"t", ///< timestamp expressed in seconds
NULL
};
enum var_name {
VAR_MAIN_W, VAR_MW,
VAR_MAIN_H, VAR_MH,
VAR_OVERLAY_W, VAR_OW,
VAR_OVERLAY_H, VAR_OH,
VAR_HSUB,
VAR_VSUB,
VAR_X,
VAR_Y,
VAR_N,
VAR_POS,
VAR_T,
VAR_VARS_NB
};
enum EOFAction {
EOF_ACTION_REPEAT,
EOF_ACTION_ENDALL,
EOF_ACTION_PASS
};
static const char * const eof_action_str[] = {
"repeat", "endall", "pass"
};
#define MAIN 0
#define OVERLAY 1
#define R 0
#define G 1
#define B 2
#define A 3
#define Y 0
#define U 1
#define V 2
enum EvalMode {
EVAL_MODE_INIT,
EVAL_MODE_FRAME,
EVAL_MODE_NB
};
enum OverlayFormat {
OVERLAY_FORMAT_YUV420,
OVERLAY_FORMAT_YUV422,
OVERLAY_FORMAT_YUV444,
OVERLAY_FORMAT_RGB,
OVERLAY_FORMAT_GBRP,
OVERLAY_FORMAT_AUTO,
OVERLAY_FORMAT_NB
};
typedef struct OverlayContext {
const AVClass *class;
int x, y; ///< position of overlaid picture
uint8_t main_is_packed_rgb;
uint8_t main_rgba_map[4];
uint8_t main_has_alpha;
uint8_t overlay_is_packed_rgb;
uint8_t overlay_rgba_map[4];
uint8_t overlay_has_alpha;
int format; ///< OverlayFormat
int eval_mode; ///< EvalMode
FFFrameSync fs;
int main_pix_step[4]; ///< steps per pixel for each plane of the main output
int overlay_pix_step[4]; ///< steps per pixel for each plane of the overlay
int hsub, vsub; ///< chroma subsampling values
const AVPixFmtDescriptor *main_desc; ///< format descriptor for main input
double var_values[VAR_VARS_NB];
char *x_expr, *y_expr;
int eof_action; ///< action to take on EOF from source
int opt_shortest;
int opt_repeatlast;
AVExpr *x_pexpr, *y_pexpr;
void (*blend_image)(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y);
} OverlayContext;
static av_cold void uninit(AVFilterContext *ctx)
{
OverlayContext *s = ctx->priv;
ff_framesync2_uninit(&s->fs);
av_expr_free(s->x_pexpr); s->x_pexpr = NULL;
av_expr_free(s->y_pexpr); s->y_pexpr = NULL;
}
static inline int normalize_xy(double d, int chroma_sub)
{
if (isnan(d))
return INT_MAX;
return (int)d & ~((1 << chroma_sub) - 1);
}
static void eval_expr(AVFilterContext *ctx)
{
OverlayContext *s = ctx->priv;
s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, NULL);
s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
s->x = normalize_xy(s->var_values[VAR_X], s->hsub);
s->y = normalize_xy(s->var_values[VAR_Y], s->vsub);
}
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 evaluating the expression '%s' for %s\n",
expr, option);
*pexpr = old;
return ret;
}
av_expr_free(old);
return 0;
}
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
char *res, int res_len, int flags)
{
OverlayContext *s = ctx->priv;
int ret;
if (!strcmp(cmd, "x"))
ret = set_expr(&s->x_pexpr, args, cmd, ctx);
else if (!strcmp(cmd, "y"))
ret = set_expr(&s->y_pexpr, args, cmd, ctx);
else
ret = AVERROR(ENOSYS);
if (ret < 0)
return ret;
if (s->eval_mode == EVAL_MODE_INIT) {
eval_expr(ctx);
av_log(ctx, AV_LOG_VERBOSE, "x:%f xi:%d y:%f yi:%d\n",
s->var_values[VAR_X], s->x,
s->var_values[VAR_Y], s->y);
}
return ret;
}
static const enum AVPixelFormat alpha_pix_fmts[] = {
AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR, AV_PIX_FMT_RGBA,
AV_PIX_FMT_BGRA, AV_PIX_FMT_GBRAP, AV_PIX_FMT_NONE
};
static int query_formats(AVFilterContext *ctx)
{
OverlayContext *s = ctx->priv;
/* overlay formats contains alpha, for avoiding conversion with alpha information loss */
static const enum AVPixelFormat main_pix_fmts_yuv420[] = {
AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVA420P,
AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
AV_PIX_FMT_NONE
};
static const enum AVPixelFormat overlay_pix_fmts_yuv420[] = {
AV_PIX_FMT_YUVA420P, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat main_pix_fmts_yuv422[] = {
AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat overlay_pix_fmts_yuv422[] = {
AV_PIX_FMT_YUVA422P, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat main_pix_fmts_yuv444[] = {
AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVA444P, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat overlay_pix_fmts_yuv444[] = {
AV_PIX_FMT_YUVA444P, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat main_pix_fmts_gbrp[] = {
AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat overlay_pix_fmts_gbrp[] = {
AV_PIX_FMT_GBRAP, AV_PIX_FMT_NONE
};
static const enum AVPixelFormat main_pix_fmts_rgb[] = {
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_NONE
};
static const enum AVPixelFormat overlay_pix_fmts_rgb[] = {
AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA,
AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA,
AV_PIX_FMT_NONE
};
AVFilterFormats *main_formats = NULL;
AVFilterFormats *overlay_formats = NULL;
int ret;
switch (s->format) {
case OVERLAY_FORMAT_YUV420:
if (!(main_formats = ff_make_format_list(main_pix_fmts_yuv420)) ||
!(overlay_formats = ff_make_format_list(overlay_pix_fmts_yuv420))) {
ret = AVERROR(ENOMEM);
goto fail;
}
break;
case OVERLAY_FORMAT_YUV422:
if (!(main_formats = ff_make_format_list(main_pix_fmts_yuv422)) ||
!(overlay_formats = ff_make_format_list(overlay_pix_fmts_yuv422))) {
ret = AVERROR(ENOMEM);
goto fail;
}
break;
case OVERLAY_FORMAT_YUV444:
if (!(main_formats = ff_make_format_list(main_pix_fmts_yuv444)) ||
!(overlay_formats = ff_make_format_list(overlay_pix_fmts_yuv444))) {
ret = AVERROR(ENOMEM);
goto fail;
}
break;
case OVERLAY_FORMAT_RGB:
if (!(main_formats = ff_make_format_list(main_pix_fmts_rgb)) ||
!(overlay_formats = ff_make_format_list(overlay_pix_fmts_rgb))) {
ret = AVERROR(ENOMEM);
goto fail;
}
break;
case OVERLAY_FORMAT_GBRP:
if (!(main_formats = ff_make_format_list(main_pix_fmts_gbrp)) ||
!(overlay_formats = ff_make_format_list(overlay_pix_fmts_gbrp))) {
ret = AVERROR(ENOMEM);
goto fail;
}
break;
case OVERLAY_FORMAT_AUTO:
if (!(main_formats = ff_make_format_list(alpha_pix_fmts))) {
ret = AVERROR(ENOMEM);
goto fail;
}
break;
default:
av_assert0(0);
}
if (s->format == OVERLAY_FORMAT_AUTO) {
ret = ff_set_common_formats(ctx, main_formats);
if (ret < 0)
goto fail;
} else {
if ((ret = ff_formats_ref(main_formats , &ctx->inputs[MAIN]->out_formats )) < 0 ||
(ret = ff_formats_ref(overlay_formats, &ctx->inputs[OVERLAY]->out_formats)) < 0 ||
(ret = ff_formats_ref(main_formats , &ctx->outputs[MAIN]->in_formats )) < 0)
goto fail;
}
return 0;
fail:
if (main_formats)
av_freep(&main_formats->formats);
av_freep(&main_formats);
if (overlay_formats)
av_freep(&overlay_formats->formats);
av_freep(&overlay_formats);
return ret;
}
static int config_input_overlay(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
OverlayContext *s = inlink->dst->priv;
int ret;
const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
av_image_fill_max_pixsteps(s->overlay_pix_step, NULL, pix_desc);
/* Finish the configuration by evaluating the expressions
now when both inputs are configured. */
s->var_values[VAR_MAIN_W ] = s->var_values[VAR_MW] = ctx->inputs[MAIN ]->w;
s->var_values[VAR_MAIN_H ] = s->var_values[VAR_MH] = ctx->inputs[MAIN ]->h;
s->var_values[VAR_OVERLAY_W] = s->var_values[VAR_OW] = ctx->inputs[OVERLAY]->w;
s->var_values[VAR_OVERLAY_H] = s->var_values[VAR_OH] = ctx->inputs[OVERLAY]->h;
s->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
s->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
s->var_values[VAR_X] = NAN;
s->var_values[VAR_Y] = NAN;
s->var_values[VAR_N] = 0;
s->var_values[VAR_T] = NAN;
s->var_values[VAR_POS] = NAN;
if ((ret = set_expr(&s->x_pexpr, s->x_expr, "x", ctx)) < 0 ||
(ret = set_expr(&s->y_pexpr, s->y_expr, "y", ctx)) < 0)
return ret;
s->overlay_is_packed_rgb =
ff_fill_rgba_map(s->overlay_rgba_map, inlink->format) >= 0;
s->overlay_has_alpha = ff_fmt_is_in(inlink->format, alpha_pix_fmts);
if (s->eval_mode == EVAL_MODE_INIT) {
eval_expr(ctx);
av_log(ctx, AV_LOG_VERBOSE, "x:%f xi:%d y:%f yi:%d\n",
s->var_values[VAR_X], s->x,
s->var_values[VAR_Y], s->y);
}
av_log(ctx, AV_LOG_VERBOSE,
"main w:%d h:%d fmt:%s overlay w:%d h:%d fmt:%s eof_action:%s\n",
ctx->inputs[MAIN]->w, ctx->inputs[MAIN]->h,
av_get_pix_fmt_name(ctx->inputs[MAIN]->format),
ctx->inputs[OVERLAY]->w, ctx->inputs[OVERLAY]->h,
av_get_pix_fmt_name(ctx->inputs[OVERLAY]->format),
eof_action_str[s->eof_action]);
return 0;
}
static int config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
OverlayContext *s = ctx->priv;
int ret;
if ((ret = ff_framesync2_init_dualinput(&s->fs, ctx)) < 0)
return ret;
if (s->opt_shortest)
s->fs.in[0].after = s->fs.in[1].after = EXT_STOP;
if (!s->opt_repeatlast) {
s->fs.in[1].after = EXT_NULL;
s->fs.in[1].sync = 0;
}
outlink->w = ctx->inputs[MAIN]->w;
outlink->h = ctx->inputs[MAIN]->h;
outlink->time_base = ctx->inputs[MAIN]->time_base;
return ff_framesync2_configure(&s->fs);
}
// divide by 255 and round to nearest
// apply a fast variant: (X+127)/255 = ((X+127)*257+257)>>16 = ((X+128)*257)>>16
#define FAST_DIV255(x) ((((x) + 128) * 257) >> 16)
// calculate the unpremultiplied alpha, applying the general equation:
// alpha = alpha_overlay / ( (alpha_main + alpha_overlay) - (alpha_main * alpha_overlay) )
// (((x) << 16) - ((x) << 9) + (x)) is a faster version of: 255 * 255 * x
// ((((x) + (y)) << 8) - ((x) + (y)) - (y) * (x)) is a faster version of: 255 * (x + y)
#define UNPREMULTIPLY_ALPHA(x, y) ((((x) << 16) - ((x) << 9) + (x)) / ((((x) + (y)) << 8) - ((x) + (y)) - (y) * (x)))
/**
* Blend image in src to destination buffer dst at position (x, y).
*/
static void blend_image_packed_rgb(AVFilterContext *ctx,
AVFrame *dst, const AVFrame *src,
int main_has_alpha, int x, int y)
{
OverlayContext *s = ctx->priv;
int i, imax, j, jmax;
const int src_w = src->width;
const int src_h = src->height;
const int dst_w = dst->width;
const int dst_h = dst->height;
uint8_t alpha; ///< the amount of overlay to blend on to main
const int dr = s->main_rgba_map[R];
const int dg = s->main_rgba_map[G];
const int db = s->main_rgba_map[B];
const int da = s->main_rgba_map[A];
const int dstep = s->main_pix_step[0];
const int sr = s->overlay_rgba_map[R];
const int sg = s->overlay_rgba_map[G];
const int sb = s->overlay_rgba_map[B];
const int sa = s->overlay_rgba_map[A];
const int sstep = s->overlay_pix_step[0];
uint8_t *S, *sp, *d, *dp;
i = FFMAX(-y, 0);
sp = src->data[0] + i * src->linesize[0];
dp = dst->data[0] + (y+i) * dst->linesize[0];
for (imax = FFMIN(-y + dst_h, src_h); i < imax; i++) {
j = FFMAX(-x, 0);
S = sp + j * sstep;
d = dp + (x+j) * dstep;
for (jmax = FFMIN(-x + dst_w, src_w); j < jmax; j++) {
alpha = S[sa];
// if the main channel has an alpha channel, alpha has to be calculated
// to create an un-premultiplied (straight) alpha value
if (main_has_alpha && alpha != 0 && alpha != 255) {
uint8_t alpha_d = d[da];
alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
}
switch (alpha) {
case 0:
break;
case 255:
d[dr] = S[sr];
d[dg] = S[sg];
d[db] = S[sb];
break;
default:
// main_value = main_value * (1 - alpha) + overlay_value * alpha
// since alpha is in the range 0-255, the result must divided by 255
d[dr] = FAST_DIV255(d[dr] * (255 - alpha) + S[sr] * alpha);
d[dg] = FAST_DIV255(d[dg] * (255 - alpha) + S[sg] * alpha);
d[db] = FAST_DIV255(d[db] * (255 - alpha) + S[sb] * alpha);
}
if (main_has_alpha) {
switch (alpha) {
case 0:
break;
case 255:
d[da] = S[sa];
break;
default:
// apply alpha compositing: main_alpha += (1-main_alpha) * overlay_alpha
d[da] += FAST_DIV255((255 - d[da]) * S[sa]);
}
}
d += dstep;
S += sstep;
}
dp += dst->linesize[0];
sp += src->linesize[0];
}
}
static av_always_inline void blend_plane(AVFilterContext *ctx,
AVFrame *dst, const AVFrame *src,
int src_w, int src_h,
int dst_w, int dst_h,
int i, int hsub, int vsub,
int x, int y,
int main_has_alpha,
int dst_plane,
int dst_offset,
int dst_step)
{
int src_wp = AV_CEIL_RSHIFT(src_w, hsub);
int src_hp = AV_CEIL_RSHIFT(src_h, vsub);
int dst_wp = AV_CEIL_RSHIFT(dst_w, hsub);
int dst_hp = AV_CEIL_RSHIFT(dst_h, vsub);
int yp = y>>vsub;
int xp = x>>hsub;
uint8_t *s, *sp, *d, *dp, *dap, *a, *da, *ap;
int jmax, j, k, kmax;
j = FFMAX(-yp, 0);
sp = src->data[i] + j * src->linesize[i];
dp = dst->data[dst_plane]
+ (yp+j) * dst->linesize[dst_plane]
+ dst_offset;
ap = src->data[3] + (j<<vsub) * src->linesize[3];
dap = dst->data[3] + ((yp+j) << vsub) * dst->linesize[3];
for (jmax = FFMIN(-yp + dst_hp, src_hp); j < jmax; j++) {
k = FFMAX(-xp, 0);
d = dp + (xp+k) * dst_step;
s = sp + k;
a = ap + (k<<hsub);
da = dap + ((xp+k) << hsub);
for (kmax = FFMIN(-xp + dst_wp, src_wp); k < kmax; k++) {
int alpha_v, alpha_h, alpha;
// average alpha for color components, improve quality
if (hsub && vsub && j+1 < src_hp && k+1 < src_wp) {
alpha = (a[0] + a[src->linesize[3]] +
a[1] + a[src->linesize[3]+1]) >> 2;
} else if (hsub || vsub) {
alpha_h = hsub && k+1 < src_wp ?
(a[0] + a[1]) >> 1 : a[0];
alpha_v = vsub && j+1 < src_hp ?
(a[0] + a[src->linesize[3]]) >> 1 : a[0];
alpha = (alpha_v + alpha_h) >> 1;
} else
alpha = a[0];
// if the main channel has an alpha channel, alpha has to be calculated
// to create an un-premultiplied (straight) alpha value
if (main_has_alpha && alpha != 0 && alpha != 255) {
// average alpha for color components, improve quality
uint8_t alpha_d;
if (hsub && vsub && j+1 < src_hp && k+1 < src_wp) {
alpha_d = (da[0] + da[dst->linesize[3]] +
da[1] + da[dst->linesize[3]+1]) >> 2;
} else if (hsub || vsub) {
alpha_h = hsub && k+1 < src_wp ?
(da[0] + da[1]) >> 1 : da[0];
alpha_v = vsub && j+1 < src_hp ?
(da[0] + da[dst->linesize[3]]) >> 1 : da[0];
alpha_d = (alpha_v + alpha_h) >> 1;
} else
alpha_d = da[0];
alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
}
*d = FAST_DIV255(*d * (255 - alpha) + *s * alpha);
s++;
d += dst_step;
da += 1 << hsub;
a += 1 << hsub;
}
dp += dst->linesize[dst_plane];
sp += src->linesize[i];
ap += (1 << vsub) * src->linesize[3];
dap += (1 << vsub) * dst->linesize[3];
}
}
static inline void alpha_composite(const AVFrame *src, const AVFrame *dst,
int src_w, int src_h,
int dst_w, int dst_h,
int x, int y)
{
uint8_t alpha; ///< the amount of overlay to blend on to main
uint8_t *s, *sa, *d, *da;
int i, imax, j, jmax;
i = FFMAX(-y, 0);
sa = src->data[3] + i * src->linesize[3];
da = dst->data[3] + (y+i) * dst->linesize[3];
for (imax = FFMIN(-y + dst_h, src_h); i < imax; i++) {
j = FFMAX(-x, 0);
s = sa + j;
d = da + x+j;
for (jmax = FFMIN(-x + dst_w, src_w); j < jmax; j++) {
alpha = *s;
if (alpha != 0 && alpha != 255) {
uint8_t alpha_d = *d;
alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
}
switch (alpha) {
case 0:
break;
case 255:
*d = *s;
break;
default:
// apply alpha compositing: main_alpha += (1-main_alpha) * overlay_alpha
*d += FAST_DIV255((255 - *d) * *s);
}
d += 1;
s += 1;
}
da += dst->linesize[3];
sa += src->linesize[3];
}
}
static av_always_inline void blend_image_yuv(AVFilterContext *ctx,
AVFrame *dst, const AVFrame *src,
int hsub, int vsub,
int main_has_alpha,
int x, int y)
{
OverlayContext *s = ctx->priv;
const int src_w = src->width;
const int src_h = src->height;
const int dst_w = dst->width;
const int dst_h = dst->height;
blend_plane(ctx, dst, src, src_w, src_h, dst_w, dst_h, 0, 0, 0, x, y, main_has_alpha,
s->main_desc->comp[0].plane, s->main_desc->comp[0].offset, s->main_desc->comp[0].step);
blend_plane(ctx, dst, src, src_w, src_h, dst_w, dst_h, 1, hsub, vsub, x, y, main_has_alpha,
s->main_desc->comp[1].plane, s->main_desc->comp[1].offset, s->main_desc->comp[1].step);
blend_plane(ctx, dst, src, src_w, src_h, dst_w, dst_h, 2, hsub, vsub, x, y, main_has_alpha,
s->main_desc->comp[2].plane, s->main_desc->comp[2].offset, s->main_desc->comp[2].step);
if (main_has_alpha)
alpha_composite(src, dst, src_w, src_h, dst_w, dst_h, x, y);
}
static av_always_inline void blend_image_planar_rgb(AVFilterContext *ctx,
AVFrame *dst, const AVFrame *src,
int hsub, int vsub,
int main_has_alpha,
int x, int y)
{
OverlayContext *s = ctx->priv;
const int src_w = src->width;
const int src_h = src->height;
const int dst_w = dst->width;
const int dst_h = dst->height;
blend_plane(ctx, dst, src, src_w, src_h, dst_w, dst_h, 0, 0, 0, x, y, main_has_alpha,
s->main_desc->comp[1].plane, s->main_desc->comp[1].offset, s->main_desc->comp[1].step);
blend_plane(ctx, dst, src, src_w, src_h, dst_w, dst_h, 1, hsub, vsub, x, y, main_has_alpha,
s->main_desc->comp[2].plane, s->main_desc->comp[2].offset, s->main_desc->comp[2].step);
blend_plane(ctx, dst, src, src_w, src_h, dst_w, dst_h, 2, hsub, vsub, x, y, main_has_alpha,
s->main_desc->comp[0].plane, s->main_desc->comp[0].offset, s->main_desc->comp[0].step);
if (main_has_alpha)
alpha_composite(src, dst, src_w, src_h, dst_w, dst_h, x, y);
}
static void blend_image_yuv420(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_yuv(ctx, dst, src, 1, 1, 0, x, y);
}
static void blend_image_yuva420(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_yuv(ctx, dst, src, 1, 1, 1, x, y);
}
static void blend_image_yuv422(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_yuv(ctx, dst, src, 1, 0, 0, x, y);
}
static void blend_image_yuva422(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_yuv(ctx, dst, src, 1, 0, 1, x, y);
}
static void blend_image_yuv444(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_yuv(ctx, dst, src, 0, 0, 0, x, y);
}
static void blend_image_yuva444(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_yuv(ctx, dst, src, 0, 0, 1, x, y);
}
static void blend_image_gbrp(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_planar_rgb(ctx, dst, src, 0, 0, 0, x, y);
}
static void blend_image_gbrap(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_planar_rgb(ctx, dst, src, 0, 0, 1, x, y);
}
static void blend_image_rgb(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_packed_rgb(ctx, dst, src, 0, x, y);
}
static void blend_image_rgba(AVFilterContext *ctx, AVFrame *dst, const AVFrame *src, int x, int y)
{
blend_image_packed_rgb(ctx, dst, src, 1, x, y);
}
static int config_input_main(AVFilterLink *inlink)
{
OverlayContext *s = inlink->dst->priv;
const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
av_image_fill_max_pixsteps(s->main_pix_step, NULL, pix_desc);
s->hsub = pix_desc->log2_chroma_w;
s->vsub = pix_desc->log2_chroma_h;
s->main_desc = pix_desc;
s->main_is_packed_rgb =
ff_fill_rgba_map(s->main_rgba_map, inlink->format) >= 0;
s->main_has_alpha = ff_fmt_is_in(inlink->format, alpha_pix_fmts);
switch (s->format) {
case OVERLAY_FORMAT_YUV420:
s->blend_image = s->main_has_alpha ? blend_image_yuva420 : blend_image_yuv420;
break;
case OVERLAY_FORMAT_YUV422:
s->blend_image = s->main_has_alpha ? blend_image_yuva422 : blend_image_yuv422;
break;
case OVERLAY_FORMAT_YUV444:
s->blend_image = s->main_has_alpha ? blend_image_yuva444 : blend_image_yuv444;
break;
case OVERLAY_FORMAT_RGB:
s->blend_image = s->main_has_alpha ? blend_image_rgba : blend_image_rgb;
break;
case OVERLAY_FORMAT_GBRP:
s->blend_image = s->main_has_alpha ? blend_image_gbrap : blend_image_gbrp;
break;
case OVERLAY_FORMAT_AUTO:
switch (inlink->format) {
case AV_PIX_FMT_YUVA420P:
s->blend_image = blend_image_yuva420;
break;
case AV_PIX_FMT_YUVA422P:
s->blend_image = blend_image_yuva422;
break;
case AV_PIX_FMT_YUVA444P:
s->blend_image = blend_image_yuva444;
break;
case AV_PIX_FMT_ARGB:
case AV_PIX_FMT_RGBA:
case AV_PIX_FMT_BGRA:
case AV_PIX_FMT_ABGR:
s->blend_image = blend_image_rgba;
break;
case AV_PIX_FMT_GBRAP:
s->blend_image = blend_image_gbrap;
break;
default:
av_assert0(0);
break;
}
break;
}
return 0;
}
static int do_blend(FFFrameSync *fs)
{
AVFilterContext *ctx = fs->parent;
AVFrame *mainpic, *second;
OverlayContext *s = ctx->priv;
AVFilterLink *inlink = ctx->inputs[0];
int ret;
ret = ff_framesync2_dualinput_get_writable(fs, &mainpic, &second);
if (ret < 0)
return ret;
if (!second)
return ff_filter_frame(ctx->outputs[0], mainpic);
if (s->eval_mode == EVAL_MODE_FRAME) {
int64_t pos = mainpic->pkt_pos;
s->var_values[VAR_N] = inlink->frame_count_out;
s->var_values[VAR_T] = mainpic->pts == AV_NOPTS_VALUE ?
NAN : mainpic->pts * av_q2d(inlink->time_base);
s->var_values[VAR_POS] = pos == -1 ? NAN : pos;
s->var_values[VAR_OVERLAY_W] = s->var_values[VAR_OW] = second->width;
s->var_values[VAR_OVERLAY_H] = s->var_values[VAR_OH] = second->height;
s->var_values[VAR_MAIN_W ] = s->var_values[VAR_MW] = mainpic->width;
s->var_values[VAR_MAIN_H ] = s->var_values[VAR_MH] = mainpic->height;
eval_expr(ctx);
av_log(ctx, AV_LOG_DEBUG, "n:%f t:%f pos:%f x:%f xi:%d y:%f yi:%d\n",
s->var_values[VAR_N], s->var_values[VAR_T], s->var_values[VAR_POS],
s->var_values[VAR_X], s->x,
s->var_values[VAR_Y], s->y);
}
if (s->x < mainpic->width && s->x + second->width >= 0 ||
s->y < mainpic->height && s->y + second->height >= 0)
s->blend_image(ctx, mainpic, second, s->x, s->y);
return ff_filter_frame(ctx->outputs[0], mainpic);
}
static av_cold int init(AVFilterContext *ctx)
{
OverlayContext *s = ctx->priv;
if (!s->opt_repeatlast || s->eof_action == EOF_ACTION_PASS) {
s->opt_repeatlast = 0;
s->eof_action = EOF_ACTION_PASS;
}
if (s->opt_shortest || s->eof_action == EOF_ACTION_ENDALL) {
s->opt_shortest = 1;
s->eof_action = EOF_ACTION_ENDALL;
}
s->fs.on_event = do_blend;
return 0;
}
static int activate(AVFilterContext *ctx)
{
OverlayContext *s = ctx->priv;
return ff_framesync2_activate(&s->fs);
}
#define OFFSET(x) offsetof(OverlayContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption overlay_options[] = {
{ "x", "set the x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "y", "set the y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "eof_action", "Action to take when encountering EOF from secondary input ",
OFFSET(eof_action), AV_OPT_TYPE_INT, { .i64 = EOF_ACTION_REPEAT },
EOF_ACTION_REPEAT, EOF_ACTION_PASS, .flags = FLAGS, "eof_action" },
{ "repeat", "Repeat the previous frame.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_REPEAT }, .flags = FLAGS, "eof_action" },
{ "endall", "End both streams.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_ENDALL }, .flags = FLAGS, "eof_action" },
{ "pass", "Pass through the main input.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_PASS }, .flags = FLAGS, "eof_action" },
{ "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_FRAME}, 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" },
{ "shortest", "force termination when the shortest input terminates", OFFSET(opt_shortest), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
{ "format", "set output format", OFFSET(format), AV_OPT_TYPE_INT, {.i64=OVERLAY_FORMAT_YUV420}, 0, OVERLAY_FORMAT_NB-1, FLAGS, "format" },
{ "yuv420", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_YUV420}, .flags = FLAGS, .unit = "format" },
{ "yuv422", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_YUV422}, .flags = FLAGS, .unit = "format" },
{ "yuv444", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_YUV444}, .flags = FLAGS, .unit = "format" },
{ "rgb", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_RGB}, .flags = FLAGS, .unit = "format" },
{ "gbrp", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_GBRP}, .flags = FLAGS, .unit = "format" },
{ "auto", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_AUTO}, .flags = FLAGS, .unit = "format" },
{ "repeatlast", "repeat overlay of the last overlay frame", OFFSET(opt_repeatlast), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(overlay);
static const AVFilterPad avfilter_vf_overlay_inputs[] = {
{
.name = "main",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_input_main,
},
{
.name = "overlay",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_input_overlay,
},
{ NULL }
};
static const AVFilterPad avfilter_vf_overlay_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
{ NULL }
};
AVFilter ff_vf_overlay = {
.name = "overlay",
.description = NULL_IF_CONFIG_SMALL("Overlay a video source on top of the input."),
.init = init,
.uninit = uninit,
.priv_size = sizeof(OverlayContext),
.priv_class = &overlay_class,
.query_formats = query_formats,
.activate = activate,
.process_command = process_command,
.inputs = avfilter_vf_overlay_inputs,
.outputs = avfilter_vf_overlay_outputs,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
};
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