FFmpeg/libavfilter/vf_mix.c
Paul B Mahol ec5328aa6f avfilter: add mix filter
Signed-off-by: Paul B Mahol <onemda@gmail.com>
2017-11-24 16:51:33 +01:00

284 lines
8.2 KiB
C

/*
* Copyright (c) 2017 Paul B Mahol
*
* 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/avstring.h"
#include "libavutil/imgutils.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "framesync.h"
#include "video.h"
typedef struct MixContext {
const AVClass *class;
const AVPixFmtDescriptor *desc;
char *weights_str;
int nb_inputs;
int duration;
float *weights;
float wfactor;
int depth;
int nb_planes;
int linesize[4];
int height[4];
AVFrame **frames;
FFFrameSync fs;
} MixContext;
static int query_formats(AVFilterContext *ctx)
{
AVFilterFormats *pix_fmts = NULL;
int fmt, ret;
for (fmt = 0; av_pix_fmt_desc_get(fmt); fmt++) {
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
if (!(desc->flags & AV_PIX_FMT_FLAG_PAL ||
desc->flags & AV_PIX_FMT_FLAG_HWACCEL ||
desc->flags & AV_PIX_FMT_FLAG_BITSTREAM) &&
(ret = ff_add_format(&pix_fmts, fmt)) < 0)
return ret;
}
return ff_set_common_formats(ctx, pix_fmts);
}
static av_cold int init(AVFilterContext *ctx)
{
MixContext *s = ctx->priv;
char *p, *arg, *saveptr = NULL;
int i, ret;
s->frames = av_calloc(s->nb_inputs, sizeof(*s->frames));
if (!s->frames)
return AVERROR(ENOMEM);
s->weights = av_calloc(s->nb_inputs, sizeof(*s->weights));
if (!s->weights)
return AVERROR(ENOMEM);
for (i = 0; i < s->nb_inputs; i++) {
AVFilterPad pad = { 0 };
pad.type = AVMEDIA_TYPE_VIDEO;
pad.name = av_asprintf("input%d", i);
if (!pad.name)
return AVERROR(ENOMEM);
if ((ret = ff_insert_inpad(ctx, i, &pad)) < 0) {
av_freep(&pad.name);
return ret;
}
}
p = s->weights_str;
for (i = 0; i < s->nb_inputs; i++) {
if (!(arg = av_strtok(p, " ", &saveptr)))
break;
p = NULL;
sscanf(arg, "%f", &s->weights[i]);
s->wfactor += s->weights[i];
}
s->wfactor = 1 / s->wfactor;
return 0;
}
static int process_frame(FFFrameSync *fs)
{
AVFilterContext *ctx = fs->parent;
AVFilterLink *outlink = ctx->outputs[0];
MixContext *s = fs->opaque;
AVFrame **in = s->frames;
AVFrame *out;
int i, p, ret, x, y;
for (i = 0; i < s->nb_inputs; i++) {
if ((ret = ff_framesync_get_frame(&s->fs, i, &in[i], 0)) < 0)
return ret;
}
out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!out)
return AVERROR(ENOMEM);
out->pts = av_rescale_q(s->fs.pts, s->fs.time_base, outlink->time_base);
if (s->depth <= 8) {
for (p = 0; p < s->nb_planes; p++) {
uint8_t *dst = out->data[p];
for (y = 0; y < s->height[p]; y++) {
for (x = 0; x < s->linesize[p]; x++) {
int val = 0;
for (i = 0; i < s->nb_inputs; i++) {
uint8_t src = in[i]->data[p][y * s->linesize[p] + x];
val += src * s->weights[i];
}
dst[x] = val * s->wfactor;
}
dst += out->linesize[p];
}
}
} else {
for (p = 0; p < s->nb_planes; p++) {
uint16_t *dst = (uint16_t *)out->data[p];
for (y = 0; y < s->height[p]; y++) {
for (x = 0; x < s->linesize[p]; x++) {
int val = 0;
for (i = 0; i < s->nb_inputs; i++) {
uint16_t src = AV_RN16(in[i]->data[p] + y * s->linesize[p] + x * 2);
val += src * s->weights[i];
}
dst[x] = val * s->wfactor;
}
dst += out->linesize[p] / 2;
}
}
}
return ff_filter_frame(outlink, out);
}
static int config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
MixContext *s = ctx->priv;
AVRational time_base = ctx->inputs[0]->time_base;
AVRational frame_rate = ctx->inputs[0]->frame_rate;
AVFilterLink *inlink = ctx->inputs[0];
int height = ctx->inputs[0]->h;
int width = ctx->inputs[0]->w;
FFFrameSyncIn *in;
int i, ret;
for (i = 1; i < s->nb_inputs; i++) {
if (ctx->inputs[i]->h != height || ctx->inputs[i]->w != width) {
av_log(ctx, AV_LOG_ERROR, "Input %d size (%dx%d) does not match input %d size (%dx%d).\n", i, ctx->inputs[i]->w, ctx->inputs[i]->h, 0, width, height);
return AVERROR(EINVAL);
}
}
s->desc = av_pix_fmt_desc_get(outlink->format);
if (!s->desc)
return AVERROR_BUG;
s->nb_planes = av_pix_fmt_count_planes(outlink->format);
s->depth = s->desc->comp[0].depth;
outlink->w = width;
outlink->h = height;
outlink->time_base = time_base;
outlink->frame_rate = frame_rate;
if ((ret = ff_framesync_init(&s->fs, ctx, s->nb_inputs)) < 0)
return ret;
in = s->fs.in;
s->fs.opaque = s;
s->fs.on_event = process_frame;
if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
return ret;
s->height[1] = s->height[2] = AV_CEIL_RSHIFT(inlink->h, s->desc->log2_chroma_h);
s->height[0] = s->height[3] = inlink->h;
for (i = 0; i < s->nb_inputs; i++) {
AVFilterLink *inlink = ctx->inputs[i];
in[i].time_base = inlink->time_base;
in[i].sync = 1;
in[i].before = EXT_STOP;
in[i].after = (s->duration == 1 || (s->duration == 2 && i == 0)) ? EXT_STOP : EXT_INFINITY;
}
return ff_framesync_configure(&s->fs);
}
static av_cold void uninit(AVFilterContext *ctx)
{
MixContext *s = ctx->priv;
int i;
ff_framesync_uninit(&s->fs);
av_freep(&s->frames);
av_freep(&s->weights);
for (i = 0; i < ctx->nb_inputs; i++)
av_freep(&ctx->input_pads[i].name);
}
static int activate(AVFilterContext *ctx)
{
MixContext *s = ctx->priv;
return ff_framesync_activate(&s->fs);
}
#define OFFSET(x) offsetof(MixContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
static const AVOption mix_options[] = {
{ "inputs", "set number of inputs", OFFSET(nb_inputs), AV_OPT_TYPE_INT, {.i64=2}, 2, INT_MAX, .flags = FLAGS },
{ "weights", "set weight for each input", OFFSET(weights_str), AV_OPT_TYPE_STRING, {.str="1 1"}, 0, 0, .flags = FLAGS },
{ "duration", "how to determine end of stream", OFFSET(duration), AV_OPT_TYPE_INT, {.i64=0}, 0, 2, .flags = FLAGS, "duration" },
{ "longest", "Duration of longest input", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "duration" },
{ "shortest", "Duration of shortest input", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "duration" },
{ "first", "Duration of first input", 0, AV_OPT_TYPE_CONST, {.i64=2}, 0, 0, FLAGS, "duration" },
{ NULL },
};
static const AVFilterPad outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
{ NULL }
};
AVFILTER_DEFINE_CLASS(mix);
AVFilter ff_vf_mix = {
.name = "mix",
.description = NULL_IF_CONFIG_SMALL("Mix video inputs."),
.priv_size = sizeof(MixContext),
.priv_class = &mix_class,
.query_formats = query_formats,
.outputs = outputs,
.init = init,
.uninit = uninit,
.activate = activate,
.flags = AVFILTER_FLAG_DYNAMIC_INPUTS,
};