/* * Copyright (c) 2018 Marton Balint * * 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 "config_components.h" #include "libavutil/opt.h"#include "libavutil/time.h"#include "audio.h"#include "avfilter.h"#include "filters.h"#include "video.h" typedef struct CueContext {    const AVClass *class;    int64_t first_pts;    int64_t cue;    int64_t preroll;    int64_t buffer;    int status;} CueContext; static int activate(AVFilterContext *ctx){    AVFilterLink *inlink = ctx->inputs[0];    AVFilterLink *outlink = ctx->outputs[0];    CueContext *s = ctx->priv;     FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);     if (ff_inlink_queued_frames(inlink)) {        AVFrame *frame = ff_inlink_peek_frame(inlink, 0);        int64_t pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q);         if (!s->status) {            s->first_pts = pts;            s->status++;        }        if (s->status == 1) {            if (pts - s->first_pts < s->preroll) {                int ret = ff_inlink_consume_frame(inlink, &frame);                if (ret < 0)                    return ret;                return ff_filter_frame(outlink, frame);            }            s->first_pts = pts;            s->status++;        }        if (s->status == 2) {            frame = ff_inlink_peek_frame(inlink, ff_inlink_queued_frames(inlink) - 1);            pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q);            if (!(pts - s->first_pts < s->buffer && (av_gettime() - s->cue) < 0))                s->status++;        }        if (s->status == 3) {            int64_t diff;            while ((diff = (av_gettime() - s->cue)) < 0)                av_usleep(av_clip(-diff / 2, 100, 1000000));            s->status++;        }        if (s->status == 4) {            int ret = ff_inlink_consume_frame(inlink, &frame);            if (ret < 0)                return ret;            return ff_filter_frame(outlink, frame);        }    }     FF_FILTER_FORWARD_STATUS(inlink, outlink);    FF_FILTER_FORWARD_WANTED(outlink, inlink);     return FFERROR_NOT_READY;} #define OFFSET(x) offsetof(CueContext, x)#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAMstatic const AVOption options[] = {    { "cue", "cue unix timestamp in microseconds", OFFSET(cue), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT64_MAX, FLAGS },    { "preroll", "preroll duration in seconds", OFFSET(preroll), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },    { "buffer", "buffer duration in seconds", OFFSET(buffer), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },    { NULL }}; AVFILTER_DEFINE_CLASS_EXT(cue_acue, "(a)cue", options); #if CONFIG_CUE_FILTERconst FFFilter ff_vf_cue = {    .p.name        = "cue",    .p.description = NULL_IF_CONFIG_SMALL("Delay filtering to match a cue."),    .p.priv_class  = &cue_acue_class,    .priv_size   = sizeof(CueContext),    FILTER_INPUTS(ff_video_default_filterpad),    FILTER_OUTPUTS(ff_video_default_filterpad),    .activate    = activate,};#endif /* CONFIG_CUE_FILTER */ #if CONFIG_ACUE_FILTERconst FFFilter ff_af_acue = {    .p.name        = "acue",    .p.description = NULL_IF_CONFIG_SMALL("Delay filtering to match a cue."),    .p.priv_class  = &cue_acue_class,    .p.flags       = AVFILTER_FLAG_METADATA_ONLY,    .priv_size   = sizeof(CueContext),    FILTER_INPUTS(ff_audio_default_filterpad),    FILTER_OUTPUTS(ff_audio_default_filterpad),    .activate    = activate,};#endif /* CONFIG_ACUE_FILTER */