/* * Copyright (c) 2016 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/audio_fifo.h"#include "libavutil/avassert.h"#include "libavutil/fifo.h"#include "libavutil/internal.h"#include "libavutil/opt.h"#include "avfilter.h"#include "audio.h"#include "formats.h"#include "internal.h"#include "video.h" typedef struct LoopContext {    const AVClass *class;     AVAudioFifo *fifo;    AVAudioFifo *left;    AVFrame **frames;    int nb_frames;    int current_frame;    int64_t start_pts;    int64_t duration;    int64_t current_sample;    int64_t nb_samples;    int64_t ignored_samples;     int loop;    int64_t size;    int64_t start;    int64_t pts;} LoopContext; #define AFLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM#define VFLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM#define OFFSET(x) offsetof(LoopContext, x) #if CONFIG_ALOOP_FILTER static int aconfig_input(AVFilterLink *inlink){    AVFilterContext *ctx = inlink->dst;    LoopContext *s  = ctx->priv;     s->fifo = av_audio_fifo_alloc(inlink->format, inlink->channels, 8192);    s->left = av_audio_fifo_alloc(inlink->format, inlink->channels, 8192);    if (!s->fifo || !s->left)        return AVERROR(ENOMEM);     return 0;} static av_cold void auninit(AVFilterContext *ctx){    LoopContext *s = ctx->priv;     av_audio_fifo_free(s->fifo);    av_audio_fifo_free(s->left);} static int push_samples(AVFilterContext *ctx, int nb_samples){    AVFilterLink *outlink = ctx->outputs[0];    LoopContext *s = ctx->priv;    AVFrame *out;    int ret, i = 0;     while (s->loop != 0 && i < nb_samples) {        out = ff_get_audio_buffer(outlink, FFMIN(nb_samples, s->nb_samples - s->current_sample));        if (!out)            return AVERROR(ENOMEM);        ret = av_audio_fifo_peek_at(s->fifo, (void **)out->extended_data, out->nb_samples, s->current_sample);        if (ret < 0) {            av_frame_free(&out);            return ret;        }        out->pts = s->pts;        out->nb_samples = ret;        s->pts += out->nb_samples;        i += out->nb_samples;        s->current_sample += out->nb_samples;         ret = ff_filter_frame(outlink, out);        if (ret < 0)            return ret;         if (s->current_sample >= s->nb_samples) {            s->current_sample = 0;             if (s->loop > 0)                s->loop--;        }    }     return ret;} static int afilter_frame(AVFilterLink *inlink, AVFrame *frame){    AVFilterContext *ctx = inlink->dst;    AVFilterLink *outlink = ctx->outputs[0];    LoopContext *s = ctx->priv;    int ret = 0;     if (s->ignored_samples + frame->nb_samples > s->start && s->size > 0 && s->loop != 0) {        if (s->nb_samples < s->size) {            int written = FFMIN(frame->nb_samples, s->size - s->nb_samples);            int drain = 0;             ret = av_audio_fifo_write(s->fifo, (void **)frame->extended_data, written);            if (ret < 0)                return ret;            if (!s->nb_samples) {                drain = FFMAX(0, s->start - s->ignored_samples);                s->pts = frame->pts;                av_audio_fifo_drain(s->fifo, drain);                s->pts += s->start - s->ignored_samples;            }            s->nb_samples += ret - drain;            drain = frame->nb_samples - written;            if (s->nb_samples == s->size && drain > 0) {                int ret2;                 ret2 = av_audio_fifo_write(s->left, (void **)frame->extended_data, frame->nb_samples);                if (ret2 < 0)                   return ret2;                av_audio_fifo_drain(s->left, drain);            }            frame->nb_samples = ret;            s->pts += ret;            ret = ff_filter_frame(outlink, frame);        } else {            int nb_samples = frame->nb_samples;             av_frame_free(&frame);            ret = push_samples(ctx, nb_samples);        }    } else {        s->ignored_samples += frame->nb_samples;        frame->pts = s->pts;        s->pts += frame->nb_samples;        ret = ff_filter_frame(outlink, frame);    }     return ret;} static int arequest_frame(AVFilterLink *outlink){    AVFilterContext *ctx = outlink->src;    LoopContext *s = ctx->priv;    int ret = 0;     if ((!s->size) ||        (s->nb_samples < s->size) ||        (s->nb_samples >= s->size && s->loop == 0)) {        int nb_samples = av_audio_fifo_size(s->left);         if (s->loop == 0 && nb_samples > 0) {            AVFrame *out;             out = ff_get_audio_buffer(outlink, nb_samples);            if (!out)                return AVERROR(ENOMEM);            av_audio_fifo_read(s->left, (void **)out->extended_data, nb_samples);            out->pts = s->pts;            s->pts += nb_samples;            ret = ff_filter_frame(outlink, out);            if (ret < 0)                return ret;        }        ret = ff_request_frame(ctx->inputs[0]);    } else {        ret = push_samples(ctx, 1024);    }     if (ret == AVERROR_EOF && s->nb_samples > 0 && s->loop != 0) {        ret = push_samples(ctx, outlink->sample_rate);    }     return ret;} static const AVOption aloop_options[] = {    { "loop",  "number of loops",               OFFSET(loop),  AV_OPT_TYPE_INT,   {.i64 = 0 }, -1, INT_MAX,   AFLAGS },    { "size",  "max number of samples to loop", OFFSET(size),  AV_OPT_TYPE_INT64, {.i64 = 0 },  0, INT32_MAX, AFLAGS },    { "start", "set the loop start sample",     OFFSET(start), AV_OPT_TYPE_INT64, {.i64 = 0 },  0, INT64_MAX, AFLAGS },    { NULL }}; AVFILTER_DEFINE_CLASS(aloop); static const AVFilterPad ainputs[] = {    {        .name         = "default",        .type         = AVMEDIA_TYPE_AUDIO,        .filter_frame = afilter_frame,        .config_props = aconfig_input,    },    { NULL }}; static const AVFilterPad aoutputs[] = {    {        .name          = "default",        .type          = AVMEDIA_TYPE_AUDIO,        .request_frame = arequest_frame,    },    { NULL }}; AVFilter ff_af_aloop = {    .name          = "aloop",    .description   = NULL_IF_CONFIG_SMALL("Loop audio samples."),    .priv_size     = sizeof(LoopContext),    .priv_class    = &aloop_class,    .uninit        = auninit,    .inputs        = ainputs,    .outputs       = aoutputs,};#endif /* CONFIG_ALOOP_FILTER */ #if CONFIG_LOOP_FILTER static av_cold int init(AVFilterContext *ctx){    LoopContext *s = ctx->priv;     s->frames = av_calloc(s->size, sizeof(*s->frames));    if (!s->frames)        return AVERROR(ENOMEM);     return 0;} static av_cold void uninit(AVFilterContext *ctx){    LoopContext *s = ctx->priv;    int i;     for (i = 0; i < s->nb_frames; i++)        av_frame_free(&s->frames[i]);     av_freep(&s->frames);    s->nb_frames = 0;} static int push_frame(AVFilterContext *ctx){    AVFilterLink *outlink = ctx->outputs[0];    LoopContext *s = ctx->priv;    int64_t pts;    int ret;     AVFrame *out = av_frame_clone(s->frames[s->current_frame]);     if (!out)        return AVERROR(ENOMEM);    out->pts += s->duration - s->start_pts;    pts = out->pts + out->pkt_duration;    ret = ff_filter_frame(outlink, out);    s->current_frame++;     if (s->current_frame >= s->nb_frames) {        s->duration = pts;        s->current_frame = 0;         if (s->loop > 0)            s->loop--;    }     return ret;} static int filter_frame(AVFilterLink *inlink, AVFrame *frame){    AVFilterContext *ctx = inlink->dst;    AVFilterLink *outlink = ctx->outputs[0];    LoopContext *s = ctx->priv;    int ret = 0;     if (inlink->frame_count_out >= s->start && s->size > 0 && s->loop != 0) {        if (s->nb_frames < s->size) {            if (!s->nb_frames)                s->start_pts = frame->pts;            s->frames[s->nb_frames] = av_frame_clone(frame);            if (!s->frames[s->nb_frames]) {                av_frame_free(&frame);                return AVERROR(ENOMEM);            }            s->nb_frames++;            s->duration = frame->pts + frame->pkt_duration;            ret = ff_filter_frame(outlink, frame);        } else {            av_frame_free(&frame);            ret = push_frame(ctx);        }    } else {        frame->pts += s->duration;        ret = ff_filter_frame(outlink, frame);    }     return ret;} static int request_frame(AVFilterLink *outlink){    AVFilterContext *ctx = outlink->src;    LoopContext *s = ctx->priv;    int ret = 0;     if ((!s->size) ||        (s->nb_frames < s->size) ||        (s->nb_frames >= s->size && s->loop == 0)) {        ret = ff_request_frame(ctx->inputs[0]);    } else {        ret = push_frame(ctx);    }     if (ret == AVERROR_EOF && s->nb_frames > 0 && s->loop != 0) {        ret = push_frame(ctx);    }     return ret;} static const AVOption loop_options[] = {    { "loop",  "number of loops",              OFFSET(loop),  AV_OPT_TYPE_INT,   {.i64 = 0 }, -1, INT_MAX,   VFLAGS },    { "size",  "max number of frames to loop", OFFSET(size),  AV_OPT_TYPE_INT64, {.i64 = 0 },  0, INT16_MAX, VFLAGS },    { "start", "set the loop start frame",     OFFSET(start), AV_OPT_TYPE_INT64, {.i64 = 0 },  0, INT64_MAX, VFLAGS },    { NULL }}; AVFILTER_DEFINE_CLASS(loop); static const AVFilterPad inputs[] = {    {        .name         = "default",        .type         = AVMEDIA_TYPE_VIDEO,        .filter_frame = filter_frame,    },    { NULL }}; static const AVFilterPad outputs[] = {    {        .name          = "default",        .type          = AVMEDIA_TYPE_VIDEO,        .request_frame = request_frame,    },    { NULL }}; AVFilter ff_vf_loop = {    .name        = "loop",    .description = NULL_IF_CONFIG_SMALL("Loop video frames."),    .priv_size   = sizeof(LoopContext),    .priv_class  = &loop_class,    .init        = init,    .uninit      = uninit,    .inputs      = inputs,    .outputs     = outputs,};#endif /* CONFIG_LOOP_FILTER */