/* * Generic frame queue * Copyright (c) 2016 Nicolas George * * 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/avassert.h"#include "framequeue.h" static inline FFFrameBucket *bucket(FFFrameQueue *fq, size_t idx){    return &fq->queue[(fq->tail + idx) & (fq->allocated - 1)];} void ff_framequeue_global_init(FFFrameQueueGlobal *fqg){} static void check_consistency(FFFrameQueue *fq){#if defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2    uint64_t nb_samples = 0;    size_t i;     av_assert0(fq->queued == fq->total_frames_head - fq->total_frames_tail);    for (i = 0; i < fq->queued; i++)        nb_samples += bucket(fq, i)->frame->nb_samples;    av_assert0(nb_samples == fq->total_samples_head - fq->total_samples_tail);#endif} void ff_framequeue_init(FFFrameQueue *fq, FFFrameQueueGlobal *fqg){    fq->queue = &fq->first_bucket;    fq->allocated = 1;} void ff_framequeue_free(FFFrameQueue *fq){    while (fq->queued) {        AVFrame *frame = ff_framequeue_take(fq);        av_frame_free(&frame);    }    if (fq->queue != &fq->first_bucket)        av_freep(&fq->queue);} int ff_framequeue_add(FFFrameQueue *fq, AVFrame *frame){    FFFrameBucket *b;     check_consistency(fq);    if (fq->queued == fq->allocated) {        if (fq->allocated == 1) {            size_t na = 8;            FFFrameBucket *nq = av_realloc_array(NULL, na, sizeof(*nq));            if (!nq)                return AVERROR(ENOMEM);            nq[0] = fq->queue[0];            fq->queue = nq;            fq->allocated = na;        } else {            size_t na = fq->allocated << 1;            FFFrameBucket *nq = av_realloc_array(fq->queue, na, sizeof(*nq));            if (!nq)                return AVERROR(ENOMEM);            if (fq->tail + fq->queued > fq->allocated)                memmove(nq + fq->allocated, nq,                        (fq->tail + fq->queued - fq->allocated) * sizeof(*nq));            fq->queue = nq;            fq->allocated = na;        }    }    b = bucket(fq, fq->queued);    b->frame = frame;    fq->queued++;    fq->total_frames_head++;    fq->total_samples_head += frame->nb_samples;    check_consistency(fq);    return 0;} AVFrame *ff_framequeue_take(FFFrameQueue *fq){    FFFrameBucket *b;     check_consistency(fq);    av_assert1(fq->queued);    b = bucket(fq, 0);    fq->queued--;    fq->tail++;    fq->tail &= fq->allocated - 1;    fq->total_frames_tail++;    fq->total_samples_tail += b->frame->nb_samples;    fq->samples_skipped = 0;    check_consistency(fq);    return b->frame;} AVFrame *ff_framequeue_peek(FFFrameQueue *fq, size_t idx){    FFFrameBucket *b;     check_consistency(fq);    av_assert1(idx < fq->queued);    b = bucket(fq, idx);    check_consistency(fq);    return b->frame;} void ff_framequeue_skip_samples(FFFrameQueue *fq, size_t samples, AVRational time_base){    FFFrameBucket *b;    size_t bytes;    int planar, planes, i;     check_consistency(fq);    av_assert1(fq->queued);    b = bucket(fq, 0);    av_assert1(samples < b->frame->nb_samples);    planar = av_sample_fmt_is_planar(b->frame->format);    planes = planar ? b->frame->channels : 1;    bytes = samples * av_get_bytes_per_sample(b->frame->format);    if (!planar)        bytes *= b->frame->channels;    if (b->frame->pts != AV_NOPTS_VALUE)        b->frame->pts += av_rescale_q(samples, av_make_q(1, b->frame->sample_rate), time_base);    b->frame->nb_samples -= samples;    b->frame->linesize[0] -= bytes;    for (i = 0; i < planes; i++)        b->frame->extended_data[i] += bytes;    for (i = 0; i < planes && i < AV_NUM_DATA_POINTERS; i++)        b->frame->data[i] = b->frame->extended_data[i];    fq->total_samples_tail += samples;    fq->samples_skipped = 1;    ff_framequeue_update_peeked(fq, 0);}