/* * Copyright (c) 2020 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 "bsf.h" #include "bsf_internal.h" #include "libavutil/avassert.h" #include "libavutil/opt.h" typedef struct PCMContext { const AVClass *class; int nb_out_samples; int pad; AVRational frame_rate; AVPacket *in_pkt; AVPacket *out_pkt; int sample_size; int64_t n; } PCMContext; static int init(AVBSFContext *ctx) { PCMContext *s = ctx->priv_data; AVRational sr = av_make_q(ctx->par_in->sample_rate, 1); int64_t min_samples; if (ctx->par_in->ch_layout.nb_channels <= 0 || ctx->par_in->sample_rate <= 0) return AVERROR(EINVAL); ctx->time_base_out = av_inv_q(sr); s->sample_size = ctx->par_in->ch_layout.nb_channels * av_get_bits_per_sample(ctx->par_in->codec_id) / 8; if (s->frame_rate.num) { min_samples = av_rescale_q_rnd(1, sr, s->frame_rate, AV_ROUND_DOWN); } else { min_samples = s->nb_out_samples; } if (min_samples <= 0 || min_samples > INT_MAX / s->sample_size - 1) return AVERROR(EINVAL); s->in_pkt = av_packet_alloc(); s->out_pkt = av_packet_alloc(); if (!s->in_pkt || !s->out_pkt) return AVERROR(ENOMEM); return 0; } static void uninit(AVBSFContext *ctx) { PCMContext *s = ctx->priv_data; av_packet_free(&s->in_pkt); av_packet_free(&s->out_pkt); } static void flush(AVBSFContext *ctx) { PCMContext *s = ctx->priv_data; av_packet_unref(s->in_pkt); av_packet_unref(s->out_pkt); s->n = 0; } static int send_packet(PCMContext *s, int nb_samples, AVPacket *pkt) { pkt->duration = nb_samples; s->n++; return 0; } static void drain_packet(AVPacket *pkt, int drain_data, int drain_samples) { pkt->size -= drain_data; pkt->data += drain_data; if (pkt->dts != AV_NOPTS_VALUE) pkt->dts += drain_samples; if (pkt->pts != AV_NOPTS_VALUE) pkt->pts += drain_samples; } static int get_next_nb_samples(AVBSFContext *ctx) { PCMContext *s = ctx->priv_data; if (s->frame_rate.num) { AVRational sr = av_make_q(ctx->par_in->sample_rate, 1); return av_rescale_q(s->n + 1, sr, s->frame_rate) - av_rescale_q(s->n, sr, s->frame_rate); } else { return s->nb_out_samples; } } static int rechunk_filter(AVBSFContext *ctx, AVPacket *pkt) { PCMContext *s = ctx->priv_data; int nb_samples = get_next_nb_samples(ctx); int data_size = nb_samples * s->sample_size; int ret; do { if (s->in_pkt->size) { if (s->out_pkt->size || s->in_pkt->size < data_size) { int drain = FFMIN(s->in_pkt->size, data_size - s->out_pkt->size); if (!s->out_pkt->size) { ret = av_new_packet(s->out_pkt, data_size); if (ret < 0) return ret; ret = av_packet_copy_props(s->out_pkt, s->in_pkt); if (ret < 0) { av_packet_unref(s->out_pkt); return ret; } s->out_pkt->size = 0; } memcpy(s->out_pkt->data + s->out_pkt->size, s->in_pkt->data, drain); s->out_pkt->size += drain; drain_packet(s->in_pkt, drain, drain / s->sample_size); if (!s->in_pkt->size) av_packet_unref(s->in_pkt); if (s->out_pkt->size == data_size) { av_packet_move_ref(pkt, s->out_pkt); return send_packet(s, nb_samples, pkt); } } else if (s->in_pkt->size > data_size) { ret = av_packet_ref(pkt, s->in_pkt); if (ret < 0) return ret; pkt->size = data_size; drain_packet(s->in_pkt, data_size, nb_samples); return send_packet(s, nb_samples, pkt); } else { av_assert0(s->in_pkt->size == data_size); av_packet_move_ref(pkt, s->in_pkt); return send_packet(s, nb_samples, pkt); } } else av_packet_unref(s->in_pkt); ret = ff_bsf_get_packet_ref(ctx, s->in_pkt); if (ret == AVERROR_EOF && s->out_pkt->size) { if (s->pad) { memset(s->out_pkt->data + s->out_pkt->size, 0, data_size - s->out_pkt->size); s->out_pkt->size = data_size; } else { nb_samples = s->out_pkt->size / s->sample_size; } av_packet_move_ref(pkt, s->out_pkt); return send_packet(s, nb_samples, pkt); } if (ret >= 0) av_packet_rescale_ts(s->in_pkt, ctx->time_base_in, ctx->time_base_out); } while (ret >= 0); return ret; } #define OFFSET(x) offsetof(PCMContext, x) #define FLAGS (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_BSF_PARAM) static const AVOption options[] = { { "nb_out_samples", "set the number of per-packet output samples", OFFSET(nb_out_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, FLAGS }, { "n", "set the number of per-packet output samples", OFFSET(nb_out_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, FLAGS }, { "pad", "pad last packet with zeros", OFFSET(pad), AV_OPT_TYPE_BOOL, {.i64=1} , 0, 1, FLAGS }, { "p", "pad last packet with zeros", OFFSET(pad), AV_OPT_TYPE_BOOL, {.i64=1} , 0, 1, FLAGS }, { "frame_rate", "set number of packets per second", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS }, { "r", "set number of packets per second", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS }, { NULL }, }; static const AVClass pcm_rechunk_class = { .class_name = "pcm_rechunk_bsf", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; static const enum AVCodecID codec_ids[] = { AV_CODEC_ID_PCM_S16LE, AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S8, AV_CODEC_ID_PCM_S32LE, AV_CODEC_ID_PCM_S32BE, AV_CODEC_ID_PCM_S24LE, AV_CODEC_ID_PCM_S24BE, AV_CODEC_ID_PCM_F32BE, AV_CODEC_ID_PCM_F32LE, AV_CODEC_ID_PCM_F64BE, AV_CODEC_ID_PCM_F64LE, AV_CODEC_ID_PCM_S64LE, AV_CODEC_ID_PCM_S64BE, AV_CODEC_ID_PCM_F16LE, AV_CODEC_ID_PCM_F24LE, AV_CODEC_ID_NONE, }; const FFBitStreamFilter ff_pcm_rechunk_bsf = { .p.name = "pcm_rechunk", .p.codec_ids = codec_ids, .p.priv_class = &pcm_rechunk_class, .priv_data_size = sizeof(PCMContext), .filter = rechunk_filter, .init = init, .flush = flush, .close = uninit, };