mpv/audio/decode/ad_lavc.c

309 lines
8.5 KiB
C

/*
* This file is part of mpv.
*
* mpv 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.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdbool.h>
#include <assert.h>
#include <libavcodec/avcodec.h>
#include <libavutil/opt.h>
#include <libavutil/common.h>
#include <libavutil/intreadwrite.h>
#include "mpv_talloc.h"
#include "audio/aframe.h"
#include "audio/fmt-conversion.h"
#include "common/av_common.h"
#include "common/codecs.h"
#include "common/global.h"
#include "common/msg.h"
#include "demux/packet.h"
#include "demux/stheader.h"
#include "filters/f_decoder_wrapper.h"
#include "filters/filter_internal.h"
#include "options/options.h"
struct priv {
AVCodecContext *avctx;
AVFrame *avframe;
struct mp_chmap force_channel_map;
uint32_t skip_samples, trim_samples;
bool preroll_done;
double next_pts;
AVRational codec_timebase;
bool eof_returned;
struct mp_decoder public;
};
#define OPT_BASE_STRUCT struct ad_lavc_params
struct ad_lavc_params {
float ac3drc;
int downmix;
int threads;
char **avopts;
};
const struct m_sub_options ad_lavc_conf = {
.opts = (const m_option_t[]) {
OPT_FLOATRANGE("ac3drc", ac3drc, 0, 0, 6),
OPT_FLAG("downmix", downmix, 0),
OPT_INTRANGE("threads", threads, 0, 0, 16),
OPT_KEYVALUELIST("o", avopts, 0),
{0}
},
.size = sizeof(struct ad_lavc_params),
.defaults = &(const struct ad_lavc_params){
.ac3drc = 0,
.downmix = 1,
.threads = 1,
},
};
static bool init(struct mp_filter *da, struct mp_codec_params *codec,
const char *decoder)
{
struct priv *ctx = da->priv;
struct MPOpts *mpopts = da->global->opts;
struct ad_lavc_params *opts = mpopts->ad_lavc_params;
AVCodecContext *lavc_context;
AVCodec *lavc_codec;
ctx->codec_timebase = mp_get_codec_timebase(codec);
if (codec->force_channels)
ctx->force_channel_map = codec->channels;
lavc_codec = avcodec_find_decoder_by_name(decoder);
if (!lavc_codec) {
MP_ERR(da, "Cannot find codec '%s' in libavcodec...\n", decoder);
return false;
}
lavc_context = avcodec_alloc_context3(lavc_codec);
ctx->avctx = lavc_context;
ctx->avframe = av_frame_alloc();
lavc_context->codec_type = AVMEDIA_TYPE_AUDIO;
lavc_context->codec_id = lavc_codec->id;
#if LIBAVCODEC_VERSION_MICRO >= 100
lavc_context->pkt_timebase = ctx->codec_timebase;
#endif
if (opts->downmix && mpopts->audio_output_channels.num_chmaps == 1) {
lavc_context->request_channel_layout =
mp_chmap_to_lavc(&mpopts->audio_output_channels.chmaps[0]);
}
// Always try to set - option only exists for AC3 at the moment
av_opt_set_double(lavc_context, "drc_scale", opts->ac3drc,
AV_OPT_SEARCH_CHILDREN);
#if LIBAVCODEC_VERSION_MICRO >= 100
// Let decoder add AV_FRAME_DATA_SKIP_SAMPLES.
av_opt_set(lavc_context, "flags2", "+skip_manual", AV_OPT_SEARCH_CHILDREN);
#endif
mp_set_avopts(da->log, lavc_context, opts->avopts);
if (mp_set_avctx_codec_headers(lavc_context, codec) < 0) {
MP_ERR(da, "Could not set decoder parameters.\n");
return false;
}
mp_set_avcodec_threads(da->log, lavc_context, opts->threads);
/* open it */
if (avcodec_open2(lavc_context, lavc_codec, NULL) < 0) {
MP_ERR(da, "Could not open codec.\n");
return false;
}
ctx->next_pts = MP_NOPTS_VALUE;
return true;
}
static void destroy(struct mp_filter *da)
{
struct priv *ctx = da->priv;
avcodec_free_context(&ctx->avctx);
av_frame_free(&ctx->avframe);
}
static void reset(struct mp_filter *da)
{
struct priv *ctx = da->priv;
avcodec_flush_buffers(ctx->avctx);
ctx->skip_samples = 0;
ctx->trim_samples = 0;
ctx->preroll_done = false;
ctx->next_pts = MP_NOPTS_VALUE;
ctx->eof_returned = false;
}
static bool send_packet(struct mp_filter *da, struct demux_packet *mpkt)
{
struct priv *priv = da->priv;
AVCodecContext *avctx = priv->avctx;
// If the decoder discards the timestamp for some reason, we use the
// interpolated PTS. Initialize it so that it works for the initial
// packet as well.
if (mpkt && priv->next_pts == MP_NOPTS_VALUE)
priv->next_pts = mpkt->pts;
AVPacket pkt;
mp_set_av_packet(&pkt, mpkt, &priv->codec_timebase);
int ret = avcodec_send_packet(avctx, mpkt ? &pkt : NULL);
if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
return false;
if (ret < 0)
MP_ERR(da, "Error decoding audio.\n");
return true;
}
static bool receive_frame(struct mp_filter *da, struct mp_frame *out)
{
struct priv *priv = da->priv;
AVCodecContext *avctx = priv->avctx;
int ret = avcodec_receive_frame(avctx, priv->avframe);
if (ret == AVERROR_EOF) {
// If flushing was initialized earlier and has ended now, make it start
// over in case we get new packets at some point in the future.
// (Dont' reset the filter itself, we want to keep other state.)
avcodec_flush_buffers(priv->avctx);
return false;
} else if (ret < 0 && ret != AVERROR(EAGAIN)) {
MP_ERR(da, "Error decoding audio.\n");
}
#if LIBAVCODEC_VERSION_MICRO >= 100
if (priv->avframe->flags & AV_FRAME_FLAG_DISCARD)
av_frame_unref(priv->avframe);
#endif
if (!priv->avframe->buf[0])
return true;
double out_pts = mp_pts_from_av(priv->avframe->pts, &priv->codec_timebase);
struct mp_aframe *mpframe = mp_aframe_from_avframe(priv->avframe);
if (!mpframe)
return true;
if (priv->force_channel_map.num)
mp_aframe_set_chmap(mpframe, &priv->force_channel_map);
if (out_pts == MP_NOPTS_VALUE)
out_pts = priv->next_pts;
mp_aframe_set_pts(mpframe, out_pts);
priv->next_pts = mp_aframe_end_pts(mpframe);
#if LIBAVCODEC_VERSION_MICRO >= 100
AVFrameSideData *sd =
av_frame_get_side_data(priv->avframe, AV_FRAME_DATA_SKIP_SAMPLES);
if (sd && sd->size >= 10) {
char *d = sd->data;
priv->skip_samples += AV_RL32(d + 0);
priv->trim_samples += AV_RL32(d + 4);
}
#endif
if (!priv->preroll_done) {
// Skip only if this isn't already handled by AV_FRAME_DATA_SKIP_SAMPLES.
if (!priv->skip_samples)
priv->skip_samples = avctx->delay;
priv->preroll_done = true;
}
uint32_t skip = MPMIN(priv->skip_samples, mp_aframe_get_size(mpframe));
if (skip) {
mp_aframe_skip_samples(mpframe, skip);
priv->skip_samples -= skip;
}
uint32_t trim = MPMIN(priv->trim_samples, mp_aframe_get_size(mpframe));
if (trim) {
mp_aframe_set_size(mpframe, mp_aframe_get_size(mpframe) - trim);
priv->trim_samples -= trim;
}
*out = MAKE_FRAME(MP_FRAME_AUDIO, mpframe);
av_frame_unref(priv->avframe);
return true;
}
static void process(struct mp_filter *ad)
{
struct priv *priv = ad->priv;
lavc_process(ad, &priv->eof_returned, send_packet, receive_frame);
}
static const struct mp_filter_info ad_lavc_filter = {
.name = "ad_lavc",
.priv_size = sizeof(struct priv),
.process = process,
.reset = reset,
.destroy = destroy,
};
static struct mp_decoder *create(struct mp_filter *parent,
struct mp_codec_params *codec,
const char *decoder)
{
struct mp_filter *da = mp_filter_create(parent, &ad_lavc_filter);
if (!da)
return NULL;
mp_filter_add_pin(da, MP_PIN_IN, "in");
mp_filter_add_pin(da, MP_PIN_OUT, "out");
da->log = mp_log_new(da, parent->log, NULL);
struct priv *priv = da->priv;
priv->public.f = da;
if (!init(da, codec, decoder)) {
talloc_free(da);
return NULL;
}
return &priv->public;
}
static void add_decoders(struct mp_decoder_list *list)
{
mp_add_lavc_decoders(list, AVMEDIA_TYPE_AUDIO);
}
const struct mp_decoder_fns ad_lavc = {
.create = create,
.add_decoders = add_decoders,
};