mpv/audio/decode/ad_lavc.c

296 lines
8.1 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 General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU 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 "config.h"
#include "common/av_common.h"
#include "common/codecs.h"
#include "common/msg.h"
#include "options/options.h"
#include "ad.h"
#include "audio/fmt-conversion.h"
struct priv {
AVCodecContext *avctx;
AVFrame *avframe;
struct mp_audio frame;
bool force_channel_map;
uint32_t skip_samples, trim_samples;
bool preroll_done;
double next_pts;
AVRational codec_timebase;
};
static void uninit(struct dec_audio *da);
#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 int init(struct dec_audio *da, const char *decoder)
{
struct MPOpts *mpopts = da->opts;
struct ad_lavc_params *opts = mpopts->ad_lavc_params;
AVCodecContext *lavc_context;
AVCodec *lavc_codec;
struct mp_codec_params *c = da->codec;
struct priv *ctx = talloc_zero(NULL, struct priv);
da->priv = ctx;
ctx->codec_timebase = mp_get_codec_timebase(da->codec);
ctx->force_channel_map = c->force_channels;
lavc_codec = avcodec_find_decoder_by_name(decoder);
if (!lavc_codec) {
MP_ERR(da, "Cannot find codec '%s' in libavcodec...\n", decoder);
uninit(da);
return 0;
}
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, c) < 0) {
MP_ERR(da, "Could not set decoder parameters.\n");
uninit(da);
return 0;
}
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");
uninit(da);
return 0;
}
ctx->next_pts = MP_NOPTS_VALUE;
return 1;
}
static void uninit(struct dec_audio *da)
{
struct priv *ctx = da->priv;
if (!ctx)
return;
AVCodecContext *lavc_context = ctx->avctx;
if (lavc_context) {
if (avcodec_close(lavc_context) < 0)
MP_ERR(da, "Could not close codec.\n");
av_freep(&lavc_context->extradata);
av_freep(&lavc_context);
}
av_frame_free(&ctx->avframe);
}
static int control(struct dec_audio *da, int cmd, void *arg)
{
struct priv *ctx = da->priv;
switch (cmd) {
case ADCTRL_RESET:
avcodec_flush_buffers(ctx->avctx);
ctx->skip_samples = 0;
ctx->trim_samples = 0;
ctx->preroll_done = false;
ctx->next_pts = MP_NOPTS_VALUE;
return CONTROL_TRUE;
}
return CONTROL_UNKNOWN;
}
static bool send_packet(struct dec_audio *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 dec_audio *da, struct mp_audio **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.
control(da, ADCTRL_RESET, NULL);
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_audio *mpframe = mp_audio_from_avframe(priv->avframe);
if (!mpframe)
return true;
struct mp_chmap lavc_chmap = mpframe->channels;
if (lavc_chmap.num != avctx->channels)
mp_chmap_from_channels(&lavc_chmap, avctx->channels);
if (priv->force_channel_map) {
if (lavc_chmap.num == da->codec->channels.num)
lavc_chmap = da->codec->channels;
}
mp_audio_set_channels(mpframe, &lavc_chmap);
mpframe->pts = out_pts;
if (mpframe->pts == MP_NOPTS_VALUE)
mpframe->pts = priv->next_pts;
if (mpframe->pts != MP_NOPTS_VALUE)
priv->next_pts = mpframe->pts + mpframe->samples / (double)mpframe->rate;
#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, mpframe->samples);
if (skip) {
mp_audio_skip_samples(mpframe, skip);
priv->skip_samples -= skip;
}
uint32_t trim = MPMIN(priv->trim_samples, mpframe->samples);
if (trim) {
mpframe->samples -= trim;
priv->trim_samples -= trim;
}
*out = mpframe;
av_frame_unref(priv->avframe);
MP_DBG(da, "Decoded %d samples\n", mpframe->samples);
return true;
}
static void add_decoders(struct mp_decoder_list *list)
{
mp_add_lavc_decoders(list, AVMEDIA_TYPE_AUDIO);
}
const struct ad_functions ad_lavc = {
.name = "lavc",
.add_decoders = add_decoders,
.init = init,
.uninit = uninit,
.control = control,
.send_packet = send_packet,
.receive_frame = receive_frame,
};