mirror of https://github.com/mpv-player/mpv
664 lines
23 KiB
C
664 lines
23 KiB
C
/*
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* audio encoding using libavformat
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* Copyright (C) 2011-2012 Rudolf Polzer <divVerent@xonotic.org>
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* NOTE: this file is partially based on ao_pcm.c by Atmosfear
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*
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* This file is part of mpv.
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*
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* MPlayer is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* MPlayer is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with MPlayer; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <libavutil/common.h>
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#include <libavutil/audioconvert.h>
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#include "compat/libav.h"
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#include "config.h"
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#include "core/options.h"
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#include "core/mp_common.h"
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#include "audio/format.h"
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#include "audio/reorder_ch.h"
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#include "talloc.h"
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#include "ao.h"
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#include "core/mp_msg.h"
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#include "core/encode_lavc.h"
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static const char *sample_padding_signed = "\x00\x00\x00\x00";
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static const char *sample_padding_u8 = "\x80";
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static const char *sample_padding_float = "\x00\x00\x00\x00";
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struct priv {
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uint8_t *buffer;
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size_t buffer_size;
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AVStream *stream;
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bool planarize;
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int pcmhack;
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int aframesize;
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int aframecount;
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int offset;
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int offset_left;
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int64_t savepts;
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int framecount;
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int64_t lastpts;
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int sample_size;
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const void *sample_padding;
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double expected_next_pts;
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AVRational worst_time_base;
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int worst_time_base_is_stream;
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};
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// open & setup audio device
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static int init(struct ao *ao, char *params)
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{
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struct priv *ac = talloc_zero(ao, struct priv);
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const enum AVSampleFormat *sampleformat;
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AVCodec *codec;
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if (!encode_lavc_available(ao->encode_lavc_ctx)) {
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mp_msg(MSGT_ENCODE, MSGL_ERR,
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"ao-lavc: the option -o (output file) must be specified\n");
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return -1;
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}
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if (ac->stream) {
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mp_msg(MSGT_ENCODE, MSGL_ERR, "ao-lavc: rejecting reinitialization\n");
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return -1;
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}
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ac->stream = encode_lavc_alloc_stream(ao->encode_lavc_ctx,
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AVMEDIA_TYPE_AUDIO);
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if (!ac->stream) {
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mp_msg(MSGT_ENCODE, MSGL_ERR, "ao-lavc: could not get a new audio stream\n");
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return -1;
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}
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codec = encode_lavc_get_codec(ao->encode_lavc_ctx, ac->stream);
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// ac->stream->time_base.num = 1;
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// ac->stream->time_base.den = ao->samplerate;
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// doing this breaks mpeg2ts in ffmpeg
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// which doesn't properly force the time base to be 90000
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// furthermore, ffmpeg.c doesn't do this either and works
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ac->stream->codec->time_base.num = 1;
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ac->stream->codec->time_base.den = ao->samplerate;
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ac->stream->codec->sample_rate = ao->samplerate;
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struct mp_chmap_sel sel = {0};
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mp_chmap_sel_add_any(&sel);
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if (!ao_chmap_sel_adjust(ao, &sel, &ao->channels))
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return -1;
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mp_chmap_reorder_to_lavc(&ao->channels);
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ac->stream->codec->channels = ao->channels.num;
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ac->stream->codec->channel_layout = mp_chmap_to_lavc(&ao->channels);
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ac->stream->codec->sample_fmt = AV_SAMPLE_FMT_NONE;
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{
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// first check if the selected format is somewhere in the list of
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// supported formats by the codec
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for (sampleformat = codec->sample_fmts;
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sampleformat && *sampleformat != AV_SAMPLE_FMT_NONE;
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++sampleformat) {
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switch (*sampleformat) {
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case AV_SAMPLE_FMT_U8:
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case AV_SAMPLE_FMT_U8P:
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if (ao->format == AF_FORMAT_U8)
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goto out_search;
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break;
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case AV_SAMPLE_FMT_S16:
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case AV_SAMPLE_FMT_S16P:
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if (ao->format == AF_FORMAT_S16_BE)
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goto out_search;
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if (ao->format == AF_FORMAT_S16_LE)
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goto out_search;
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break;
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case AV_SAMPLE_FMT_S32:
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case AV_SAMPLE_FMT_S32P:
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if (ao->format == AF_FORMAT_S32_BE)
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goto out_search;
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if (ao->format == AF_FORMAT_S32_LE)
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goto out_search;
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break;
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case AV_SAMPLE_FMT_FLT:
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case AV_SAMPLE_FMT_FLTP:
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if (ao->format == AF_FORMAT_FLOAT_BE)
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goto out_search;
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if (ao->format == AF_FORMAT_FLOAT_LE)
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goto out_search;
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break;
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// FIXME do we need support for AV_SAMPLE_FORMAT_DBL/DBLP?
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default:
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break;
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}
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}
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out_search:
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;
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}
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if (!sampleformat || *sampleformat == AV_SAMPLE_FMT_NONE) {
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// if the selected format is not supported, we have to pick the first
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// one we CAN support
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// note: not needing to select endianness here, as the switch() below
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// does that anyway for us
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for (sampleformat = codec->sample_fmts;
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sampleformat && *sampleformat != AV_SAMPLE_FMT_NONE;
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++sampleformat) {
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switch (*sampleformat) {
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case AV_SAMPLE_FMT_U8:
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case AV_SAMPLE_FMT_U8P:
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ao->format = AF_FORMAT_U8;
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goto out_takefirst;
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case AV_SAMPLE_FMT_S16:
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case AV_SAMPLE_FMT_S16P:
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ao->format = AF_FORMAT_S16_NE;
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goto out_takefirst;
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case AV_SAMPLE_FMT_S32:
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case AV_SAMPLE_FMT_S32P:
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ao->format = AF_FORMAT_S32_NE;
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goto out_takefirst;
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case AV_SAMPLE_FMT_FLT:
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case AV_SAMPLE_FMT_FLTP:
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ao->format = AF_FORMAT_FLOAT_NE;
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goto out_takefirst;
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// FIXME do we need support for AV_SAMPLE_FORMAT_DBL/DBLP?
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default:
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break;
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}
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}
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out_takefirst:
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;
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}
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switch (ao->format) {
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// now that we have chosen a format, set up the fields for it, boldly
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// switching endianness if needed (mplayer code will convert for us
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// anyway, but ffmpeg always expects native endianness)
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case AF_FORMAT_U8:
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ac->stream->codec->sample_fmt = AV_SAMPLE_FMT_U8;
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ac->sample_size = 1;
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ac->sample_padding = sample_padding_u8;
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ao->format = AF_FORMAT_U8;
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break;
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default:
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case AF_FORMAT_S16_BE:
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case AF_FORMAT_S16_LE:
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ac->stream->codec->sample_fmt = AV_SAMPLE_FMT_S16;
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ac->sample_size = 2;
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ac->sample_padding = sample_padding_signed;
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ao->format = AF_FORMAT_S16_NE;
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break;
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case AF_FORMAT_S32_BE:
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case AF_FORMAT_S32_LE:
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ac->stream->codec->sample_fmt = AV_SAMPLE_FMT_S32;
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ac->sample_size = 4;
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ac->sample_padding = sample_padding_signed;
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ao->format = AF_FORMAT_S32_NE;
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break;
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case AF_FORMAT_FLOAT_BE:
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case AF_FORMAT_FLOAT_LE:
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ac->stream->codec->sample_fmt = AV_SAMPLE_FMT_FLT;
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ac->sample_size = 4;
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ac->sample_padding = sample_padding_float;
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ao->format = AF_FORMAT_FLOAT_NE;
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break;
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}
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// detect if we have to planarize
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ac->planarize = false;
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{
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bool found_format = false;
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bool found_planar_format = false;
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for (sampleformat = codec->sample_fmts;
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sampleformat && *sampleformat != AV_SAMPLE_FMT_NONE;
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++sampleformat) {
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if (*sampleformat == ac->stream->codec->sample_fmt)
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found_format = true;
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if (*sampleformat ==
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av_get_planar_sample_fmt(ac->stream->codec->sample_fmt))
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found_planar_format = true;
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}
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if (!found_format && found_planar_format) {
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ac->stream->codec->sample_fmt =
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av_get_planar_sample_fmt(ac->stream->codec->sample_fmt);
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ac->planarize = true;
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}
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if (!found_format && !found_planar_format) {
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// shouldn't happen
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mp_msg(MSGT_ENCODE, MSGL_ERR,
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"ao-lavc: sample format not found\n");
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}
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}
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ac->stream->codec->bits_per_raw_sample = ac->sample_size * 8;
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if (encode_lavc_open_codec(ao->encode_lavc_ctx, ac->stream) < 0)
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return -1;
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ac->pcmhack = 0;
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if (ac->stream->codec->frame_size <= 1)
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ac->pcmhack = av_get_bits_per_sample(ac->stream->codec->codec_id) / 8;
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if (ac->pcmhack) {
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ac->aframesize = 16384; // "enough"
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ac->buffer_size =
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ac->aframesize * ac->pcmhack * ao->channels.num * 2 + 200;
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} else {
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ac->aframesize = ac->stream->codec->frame_size;
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ac->buffer_size =
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ac->aframesize * ac->sample_size * ao->channels.num * 2 + 200;
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}
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if (ac->buffer_size < FF_MIN_BUFFER_SIZE)
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ac->buffer_size = FF_MIN_BUFFER_SIZE;
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ac->buffer = talloc_size(ac, ac->buffer_size);
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// enough frames for at least 0.25 seconds
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ac->framecount = ceil(ao->samplerate * 0.25 / ac->aframesize);
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// but at least one!
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ac->framecount = FFMAX(ac->framecount, 1);
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ac->savepts = MP_NOPTS_VALUE;
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ac->lastpts = MP_NOPTS_VALUE;
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ac->offset = ac->stream->codec->sample_rate *
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encode_lavc_getoffset(ao->encode_lavc_ctx, ac->stream);
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ac->offset_left = ac->offset;
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//fill_ao_data:
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ao->outburst =
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ac->aframesize * ac->sample_size * ao->channels.num * ac->framecount;
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ao->buffersize = ao->outburst * 2;
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ao->bps = ao->channels.num * ao->samplerate * ac->sample_size;
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ao->untimed = true;
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ao->priv = ac;
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if (ac->planarize)
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mp_msg(MSGT_ENCODE, MSGL_WARN,
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"ao-lavc: need to planarize audio data\n");
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return 0;
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}
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static void fill_with_padding(void *buf, int cnt, int sz, const void *padding)
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{
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int i;
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if (sz == 1) {
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memset(buf, cnt, *(char *)padding);
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return;
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}
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for (i = 0; i < cnt; ++i)
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memcpy((char *) buf + i * sz, padding, sz);
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}
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// close audio device
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static int encode(struct ao *ao, double apts, void *data);
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static int play(struct ao *ao, void *data, int len, int flags);
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static void uninit(struct ao *ao, bool cut_audio)
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{
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struct priv *ac = ao->priv;
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struct encode_lavc_context *ectx = ao->encode_lavc_ctx;
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if (!encode_lavc_start(ectx)) {
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mp_msg(MSGT_ENCODE, MSGL_WARN,
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"ao-lavc: not even ready to encode audio at end -> dropped");
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return;
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}
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if (ac->buffer) {
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if (ao->buffer.len > 0) {
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// TRICK: append aframesize-1 samples to the end, then play() will
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// encode all it can
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size_t extralen =
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(ac->aframesize - 1) * ao->channels.num * ac->sample_size;
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void *paddingbuf = talloc_size(ao, ao->buffer.len + extralen);
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memcpy(paddingbuf, ao->buffer.start, ao->buffer.len);
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fill_with_padding((char *) paddingbuf + ao->buffer.len,
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extralen / ac->sample_size,
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ac->sample_size, ac->sample_padding);
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int written = play(ao, paddingbuf, ao->buffer.len + extralen, 0);
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if (written < ao->buffer.len) {
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mp_msg(MSGT_ENCODE, MSGL_ERR,
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"ao-lavc: did not write enough data at the end\n");
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}
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talloc_free(paddingbuf);
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ao->buffer.len = 0;
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}
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double outpts = ac->expected_next_pts;
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if (!ectx->options->rawts && ectx->options->copyts)
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outpts += ectx->discontinuity_pts_offset;
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outpts += encode_lavc_getoffset(ectx, ac->stream);
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while (encode(ao, outpts, NULL) > 0) ;
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}
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ao->priv = NULL;
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}
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// return: how many bytes can be played without blocking
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static int get_space(struct ao *ao)
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{
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return ao->outburst;
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}
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// must get exactly ac->aframesize amount of data
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static int encode(struct ao *ao, double apts, void *data)
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{
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AVFrame *frame;
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AVPacket packet;
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struct priv *ac = ao->priv;
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struct encode_lavc_context *ectx = ao->encode_lavc_ctx;
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double realapts = ac->aframecount * (double) ac->aframesize /
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ao->samplerate;
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int status, gotpacket;
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ac->aframecount++;
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if (data)
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ectx->audio_pts_offset = realapts - apts;
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av_init_packet(&packet);
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packet.data = ac->buffer;
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packet.size = ac->buffer_size;
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if(data)
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{
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frame = avcodec_alloc_frame();
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frame->nb_samples = ac->aframesize;
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if (ac->planarize) {
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void *data2 = talloc_size(ao, ac->aframesize * ao->channels.num *
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ac->sample_size);
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reorder_to_planar(data2, data, ac->sample_size, ao->channels.num,
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ac->aframesize);
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data = data2;
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}
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size_t audiolen = ac->aframesize * ao->channels.num * ac->sample_size;
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if (avcodec_fill_audio_frame(frame, ao->channels.num,
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ac->stream->codec->sample_fmt, data,
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audiolen, 1))
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{
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mp_msg(MSGT_ENCODE, MSGL_ERR, "ao-lavc: error filling\n");
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return -1;
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}
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if (ectx->options->rawts || ectx->options->copyts) {
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// real audio pts
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frame->pts = floor(apts * ac->stream->codec->time_base.den / ac->stream->codec->time_base.num + 0.5);
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} else {
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// audio playback time
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frame->pts = floor(realapts * ac->stream->codec->time_base.den / ac->stream->codec->time_base.num + 0.5);
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}
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int64_t frame_pts = av_rescale_q(frame->pts, ac->stream->codec->time_base, ac->worst_time_base);
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if (ac->lastpts != MP_NOPTS_VALUE && frame_pts <= ac->lastpts) {
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// this indicates broken video
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// (video pts failing to increase fast enough to match audio)
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mp_msg(MSGT_ENCODE, MSGL_WARN, "ao-lavc: audio frame pts went backwards "
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"(%d <- %d), autofixed\n", (int)frame->pts,
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(int)ac->lastpts);
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frame_pts = ac->lastpts + 1;
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frame->pts = av_rescale_q(frame_pts, ac->worst_time_base, ac->stream->codec->time_base);
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}
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ac->lastpts = frame_pts;
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frame->quality = ac->stream->codec->global_quality;
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status = avcodec_encode_audio2(ac->stream->codec, &packet, frame, &gotpacket);
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if (!status) {
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if (ac->savepts == MP_NOPTS_VALUE)
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ac->savepts = frame->pts;
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}
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avcodec_free_frame(&frame);
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if (ac->planarize) {
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talloc_free(data);
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data = NULL;
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}
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}
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else
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{
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status = avcodec_encode_audio2(ac->stream->codec, &packet, NULL, &gotpacket);
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}
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if(status)
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{
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mp_msg(MSGT_ENCODE, MSGL_ERR, "ao-lavc: error encoding\n");
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return -1;
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}
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if(!gotpacket)
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return 0;
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mp_msg(MSGT_ENCODE, MSGL_DBG2,
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"ao-lavc: got pts %f (playback time: %f); out size: %d\n",
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apts, realapts, packet.size);
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encode_lavc_write_stats(ao->encode_lavc_ctx, ac->stream);
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packet.stream_index = ac->stream->index;
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// Do we need this at all? Better be safe than sorry...
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if (packet.pts == AV_NOPTS_VALUE) {
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mp_msg(MSGT_ENCODE, MSGL_WARN, "ao-lavc: encoder lost pts, why?\n");
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if (ac->savepts != MP_NOPTS_VALUE)
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packet.pts = ac->savepts;
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}
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if (packet.pts != AV_NOPTS_VALUE)
|
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packet.pts = av_rescale_q(packet.pts, ac->stream->codec->time_base,
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ac->stream->time_base);
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if (packet.dts != AV_NOPTS_VALUE)
|
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packet.dts = av_rescale_q(packet.dts, ac->stream->codec->time_base,
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ac->stream->time_base);
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|
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if(packet.duration > 0)
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packet.duration = av_rescale_q(packet.duration, ac->stream->codec->time_base,
|
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ac->stream->time_base);
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|
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ac->savepts = MP_NOPTS_VALUE;
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|
|
if (encode_lavc_write_frame(ao->encode_lavc_ctx, &packet) < 0) {
|
|
mp_msg(MSGT_ENCODE, MSGL_ERR, "ao-lavc: error writing at %f %f/%f\n",
|
|
realapts, (double) ac->stream->time_base.num,
|
|
(double) ac->stream->time_base.den);
|
|
return -1;
|
|
}
|
|
|
|
return packet.size;
|
|
}
|
|
|
|
// plays 'len' bytes of 'data'
|
|
// it should round it down to outburst*n
|
|
// return: number of bytes played
|
|
static int play(struct ao *ao, void *data, int len, int flags)
|
|
{
|
|
struct priv *ac = ao->priv;
|
|
struct encode_lavc_context *ectx = ao->encode_lavc_ctx;
|
|
int bufpos = 0;
|
|
int64_t ptsoffset;
|
|
void *paddingbuf = NULL;
|
|
double nextpts;
|
|
double pts = ao->pts;
|
|
double outpts;
|
|
|
|
len /= ac->sample_size * ao->channels.num;
|
|
|
|
if (!encode_lavc_start(ectx)) {
|
|
mp_msg(MSGT_ENCODE, MSGL_WARN,
|
|
"ao-lavc: not ready yet for encoding audio\n");
|
|
return 0;
|
|
}
|
|
if (pts == MP_NOPTS_VALUE) {
|
|
mp_msg(MSGT_ENCODE, MSGL_WARN,
|
|
"ao-lavc: frame without pts, please report; synthesizing pts instead\n");
|
|
// synthesize pts from previous expected next pts
|
|
pts = ac->expected_next_pts;
|
|
}
|
|
|
|
if (ac->worst_time_base.den == 0) {
|
|
//if (ac->stream->codec->time_base.num / ac->stream->codec->time_base.den >= ac->stream->time_base.num / ac->stream->time_base.den)
|
|
if (ac->stream->codec->time_base.num * (double) ac->stream->time_base.den >=
|
|
ac->stream->time_base.num * (double) ac->stream->codec->time_base.den) {
|
|
mp_msg(MSGT_ENCODE, MSGL_V, "ao-lavc: NOTE: using codec time base "
|
|
"(%d/%d) for pts adjustment; the stream base (%d/%d) is "
|
|
"not worse.\n", (int)ac->stream->codec->time_base.num,
|
|
(int)ac->stream->codec->time_base.den, (int)ac->stream->time_base.num,
|
|
(int)ac->stream->time_base.den);
|
|
ac->worst_time_base = ac->stream->codec->time_base;
|
|
ac->worst_time_base_is_stream = 0;
|
|
} else {
|
|
mp_msg(MSGT_ENCODE, MSGL_WARN, "ao-lavc: NOTE: not using codec time "
|
|
"base (%d/%d) for pts adjustment; the stream base (%d/%d) "
|
|
"is worse.\n", (int)ac->stream->codec->time_base.num,
|
|
(int)ac->stream->codec->time_base.den, (int)ac->stream->time_base.num,
|
|
(int)ac->stream->time_base.den);
|
|
ac->worst_time_base = ac->stream->time_base;
|
|
ac->worst_time_base_is_stream = 1;
|
|
}
|
|
|
|
// NOTE: we use the following "axiom" of av_rescale_q:
|
|
// if time base A is worse than time base B, then
|
|
// av_rescale_q(av_rescale_q(x, A, B), B, A) == x
|
|
// this can be proven as long as av_rescale_q rounds to nearest, which
|
|
// it currently does
|
|
|
|
// av_rescale_q(x, A, B) * B = "round x*A to nearest multiple of B"
|
|
// and:
|
|
// av_rescale_q(av_rescale_q(x, A, B), B, A) * A
|
|
// == "round av_rescale_q(x, A, B)*B to nearest multiple of A"
|
|
// == "round 'round x*A to nearest multiple of B' to nearest multiple of A"
|
|
//
|
|
// assume this fails. Then there is a value of x*A, for which the
|
|
// nearest multiple of B is outside the range [(x-0.5)*A, (x+0.5)*A[.
|
|
// Absurd, as this range MUST contain at least one multiple of B.
|
|
}
|
|
|
|
ptsoffset = ac->offset;
|
|
// this basically just edits ao->apts for syncing purposes
|
|
|
|
if (ectx->options->copyts || ectx->options->rawts) {
|
|
// we do not send time sync data to the video side,
|
|
// but we always need the exact pts, even if zero
|
|
} else {
|
|
// here we must "simulate" the pts editing
|
|
// 1. if we have to skip stuff, we skip it
|
|
// 2. if we have to add samples, we add them
|
|
// 3. we must still adjust ptsoffset appropriately for AV sync!
|
|
// invariant:
|
|
// if no partial skipping is done, the first frame gets ao->apts passed as pts!
|
|
|
|
if (ac->offset_left < 0) {
|
|
if (ac->offset_left <= -len) {
|
|
// skip whole frame
|
|
ac->offset_left += len;
|
|
return len * ac->sample_size * ao->channels.num;
|
|
} else {
|
|
// skip part of this frame, buffer/encode the rest
|
|
bufpos -= ac->offset_left;
|
|
ptsoffset += ac->offset_left;
|
|
ac->offset_left = 0;
|
|
}
|
|
} else if (ac->offset_left > 0) {
|
|
// make a temporary buffer, filled with zeroes at the start
|
|
// (don't worry, only happens once)
|
|
|
|
paddingbuf = talloc_size(ac, ac->sample_size * ao->channels.num *
|
|
(ac->offset_left + len));
|
|
fill_with_padding(paddingbuf, ac->offset_left, ac->sample_size,
|
|
ac->sample_padding);
|
|
data = (char *) paddingbuf + ac->sample_size * ao->channels.num *
|
|
ac->offset_left;
|
|
bufpos -= ac->offset_left; // yes, negative!
|
|
ptsoffset += ac->offset_left;
|
|
ac->offset_left = 0;
|
|
|
|
// now adjust the bufpos so the final value of bufpos is positive!
|
|
/*
|
|
int cnt = (len - bufpos) / ac->aframesize;
|
|
int finalbufpos = bufpos + cnt * ac->aframesize;
|
|
*/
|
|
int finalbufpos = len - (len - bufpos) % ac->aframesize;
|
|
if (finalbufpos < 0) {
|
|
mp_msg(MSGT_ENCODE, MSGL_WARN, "ao-lavc: cannot attain the "
|
|
"exact requested audio sync; shifting by %d frames\n",
|
|
-finalbufpos);
|
|
bufpos -= finalbufpos;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!ectx->options->rawts && ectx->options->copyts) {
|
|
// fix the discontinuity pts offset
|
|
nextpts = pts + ptsoffset / (double) ao->samplerate;
|
|
if (ectx->discontinuity_pts_offset == MP_NOPTS_VALUE) {
|
|
ectx->discontinuity_pts_offset = ectx->next_in_pts - nextpts;
|
|
}
|
|
else if (fabs(nextpts + ectx->discontinuity_pts_offset - ectx->next_in_pts) > 30) {
|
|
mp_msg(MSGT_ENCODE, MSGL_WARN,
|
|
"ao-lavc: detected an unexpected discontinuity (pts jumped by "
|
|
"%f seconds)\n",
|
|
nextpts + ectx->discontinuity_pts_offset - ectx->next_in_pts);
|
|
ectx->discontinuity_pts_offset = ectx->next_in_pts - nextpts;
|
|
}
|
|
|
|
outpts = pts + ectx->discontinuity_pts_offset;
|
|
}
|
|
else
|
|
outpts = pts;
|
|
|
|
while (len - bufpos >= ac->aframesize) {
|
|
encode(ao,
|
|
outpts + (bufpos + ptsoffset) / (double) ao->samplerate + encode_lavc_getoffset(ectx, ac->stream),
|
|
(char *) data + ac->sample_size * bufpos * ao->channels.num);
|
|
bufpos += ac->aframesize;
|
|
}
|
|
|
|
talloc_free(paddingbuf);
|
|
|
|
// calculate expected pts of next audio frame
|
|
ac->expected_next_pts = pts + (bufpos + ptsoffset) / (double) ao->samplerate;
|
|
|
|
if (!ectx->options->rawts && ectx->options->copyts) {
|
|
// set next allowed output pts value
|
|
nextpts = ac->expected_next_pts + ectx->discontinuity_pts_offset;
|
|
if (nextpts > ectx->next_in_pts)
|
|
ectx->next_in_pts = nextpts;
|
|
}
|
|
|
|
return bufpos * ac->sample_size * ao->channels.num;
|
|
}
|
|
|
|
const struct ao_driver audio_out_lavc = {
|
|
.encode = true,
|
|
.info = &(const struct ao_info) {
|
|
"audio encoding using libavcodec",
|
|
"lavc",
|
|
"Rudolf Polzer <divVerent@xonotic.org>",
|
|
""
|
|
},
|
|
.init = init,
|
|
.uninit = uninit,
|
|
.get_space = get_space,
|
|
.play = play,
|
|
};
|