ffmpeg/libavcodec/libshine.c

150 lines
4.9 KiB
C

/*
* Interface to libshine for mp3 encoding
* Copyright (c) 2012 Paul B Mahol
*
* 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 <shine/layer3.h>
#include "libavutil/intreadwrite.h"
#include "audio_frame_queue.h"
#include "avcodec.h"
#include "internal.h"
#include "mpegaudio.h"
#include "mpegaudiodecheader.h"
#define BUFFER_SIZE (4096 * 20)
typedef struct SHINEContext {
shine_config_t config;
shine_t shine;
uint8_t buffer[BUFFER_SIZE];
int buffer_index;
AudioFrameQueue afq;
} SHINEContext;
static av_cold int libshine_encode_init(AVCodecContext *avctx)
{
SHINEContext *s = avctx->priv_data;
if (avctx->channels <= 0 || avctx->channels > 2){
av_log(avctx, AV_LOG_ERROR, "only mono or stereo is supported\n");
return AVERROR(EINVAL);
}
shine_set_config_mpeg_defaults(&s->config.mpeg);
if (avctx->bit_rate)
s->config.mpeg.bitr = avctx->bit_rate / 1000;
if (shine_find_bitrate_index(s->config.mpeg.bitr) < 0) {
av_log(avctx, AV_LOG_ERROR, "invalid bitrate\n");
return AVERROR(EINVAL);
}
s->config.mpeg.mode = avctx->channels == 2 ? STEREO : MONO;
s->config.wave.samplerate = avctx->sample_rate;
s->config.wave.channels = avctx->channels == 2 ? PCM_STEREO : PCM_MONO;
s->shine = shine_initialise(&s->config);
if (!s->shine)
return AVERROR(ENOMEM);
avctx->frame_size = samp_per_frame;
ff_af_queue_init(avctx, &s->afq);
return 0;
}
static int libshine_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
const AVFrame *frame, int *got_packet_ptr)
{
SHINEContext *s = avctx->priv_data;
MPADecodeHeader hdr;
unsigned char *data;
long written;
int ret, len;
if (frame)
data = shine_encode_frame(s->shine, frame->data[0], &written);
else
data = shine_flush(s->shine, &written);
if (written < 0)
return -1;
if (written > 0) {
if (s->buffer_index + written > BUFFER_SIZE) {
av_log(avctx, AV_LOG_ERROR, "internal buffer too small\n");
return AVERROR_BUG;
}
memcpy(s->buffer + s->buffer_index, data, written);
s->buffer_index += written;
}
if (frame) {
if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
return ret;
}
if (s->buffer_index < 4 || !s->afq.frame_count)
return 0;
if (avpriv_mpegaudio_decode_header(&hdr, AV_RB32(s->buffer))) {
av_log(avctx, AV_LOG_ERROR, "free format output not supported\n");
return -1;
}
len = hdr.frame_size;
if (len <= s->buffer_index) {
if ((ret = ff_alloc_packet2(avctx, avpkt, len)))
return ret;
memcpy(avpkt->data, s->buffer, len);
s->buffer_index -= len;
memmove(s->buffer, s->buffer + len, s->buffer_index);
ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
&avpkt->duration);
avpkt->size = len;
*got_packet_ptr = 1;
}
return 0;
}
static av_cold int libshine_encode_close(AVCodecContext *avctx)
{
SHINEContext *s = avctx->priv_data;
ff_af_queue_close(&s->afq);
shine_close(s->shine);
return 0;
}
static const int libshine_sample_rates[] = {
44100, 48000, 32000, 0
};
AVCodec ff_libshine_encoder = {
.name = "libshine",
.type = AVMEDIA_TYPE_AUDIO,
.id = CODEC_ID_MP3,
.priv_data_size = sizeof(SHINEContext),
.init = libshine_encode_init,
.encode2 = libshine_encode_frame,
.close = libshine_encode_close,
.capabilities = CODEC_CAP_DELAY,
.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16P,
AV_SAMPLE_FMT_NONE },
.supported_samplerates = libshine_sample_rates,
.channel_layouts = (const uint64_t[]) { AV_CH_LAYOUT_MONO,
AV_CH_LAYOUT_STEREO,
0 },
.long_name = NULL_IF_CONFIG_SMALL("libshine MP3 (MPEG audio layer 3)"),
};