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/*
* Interface to libmp3lame for mp3 encoding
* Copyright (c) 2002 Lennert Buytenhek <buytenh@gnu.org>
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/**
* @file mp3lameaudio.c
* Interface to libmp3lame for mp3 encoding.
*/
#include "avcodec.h"
#include "mpegaudio.h"
#include <lame/lame.h>
typedef struct Mp3AudioContext {
lame_global_flags *gfp;
int stereo;
} Mp3AudioContext;
static int MP3lame_encode_init(AVCodecContext *avctx)
{
Mp3AudioContext *s = avctx->priv_data;
if (avctx->channels > 2)
return -1;
s->stereo = avctx->channels > 1 ? 1 : 0;
if ((s->gfp = lame_init()) == NULL)
goto err;
lame_set_in_samplerate(s->gfp, avctx->sample_rate);
lame_set_out_samplerate(s->gfp, avctx->sample_rate);
lame_set_num_channels(s->gfp, avctx->channels);
/* lame 3.91 dies on quality != 5 */
lame_set_quality(s->gfp, 5);
/* lame 3.91 doesn't work in mono */
lame_set_mode(s->gfp, JOINT_STEREO);
lame_set_brate(s->gfp, avctx->bit_rate/1000);
if (lame_init_params(s->gfp) < 0)
goto err_close;
avctx->frame_size = MPA_FRAME_SIZE;
avctx->coded_frame= avcodec_alloc_frame();
avctx->coded_frame->key_frame= 1;
return 0;
err_close:
lame_close(s->gfp);
err:
return -1;
}
int MP3lame_encode_frame(AVCodecContext *avctx,
unsigned char *frame, int buf_size, void *data)
{
Mp3AudioContext *s = avctx->priv_data;
int num;
/* lame 3.91 dies on '1-channel interleaved' data */
if (s->stereo) {
num = lame_encode_buffer_interleaved(s->gfp, data,
MPA_FRAME_SIZE, frame, buf_size);
} else {
num = lame_encode_buffer(s->gfp, data, data, MPA_FRAME_SIZE,
frame, buf_size);
}
return num;
}
int MP3lame_encode_close(AVCodecContext *avctx)
{
Mp3AudioContext *s = avctx->priv_data;
av_freep(&avctx->coded_frame);
lame_close(s->gfp);
return 0;
}
AVCodec mp3lame_encoder = {
"mp3",
CODEC_TYPE_AUDIO,
CODEC_ID_MP3,
sizeof(Mp3AudioContext),
MP3lame_encode_init,
MP3lame_encode_frame,
MP3lame_encode_close
};
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