2 * Interface to libmp3lame for mp3 encoding
3 * Copyright (c) 2002 Lennert Buytenhek <buytenh@gnu.org>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 * @file mp3lameaudio.c
22 * Interface to libmp3lame for mp3 encoding.
26 #include "mpegaudio.h"
27 #include <lame/lame.h>
29 typedef struct Mp3AudioContext {
30 lame_global_flags *gfp;
35 static int MP3lame_encode_init(AVCodecContext *avctx)
37 Mp3AudioContext *s = avctx->priv_data;
39 if (avctx->channels > 2)
42 s->stereo = avctx->channels > 1 ? 1 : 0;
44 if ((s->gfp = lame_init()) == NULL)
46 lame_set_in_samplerate(s->gfp, avctx->sample_rate);
47 lame_set_out_samplerate(s->gfp, avctx->sample_rate);
48 lame_set_num_channels(s->gfp, avctx->channels);
49 /* lame 3.91 dies on quality != 5 */
50 lame_set_quality(s->gfp, 5);
51 /* lame 3.91 doesn't work in mono */
52 lame_set_mode(s->gfp, JOINT_STEREO);
53 lame_set_brate(s->gfp, avctx->bit_rate/1000);
54 if (lame_init_params(s->gfp) < 0)
57 avctx->frame_size = MPA_FRAME_SIZE;
59 avctx->coded_frame= avcodec_alloc_frame();
60 avctx->coded_frame->key_frame= 1;
70 int MP3lame_encode_frame(AVCodecContext *avctx,
71 unsigned char *frame, int buf_size, void *data)
73 Mp3AudioContext *s = avctx->priv_data;
76 /* lame 3.91 dies on '1-channel interleaved' data */
78 num = lame_encode_buffer_interleaved(s->gfp, data,
79 MPA_FRAME_SIZE, frame, buf_size);
81 num = lame_encode_buffer(s->gfp, data, data, MPA_FRAME_SIZE,
88 int MP3lame_encode_close(AVCodecContext *avctx)
90 Mp3AudioContext *s = avctx->priv_data;
92 av_freep(&avctx->coded_frame);
99 AVCodec mp3lame_encoder = {
103 sizeof(Mp3AudioContext),
105 MP3lame_encode_frame,