1 /* $Id: enclame.c,v 1.9 2005/03/05 14:27:05 titer Exp $
3 This file is part of the HandBrake source code.
4 Homepage: <http://handbrake.fr/>.
5 It may be used under the terms of the GNU General Public License. */
11 int enclameInit( hb_work_object_t *, hb_job_t * );
12 int enclameWork( hb_work_object_t *, hb_buffer_t **, hb_buffer_t ** );
13 void enclameClose( hb_work_object_t * );
15 hb_work_object_t hb_enclame =
18 "MP3 encoder (libmp3lame)",
24 struct hb_work_private_s
29 lame_global_flags * lame;
32 unsigned long input_samples;
33 unsigned long output_bytes;
40 int enclameInit( hb_work_object_t * w, hb_job_t * job )
42 hb_work_private_t * pv = calloc( 1, sizeof( hb_work_private_t ) );
43 hb_audio_t * audio = w->audio;
48 hb_log( "enclame: opening libmp3lame" );
50 pv->lame = lame_init();
52 lame_set_VBR( pv->lame, vbr_abr );
53 lame_set_VBR_mean_bitrate_kbps( pv->lame, audio->config.out.bitrate );
54 lame_set_in_samplerate( pv->lame, audio->config.out.samplerate );
55 lame_set_out_samplerate( pv->lame, audio->config.out.samplerate );
56 lame_init_params( pv->lame );
57 // Lame's default encoding mode is JOINT_STEREO. This subtracts signal
58 // that is "common" to left and right (within some threshold) and encodes
59 // it separately. This improves quality at low bitrates, but hurts
60 // imaging (channel separation) at higher bitrates. So if the bitrate
61 // is suffeciently high, use regular STEREO mode.
62 if ( audio->config.out.bitrate >= 128 )
63 lame_set_mode( pv->lame, STEREO );
65 pv->input_samples = 1152 * 2;
66 pv->output_bytes = LAME_MAXMP3BUFFER;
67 pv->buf = malloc( pv->input_samples * sizeof( float ) );
69 pv->list = hb_list_init();
75 /***********************************************************************
77 ***********************************************************************
79 **********************************************************************/
80 void enclameClose( hb_work_object_t * w )
82 hb_work_private_t * pv = w->private_data;
84 lame_close( pv->lame );
85 hb_list_empty( &pv->list );
88 w->private_data = NULL;
91 /***********************************************************************
93 ***********************************************************************
95 **********************************************************************/
96 static hb_buffer_t * Encode( hb_work_object_t * w )
98 hb_work_private_t * pv = w->private_data;
99 hb_audio_t * audio = w->audio;
101 int16_t samples_s16[1152 * 2];
105 if( hb_list_bytes( pv->list ) < pv->input_samples * sizeof( float ) )
110 hb_list_getbytes( pv->list, pv->buf, pv->input_samples * sizeof( float ),
113 for( i = 0; i < 1152 * 2; i++ )
115 samples_s16[i] = ((float*) pv->buf)[i];
118 buf = hb_buffer_init( pv->output_bytes );
119 buf->start = pts + 90000 * pos / 2 / sizeof( float ) / audio->config.out.samplerate;
120 buf->stop = buf->start + 90000 * 1152 / audio->config.out.samplerate;
121 buf->size = lame_encode_buffer_interleaved( pv->lame, samples_s16,
122 1152, buf->data, LAME_MAXMP3BUFFER );
123 buf->frametype = HB_FRAME_AUDIO;
127 /* Encoding was successful but we got no data. Try to encode
129 hb_buffer_close( &buf );
132 else if( buf->size < 0 )
134 hb_log( "enclame: lame_encode_buffer failed" );
135 hb_buffer_close( &buf );
142 /***********************************************************************
144 ***********************************************************************
146 **********************************************************************/
147 int enclameWork( hb_work_object_t * w, hb_buffer_t ** buf_in,
148 hb_buffer_t ** buf_out )
150 hb_work_private_t * pv = w->private_data;
151 hb_buffer_t * in = *buf_in;
154 if ( (*buf_in)->size <= 0 )
156 /* EOF on input - send it downstream & say we're done */
166 hb_fifo_push( w->fifo_in, in);
169 buf = hb_buffer_init( pv->output_bytes );
170 buf->size = lame_encode_flush( pv->lame, buf->data, LAME_MAXMP3BUFFER );
173 hb_buffer_close( &buf );
180 hb_list_add( pv->list, *buf_in );
183 *buf_out = buf = Encode( w );
187 buf->next = Encode( w );