1 /* $Id: deca52.c,v 1.14 2005/03/03 17:21:57 titer Exp $
3 This file is part of the HandBrake source code.
4 Homepage: <http://handbrake.m0k.org/>.
5 It may be used under the terms of the GNU General Public License. */
9 #include "a52dec/a52.h"
11 struct hb_work_private_s
32 int out_discrete_channels;
36 int deca52Init( hb_work_object_t *, hb_job_t * );
37 int deca52Work( hb_work_object_t *, hb_buffer_t **, hb_buffer_t ** );
38 void deca52Close( hb_work_object_t * );
40 hb_work_object_t hb_deca52 =
49 /***********************************************************************
51 **********************************************************************/
52 static hb_buffer_t * Decode( hb_work_object_t * w );
54 /***********************************************************************
56 ***********************************************************************
57 * Allocate the work object, initialize liba52
58 **********************************************************************/
59 int deca52Init( hb_work_object_t * w, hb_job_t * job )
61 hb_work_private_t * pv = calloc( 1, sizeof( hb_work_private_t ) );
66 pv->list = hb_list_init();
67 pv->state = a52_init( 0 );
69 /* Decide what format we want out of a52dec
70 work.c has already done some of this deduction for us in do_job() */
72 pv->flags_out = HB_AMIXDOWN_GET_A52_FORMAT(w->amixdown);
74 /* pass the number of channels used into the private work data */
75 /* will only be actually used if we're not doing AC3 passthru */
76 pv->out_discrete_channels = HB_AMIXDOWN_GET_DISCRETE_CHANNEL_COUNT(w->amixdown);
83 /***********************************************************************
85 ***********************************************************************
87 **********************************************************************/
88 void deca52Close( hb_work_object_t * w )
90 hb_work_private_t * pv = w->private_data;
91 a52_free( pv->state );
92 hb_list_empty( &pv->list );
94 w->private_data = NULL;
97 /***********************************************************************
99 ***********************************************************************
100 * Add the given buffer to the data we already have, and decode as much
102 **********************************************************************/
103 int deca52Work( hb_work_object_t * w, hb_buffer_t ** buf_in,
104 hb_buffer_t ** buf_out )
106 hb_work_private_t * pv = w->private_data;
109 hb_list_add( pv->list, *buf_in );
112 /* If we got more than a frame, chain raw buffers */
113 *buf_out = buf = Decode( w );
116 buf->next = Decode( w );
123 /***********************************************************************
125 ***********************************************************************
127 **********************************************************************/
128 static hb_buffer_t * Decode( hb_work_object_t * w )
130 hb_work_private_t * pv = w->private_data;
135 /* Get a frame header if don't have one yet */
138 while( hb_list_bytes( pv->list ) >= 7 )
140 /* We have 7 bytes, check if this is a correct header */
141 hb_list_seebytes( pv->list, pv->frame, 7 );
142 pv->size = a52_syncinfo( pv->frame, &pv->flags_in, &pv->rate,
149 hb_log( "a52_syncinfo ok" );
159 hb_log( "a52_syncinfo failed" );
163 /* Try one byte later */
164 hb_list_getbytes( pv->list, pv->frame, 1, NULL, NULL );
169 hb_list_bytes( pv->list ) < pv->size )
175 /* Get the whole frame */
176 hb_list_getbytes( pv->list, pv->frame, pv->size, &pts, &pos );
178 /* AC3 passthrough: don't decode the AC3 frame */
179 if( pv->job->acodec & HB_ACODEC_AC3 )
181 buf = hb_buffer_init( pv->size );
182 memcpy( buf->data, pv->frame, pv->size );
183 buf->start = pts + ( pos / pv->size ) * 6 * 256 * 90000 / pv->rate;
184 buf->stop = buf->start + 6 * 256 * 90000 / pv->rate;
190 a52_frame( pv->state, pv->frame, &pv->flags_out, &pv->level, 0 );
192 /* 6 blocks per frame, 256 samples per block, channelsused channels */
193 buf = hb_buffer_init( 6 * 256 * pv->out_discrete_channels * sizeof( float ) );
194 buf->start = pts + ( pos / pv->size ) * 6 * 256 * 90000 / pv->rate;
195 buf->stop = buf->start + 6 * 256 * 90000 / pv->rate;
197 for( i = 0; i < 6; i++ )
199 sample_t * samples_in;
202 a52_block( pv->state );
203 samples_in = a52_samples( pv->state );
204 samples_out = ((float *) buf->data) + 256 * pv->out_discrete_channels * i;
207 for( j = 0; j < 256; j++ )
209 for ( k = 0; k < pv->out_discrete_channels; k++ )
211 samples_out[(pv->out_discrete_channels*j)+k] = samples_in[(256*k)+j]; // DJA