ref: 3501993184b7b711ab99d442ac651a6fb1310b6f
dir: /libfaad/decoder.c/
/*
** FAAD - Freeware Advanced Audio Decoder
** Copyright (C) 2002 M. Bakker
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
**
** This program 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 General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
** $Id: decoder.c,v 1.5 2002/01/19 16:19:54 menno Exp $
**/
#include <stdlib.h>
#include <memory.h>
#include "decoder.h"
#include "syntax.h"
#include "specrec.h"
#include "data.h"
#include "tns.h"
#include "pns.h"
#include "is.h"
#include "ms.h"
#include "ic_predict.h"
#include "lt_predict.h"
#include "drc.h"
#include "error.h"
#include "output.h"
#ifdef ANALYSIS
int dbg_count;
#endif
char* FAADAPI faacDecGetErrorMessage(int errcode)
{
return err_msg[errcode];
}
faacDecHandle FAADAPI faacDecOpen()
{
int i;
faacDecHandle hDecoder = NULL;
if ((hDecoder = (faacDecHandle)malloc(sizeof(faacDecStruct))) == NULL)
return NULL;
memset(hDecoder, 0, sizeof(faacDecStruct));
hDecoder->config.outputFormat = FAAD_FMT_16BIT;
hDecoder->config.defObjectType = MAIN;
hDecoder->config.defSampleRate = 44100; /* Default: 44.1kHz */
hDecoder->adts_header_present = 0;
hDecoder->adif_header_present = 0;
hDecoder->frame = 0;
hDecoder->sample_buffer = NULL;
for (i = 0; i < MAX_CHANNELS; i++)
{
hDecoder->window_shape_prev[i] = 0;
hDecoder->time_state[i] = NULL;
hDecoder->time_out[i] = NULL;
hDecoder->pred_stat[i] = NULL;
hDecoder->lt_pred_stat[i] = NULL;
}
init_drc(&hDecoder->drc, 1.0f, 1.0f);
filter_bank_init(&hDecoder->fb);
#if IQ_TABLE_SIZE && POW_TABLE_SIZE
build_tables(hDecoder->iq_table, hDecoder->pow2_table);
#elif !IQ_TABLE_SIZE && POW_TABLE_SIZE
build_tables(NULL, hDecoder->pow2_table);
#elif IQ_TABLE_SIZE && !POW_TABLE_SIZE
build_tables(hDecoder->iq_table, NULL);
#endif
return hDecoder;
}
faacDecConfigurationPtr FAADAPI faacDecGetCurrentConfiguration(faacDecHandle hDecoder)
{
faacDecConfigurationPtr config = &(hDecoder->config);
return config;
}
int FAADAPI faacDecSetConfiguration(faacDecHandle hDecoder,
faacDecConfigurationPtr config)
{
hDecoder->config.defObjectType = config->defObjectType;
hDecoder->config.defSampleRate = config->defSampleRate;
hDecoder->config.outputFormat = config->outputFormat;
/* OK */
return 1;
}
/* Returns the sample rate index */
static int get_sr_index(unsigned long samplerate)
{
if (92017 <= samplerate) return 0;
if (75132 <= samplerate) return 1;
if (55426 <= samplerate) return 2;
if (46009 <= samplerate) return 3;
if (37566 <= samplerate) return 4;
if (27713 <= samplerate) return 5;
if (23004 <= samplerate) return 6;
if (18783 <= samplerate) return 7;
if (13856 <= samplerate) return 8;
if (11502 <= samplerate) return 9;
if (9391 <= samplerate) return 10;
return 11;
}
int FAADAPI faacDecInit(faacDecHandle hDecoder, unsigned char *buffer,
unsigned long *samplerate, unsigned long *channels)
{
bitfile ld;
adif_header adif;
adts_header adts;
hDecoder->sf_index = get_sr_index(hDecoder->config.defSampleRate);
hDecoder->object_type = hDecoder->config.defObjectType;
if (buffer != NULL)
{
faad_initbits(&ld, buffer);
/* Check if an ADIF header is present */
if ((buffer[0] == 'A') && (buffer[1] == 'D') &&
(buffer[2] == 'I') && (buffer[3] == 'F'))
{
hDecoder->adif_header_present = 1;
get_adif_header(&adif, &ld);
hDecoder->sf_index = adif.pce.sf_index;
hDecoder->object_type = adif.pce.object_type;
*samplerate = sample_rates[hDecoder->sf_index];
*channels = adif.pce.channels;
return bit2byte(faad_get_processed_bits(&ld));
/* Check if an ADTS header is present */
} else if (faad_showbits(&ld, 12) == 0xfff) {
hDecoder->adts_header_present = 1;
adts_frame(&adts, &ld);
hDecoder->sf_index = adts.sf_index;
hDecoder->object_type = adts.profile;
*samplerate = sample_rates[hDecoder->sf_index];
*channels = (adts.channel_configuration > 6) ?
2 : adts.channel_configuration;
return 0;
}
}
*samplerate = sample_rates[hDecoder->sf_index];
*channels = 2;
return 0;
}
static unsigned long ObjectTypesTable[32] = {0, 1, 1, 1, 1, };
int parse_audio_decoder_specific_info(faacDecHandle hDecoder,
unsigned char *pBuffer,
unsigned long *samplerate,
unsigned long *channels)
{
bitfile ld;
unsigned long ObjectTypeIndex, SamplingFrequencyIndex,
ChannelsConfiguration;
faad_initbits(&ld, pBuffer);
faad_byte_align(&ld);
ObjectTypeIndex = faad_getbits(&ld, 5
DEBUGVAR(1,1,"parse_audio_decoder_specific_info(): ObjectTypeIndex"));
SamplingFrequencyIndex = faad_getbits(&ld, 4
DEBUGVAR(1,2,"parse_audio_decoder_specific_info(): SamplingFrequencyIndex"));
ChannelsConfiguration = faad_getbits(&ld, 4
DEBUGVAR(1,3,"parse_audio_decoder_specific_info(): ChannelsConfiguration"));
if (ObjectTypesTable[ObjectTypeIndex] != 1)
{
return -1;
}
*samplerate = sample_rates[SamplingFrequencyIndex];
if (*samplerate == 0)
{
return -2;
}
*channels = ChannelsConfiguration;
hDecoder->sf_index = SamplingFrequencyIndex;
hDecoder->object_type = ObjectTypeIndex - 1;
if(ChannelsConfiguration > 7)
{
return -3;
}
/* get GASpecificConfig */
return 0;
}
/* Init the library using a DecoderSpecificInfo */
int FAADAPI faacDecInit2(faacDecHandle hDecoder, unsigned char *pBuffer,
unsigned long SizeOfDecoderSpecificInfo,
unsigned long *samplerate, unsigned long *channels)
{
int rc;
hDecoder->adif_header_present = 0;
hDecoder->adts_header_present = 0;
if((hDecoder == NULL)
|| (pBuffer == NULL)
|| (SizeOfDecoderSpecificInfo < 2)
|| (samplerate == NULL)
|| (channels == NULL))
{
return -1;
}
rc = parse_audio_decoder_specific_info(hDecoder, pBuffer,
samplerate, channels);
if (rc != 0)
{
return rc;
}
return 0;
}
void FAADAPI faacDecClose(faacDecHandle hDecoder)
{
int i;
for (i = 0; i < MAX_CHANNELS; i++)
{
if (hDecoder->time_state[i]) free(hDecoder->time_state[i]);
if (hDecoder->time_out[i]) free(hDecoder->time_out[i]);
if (hDecoder->pred_stat[i]) free(hDecoder->pred_stat[i]);
if (hDecoder->lt_pred_stat[i]) free(hDecoder->lt_pred_stat[i]);
}
filter_bank_end(&hDecoder->fb);
if (hDecoder->sample_buffer) free(hDecoder->sample_buffer);
if (hDecoder) free(hDecoder);
}
void* FAADAPI faacDecDecode(faacDecHandle hDecoder,
faacDecFrameInfo *hInfo,
unsigned char *buffer)
{
int id_syn_ele, ele, ch, i;
adts_header adts;
int channels, ch_ele;
bitfile *ld = malloc(sizeof(bitfile));
/* local copys of globals */
int sf_index = hDecoder->sf_index;
int object_type = hDecoder->object_type;
pred_state **pred_stat = hDecoder->pred_stat;
float **lt_pred_stat = hDecoder->lt_pred_stat;
#if IQ_TABLE_SIZE
float *iq_table = hDecoder->iq_table;
#else
float *iq_table = NULL;
#endif
#if POW_TABLE_SIZE
float *pow2_table = hDecoder->pow2_table;
#else
float *pow2_table = NULL;
#endif
int *window_shape_prev = hDecoder->window_shape_prev;
float **time_state = hDecoder->time_state;
float **time_out = hDecoder->time_out;
fb_info *fb = &hDecoder->fb;
drc_info *drc = &hDecoder->drc;
int outputFormat = hDecoder->config.outputFormat;
program_config pce;
element *syntax_elements[MAX_SYNTAX_ELEMENTS];
short *spec_data[MAX_CHANNELS];
float *spec_coef[MAX_CHANNELS];
void *sample_buffer;
memset(hInfo, 0, sizeof(faacDecFrameInfo));
/* initialize the bitstream */
faad_initbits(ld, buffer);
if (hDecoder->adts_header_present)
{
if ((hInfo->error = adts_frame(&adts, ld)) > 0)
goto error;
/* MPEG2 does byte_alignment() here,
* but ADTS header is always multiple of 8 bits in MPEG2
* so not needed to actually do it.
*/
}
ele = 0;
channels = 0;
ch_ele = 0;
#ifdef ANALYSIS
dbg_count = 0;
#endif
/* Table 4.4.3: raw_data_block() */
while ((id_syn_ele = faad_getbits(ld, LEN_SE_ID
DEBUGVAR(1,4,"faacDecDecode(): id_syn_ele"))) != ID_END)
{
switch (id_syn_ele) {
case ID_SCE:
case ID_LFE:
spec_data[channels] = (short*)malloc(1024*sizeof(short));
spec_coef[channels] = (float*)malloc(1024*sizeof(float));
syntax_elements[ch_ele] = (element*)malloc(sizeof(element));
memset(syntax_elements[ch_ele], 0, sizeof(element));
syntax_elements[ch_ele]->ele_id = id_syn_ele;
syntax_elements[ch_ele]->channel = channels;
if ((hInfo->error = single_lfe_channel_element(syntax_elements[ch_ele],
ld, spec_data[channels], sf_index, object_type)) > 0)
{
/* to make sure everything gets deallocated */
channels++; ch_ele++;
goto error;
}
channels++;
ch_ele++;
break;
case ID_CPE:
spec_data[channels] = (short*)malloc(1024*sizeof(short));
spec_data[channels+1] = (short*)malloc(1024*sizeof(short));
spec_coef[channels] = (float*)malloc(1024*sizeof(float));
spec_coef[channels+1] = (float*)malloc(1024*sizeof(float));
syntax_elements[ch_ele] = (element*)malloc(sizeof(element));
memset(syntax_elements[ch_ele], 0, sizeof(element));
syntax_elements[ch_ele]->ele_id = id_syn_ele;
syntax_elements[ch_ele]->channel = channels;
syntax_elements[ch_ele]->paired_channel = channels+1;
if ((hInfo->error = channel_pair_element(syntax_elements[ch_ele],
ld, spec_data[channels], spec_data[channels+1],
sf_index, object_type)) > 0)
{
/* to make sure everything gets deallocated */
channels+=2; ch_ele++;
goto error;
}
channels += 2;
ch_ele++;
break;
case ID_CCE: /* not implemented yet */
hInfo->error = 6;
goto error;
break;
case ID_DSE:
data_stream_element(ld);
break;
case ID_PCE:
if ((hInfo->error = program_config_element(&pce, ld)) > 0)
goto error;
break;
case ID_FIL:
if ((hInfo->error = fill_element(ld, drc)) > 0)
goto error;
break;
}
ele++;
}
/* no more bit reading after this */
faad_byte_align(ld);
hInfo->bytesconsumed = bit2byte(faad_get_processed_bits(ld));
if (ld) free(ld);
ld = NULL;
/* number of samples in this frame */
hInfo->samples = 1024*channels;
/* number of samples in this frame */
hInfo->channels = channels;
if (hDecoder->sample_buffer == NULL)
hDecoder->sample_buffer = malloc(1024*channels*sizeof(float));
sample_buffer = hDecoder->sample_buffer;
/* noiseless coding is done, the rest of the tools come now */
for (ch = 0; ch < channels; ch++)
{
ic_stream *ics;
/* find the syntax element to which this channel belongs */
for (i = 0; i < ch_ele; i++)
{
if (syntax_elements[i]->channel == ch)
{
ics = &syntax_elements[i]->ics1;
break;
} else if (syntax_elements[i]->paired_channel == ch) {
ics = &syntax_elements[i]->ics2;
break;
}
}
/* inverse quantization */
inverse_quantization(spec_coef[ch], spec_data[ch], iq_table);
/* apply scalefactors */
apply_scalefactors(ics, spec_coef[ch], pow2_table);
/* deinterleave short block grouping */
if (ics->window_sequence == EIGHT_SHORT_SEQUENCE)
quant_to_spec(ics, spec_coef[ch]);
}
/* Because for ms and is both channels spectral coefficients are needed
we have to restart running through all channels here.
*/
for (ch = 0; ch < channels; ch++)
{
int pch = 0;
int right_channel;
ic_stream *ics, *icsr;
ltp_info *ltp;
/* find the syntax element to which this channel belongs */
for (i = 0; i < ch_ele; i++)
{
if (syntax_elements[i]->channel == ch)
{
ics = &syntax_elements[i]->ics1;
icsr = &syntax_elements[i]->ics2;
ltp = &(ics->ltp);
pch = syntax_elements[i]->paired_channel;
right_channel = 0;
break;
} else if (syntax_elements[i]->paired_channel == ch) {
ics = &syntax_elements[i]->ics2;
ltp = &(ics->ltp2);
right_channel = 1;
break;
}
}
/* mid/side decoding */
if (!right_channel)
ms_decode(ics, icsr, spec_coef[ch], spec_coef[pch]);
/* pns decoding */
pns_decode(ics, spec_coef[ch]);
/* intensity stereo decoding */
if (!right_channel)
is_decode(ics, icsr, spec_coef[ch], spec_coef[pch]);
/* MAIN object type prediction */
if (object_type == MAIN)
{
/* allocate the state only when needed */
if ((pred_stat[ch] == NULL) && ics->predictor_data_present)
{
pred_stat[ch] = malloc(1024 * sizeof(pred_state));
reset_all_predictors(pred_stat[ch]);
}
/* intra channel prediction */
if (pred_stat[ch] != NULL)
{
ic_prediction(ics, spec_coef[ch], pred_stat[ch]);
/* In addition, for scalefactor bands coded by perceptual
noise substitution the predictors belonging to the
corresponding spectral coefficients are reset.
*/
pns_reset_pred_state(ics, pred_stat[ch]);
}
} else if (object_type == LTP) {
/* allocate the state only when needed */
if ((lt_pred_stat[ch] == NULL) && ics->predictor_data_present)
{
lt_pred_stat[ch] = malloc(1024*3 * sizeof(float));
memset(lt_pred_stat[ch], 0, 1024*3 * sizeof(float));
}
/* long term prediction */
if (lt_pred_stat[ch] != NULL)
{
lt_prediction(ics, ltp, spec_coef[ch], lt_pred_stat[ch], fb,
ics->window_shape, window_shape_prev[ch],
sf_index, object_type);
}
}
/* tns decoding */
tns_decode_frame(ics, &ics->tns, sf_index, object_type, spec_coef[ch]);
/* drc decoding */
if (drc->present)
{
if (!drc->exclude_mask[ch] || !drc->excluded_chns_present)
drc_decode(drc, spec_coef[ch]);
}
if (time_state[ch] == NULL)
{
float *tp;
time_state[ch] = malloc(1024*sizeof(float));
tp = time_state[ch];
for (i = 1024/16-1; i >= 0; --i)
{
*tp++ = 0; *tp++ = 0; *tp++ = 0; *tp++ = 0;
*tp++ = 0; *tp++ = 0; *tp++ = 0; *tp++ = 0;
*tp++ = 0; *tp++ = 0; *tp++ = 0; *tp++ = 0;
*tp++ = 0; *tp++ = 0; *tp++ = 0; *tp++ = 0;
}
}
if (time_out[ch] == NULL)
{
time_out[ch] = malloc(1024*2*sizeof(float));
}
/* filter bank */
ifilter_bank(fb, ics->window_sequence, ics->window_shape,
window_shape_prev[ch], spec_coef[ch], time_state[ch],
time_out[ch]);
/* save window shape for next frame */
window_shape_prev[ch] = ics->window_shape;
if ((object_type == LTP) && (lt_pred_stat[ch] != NULL))
lt_update_state(lt_pred_stat[ch], time_out[ch], time_state[ch]);
}
sample_buffer = output_to_PCM(time_out, sample_buffer, channels,
outputFormat);
hDecoder->frame++;
if (hDecoder->frame <= 1)
hInfo->samples = 0;
/* cleanup */
for (ch = 0; ch < channels; ch++)
{
free(spec_coef[ch]);
free(spec_data[ch]);
}
for (i = 0; i < ch_ele; i++)
{
free(syntax_elements[i]);
}
#ifdef ANALYSIS
fflush(stdout);
#endif
return sample_buffer;
error:
/* free all memory that could have been allocated */
if (ld) free(ld);
/* cleanup */
for (ch = 0; ch < channels; ch++)
{
free(spec_coef[ch]);
free(spec_data[ch]);
}
for (i = 0; i < ch_ele; i++)
{
free(syntax_elements[i]);
}
#ifdef ANALYSIS
fflush(stdout);
#endif
return NULL;
}