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aacdec: Add support for LD (Low Delay) AAC

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pull/36/head
Alex Converse 11 years ago
parent 5cdefc0207
commit 1914e6f010
6 changed files with 105 additions and 5 deletions
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  1. 1
      Changelog
  2. 1
      libavcodec/aac.h
  3. 63
      libavcodec/aacdec.c
  4. 36
      libavcodec/aactab.c
  5. 3
      libavcodec/aactab.h
  6. 2
      libavcodec/version.h

1
Changelog
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@ -35,6 +35,7 @@ version 10:
- incomplete Voxware MetaSound decoder
- WebP decoder
- Error Resilient AAC syntax (ER AAC LC) decoding
- Low Delay AAC (ER AAC LD) decoding
version 9:

1
libavcodec/aac.h
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@ -289,6 +289,7 @@ typedef struct AACContext {
*/
FFTContext mdct;
FFTContext mdct_small;
FFTContext mdct_ld;
FFTContext mdct_ltp;
FmtConvertContext fmt_conv;
AVFloatDSPContext fdsp;

63
libavcodec/aacdec.c
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@ -817,6 +817,13 @@ static int decode_audio_specific_config(AACContext *ac,
m4ac->sampling_index);
return AVERROR_INVALIDDATA;
}
if (m4ac->object_type == AOT_ER_AAC_LD &&
(m4ac->sampling_index < 3 || m4ac->sampling_index > 7)) {
av_log(avctx, AV_LOG_ERROR,
"invalid low delay sampling rate index %d\n",
m4ac->sampling_index);
return AVERROR_INVALIDDATA;
}
skip_bits_long(&gb, i);
@ -825,6 +832,7 @@ static int decode_audio_specific_config(AACContext *ac,
case AOT_AAC_LC:
case AOT_AAC_LTP:
case AOT_ER_AAC_LC:
case AOT_ER_AAC_LD:
if ((ret = decode_ga_specific_config(ac, avctx, &gb,
m4ac, m4ac->chan_config)) < 0)
return ret;
@ -985,12 +993,15 @@ static av_cold int aac_decode_init(AVCodecContext *avctx)
352);
ff_mdct_init(&ac->mdct, 11, 1, 1.0 / (32768.0 * 1024.0));
ff_mdct_init(&ac->mdct_ld, 10, 1, 1.0 / (32768.0 * 512.0));
ff_mdct_init(&ac->mdct_small, 8, 1, 1.0 / (32768.0 * 128.0));
ff_mdct_init(&ac->mdct_ltp, 11, 0, -2.0 * 32768.0);
// window initialization
ff_kbd_window_init(ff_aac_kbd_long_1024, 4.0, 1024);
ff_kbd_window_init(ff_aac_kbd_long_512, 4.0, 512);
ff_kbd_window_init(ff_aac_kbd_short_128, 6.0, 128);
ff_init_ff_sine_windows(10);
ff_init_ff_sine_windows( 9);
ff_init_ff_sine_windows( 7);
cbrt_tableinit();
@ -1063,6 +1074,14 @@ static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics,
}
ics->window_sequence[1] = ics->window_sequence[0];
ics->window_sequence[0] = get_bits(gb, 2);
if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD &&
ics->window_sequence[0] != ONLY_LONG_SEQUENCE) {
av_log(ac->avctx, AV_LOG_ERROR,
"AAC LD is only defined for ONLY_LONG_SEQUENCE but "
"window sequence %d found.\n", ics->window_sequence[0]);
ics->window_sequence[0] = ONLY_LONG_SEQUENCE;
return AVERROR_INVALIDDATA;
}
ics->use_kb_window[1] = ics->use_kb_window[0];
ics->use_kb_window[0] = get_bits1(gb);
ics->num_window_groups = 1;
@ -1086,8 +1105,15 @@ static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics,
} else {
ics->max_sfb = get_bits(gb, 6);
ics->num_windows = 1;
if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD) {
ics->swb_offset = ff_swb_offset_512[ac->oc[1].m4ac.sampling_index];
ics->num_swb = ff_aac_num_swb_512[ac->oc[1].m4ac.sampling_index];
if (!ics->num_swb || !ics->swb_offset)
return AVERROR_BUG;
} else {
ics->swb_offset = ff_swb_offset_1024[ac->oc[1].m4ac.sampling_index];
ics->num_swb = ff_aac_num_swb_1024[ac->oc[1].m4ac.sampling_index];
}
ics->tns_max_bands = ff_tns_max_bands_1024[ac->oc[1].m4ac.sampling_index];
ics->predictor_present = get_bits1(gb);
ics->predictor_reset_group = 0;
@ -1102,6 +1128,11 @@ static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics,
"Prediction is not allowed in AAC-LC.\n");
return AVERROR_INVALIDDATA;
} else {
if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD) {
av_log(ac->avctx, AV_LOG_ERROR,
"LTP in ER AAC LD not yet implemented.\n");
return AVERROR_PATCHWELCOME;
}
if ((ics->ltp.present = get_bits(gb, 1)))
decode_ltp(&ics->ltp, gb, ics->max_sfb);
}
@ -2314,6 +2345,25 @@ static void imdct_and_windowing(AACContext *ac, SingleChannelElement *sce)
}
}
static void imdct_and_windowing_ld(AACContext *ac, SingleChannelElement *sce)
{
IndividualChannelStream *ics = &sce->ics;
float *in = sce->coeffs;
float *out = sce->ret;
float *saved = sce->saved;
const float *lwindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_long_512 : ff_sine_512;
float *buf = ac->buf_mdct;
// imdct
ac->mdct.imdct_half(&ac->mdct_ld, buf, in);
// window overlapping
ac->fdsp.vector_fmul_window(out, saved, buf, lwindow_prev, 256);
// buffer update
memcpy(saved, buf + 256, 256 * sizeof(float));
}
/**
* Apply dependent channel coupling (applied before IMDCT).
*
@ -2410,6 +2460,11 @@ static void apply_channel_coupling(AACContext *ac, ChannelElement *cc,
static void spectral_to_sample(AACContext *ac)
{
int i, type;
void (*imdct_and_window)(AACContext *ac, SingleChannelElement *sce);
if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD)
imdct_and_window = imdct_and_windowing_ld;
else
imdct_and_window = imdct_and_windowing;
for (type = 3; type >= 0; type--) {
for (i = 0; i < MAX_ELEM_ID; i++) {
ChannelElement *che = ac->che[type][i];
@ -2431,11 +2486,11 @@ static void spectral_to_sample(AACContext *ac)
if (type <= TYPE_CPE)
apply_channel_coupling(ac, che, type, i, BETWEEN_TNS_AND_IMDCT, apply_dependent_coupling);
if (type != TYPE_CCE || che->coup.coupling_point == AFTER_IMDCT) {
imdct_and_windowing(ac, &che->ch[0]);
imdct_and_window(ac, &che->ch[0]);
if (ac->oc[1].m4ac.object_type == AOT_AAC_LTP)
update_ltp(ac, &che->ch[0]);
if (type == TYPE_CPE) {
imdct_and_windowing(ac, &che->ch[1]);
imdct_and_window(ac, &che->ch[1]);
if (ac->oc[1].m4ac.object_type == AOT_AAC_LTP)
update_ltp(ac, &che->ch[1]);
}
@ -2503,6 +2558,9 @@ static int aac_decode_er_frame(AVCodecContext *avctx, void *data,
int samples = 1024;
int chan_config = ac->oc[1].m4ac.chan_config;
if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD)
samples >>= 1;
ac->frame = data;
if ((err = frame_configure_elements(avctx)) < 0)
@ -2757,6 +2815,7 @@ static av_cold int aac_decode_close(AVCodecContext *avctx)
ff_mdct_end(&ac->mdct);
ff_mdct_end(&ac->mdct_small);
ff_mdct_end(&ac->mdct_ld);
ff_mdct_end(&ac->mdct_ltp);
return 0;
}

36
libavcodec/aactab.c
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@ -34,12 +34,17 @@
#include <stdint.h>
DECLARE_ALIGNED(32, float, ff_aac_kbd_long_1024)[1024];
DECLARE_ALIGNED(32, float, ff_aac_kbd_long_512 )[512];
DECLARE_ALIGNED(32, float, ff_aac_kbd_short_128)[128];
const uint8_t ff_aac_num_swb_1024[] = {
41, 41, 47, 49, 49, 51, 47, 47, 43, 43, 43, 40, 40
};
const uint8_t ff_aac_num_swb_512[] = {
0, 0, 0, 36, 36, 37, 31, 31, 0, 0, 0, 0, 0
};
const uint8_t ff_aac_num_swb_128[] = {
12, 12, 12, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15
};
@ -1114,6 +1119,14 @@ static const uint16_t swb_offset_1024_48[] = {
928, 1024
};
static const uint16_t swb_offset_512_48[] = {
0, 4, 8, 12, 16, 20, 24, 28,
32, 36, 40, 44, 48, 52, 56, 60,
68, 76, 84, 92, 100, 112, 124, 136,
148, 164, 184, 208, 236, 268, 300, 332,
364, 396, 428, 460, 512
};
static const uint16_t swb_offset_128_48[] = {
0, 4, 8, 12, 16, 20, 28, 36,
44, 56, 68, 80, 96, 112, 128
@ -1129,6 +1142,14 @@ static const uint16_t swb_offset_1024_32[] = {
928, 960, 992, 1024
};
static const uint16_t swb_offset_512_32[] = {
0, 4, 8, 12, 16, 20, 24, 28,
32, 36, 40, 44, 48, 52, 56, 64,
72, 80, 88, 96, 108, 120, 132, 144,
160, 176, 192, 212, 236, 260, 288, 320,
352, 384, 416, 448, 480, 512
};
static const uint16_t swb_offset_1024_24[] = {
0, 4, 8, 12, 16, 20, 24, 28,
32, 36, 40, 44, 52, 60, 68, 76,
@ -1138,6 +1159,13 @@ static const uint16_t swb_offset_1024_24[] = {
600, 652, 704, 768, 832, 896, 960, 1024
};
static const uint16_t swb_offset_512_24[] = {
0, 4, 8, 12, 16, 20, 24, 28,
32, 36, 40, 44, 52, 60, 68, 80,
92, 104, 120, 140, 164, 192, 224, 256,
288, 320, 352, 384, 416, 448, 480, 512,
};
static const uint16_t swb_offset_128_24[] = {
0, 4, 8, 12, 16, 20, 24, 28,
36, 44, 52, 64, 76, 92, 108, 128
@ -1179,6 +1207,14 @@ const uint16_t * const ff_swb_offset_1024[] = {
swb_offset_1024_8
};
const uint16_t * const ff_swb_offset_512[] = {
NULL, NULL, NULL,
swb_offset_512_48, swb_offset_512_48, swb_offset_512_32,
swb_offset_512_24, swb_offset_512_24, NULL,
NULL, NULL, NULL,
NULL
};
const uint16_t * const ff_swb_offset_128[] = {
/* The last entry on the following row is swb_offset_128_64 but is a
duplicate of swb_offset_128_96. */

3
libavcodec/aactab.h
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@ -45,6 +45,7 @@
* @{
*/
DECLARE_ALIGNED(32, extern float, ff_aac_kbd_long_1024)[1024];
DECLARE_ALIGNED(32, extern float, ff_aac_kbd_long_512 )[512];
DECLARE_ALIGNED(32, extern float, ff_aac_kbd_short_128)[128];
// @}
@ -52,6 +53,7 @@ DECLARE_ALIGNED(32, extern float, ff_aac_kbd_short_128)[128];
* @{
*/
extern const uint8_t ff_aac_num_swb_1024[];
extern const uint8_t ff_aac_num_swb_512 [];
extern const uint8_t ff_aac_num_swb_128 [];
// @}
@ -69,6 +71,7 @@ extern const float *ff_aac_codebook_vector_vals[];
extern const uint16_t *ff_aac_codebook_vector_idx[];
extern const uint16_t * const ff_swb_offset_1024[13];
extern const uint16_t * const ff_swb_offset_512 [13];
extern const uint16_t * const ff_swb_offset_128 [13];
extern const uint8_t ff_tns_max_bands_1024[13];

2
libavcodec/version.h
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@ -27,7 +27,7 @@
*/
#define LIBAVCODEC_VERSION_MAJOR 55
#define LIBAVCODEC_VERSION_MINOR 19
#define LIBAVCODEC_VERSION_MINOR 20
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \

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