codecs/aac.rs

   1 use nihav_core::formats::*;
   2 use nihav_core::frame::*;
   3 use nihav_core::codecs::*;
   4 use nihav_codec_support::dsp::mdct::IMDCT;
   5 use nihav_codec_support::dsp::window::*;
   6 use nihav_core::io::bitreader::*;
   7 use nihav_core::io::codebook::*;
   8 use std::fmt;
   9 use nihav_core::io::intcode::*;
  10 use std::mem;
  11 use std::ptr;
  12 use std::str::FromStr;
  13 use std::f32::consts;
  14
  15 #[allow(non_camel_case_types)]
  16 #[derive(Clone,Copy,PartialEq)]
  17 enum M4AType {
  18     None,
  19     Main,
  20     LC,
  21     SSR,
  22     LTP,
  23     SBR,
  24     Scalable,
  25     TwinVQ,
  26     CELP,
  27     HVXC,
  28     TTSI,
  29     MainSynth,
  30     WavetableSynth,
  31     GeneralMIDI,
  32     Algorithmic,
  33     ER_AAC_LC,
  34     ER_AAC_LTP,
  35     ER_AAC_Scalable,
  36     ER_TwinVQ,
  37     ER_BSAC,
  38     ER_AAC_LD,
  39     ER_CELP,
  40     ER_HVXC,
  41     ER_HILN,
  42     ER_Parametric,
  43     SSC,
  44     PS,
  45     MPEGSurround,
  46     Layer1,
  47     Layer2,
  48     Layer3,
  49     DST,
  50     ALS,
  51     SLS,
  52     SLSNonCore,
  53     ER_AAC_ELD,
  54     SMRSimple,
  55     SMRMain,
  56     Reserved,
  57     Unknown,
  58 }
  59
  60 const M4A_TYPES: &[M4AType] = &[
  61     M4AType::None,              M4AType::Main,      M4AType::LC,            M4AType::SSR,
  62     M4AType::LTP,               M4AType::SBR,       M4AType::Scalable,      M4AType::TwinVQ,
  63     M4AType::CELP,              M4AType::HVXC,      M4AType::Reserved,      M4AType::Reserved,
  64     M4AType::TTSI,              M4AType::MainSynth, M4AType::WavetableSynth, M4AType::GeneralMIDI,
  65     M4AType::Algorithmic,       M4AType::ER_AAC_LC, M4AType::Reserved,      M4AType::ER_AAC_LTP,
  66     M4AType::ER_AAC_Scalable,   M4AType::ER_TwinVQ, M4AType::ER_BSAC,       M4AType::ER_AAC_LD,
  67     M4AType::ER_CELP,           M4AType::ER_HVXC,   M4AType::ER_HILN,       M4AType::ER_Parametric,
  68     M4AType::SSC,               M4AType::PS,        M4AType::MPEGSurround,  M4AType::Reserved /*escape*/,
  69     M4AType::Layer1,            M4AType::Layer2,    M4AType::Layer3,        M4AType::DST,
  70     M4AType::ALS,               M4AType::SLS,       M4AType::SLSNonCore,    M4AType::ER_AAC_ELD,
  71     M4AType::SMRSimple,         M4AType::SMRMain,
  72 ];
  73 const M4A_TYPE_NAMES: &[&str] = &[
  74     "None", "AAC Main", "AAC LC", "AAC SSR", "AAC LTP", "SBR", "AAC Scalable", "TwinVQ", "CELP", "HVXC",
  75     /*"(reserved10)", "(reserved11)", */ "TTSI",
  76     "Main synthetic", "Wavetable synthesis", "General MIDI", "Algorithmic Synthesis and Audio FX",
  77     "ER AAC LC", /*"(reserved18)",*/ "ER AAC LTP", "ER AAC Scalable", "ER TwinVQ", "ER BSAC", "ER AAC LD",
  78     "ER CELP", "ER HVXC", "ER HILN", "ER Parametric", "SSC", "PS", "MPEG Surround", /*"(escape)",*/
  79     "Layer-1", "Layer-2", "Layer-3", "DST", "ALS", "SLS", "SLS non-core", "ER AAC ELD", "SMR Simple", "SMR Main",
  80     "(reserved)", "(unknown)",
  81 ];
  82
  83 impl fmt::Display for M4AType {
  84     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
  85         write!(f, "{}", M4A_TYPE_NAMES[*self as usize])
  86     }
  87 }
  88
  89 const AAC_SAMPLE_RATES: [u32; 16] = [
  90     96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050,
  91     16000, 12000, 11025,  8000,  7350, 0, 0, 0
  92 ];
  93
  94 const AAC_CHANNELS: [usize; 8] = [ 0, 1, 2, 3, 4, 5, 6, 8 ];
  95
  96 struct M4AInfo {
  97     otype:          M4AType,
  98     srate:          u32,
  99     channels:       usize,
 100     samples:        usize,
 101     sbr_ps_info:    Option<(u32, usize)>,
 102     sbr_present:    bool,
 103     ps_present:     bool,
 104 }
 105
 106 impl M4AInfo {
 107     fn new() -> Self {
 108         Self {
 109             otype:          M4AType::None,
 110             srate:          0,
 111             channels:       0,
 112             samples:        0,
 113             sbr_ps_info:    Option::None,
 114             sbr_present:    false,
 115             ps_present:     false,
 116         }
 117     }
 118     fn read_object_type(br: &mut BitReader) -> DecoderResult<M4AType> {
 119         let otypeidx;
 120         if br.peek(5) == 31 {
 121                                                           br.skip(5)?;
 122             otypeidx                                    = (br.read(6)? as usize) + 32;
 123         } else {
 124             otypeidx                                    = br.read(5)? as usize;
 125         }
 126         if otypeidx >= M4A_TYPES.len() {
 127             Ok(M4AType::Unknown)
 128         } else {
 129             Ok(M4A_TYPES[otypeidx])
 130         }
 131     }
 132     fn read_sampling_frequency(br: &mut BitReader) -> DecoderResult<u32> {
 133         if br.peek(4) == 15 {
 134             let srate                                   = br.read(24)?;
 135             Ok(srate)
 136         } else {
 137             let srate_idx                               = br.read(4)? as usize;
 138             Ok(AAC_SAMPLE_RATES[srate_idx])
 139         }
 140     }
 141     fn read_channel_config(br: &mut BitReader) -> DecoderResult<usize> {
 142         let chidx                                       = br.read(4)? as usize;
 143         if chidx < AAC_CHANNELS.len() {
 144             Ok(AAC_CHANNELS[chidx])
 145         } else {
 146             Ok(chidx)
 147         }
 148     }
 149     fn read(&mut self, src: &[u8]) -> DecoderResult<()> {
 150         let mut br = BitReader::new(src, BitReaderMode::BE);
 151         self.otype = Self::read_object_type(&mut br)?;
 152         self.srate = Self::read_sampling_frequency(&mut br)?;
 153         validate!(self.srate > 0);
 154         self.channels = Self::read_channel_config(&mut br)?;
 155
 156         if (self.otype == M4AType::SBR) || (self.otype == M4AType::PS) {
 157             let ext_srate = Self::read_sampling_frequency(&mut br)?;
 158             self.otype = Self::read_object_type(&mut br)?;
 159             let ext_chans;
 160             if self.otype == M4AType::ER_BSAC {
 161                 ext_chans = Self::read_channel_config(&mut br)?;
 162             } else {
 163                 ext_chans = 0;
 164             }
 165             self.sbr_ps_info = Some((ext_srate, ext_chans));
 166         }
 167
 168         match self.otype {
 169             M4AType::Main | M4AType::LC | M4AType::SSR | M4AType::Scalable | M4AType::TwinVQ |
 170             M4AType::ER_AAC_LC | M4AType::ER_AAC_LTP | M4AType::ER_AAC_Scalable | M4AType::ER_TwinVQ |
 171             M4AType::ER_BSAC | M4AType::ER_AAC_LD => {
 172                 // GASpecificConfig
 173                     let short_frame                     = br.read_bool()?;
 174                     self.samples = if short_frame { 960 } else { 1024 };
 175                     let depends_on_core                 = br.read_bool()?;
 176                     if depends_on_core {
 177                         let _delay                      = br.read(14)?;
 178                     }
 179                     let extension_flag                  = br.read_bool()?;
 180                     if self.channels == 0 {
 181                         unimplemented!("program config element");
 182                     }
 183                     if (self.otype == M4AType::Scalable) || (self.otype == M4AType::ER_AAC_Scalable) {
 184                         let _layer                      = br.read(3)?;
 185                     }
 186                     if extension_flag {
 187                         if self.otype == M4AType::ER_BSAC {
 188                             let _num_subframes          = br.read(5)? as usize;
 189                             let _layer_length           = br.read(11)?;
 190                         }
 191                         if (self.otype == M4AType::ER_AAC_LC) ||
 192                            (self.otype == M4AType::ER_AAC_LTP) ||
 193                            (self.otype == M4AType::ER_AAC_Scalable) ||
 194                            (self.otype == M4AType::ER_AAC_LD) {
 195                             let _section_data_resilience    = br.read_bool()?;
 196                             let _scalefactors_resilience    = br.read_bool()?;
 197                             let _spectral_data_resilience   = br.read_bool()?;
 198                         }
 199                         let extension_flag3             = br.read_bool()?;
 200                         if extension_flag3 {
 201                             unimplemented!("version3 extensions");
 202                         }
 203                     }
 204                 },
 205             M4AType::CELP => { unimplemented!("CELP config"); },
 206             M4AType::HVXC => { unimplemented!("HVXC config"); },
 207             M4AType::TTSI => { unimplemented!("TTS config"); },
 208             M4AType::MainSynth | M4AType::WavetableSynth | M4AType::GeneralMIDI | M4AType::Algorithmic => { unimplemented!("structured audio config"); },
 209             M4AType::ER_CELP => { unimplemented!("ER CELP config"); },
 210             M4AType::ER_HVXC => { unimplemented!("ER HVXC config"); },
 211             M4AType::ER_HILN | M4AType::ER_Parametric => { unimplemented!("parametric config"); },
 212             M4AType::SSC => { unimplemented!("SSC config"); },
 213             M4AType::MPEGSurround => {
 214                                                         br.skip(1)?; // sacPayloadEmbedding
 215                     unimplemented!("MPEG Surround config");
 216                 },
 217             M4AType::Layer1 | M4AType::Layer2 | M4AType::Layer3 => { unimplemented!("MPEG Layer 1/2/3 config"); },
 218             M4AType::DST => { unimplemented!("DST config"); },
 219             M4AType::ALS => {
 220                                                         br.skip(5)?; // fillBits
 221                     unimplemented!("ALS config");
 222                 },
 223             M4AType::SLS | M4AType::SLSNonCore => { unimplemented!("SLS config"); },
 224             M4AType::ER_AAC_ELD => { unimplemented!("ELD config"); },
 225             M4AType::SMRSimple | M4AType::SMRMain => { unimplemented!("symbolic music config"); },
 226             _ => {},
 227         };
 228         match self.otype {
 229             M4AType::ER_AAC_LC | M4AType::ER_AAC_LTP | M4AType::ER_AAC_Scalable | M4AType::ER_TwinVQ |
 230             M4AType::ER_BSAC | M4AType::ER_AAC_LD | M4AType::ER_CELP | M4AType::ER_HVXC |
 231             M4AType::ER_HILN | M4AType::ER_Parametric | M4AType::ER_AAC_ELD => {
 232                     let ep_config                       = br.read(2)?;
 233                     if (ep_config == 2) || (ep_config == 3) {
 234                         unimplemented!("error protection config");
 235                     }
 236                     if ep_config == 3 {
 237                         let direct_mapping              = br.read_bool()?;
 238                         validate!(direct_mapping);
 239                     }
 240                 },
 241             _ => {},
 242         };
 243         if self.sbr_ps_info.is_some() && (br.left() >= 16) {
 244             let sync                                    = br.read(11)?;
 245             if sync == 0x2B7 {
 246                 let ext_otype = Self::read_object_type(&mut br)?;
 247                 if ext_otype == M4AType::SBR {
 248                     self.sbr_present                    = br.read_bool()?;
 249                     if self.sbr_present {
 250                         let _ext_srate = Self::read_sampling_frequency(&mut br)?;
 251                         if br.left() >= 12 {
 252                             let sync                    = br.read(11)?;
 253                             if sync == 0x548 {
 254                                 self.ps_present         = br.read_bool()?;
 255                             }
 256                         }
 257                     }
 258                 }
 259                 if ext_otype == M4AType::PS {
 260                     self.sbr_present                    = br.read_bool()?;
 261                     if self.sbr_present {
 262                         let _ext_srate = Self::read_sampling_frequency(&mut br)?;
 263                     }
 264                     let _ext_channels = br.read(4)?;
 265                 }
 266             }
 267         }
 268
 269         Ok(())
 270     }
 271 }
 272
 273 impl fmt::Display for M4AInfo {
 274     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 275         write!(f, "MPEG 4 Audio {}, {} Hz, {} channels, {} samples per frame",
 276                self.otype, self.srate, self.channels, self.samples)
 277     }
 278 }
 279
 280 const MAX_WINDOWS:  usize = 8;
 281 const MAX_SFBS:     usize = 64;
 282
 283 #[derive(Clone,Copy)]
 284 struct ICSInfo {
 285     window_sequence:        u8,
 286     prev_window_sequence:   u8,
 287     window_shape:           bool,
 288     prev_window_shape:      bool,
 289     scale_factor_grouping:  [bool; MAX_WINDOWS],
 290     group_start:            [usize; MAX_WINDOWS],
 291     window_groups:          usize,
 292     num_windows:            usize,
 293     max_sfb:                usize,
 294     predictor_data:         Option<LTPData>,
 295     long_win:               bool,
 296 }
 297
 298 const ONLY_LONG_SEQUENCE:   u8 = 0;
 299 const LONG_START_SEQUENCE:  u8 = 1;
 300 const EIGHT_SHORT_SEQUENCE: u8 = 2;
 301 const LONG_STOP_SEQUENCE:   u8 = 3;
 302
 303 impl ICSInfo {
 304     fn new() -> Self {
 305         Self {
 306             window_sequence:        0,
 307             prev_window_sequence:   0,
 308             window_shape:           false,
 309             prev_window_shape:      false,
 310             scale_factor_grouping:  [false; MAX_WINDOWS],
 311             group_start:            [0; MAX_WINDOWS],
 312             num_windows:            0,
 313             window_groups:          0,
 314             max_sfb:                0,
 315             predictor_data:         None,
 316             long_win:               true,
 317         }
 318     }
 319     fn decode_ics_info(&mut self, br: &mut BitReader) -> DecoderResult<()> {
 320         self.prev_window_sequence = self.window_sequence;
 321         self.prev_window_shape    = self.window_shape;
 322         let ics_reserved_bit                            = br.read(1)?;
 323         validate!(ics_reserved_bit == 0);
 324         self.window_sequence                            = br.read(2)? as u8;
 325         match self.prev_window_sequence {
 326             ONLY_LONG_SEQUENCE | LONG_STOP_SEQUENCE => {
 327                     validate!((self.window_sequence == ONLY_LONG_SEQUENCE) ||
 328                               (self.window_sequence == LONG_START_SEQUENCE));
 329                 },
 330             LONG_START_SEQUENCE | EIGHT_SHORT_SEQUENCE => {
 331                     validate!((self.window_sequence == EIGHT_SHORT_SEQUENCE) ||
 332                               (self.window_sequence == LONG_STOP_SEQUENCE));
 333                 },
 334             _ => {},
 335         };
 336         self.window_shape                               = br.read_bool()?;
 337         self.window_groups = 1;
 338         if self.window_sequence == EIGHT_SHORT_SEQUENCE {
 339             self.long_win = false;
 340             self.num_windows = 8;
 341             self.max_sfb                                = br.read(4)? as usize;
 342             for i in 0..MAX_WINDOWS-1 {
 343                 self.scale_factor_grouping[i]           = br.read_bool()?;
 344                 if !self.scale_factor_grouping[i] {
 345                     self.group_start[self.window_groups] = i + 1;
 346                     self.window_groups += 1;
 347                 }
 348             }
 349         } else {
 350             self.long_win = true;
 351             self.num_windows = 1;
 352             self.max_sfb                                = br.read(6)? as usize;
 353             self.predictor_data = LTPData::read(br)?;
 354         }
 355         Ok(())
 356     }
 357     fn get_group_start(&self, g: usize) -> usize {
 358         if g == 0 {
 359             0
 360         } else if g >= self.window_groups {
 361             if self.long_win { 1 } else { 8 }
 362         } else {
 363             self.group_start[g]
 364         }
 365     }
 366 }
 367
 368 #[derive(Clone,Copy)]
 369 struct LTPData {
 370 }
 371
 372 impl LTPData {
 373     fn read(br: &mut BitReader) -> DecoderResult<Option<Self>> {
 374         let predictor_data_present                      = br.read_bool()?;
 375         if !predictor_data_present { return Ok(None); }
 376 unimplemented!("predictor data");
 377 /*
 378         if is_main {
 379             let predictor_reset                         = br.read_bool()?;
 380             if predictor_reset {
 381                 let predictor_reset_group_number        = br.read(5)?;
 382             }
 383             for sfb in 0..max_sfb.min(PRED_SFB_MAX) {
 384                 prediction_used[sfb]                    = br.read_bool()?;
 385             }
 386         } else {
 387             let ltp_data_present                        = br.read_bool()?;
 388             if ltp_data_present {
 389                 //ltp data
 390             }
 391             if common_window {
 392                 let ltp_data_present                    = br.read_bool()?;
 393                 if ltp_data_present {
 394                     //ltp data
 395                 }
 396             }
 397         }
 398         Ok(Some(Self { }))
 399 */
 400     }
 401 }
 402
 403 #[derive(Clone,Copy)]
 404 #[allow(dead_code)]
 405 struct PulseData {
 406     number_pulse:       usize,
 407     pulse_start_sfb:    usize,
 408     pulse_offset:       [u8; 4],
 409     pulse_amp:          [u8; 4],
 410 }
 411
 412 impl PulseData {
 413     fn read(br: &mut BitReader) -> DecoderResult<Option<Self>> {
 414         let pulse_data_present                          = br.read_bool()?;
 415         if !pulse_data_present { return Ok(None); }
 416
 417         let number_pulse                                = (br.read(2)? as usize) + 1;
 418         let pulse_start_sfb                             = br.read(6)? as usize;
 419         let mut pulse_offset: [u8; 4] = [0; 4];
 420         let mut pulse_amp: [u8; 4] = [0; 4];
 421         for i in 0..number_pulse {
 422             pulse_offset[i]                             = br.read(5)? as u8;
 423             pulse_amp[i]                                = br.read(4)? as u8;
 424         }
 425         Ok(Some(Self{ number_pulse, pulse_start_sfb, pulse_offset, pulse_amp }))
 426     }
 427 }
 428
 429 const TNS_MAX_ORDER: usize = 20;
 430 const TNS_MAX_LONG_BANDS: [usize; 12] = [ 31, 31, 34, 40, 42, 51, 46, 46, 42, 42, 42, 39 ];
 431 const TNS_MAX_SHORT_BANDS: [usize; 12] = [ 9, 9, 10, 14, 14, 14, 14, 14, 14, 14, 14, 14 ];
 432
 433 #[derive(Clone,Copy)]
 434 struct TNSCoeffs {
 435     length:     usize,
 436     order:      usize,
 437     direction:  bool,
 438     compress:   bool,
 439     coef:       [f32; TNS_MAX_ORDER + 1],
 440 }
 441
 442 impl TNSCoeffs {
 443     fn new() -> Self {
 444         Self {
 445             length: 0, order: 0, direction: false, compress: false, coef: [0.0; TNS_MAX_ORDER + 1],
 446         }
 447     }
 448     fn read(&mut self, br: &mut BitReader, long_win: bool, coef_res: bool, max_order: usize) -> DecoderResult<()> {
 449         self.length                                     = br.read(if long_win { 6 } else { 4 })? as usize;
 450         self.order                                      = br.read(if long_win { 5 } else { 3 })? as usize;
 451         validate!(self.order <= max_order);
 452         if self.order > 0 {
 453             self.direction                              = br.read_bool()?;
 454             self.compress                               = br.read_bool()?;
 455             let mut coef_bits = 3;
 456             if coef_res      { coef_bits += 1; }
 457             if self.compress { coef_bits -= 1; }
 458             let sign_mask = 1 << (coef_bits - 1);
 459             let neg_mask  = !(sign_mask * 2 - 1);
 460
 461             let fac_base = if coef_res { 1 << 3 } else { 1 << 2 } as f32;
 462             let iqfac   = (fac_base - 0.5) / (consts::PI / 2.0);
 463             let iqfac_m = (fac_base + 0.5) / (consts::PI / 2.0);
 464             let mut tmp: [f32; TNS_MAX_ORDER] = [0.0; TNS_MAX_ORDER];
 465             for el in tmp.iter_mut().take(self.order) {
 466                 let val                                 = br.read(coef_bits)? as i8;
 467                 let c = f32::from(if (val & sign_mask) != 0 { val | neg_mask } else { val });
 468                 *el = (if c >= 0.0 { c / iqfac } else { c / iqfac_m }).sin();
 469             }
 470             // convert to LPC coefficients
 471             let mut b: [f32; TNS_MAX_ORDER + 1] = [0.0; TNS_MAX_ORDER + 1];
 472             for m in 1..=self.order {
 473                 for i in 1..m {
 474                     b[i] = self.coef[i - 1] + tmp[m - 1] * self.coef[m - i - 1];
 475                 }
 476                 for i in 1..m {
 477                     self.coef[i - 1] = b[i];
 478                 }
 479                 self.coef[m - 1] = tmp[m - 1];
 480             }
 481         }
 482         Ok(())
 483     }
 484 }
 485
 486 #[derive(Clone,Copy)]
 487 #[allow(dead_code)]
 488 struct TNSData {
 489     n_filt:     [usize; MAX_WINDOWS],
 490     coef_res:   [bool; MAX_WINDOWS],
 491     coeffs:     [[TNSCoeffs; 4]; MAX_WINDOWS],
 492 }
 493
 494 impl TNSData {
 495     fn read(br: &mut BitReader, long_win: bool, num_windows: usize, max_order: usize) -> DecoderResult<Option<Self>> {
 496         let tns_data_present                            = br.read_bool()?;
 497         if !tns_data_present { return Ok(None); }
 498         let mut n_filt: [usize; MAX_WINDOWS] = [0; MAX_WINDOWS];
 499         let mut coef_res: [bool; MAX_WINDOWS] = [false; MAX_WINDOWS];
 500         let mut coeffs: [[TNSCoeffs; 4]; MAX_WINDOWS] = [[TNSCoeffs::new(); 4]; MAX_WINDOWS];
 501         for w in 0..num_windows {
 502             n_filt[w]                                   = br.read(if long_win { 2 } else { 1 })? as usize;
 503             if n_filt[w] != 0 {
 504                 coef_res[w]                             = br.read_bool()?;
 505             }
 506             for filt in 0..n_filt[w] {
 507                 coeffs[w][filt].read(br, long_win, coef_res[w], max_order)?;
 508             }
 509         }
 510         Ok(Some(Self { n_filt, coef_res, coeffs }))
 511     }
 512 }
 513
 514 #[derive(Clone,Copy)]
 515 #[allow(dead_code)]
 516 struct GainControlData {
 517     max_band:       u8,
 518 }
 519
 520 impl GainControlData {
 521     fn read(br: &mut BitReader) -> DecoderResult<Option<Self>> {
 522         let gain_control_data_present                   = br.read_bool()?;
 523         if !gain_control_data_present { return Ok(None); }
 524 unimplemented!("gain control data");
 525 /*        self.max_band                                   = br.read(2)? as u8;
 526         if window_sequence == ONLY_LONG_SEQUENCE {
 527             for bd in 0..max_band
 528 ...
 529         }
 530         Ok(Some(Self { }))*/
 531     }
 532 }
 533
 534 const ZERO_HCB:         u8 = 0;
 535 const FIRST_PAIR_HCB:   u8 = 5;
 536 const ESC_HCB:          u8 = 11;
 537 const RESERVED_HCB:     u8 = 12;
 538 const NOISE_HCB:        u8 = 13;
 539 const INTENSITY_HCB2:   u8 = 14;
 540 const INTENSITY_HCB:    u8 = 15;
 541
 542 struct Codebooks {
 543     scale_cb:       Codebook<i8>,
 544     spec_cb:        [Codebook<u16>; 11],
 545 }
 546
 547 fn scale_map(idx: usize) -> i8 { (idx as i8) - 60 }
 548 fn cb_map(idx: usize) -> u16 { idx as u16 }
 549
 550 impl Codebooks {
 551     fn new() -> Self {
 552         let mut coderead = TableCodebookDescReader::new(AAC_SCF_CODEBOOK_CODES, AAC_SCF_CODEBOOK_BITS, scale_map);
 553         let scale_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 554         let mut spec_cb: [Codebook<u16>; 11];
 555         unsafe {
 556             spec_cb = mem::uninitialized();
 557             for i in 0..AAC_SPEC_CODES.len() {
 558                 let mut coderead = TableCodebookDescReader::new(AAC_SPEC_CODES[i], AAC_SPEC_BITS[i], cb_map);
 559                 ptr::write(&mut spec_cb[i], Codebook::new(&mut coderead, CodebookMode::MSB).unwrap());
 560             }
 561         }
 562         Self { scale_cb, spec_cb }
 563     }
 564 }
 565
 566 #[derive(Clone)]
 567 struct ICS {
 568     global_gain:    u8,
 569     info:           ICSInfo,
 570     pulse_data:     Option<PulseData>,
 571     tns_data:       Option<TNSData>,
 572     gain_control:   Option<GainControlData>,
 573     sect_cb:        [[u8; MAX_SFBS]; MAX_WINDOWS],
 574     sect_len:       [[usize; MAX_SFBS]; MAX_WINDOWS],
 575     sfb_cb:         [[u8; MAX_SFBS]; MAX_WINDOWS],
 576     num_sec:        [usize; MAX_WINDOWS],
 577     scales:         [[u8; MAX_SFBS]; MAX_WINDOWS],
 578     sbinfo:         GASubbandInfo,
 579     coeffs:         [f32; 1024],
 580     delay:          [f32; 1024],
 581 }
 582
 583 const INTENSITY_SCALE_MIN:  i16 = -155;
 584 const NOISE_SCALE_MIN:      i16 = -100;
 585 impl ICS {
 586     fn new(sbinfo: GASubbandInfo) -> Self {
 587         Self {
 588             global_gain:    0,
 589             info:           ICSInfo::new(),
 590             pulse_data:     None,
 591             tns_data:       None,
 592             gain_control:   None,
 593             sect_cb:        [[0; MAX_SFBS]; MAX_WINDOWS],
 594             sect_len:       [[0; MAX_SFBS]; MAX_WINDOWS],
 595             sfb_cb:         [[0; MAX_SFBS]; MAX_WINDOWS],
 596             scales:         [[0; MAX_SFBS]; MAX_WINDOWS],
 597             num_sec:        [0; MAX_WINDOWS],
 598             sbinfo,
 599             coeffs:         [0.0; 1024],
 600             delay:          [0.0; 1024],
 601         }
 602     }
 603     fn decode_section_data(&mut self, br: &mut BitReader, may_have_intensity: bool) -> DecoderResult<()> {
 604         let sect_bits = if self.info.long_win { 5 } else { 3 };
 605         let sect_esc_val = (1 << sect_bits) - 1;
 606
 607         for g in 0..self.info.window_groups {
 608             let mut k = 0;
 609             let mut l = 0;
 610             while k < self.info.max_sfb {
 611                 self.sect_cb[g][l]                      = br.read(4)? as u8;
 612                 self.sect_len[g][l] = 0;
 613                 validate!(self.sect_cb[g][l] != RESERVED_HCB);
 614                 if ((self.sect_cb[g][l] == INTENSITY_HCB) || (self.sect_cb[g][l] == INTENSITY_HCB2)) && !may_have_intensity {
 615                     return Err(DecoderError::InvalidData);
 616                 }
 617                 loop {
 618                     let sect_len_incr                   = br.read(sect_bits)? as usize;
 619                     self.sect_len[g][l] += sect_len_incr;
 620                     if sect_len_incr < sect_esc_val { break; }
 621                 }
 622                 validate!(k + self.sect_len[g][l] <= self.info.max_sfb);
 623                 for _ in 0..self.sect_len[g][l] {
 624                     self.sfb_cb[g][k] = self.sect_cb[g][l];
 625                     k += 1;
 626                 }
 627                 l += 1;
 628             }
 629             self.num_sec[g] = l;
 630         }
 631         Ok(())
 632     }
 633     fn is_intensity(&self, g: usize, sfb: usize) -> bool {
 634         (self.sfb_cb[g][sfb] == INTENSITY_HCB) || (self.sfb_cb[g][sfb] == INTENSITY_HCB2)
 635     }
 636     fn get_intensity_dir(&self, g: usize, sfb: usize) -> bool {
 637         self.sfb_cb[g][sfb] == INTENSITY_HCB
 638     }
 639     fn decode_scale_factor_data(&mut self, br: &mut BitReader, codebooks: &Codebooks) -> DecoderResult<()> {
 640         let mut noise_pcm_flag = true;
 641         let mut scf_normal = i16::from(self.global_gain);
 642         let mut scf_intensity = 0i16;
 643         let mut scf_noise  = 0i16;
 644         for g in 0..self.info.window_groups {
 645             for sfb in 0..self.info.max_sfb {
 646                 if self.sfb_cb[g][sfb] != ZERO_HCB {
 647                     if self.is_intensity(g, sfb) {
 648                         let diff                        = i16::from(br.read_cb(&codebooks.scale_cb)?);
 649                         scf_intensity += diff;
 650                         validate!((scf_intensity >= INTENSITY_SCALE_MIN) && (scf_intensity < INTENSITY_SCALE_MIN + 256));
 651                         self.scales[g][sfb] = (scf_intensity - INTENSITY_SCALE_MIN) as u8;
 652                     } else if self.sfb_cb[g][sfb] == NOISE_HCB {
 653                         if noise_pcm_flag {
 654                             noise_pcm_flag = false;
 655                             scf_noise                   = (br.read(9)? as i16) - 256 + i16::from(self.global_gain) - 90;
 656                         } else {
 657                             scf_noise                  += i16::from(br.read_cb(&codebooks.scale_cb)?);
 658                         }
 659                         validate!((scf_noise >= NOISE_SCALE_MIN) && (scf_noise < NOISE_SCALE_MIN + 256));
 660                         self.scales[g][sfb] = (scf_noise - NOISE_SCALE_MIN) as u8;
 661                     } else {
 662                         scf_normal                     += i16::from(br.read_cb(&codebooks.scale_cb)?);
 663                         validate!((scf_normal >= 0) && (scf_normal < 255));
 664                         self.scales[g][sfb] = scf_normal as u8;
 665                     }
 666                 }
 667             }
 668         }
 669         Ok(())
 670     }
 671     fn get_band_start(&self, swb: usize) -> usize {
 672         if self.info.long_win {
 673             self.sbinfo.long_bands[swb]
 674         } else {
 675             self.sbinfo.short_bands[swb]
 676         }
 677     }
 678     fn get_num_bands(&self) -> usize {
 679         if self.info.long_win {
 680             self.sbinfo.long_bands.len() - 1
 681         } else {
 682             self.sbinfo.short_bands.len() - 1
 683         }
 684     }
 685     fn decode_spectrum(&mut self, br: &mut BitReader, codebooks: &Codebooks) -> DecoderResult<()> {
 686         self.coeffs = [0.0; 1024];
 687         for g in 0..self.info.window_groups {
 688             let cur_w   = self.info.get_group_start(g);
 689             let next_w  = self.info.get_group_start(g + 1);
 690             for sfb in 0..self.info.max_sfb {
 691                 let start = self.get_band_start(sfb);
 692                 let end   = self.get_band_start(sfb + 1);
 693                 let cb_idx = self.sfb_cb[g][sfb];
 694                 for w in cur_w..next_w {
 695                     let dst = &mut self.coeffs[start + w*128..end + w*128];
 696                     match cb_idx {
 697                         ZERO_HCB => { /* zeroes */ },
 698                         NOISE_HCB => { /* noise */ },
 699                         INTENSITY_HCB | INTENSITY_HCB2 => { /* intensity */ },
 700                         _ => {
 701                                 let unsigned = AAC_UNSIGNED_CODEBOOK[(cb_idx - 1) as usize];
 702                                 let scale = get_scale(self.scales[g][sfb]);
 703                                 let cb = &codebooks.spec_cb[(cb_idx - 1) as usize];
 704                                 if cb_idx < FIRST_PAIR_HCB {
 705                                     decode_quads(br, cb, unsigned, scale, dst)?;
 706                                 } else {
 707                                     decode_pairs(br, cb, unsigned, cb_idx == ESC_HCB,
 708                                                  AAC_CODEBOOK_MODULO[(cb_idx - FIRST_PAIR_HCB) as usize], scale, dst)?;
 709                                 }
 710                             },
 711                     };
 712                 }
 713             }
 714         }
 715         Ok(())
 716     }
 717     fn place_pulses(&mut self) {
 718         if let Some(ref pdata) = self.pulse_data {
 719             if pdata.pulse_start_sfb >= self.sbinfo.long_bands.len() - 1 { return; }
 720             let mut k = self.get_band_start(pdata.pulse_start_sfb);
 721             let mut band = pdata.pulse_start_sfb;
 722             for pno in 0..pdata.number_pulse {
 723                 k += pdata.pulse_offset[pno] as usize;
 724                 if k >= 1024 { return; }
 725                 while self.get_band_start(band + 1) <= k { band += 1; }
 726                 let scale = get_scale(self.scales[0][band]);
 727                 let mut base = self.coeffs[k];
 728                 if base != 0.0 {
 729                     base = requant(self.coeffs[k], scale);
 730                 }
 731                 if base > 0.0 {
 732                     base += f32::from(pdata.pulse_amp[pno]);
 733                 } else {
 734                     base -= f32::from(pdata.pulse_amp[pno]);
 735                 }
 736                 self.coeffs[k] = iquant(base) * scale;
 737             }
 738         }
 739     }
 740     fn decode_ics(&mut self, br: &mut BitReader, codebooks: &Codebooks, m4atype: M4AType, common_window: bool, may_have_intensity: bool) -> DecoderResult<()> {
 741         self.global_gain                                = br.read(8)? as u8;
 742         if !common_window {
 743             self.info.decode_ics_info(br)?;
 744         }
 745         self.decode_section_data(br, may_have_intensity)?;
 746         self.decode_scale_factor_data(br, codebooks)?;
 747         self.pulse_data = PulseData::read(br)?;
 748         validate!(self.pulse_data.is_none() || self.info.long_win);
 749         let tns_max_order;
 750         if !self.info.long_win {
 751             tns_max_order = 7;
 752         } else if m4atype == M4AType::LC {
 753             tns_max_order = 12;
 754         } else {
 755             tns_max_order = TNS_MAX_ORDER;
 756         }
 757         self.tns_data = TNSData::read(br, self.info.long_win, self.info.num_windows, tns_max_order)?;
 758         if m4atype == M4AType::SSR {
 759             self.gain_control = GainControlData::read(br)?;
 760         } else {
 761             let gain_control_data_present               = br.read_bool()?;
 762             validate!(!gain_control_data_present);
 763         }
 764         self.decode_spectrum(br, codebooks)?;
 765         Ok(())
 766     }
 767     fn synth_channel(&mut self, dsp: &mut DSP, dst: &mut [f32], srate_idx: usize) {
 768         self.place_pulses();
 769         if let Some(ref tns_data) = self.tns_data {
 770             let tns_max_bands = (if self.info.long_win {
 771                     TNS_MAX_LONG_BANDS[srate_idx]
 772                 } else {
 773                     TNS_MAX_SHORT_BANDS[srate_idx]
 774                 }).min(self.info.max_sfb);
 775             for w in 0..self.info.num_windows {
 776                 let mut bottom = self.get_num_bands();
 777                 for f in 0..tns_data.n_filt[w] {
 778                     let top = bottom;
 779                     bottom = if top >= tns_data.coeffs[w][f].length { top - tns_data.coeffs[w][f].length } else { 0 };
 780                     let order = tns_data.coeffs[w][f].order;
 781                     if order == 0 { continue; }
 782                     let start = w * 128 + self.get_band_start(tns_max_bands.min(bottom));
 783                     let end   = w * 128 + self.get_band_start(tns_max_bands.min(top));
 784                     let lpc = &tns_data.coeffs[w][f].coef;
 785                     if !tns_data.coeffs[w][f].direction {
 786                         for m in start..end {
 787                             for i in 0..order.min(m) {
 788                                 self.coeffs[m] -= self.coeffs[m - i - 1] * lpc[i];
 789                             }
 790                         }
 791                     } else {
 792                         for m in (start..end).rev() {
 793                             for i in 0..order.min(m) {
 794                                 self.coeffs[m] -= self.coeffs[m + i - 1] * lpc[i];
 795                             }
 796                         }
 797                     }
 798                 }
 799             }
 800         }
 801         dsp.synth(&self.coeffs, &mut self.delay, self.info.window_sequence, self.info.window_shape, self.info.prev_window_shape, dst);
 802     }
 803 }
 804
 805 fn get_scale(scale: u8) -> f32 {
 806     2.0f32.powf(0.25 * (f32::from(scale) - 100.0 - 56.0))
 807 }
 808 fn iquant(val: f32) -> f32 {
 809     if val < 0.0 {
 810         -((-val).powf(4.0 / 3.0))
 811     } else {
 812         val.powf(4.0 / 3.0)
 813     }
 814 }
 815 fn requant(val: f32, scale: f32) -> f32 {
 816     if scale == 0.0 { return 0.0; }
 817     let bval = val / scale;
 818     if bval >= 0.0 {
 819         val.powf(3.0 / 4.0)
 820     } else {
 821         -((-val).powf(3.0 / 4.0))
 822     }
 823 }
 824 fn decode_quads(br: &mut BitReader, cb: &Codebook<u16>, unsigned: bool, scale: f32, dst: &mut [f32]) -> DecoderResult<()> {
 825     for out in dst.chunks_mut(4) {
 826         let cw                                          = br.read_cb(cb)? as usize;
 827         if unsigned {
 828             for i in 0..4 {
 829                 let val = AAC_QUADS[cw][i];
 830                 if val != 0 {
 831                     if br.read_bool()? {
 832                         out[i] = iquant(-f32::from(val)) * scale;
 833                     } else {
 834                         out[i] = iquant( f32::from(val)) * scale;
 835                     }
 836                 }
 837             }
 838         } else {
 839             for i in 0..4 {
 840                 out[i] = iquant(f32::from(AAC_QUADS[cw][i] - 1)) * scale;
 841             }
 842         }
 843     }
 844     Ok(())
 845 }
 846 fn decode_pairs(br: &mut BitReader, cb: &Codebook<u16>, unsigned: bool, escape: bool, modulo: u16, scale: f32, dst: &mut [f32]) -> DecoderResult<()> {
 847     for out in dst.chunks_mut(2) {
 848         let cw                                          = br.read_cb(cb)?;
 849         let mut x = (cw / modulo) as i16;
 850         let mut y = (cw % modulo) as i16;
 851         if unsigned {
 852             if x != 0 && br.read_bool()? {
 853                 x = -x;
 854             }
 855             if y != 0 && br.read_bool()? {
 856                 y = -y;
 857             }
 858         } else {
 859             x -= (modulo >> 1) as i16;
 860             y -= (modulo >> 1) as i16;
 861         }
 862         if escape {
 863             if (x == 16) || (x == -16) {
 864                 x += read_escape(br, x > 0)?;
 865             }
 866             if (y == 16) || (y == -16) {
 867                 y += read_escape(br, y > 0)?;
 868             }
 869         }
 870         out[0] = iquant(f32::from(x)) * scale;
 871         out[1] = iquant(f32::from(y)) * scale;
 872     }
 873     Ok(())
 874 }
 875 fn read_escape(br: &mut BitReader, sign: bool) -> DecoderResult<i16> {
 876     let prefix                                          = br.read_code(UintCodeType::UnaryOnes)? as u8;
 877     validate!(prefix < 9);
 878     let bits                                            = br.read(prefix + 4)? as i16;
 879     if sign {
 880         Ok(bits)
 881     } else {
 882         Ok(-bits)
 883     }
 884 }
 885
 886 #[derive(Clone)]
 887 struct ChannelPair {
 888     pair:               bool,
 889     channel:            usize,
 890     common_window:      bool,
 891     ms_mask_present:    u8,
 892     ms_used:            [[bool; MAX_SFBS]; MAX_WINDOWS],
 893     ics:                [ICS; 2],
 894 }
 895
 896 impl ChannelPair {
 897     fn new(pair: bool, channel: usize, sbinfo: GASubbandInfo) -> Self {
 898         Self {
 899             pair, channel,
 900             common_window:      false,
 901             ms_mask_present:    0,
 902             ms_used:            [[false; MAX_SFBS]; MAX_WINDOWS],
 903             ics:                [ICS::new(sbinfo), ICS::new(sbinfo)],
 904         }
 905     }
 906     fn decode_ga_sce(&mut self, br: &mut BitReader, codebooks: &Codebooks, m4atype: M4AType) -> DecoderResult<()> {
 907         self.ics[0].decode_ics(br, codebooks, m4atype, false, false)?;
 908         Ok(())
 909     }
 910     fn decode_ga_cpe(&mut self, br: &mut BitReader, codebooks: &Codebooks, m4atype: M4AType) -> DecoderResult<()> {
 911         let common_window                               = br.read_bool()?;
 912         self.common_window = common_window;
 913         if common_window {
 914             self.ics[0].info.decode_ics_info(br)?;
 915             self.ms_mask_present                        = br.read(2)? as u8;
 916             validate!(self.ms_mask_present != 3);
 917             if self.ms_mask_present == 1 {
 918                 for g in 0..self.ics[0].info.window_groups {
 919                     for sfb in 0..self.ics[0].info.max_sfb {
 920                         self.ms_used[g][sfb]            = br.read_bool()?;
 921                     }
 922                 }
 923             }
 924             self.ics[1].info = self.ics[0].info;
 925         }
 926         self.ics[0].decode_ics(br, codebooks, m4atype, common_window, true)?;
 927         self.ics[1].decode_ics(br, codebooks, m4atype, common_window, false)?;
 928         if common_window && self.ms_mask_present != 0 {
 929             let mut g = 0;
 930             for w in 0..self.ics[0].info.num_windows {
 931                 if w > 0 && self.ics[0].info.scale_factor_grouping[w - 1] {
 932                     g += 1;
 933                 }
 934                 for sfb in 0..self.ics[0].info.max_sfb {
 935                     let start = w * 128 + self.ics[0].get_band_start(sfb);
 936                     let end   = w * 128 + self.ics[0].get_band_start(sfb + 1);
 937                     if self.ics[0].is_intensity(g, sfb) {
 938                         let invert = (self.ms_mask_present == 1) && self.ms_used[g][sfb];
 939                         let dir = self.ics[0].get_intensity_dir(g, sfb) ^ invert;
 940                         let scale = 0.5f32.powf(0.25 * (f32::from(self.ics[0].scales[g][sfb]) + f32::from(INTENSITY_SCALE_MIN)));
 941                         if !dir {
 942                             for i in start..end {
 943                                 self.ics[1].coeffs[i] = scale * self.ics[0].coeffs[i];
 944                             }
 945                         } else {
 946                             for i in start..end {
 947                                 self.ics[1].coeffs[i] = -scale * self.ics[0].coeffs[i];
 948                             }
 949                         }
 950                     } else if (self.ms_mask_present == 2) || self.ms_used[g][sfb] {
 951                         for i in start..end {
 952                             let tmp = self.ics[0].coeffs[i] - self.ics[1].coeffs[i];
 953                             self.ics[0].coeffs[i] += self.ics[1].coeffs[i];
 954                             self.ics[1].coeffs[i] = tmp;
 955                         }
 956                     }
 957                 }
 958             }
 959         }
 960         Ok(())
 961     }
 962     fn synth_audio(&mut self, dsp: &mut DSP, abuf: &mut NABufferType, srate_idx: usize) {
 963         let mut adata = abuf.get_abuf_f32().unwrap();
 964         let output = adata.get_data_mut().unwrap();
 965         let off0 = abuf.get_offset(self.channel);
 966         let off1 = abuf.get_offset(self.channel + 1);
 967         self.ics[0].synth_channel(dsp, &mut output[off0..], srate_idx);
 968         if self.pair {
 969             self.ics[1].synth_channel(dsp, &mut output[off1..], srate_idx);
 970         }
 971     }
 972 }
 973
 974 struct DSP {
 975     kbd_long_win:   [f32; 1024],
 976     kbd_short_win:  [f32; 128],
 977     sine_long_win:  [f32; 1024],
 978     sine_short_win: [f32; 128],
 979     imdct_long:     IMDCT,
 980     imdct_short:    IMDCT,
 981     tmp:            [f32; 2048],
 982     ew_buf:         [f32; 1152],
 983 }
 984
 985 const SHORT_WIN_POINT0: usize = 512 - 64;
 986 const SHORT_WIN_POINT1: usize = 512 + 64;
 987
 988 impl DSP {
 989     fn new() -> Self {
 990         let mut kbd_long_win: [f32; 1024] = [0.0; 1024];
 991         let mut kbd_short_win: [f32; 128] = [0.0; 128];
 992         generate_window(WindowType::KaiserBessel(4.0), 1.0, 1024, true, &mut kbd_long_win);
 993         generate_window(WindowType::KaiserBessel(6.0), 1.0,  128, true, &mut kbd_short_win);
 994         let mut sine_long_win: [f32; 1024] = [0.0; 1024];
 995         let mut sine_short_win: [f32; 128] = [0.0; 128];
 996         generate_window(WindowType::Sine, 1.0, 1024, true, &mut sine_long_win);
 997         generate_window(WindowType::Sine, 1.0,  128, true, &mut sine_short_win);
 998         Self {
 999             kbd_long_win, kbd_short_win,
1000             sine_long_win, sine_short_win,
1001             imdct_long: IMDCT::new(1024 * 2, true),
1002             imdct_short: IMDCT::new(128 * 2, true),
1003             tmp: [0.0; 2048], ew_buf: [0.0; 1152],
1004         }
1005     }
1006     fn synth(&mut self, coeffs: &[f32; 1024], delay: &mut [f32; 1024], seq: u8, window_shape: bool, prev_window_shape: bool, dst: &mut [f32]) {
1007         let long_win  = if window_shape { &self.kbd_long_win  } else { &self.sine_long_win };
1008         let short_win = if window_shape { &self.kbd_short_win } else { &self.sine_short_win };
1009         let left_long_win  = if prev_window_shape { &self.kbd_long_win  } else { &self.sine_long_win };
1010         let left_short_win = if prev_window_shape { &self.kbd_short_win } else { &self.sine_short_win };
1011         if seq != EIGHT_SHORT_SEQUENCE {
1012             self.imdct_long.imdct(coeffs, &mut self.tmp);
1013         } else {
1014             for (ain, aout) in coeffs.chunks(128).zip(self.tmp.chunks_mut(256)) {
1015                 self.imdct_short.imdct(ain, aout);
1016             }
1017             self.ew_buf = [0.0; 1152];
1018             for (w, src) in self.tmp.chunks(256).enumerate() {
1019                 if w > 0 {
1020                     for i in 0..128 {
1021                         self.ew_buf[w * 128 + i] += src[i] * short_win[i];
1022                     }
1023                 } else { // to be left-windowed
1024                     for i in 0..128 {
1025                         self.ew_buf[i] = src[i];
1026                     }
1027                 }
1028                 for i in 0..128 {
1029                     self.ew_buf[w * 128 + i + 128] += src[i + 128] * short_win[127 - i];
1030                 }
1031             }
1032         }
1033         if seq == ONLY_LONG_SEQUENCE { // should be the most common case
1034             for i in 0..1024 {
1035                 dst[i] = delay[i] + self.tmp[i] * left_long_win[i];
1036                 delay[i] = self.tmp[i + 1024] * long_win[1023 - i];
1037             }
1038             return;
1039         }
1040         // output new data
1041         match seq {
1042             ONLY_LONG_SEQUENCE | LONG_START_SEQUENCE => {
1043                     for i in 0..1024 {
1044                         dst[i] = self.tmp[i] * left_long_win[i] + delay[i];
1045                     }
1046                 },
1047             EIGHT_SHORT_SEQUENCE => {
1048                     for i in 0..SHORT_WIN_POINT0 {
1049                         dst[i] = delay[i];
1050                     }
1051                     for i in SHORT_WIN_POINT0..SHORT_WIN_POINT1 {
1052                         let j = i - SHORT_WIN_POINT0;
1053                         dst[i] = delay[i] + self.ew_buf[j] * left_short_win[j];
1054                     }
1055                     for i in SHORT_WIN_POINT1..1024 {
1056                         let j = i - SHORT_WIN_POINT0;
1057                         dst[i] = self.ew_buf[j];
1058                     }
1059                 },
1060             LONG_STOP_SEQUENCE => {
1061                     for i in 0..SHORT_WIN_POINT0 {
1062                         dst[i] = delay[i];
1063                     }
1064                     for i in SHORT_WIN_POINT0..SHORT_WIN_POINT1 {
1065                         dst[i] = delay[i] + self.tmp[i] * left_short_win[i - SHORT_WIN_POINT0];
1066                     }
1067                     for i in SHORT_WIN_POINT1..1024 {
1068                         dst[i] = self.tmp[i];
1069                     }
1070                 },
1071             _ => unreachable!(""),
1072         };
1073         // save delay
1074         match seq {
1075             ONLY_LONG_SEQUENCE | LONG_STOP_SEQUENCE => {
1076                     for i in 0..1024 {
1077                         delay[i] = self.tmp[i + 1024] * long_win[1023 - i];
1078                     }
1079                 },
1080             EIGHT_SHORT_SEQUENCE => {
1081                     for i in 0..SHORT_WIN_POINT1 { // last part is already windowed
1082                         delay[i] = self.ew_buf[i + 512+64];
1083                     }
1084                     for i in SHORT_WIN_POINT1..1024 {
1085                         delay[i] = 0.0;
1086                     }
1087                 },
1088             LONG_START_SEQUENCE   => {
1089                     for i in 0..SHORT_WIN_POINT0 {
1090                         delay[i] = self.tmp[i + 1024];
1091                     }
1092                     for i in SHORT_WIN_POINT0..SHORT_WIN_POINT1 {
1093                         delay[i] = self.tmp[i + 1024] * short_win[127 - (i - SHORT_WIN_POINT0)];
1094                     }
1095                     for i in SHORT_WIN_POINT1..1024 {
1096                         delay[i] = 0.0;
1097                     }
1098                 },
1099             _ => unreachable!(""),
1100         };
1101     }
1102 }
1103
1104 struct AACDecoder {
1105     info:       NACodecInfoRef,
1106     chmap:      NAChannelMap,
1107     m4ainfo:    M4AInfo,
1108     pairs:      Vec<ChannelPair>,
1109     codebooks:  Codebooks,
1110     dsp:        DSP,
1111     sbinfo:     GASubbandInfo,
1112 }
1113
1114 impl AACDecoder {
1115     fn new() -> Self {
1116         AACDecoder {
1117             info:       NACodecInfo::new_dummy(),
1118             chmap:      NAChannelMap::new(),
1119             m4ainfo:    M4AInfo::new(),
1120             pairs:      Vec::new(),
1121             codebooks:  Codebooks::new(),
1122             dsp:        DSP::new(),
1123             sbinfo:     AAC_SUBBAND_INFO[0],
1124         }
1125     }
1126     fn set_pair(&mut self, pair_no: usize, channel: usize, pair: bool) -> DecoderResult<()> {
1127         if self.pairs.len() <= pair_no {
1128             self.pairs.push(ChannelPair::new(pair, channel, self.sbinfo));
1129         } else {
1130             validate!(self.pairs[pair_no].channel == channel);
1131             validate!(self.pairs[pair_no].pair    == pair);
1132         }
1133         validate!(if pair { channel + 1 } else { channel } < self.m4ainfo.channels);
1134         Ok(())
1135     }
1136     fn decode_ga(&mut self, br: &mut BitReader, abuf: &mut NABufferType) -> DecoderResult<()> {
1137         let mut cur_pair = 0;
1138         let mut cur_ch   = 0;
1139         while br.left() > 3 {
1140             let id                                      = br.read(3)?;
1141             match id {
1142                 0 => { // ID_SCE
1143                         let _tag                        = br.read(4)?;
1144                         self.set_pair(cur_pair, cur_ch, false)?;
1145                         self.pairs[cur_pair].decode_ga_sce(br, &self.codebooks, self.m4ainfo.otype)?;
1146                         cur_pair += 1;
1147                         cur_ch   += 1;
1148                     },
1149                 1 => { // ID_CPE
1150                         let _tag                        = br.read(4)?;
1151                         self.set_pair(cur_pair, cur_ch, true)?;
1152                         self.pairs[cur_pair].decode_ga_cpe(br, &self.codebooks, self.m4ainfo.otype)?;
1153                         cur_pair += 1;
1154                         cur_ch   += 2;
1155                     },
1156                 2 => { // ID_CCE
1157                         unimplemented!("coupling channel element");
1158                     },
1159                 3 => { // ID_LFE
1160                         let _tag                        = br.read(4)?;
1161                         self.set_pair(cur_pair, cur_ch, false)?;
1162                         self.pairs[cur_pair].decode_ga_sce(br, &self.codebooks, self.m4ainfo.otype)?;
1163                         cur_pair += 1;
1164                         cur_ch   += 1;
1165                     },
1166                 4 => { // ID_DSE
1167                         let _id                         = br.read(4)?;
1168                         let align                       = br.read_bool()?;
1169                         let mut count                   = br.read(8)? as u32;
1170                         if count == 255 { count        += br.read(8)? as u32; }
1171                         if align {                        br.align(); }
1172                                                           br.skip(count * 8)?; // no SBR payload or such
1173                     },
1174                 5 => { // ID_PCE
1175                         unimplemented!("program config");
1176                     },
1177                 6 => { // ID_FIL
1178                         let mut count                   = br.read(4)? as usize;
1179                         if count == 15 {
1180                             count                      += br.read(8)? as usize;
1181                             count -= 1;
1182                         }
1183                         for _ in 0..count {
1184                             // ext payload
1185                                                           br.skip(8)?;
1186                         }
1187                     },
1188                 7 => { // ID_TERM
1189                         break;
1190                     },
1191                 _ => { unreachable!(); },
1192             };
1193         }
1194         let srate_idx = GASubbandInfo::find_idx(self.m4ainfo.srate);
1195         for pair in 0..cur_pair {
1196             self.pairs[pair].synth_audio(&mut self.dsp, abuf, srate_idx);
1197         }
1198         Ok(())
1199     }
1200 }
1201
1202 impl NADecoder for AACDecoder {
1203     fn init(&mut self, _supp: &mut NADecoderSupport, info: NACodecInfoRef) -> DecoderResult<()> {
1204         if let NACodecTypeInfo::Audio(_) = info.get_properties() {
1205             let edata = info.get_extradata().unwrap();
1206             validate!(edata.len() >= 2);
1207
1208 //print!("edata:"); for s in edata.iter() { print!(" {:02X}", *s);}println!("");
1209             self.m4ainfo.read(&edata)?;
1210
1211             //println!("{}", self.m4ainfo);
1212             if (self.m4ainfo.otype != M4AType::LC) || (self.m4ainfo.channels > 2) || (self.m4ainfo.samples != 1024) {
1213                 return Err(DecoderError::NotImplemented);
1214             }
1215             self.sbinfo = GASubbandInfo::find(self.m4ainfo.srate);
1216
1217             let ainfo = NAAudioInfo::new(self.m4ainfo.srate, self.m4ainfo.channels as u8,
1218                                          SND_F32P_FORMAT, self.m4ainfo.samples);
1219             self.info = info.replace_info(NACodecTypeInfo::Audio(ainfo));
1220
1221             if self.m4ainfo.channels >= DEFAULT_CHANNEL_MAP.len() {
1222                 return Err(DecoderError::NotImplemented);
1223             }
1224             let chmap_str = DEFAULT_CHANNEL_MAP[self.m4ainfo.channels];
1225             if chmap_str.is_empty() { return Err(DecoderError::NotImplemented); }
1226             self.chmap = NAChannelMap::from_str(chmap_str).unwrap();
1227
1228             Ok(())
1229         } else {
1230             Err(DecoderError::InvalidData)
1231         }
1232     }
1233     fn decode(&mut self, _supp: &mut NADecoderSupport, pkt: &NAPacket) -> DecoderResult<NAFrameRef> {
1234         let info = pkt.get_stream().get_info();
1235         validate!(info.get_properties().is_audio());
1236         let pktbuf = pkt.get_buffer();
1237
1238         let ainfo = self.info.get_properties().get_audio_info().unwrap();
1239         let mut abuf = alloc_audio_buffer(ainfo, self.m4ainfo.samples, self.chmap.clone())?;
1240
1241         let mut br = BitReader::new(&pktbuf, BitReaderMode::BE);
1242         match self.m4ainfo.otype {
1243             M4AType::LC => {
1244                     self.decode_ga(&mut br, &mut abuf)?;
1245                 },
1246             _ => { unimplemented!(""); }
1247         }
1248
1249         let mut frm = NAFrame::new_from_pkt(pkt, self.info.replace_info(NACodecTypeInfo::Audio(ainfo)), abuf);
1250         frm.set_keyframe(true);
1251         Ok(frm.into_ref())
1252     }
1253     fn flush(&mut self) {
1254         for pair in self.pairs.iter_mut() {
1255             pair.ics[0].delay = [0.0; 1024];
1256             pair.ics[1].delay = [0.0; 1024];
1257         }
1258     }
1259 }
1260
1261 pub fn get_decoder() -> Box<dyn NADecoder + Send> {
1262     Box::new(AACDecoder::new())
1263 }
1264
1265 #[cfg(test)]
1266 mod test {
1267     use nihav_core::codecs::RegisteredDecoders;
1268     use nihav_core::demuxers::RegisteredDemuxers;
1269     use nihav_codec_support::test::dec_video::test_decode_audio;
1270     use crate::generic_register_all_codecs;
1271     use nihav_realmedia::realmedia_register_all_demuxers;
1272     #[test]
1273     fn test_aac() {
1274         let mut dmx_reg = RegisteredDemuxers::new();
1275         realmedia_register_all_demuxers(&mut dmx_reg);
1276         let mut dec_reg = RegisteredDecoders::new();
1277         generic_register_all_codecs(&mut dec_reg);
1278
1279 //        let file = "assets/RV/rv40_weighted_mc.rmvb";
1280         let file = "assets/RV/rv40_weighted_mc_2.rmvb";
1281         test_decode_audio("realmedia", file, Some(12000), None/*Some("aac")*/, &dmx_reg, &dec_reg);
1282     }
1283 }
1284
1285 const AAC_SCF_CODEBOOK_BITS: &[u8] = &[
1286     18, 18, 18, 18, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
1287     19, 19, 19, 18, 19, 18, 17, 17, 16, 17, 16, 16, 16, 16, 15, 15,
1288     14, 14, 14, 14, 14, 14, 13, 13, 12, 12, 12, 11, 12, 11, 10, 10,
1289     10,  9,  9,  8,  8,  8,  7,  6,  6,  5,  4,  3,  1,  4,  4,  5,
1290      6,  6,  7,  7,  8,  8,  9,  9, 10, 10, 10, 11, 11, 11, 11, 12,
1291     12, 13, 13, 13, 14, 14, 16, 15, 16, 15, 18, 19, 19, 19, 19, 19,
1292     19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
1293     19, 19, 19, 19, 19, 19, 19, 19, 19
1294 ];
1295
1296 const AAC_SCF_CODEBOOK_CODES: &[u32] = &[
1297     0x3FFE8, 0x3FFE6, 0x3FFE7, 0x3FFE5, 0x7FFF5, 0x7FFF1, 0x7FFED, 0x7FFF6,
1298     0x7FFEE, 0x7FFEF, 0x7FFF0, 0x7FFFC, 0x7FFFD, 0x7FFFF, 0x7FFFE, 0x7FFF7,
1299     0x7FFF8, 0x7FFFB, 0x7FFF9, 0x3FFE4, 0x7FFFA, 0x3FFE3, 0x1FFEF, 0x1FFF0,
1300     0x0FFF5, 0x1FFEE, 0x0FFF2, 0x0FFF3, 0x0FFF4, 0x0FFF1, 0x07FF6, 0x07FF7,
1301     0x03FF9, 0x03FF5, 0x03FF7, 0x03FF3, 0x03FF6, 0x03FF2, 0x01FF7, 0x01FF5,
1302     0x00FF9, 0x00FF7, 0x00FF6, 0x007F9, 0x00FF4, 0x007F8, 0x003F9, 0x003F7,
1303     0x003F5, 0x001F8, 0x001F7, 0x000FA, 0x000F8, 0x000F6, 0x00079, 0x0003A,
1304     0x00038, 0x0001A, 0x0000B, 0x00004, 0x00000, 0x0000A, 0x0000C, 0x0001B,
1305     0x00039, 0x0003B, 0x00078, 0x0007A, 0x000F7, 0x000F9, 0x001F6, 0x001F9,
1306     0x003F4, 0x003F6, 0x003F8, 0x007F5, 0x007F4, 0x007F6, 0x007F7, 0x00FF5,
1307     0x00FF8, 0x01FF4, 0x01FF6, 0x01FF8, 0x03FF8, 0x03FF4, 0x0FFF0, 0x07FF4,
1308     0x0FFF6, 0x07FF5, 0x3FFE2, 0x7FFD9, 0x7FFDA, 0x7FFDB, 0x7FFDC, 0x7FFDD,
1309     0x7FFDE, 0x7FFD8, 0x7FFD2, 0x7FFD3, 0x7FFD4, 0x7FFD5, 0x7FFD6, 0x7FFF2,
1310     0x7FFDF, 0x7FFE7, 0x7FFE8, 0x7FFE9, 0x7FFEA, 0x7FFEB, 0x7FFE6, 0x7FFE0,
1311     0x7FFE1, 0x7FFE2, 0x7FFE3, 0x7FFE4, 0x7FFE5, 0x7FFD7, 0x7FFEC, 0x7FFF4,
1312     0x7FFF3
1313 ];
1314
1315 const AAC_SPEC_CB1_BITS: &[u8] = &[
1316     11,  9, 11, 10,  7, 10, 11,  9, 11, 10,  7, 10,  7,  5,  7,  9,
1317      7, 10, 11,  9, 11,  9,  7,  9, 11,  9, 11,  9,  7,  9,  7,  5,
1318      7,  9,  7,  9,  7,  5,  7,  5,  1,  5,  7,  5,  7,  9,  7,  9,
1319      7,  5,  7,  9,  7,  9, 11,  9, 11,  9,  7,  9, 11,  9, 11, 10,
1320      7,  9,  7,  5,  7,  9,  7, 10, 11,  9, 11, 10,  7,  9, 11,  9,
1321     11
1322 ];
1323 const AAC_SPEC_CB1_CODES: &[u16] = &[
1324     0x7f8, 0x1f1, 0x7fd, 0x3f5, 0x068, 0x3f0, 0x7f7, 0x1ec,
1325     0x7f5, 0x3f1, 0x072, 0x3f4, 0x074, 0x011, 0x076, 0x1eb,
1326     0x06c, 0x3f6, 0x7fc, 0x1e1, 0x7f1, 0x1f0, 0x061, 0x1f6,
1327     0x7f2, 0x1ea, 0x7fb, 0x1f2, 0x069, 0x1ed, 0x077, 0x017,
1328     0x06f, 0x1e6, 0x064, 0x1e5, 0x067, 0x015, 0x062, 0x012,
1329     0x000, 0x014, 0x065, 0x016, 0x06d, 0x1e9, 0x063, 0x1e4,
1330     0x06b, 0x013, 0x071, 0x1e3, 0x070, 0x1f3, 0x7fe, 0x1e7,
1331     0x7f3, 0x1ef, 0x060, 0x1ee, 0x7f0, 0x1e2, 0x7fa, 0x3f3,
1332     0x06a, 0x1e8, 0x075, 0x010, 0x073, 0x1f4, 0x06e, 0x3f7,
1333     0x7f6, 0x1e0, 0x7f9, 0x3f2, 0x066, 0x1f5, 0x7ff, 0x1f7,
1334     0x7f4
1335 ];
1336 const AAC_SPEC_CB2_BITS: &[u8] = &[
1337     9, 7, 9, 8, 6, 8, 9, 8, 9, 8, 6, 7, 6, 5, 6, 7,
1338     6, 8, 9, 7, 8, 8, 6, 8, 9, 7, 9, 8, 6, 7, 6, 5,
1339     6, 7, 6, 8, 6, 5, 6, 5, 3, 5, 6, 5, 6, 8, 6, 7,
1340     6, 5, 6, 8, 6, 8, 9, 7, 9, 8, 6, 8, 8, 7, 9, 8,
1341     6, 7, 6, 4, 6, 8, 6, 7, 9, 7, 9, 7, 6, 8, 9, 7,
1342     9
1343 ];
1344 const AAC_SPEC_CB2_CODES: &[u16] = &[
1345     0x1f3, 0x06f, 0x1fd, 0x0eb, 0x023, 0x0ea, 0x1f7, 0x0e8,
1346     0x1fa, 0x0f2, 0x02d, 0x070, 0x020, 0x006, 0x02b, 0x06e,
1347     0x028, 0x0e9, 0x1f9, 0x066, 0x0f8, 0x0e7, 0x01b, 0x0f1,
1348     0x1f4, 0x06b, 0x1f5, 0x0ec, 0x02a, 0x06c, 0x02c, 0x00a,
1349     0x027, 0x067, 0x01a, 0x0f5, 0x024, 0x008, 0x01f, 0x009,
1350     0x000, 0x007, 0x01d, 0x00b, 0x030, 0x0ef, 0x01c, 0x064,
1351     0x01e, 0x00c, 0x029, 0x0f3, 0x02f, 0x0f0, 0x1fc, 0x071,
1352     0x1f2, 0x0f4, 0x021, 0x0e6, 0x0f7, 0x068, 0x1f8, 0x0ee,
1353     0x022, 0x065, 0x031, 0x002, 0x026, 0x0ed, 0x025, 0x06a,
1354     0x1fb, 0x072, 0x1fe, 0x069, 0x02e, 0x0f6, 0x1ff, 0x06d,
1355     0x1f6
1356 ];
1357 const AAC_SPEC_CB3_BITS: &[u8] = &[
1358      1,  4,  8,  4,  5,  8,  9,  9, 10,  4,  6,  9,  6,  6,  9,  9,
1359      9, 10,  9, 10, 13,  9,  9, 11, 11, 10, 12,  4,  6, 10,  6,  7,
1360     10, 10, 10, 12,  5,  7, 11,  6,  7, 10,  9,  9, 11,  9, 10, 13,
1361      8,  9, 12, 10, 11, 12,  8, 10, 15,  9, 11, 15, 13, 14, 16,  8,
1362     10, 14,  9, 10, 14, 12, 12, 15, 11, 12, 16, 10, 11, 15, 12, 12,
1363     15
1364 ];
1365 const AAC_SPEC_CB3_CODES: &[u16] = &[
1366     0x0000, 0x0009, 0x00ef, 0x000b, 0x0019, 0x00f0, 0x01eb, 0x01e6,
1367     0x03f2, 0x000a, 0x0035, 0x01ef, 0x0034, 0x0037, 0x01e9, 0x01ed,
1368     0x01e7, 0x03f3, 0x01ee, 0x03ed, 0x1ffa, 0x01ec, 0x01f2, 0x07f9,
1369     0x07f8, 0x03f8, 0x0ff8, 0x0008, 0x0038, 0x03f6, 0x0036, 0x0075,
1370     0x03f1, 0x03eb, 0x03ec, 0x0ff4, 0x0018, 0x0076, 0x07f4, 0x0039,
1371     0x0074, 0x03ef, 0x01f3, 0x01f4, 0x07f6, 0x01e8, 0x03ea, 0x1ffc,
1372     0x00f2, 0x01f1, 0x0ffb, 0x03f5, 0x07f3, 0x0ffc, 0x00ee, 0x03f7,
1373     0x7ffe, 0x01f0, 0x07f5, 0x7ffd, 0x1ffb, 0x3ffa, 0xffff, 0x00f1,
1374     0x03f0, 0x3ffc, 0x01ea, 0x03ee, 0x3ffb, 0x0ff6, 0x0ffa, 0x7ffc,
1375     0x07f2, 0x0ff5, 0xfffe, 0x03f4, 0x07f7, 0x7ffb, 0x0ff7, 0x0ff9,
1376     0x7ffa
1377 ];
1378 const AAC_SPEC_CB4_BITS: &[u8] = &[
1379      4,  5,  8,  5,  4,  8,  9,  8, 11,  5,  5,  8,  5,  4,  8,  8,
1380      7, 10,  9,  8, 11,  8,  8, 10, 11, 10, 11,  4,  5,  8,  4,  4,
1381      8,  8,  8, 10,  4,  4,  8,  4,  4,  7,  8,  7,  9,  8,  8, 10,
1382      7,  7,  9, 10,  9, 10,  8,  8, 11,  8,  7, 10, 11, 10, 12,  8,
1383      7, 10,  7,  7,  9, 10,  9, 11, 11, 10, 12, 10,  9, 11, 11, 10,
1384     11
1385 ];
1386 const AAC_SPEC_CB4_CODES: &[u16] = &[
1387     0x007, 0x016, 0x0f6, 0x018, 0x008, 0x0ef, 0x1ef, 0x0f3,
1388     0x7f8, 0x019, 0x017, 0x0ed, 0x015, 0x001, 0x0e2, 0x0f0,
1389     0x070, 0x3f0, 0x1ee, 0x0f1, 0x7fa, 0x0ee, 0x0e4, 0x3f2,
1390     0x7f6, 0x3ef, 0x7fd, 0x005, 0x014, 0x0f2, 0x009, 0x004,
1391     0x0e5, 0x0f4, 0x0e8, 0x3f4, 0x006, 0x002, 0x0e7, 0x003,
1392     0x000, 0x06b, 0x0e3, 0x069, 0x1f3, 0x0eb, 0x0e6, 0x3f6,
1393     0x06e, 0x06a, 0x1f4, 0x3ec, 0x1f0, 0x3f9, 0x0f5, 0x0ec,
1394     0x7fb, 0x0ea, 0x06f, 0x3f7, 0x7f9, 0x3f3, 0xfff, 0x0e9,
1395     0x06d, 0x3f8, 0x06c, 0x068, 0x1f5, 0x3ee, 0x1f2, 0x7f4,
1396     0x7f7, 0x3f1, 0xffe, 0x3ed, 0x1f1, 0x7f5, 0x7fe, 0x3f5,
1397     0x7fc
1398 ];
1399 const AAC_SPEC_CB5_BITS: &[u8] = &[
1400     13, 12, 11, 11, 10, 11, 11, 12, 13, 12, 11, 10,  9,  8,  9, 10,
1401     11, 12, 12, 10,  9,  8,  7,  8,  9, 10, 11, 11,  9,  8,  5,  4,
1402      5,  8,  9, 11, 10,  8,  7,  4,  1,  4,  7,  8, 11, 11,  9,  8,
1403      5,  4,  5,  8,  9, 11, 11, 10,  9,  8,  7,  8,  9, 10, 11, 12,
1404     11, 10,  9,  8,  9, 10, 11, 12, 13, 12, 12, 11, 10, 10, 11, 12,
1405     13
1406 ];
1407 const AAC_SPEC_CB5_CODES: &[u16] = &[
1408     0x1fff, 0x0ff7, 0x07f4, 0x07e8, 0x03f1, 0x07ee, 0x07f9, 0x0ff8,
1409     0x1ffd, 0x0ffd, 0x07f1, 0x03e8, 0x01e8, 0x00f0, 0x01ec, 0x03ee,
1410     0x07f2, 0x0ffa, 0x0ff4, 0x03ef, 0x01f2, 0x00e8, 0x0070, 0x00ec,
1411     0x01f0, 0x03ea, 0x07f3, 0x07eb, 0x01eb, 0x00ea, 0x001a, 0x0008,
1412     0x0019, 0x00ee, 0x01ef, 0x07ed, 0x03f0, 0x00f2, 0x0073, 0x000b,
1413     0x0000, 0x000a, 0x0071, 0x00f3, 0x07e9, 0x07ef, 0x01ee, 0x00ef,
1414     0x0018, 0x0009, 0x001b, 0x00eb, 0x01e9, 0x07ec, 0x07f6, 0x03eb,
1415     0x01f3, 0x00ed, 0x0072, 0x00e9, 0x01f1, 0x03ed, 0x07f7, 0x0ff6,
1416     0x07f0, 0x03e9, 0x01ed, 0x00f1, 0x01ea, 0x03ec, 0x07f8, 0x0ff9,
1417     0x1ffc, 0x0ffc, 0x0ff5, 0x07ea, 0x03f3, 0x03f2, 0x07f5, 0x0ffb,
1418     0x1ffe
1419 ];
1420 const AAC_SPEC_CB6_BITS: &[u8] = &[
1421     11, 10,  9,  9,  9,  9,  9, 10, 11, 10,  9,  8,  7,  7,  7,  8,
1422      9, 10,  9,  8,  6,  6,  6,  6,  6,  8,  9,  9,  7,  6,  4,  4,
1423      4,  6,  7,  9,  9,  7,  6,  4,  4,  4,  6,  7,  9,  9,  7,  6,
1424      4,  4,  4,  6,  7,  9,  9,  8,  6,  6,  6,  6,  6,  8,  9, 10,
1425      9,  8,  7,  7,  7,  7,  8, 10, 11, 10,  9,  9,  9,  9,  9, 10,
1426     11
1427 ];
1428 const AAC_SPEC_CB6_CODES: &[u16] = &[
1429     0x7fe, 0x3fd, 0x1f1, 0x1eb, 0x1f4, 0x1ea, 0x1f0, 0x3fc,
1430     0x7fd, 0x3f6, 0x1e5, 0x0ea, 0x06c, 0x071, 0x068, 0x0f0,
1431     0x1e6, 0x3f7, 0x1f3, 0x0ef, 0x032, 0x027, 0x028, 0x026,
1432     0x031, 0x0eb, 0x1f7, 0x1e8, 0x06f, 0x02e, 0x008, 0x004,
1433     0x006, 0x029, 0x06b, 0x1ee, 0x1ef, 0x072, 0x02d, 0x002,
1434     0x000, 0x003, 0x02f, 0x073, 0x1fa, 0x1e7, 0x06e, 0x02b,
1435     0x007, 0x001, 0x005, 0x02c, 0x06d, 0x1ec, 0x1f9, 0x0ee,
1436     0x030, 0x024, 0x02a, 0x025, 0x033, 0x0ec, 0x1f2, 0x3f8,
1437     0x1e4, 0x0ed, 0x06a, 0x070, 0x069, 0x074, 0x0f1, 0x3fa,
1438     0x7ff, 0x3f9, 0x1f6, 0x1ed, 0x1f8, 0x1e9, 0x1f5, 0x3fb,
1439     0x7fc
1440 ];
1441 const AAC_SPEC_CB7_BITS: &[u8] = &[
1442      1,  3,  6,  7,  8,  9, 10, 11,  3,  4,  6,  7,  8,  8,  9,  9,
1443      6,  6,  7,  8,  8,  9,  9, 10,  7,  7,  8,  8,  9,  9, 10, 10,
1444      8,  8,  9,  9, 10, 10, 10, 11,  9,  8,  9,  9, 10, 10, 11, 11,
1445     10,  9,  9, 10, 10, 11, 12, 12, 11, 10, 10, 10, 11, 11, 12, 12
1446 ];
1447 const AAC_SPEC_CB7_CODES: &[u16] = &[
1448     0x000, 0x005, 0x037, 0x074, 0x0f2, 0x1eb, 0x3ed, 0x7f7,
1449     0x004, 0x00c, 0x035, 0x071, 0x0ec, 0x0ee, 0x1ee, 0x1f5,
1450     0x036, 0x034, 0x072, 0x0ea, 0x0f1, 0x1e9, 0x1f3, 0x3f5,
1451     0x073, 0x070, 0x0eb, 0x0f0, 0x1f1, 0x1f0, 0x3ec, 0x3fa,
1452     0x0f3, 0x0ed, 0x1e8, 0x1ef, 0x3ef, 0x3f1, 0x3f9, 0x7fb,
1453     0x1ed, 0x0ef, 0x1ea, 0x1f2, 0x3f3, 0x3f8, 0x7f9, 0x7fc,
1454     0x3ee, 0x1ec, 0x1f4, 0x3f4, 0x3f7, 0x7f8, 0xffd, 0xffe,
1455     0x7f6, 0x3f0, 0x3f2, 0x3f6, 0x7fa, 0x7fd, 0xffc, 0xfff
1456 ];
1457 const AAC_SPEC_CB8_BITS: &[u8] = &[
1458      5,  4,  5,  6,  7,  8,  9, 10,  4,  3,  4,  5,  6,  7,  7,  8,
1459      5,  4,  4,  5,  6,  7,  7,  8,  6,  5,  5,  6,  6,  7,  8,  8,
1460      7,  6,  6,  6,  7,  7,  8,  9,  8,  7,  6,  7,  7,  8,  8, 10,
1461      9,  7,  7,  8,  8,  8,  9,  9, 10,  8,  8,  8,  9,  9,  9, 10
1462 ];
1463 const AAC_SPEC_CB8_CODES: &[u16] = &[
1464     0x00e, 0x005, 0x010, 0x030, 0x06f, 0x0f1, 0x1fa, 0x3fe,
1465     0x003, 0x000, 0x004, 0x012, 0x02c, 0x06a, 0x075, 0x0f8,
1466     0x00f, 0x002, 0x006, 0x014, 0x02e, 0x069, 0x072, 0x0f5,
1467     0x02f, 0x011, 0x013, 0x02a, 0x032, 0x06c, 0x0ec, 0x0fa,
1468     0x071, 0x02b, 0x02d, 0x031, 0x06d, 0x070, 0x0f2, 0x1f9,
1469     0x0ef, 0x068, 0x033, 0x06b, 0x06e, 0x0ee, 0x0f9, 0x3fc,
1470     0x1f8, 0x074, 0x073, 0x0ed, 0x0f0, 0x0f6, 0x1f6, 0x1fd,
1471     0x3fd, 0x0f3, 0x0f4, 0x0f7, 0x1f7, 0x1fb, 0x1fc, 0x3ff
1472 ];
1473 const AAC_SPEC_CB9_BITS: &[u8] = &[
1474      1,  3,  6,  8,  9, 10, 10, 11, 11, 12, 12, 13, 13,  3,  4,  6,
1475      7,  8,  8,  9, 10, 10, 10, 11, 12, 12,  6,  6,  7,  8,  8,  9,
1476     10, 10, 10, 11, 12, 12, 12,  8,  7,  8,  9,  9, 10, 10, 11, 11,
1477     11, 12, 12, 13,  9,  8,  9,  9, 10, 10, 11, 11, 11, 12, 12, 12,
1478     13, 10,  9,  9, 10, 11, 11, 11, 12, 11, 12, 12, 13, 13, 11,  9,
1479     10, 11, 11, 11, 12, 12, 12, 12, 13, 13, 13, 11, 10, 10, 11, 11,
1480     12, 12, 13, 13, 13, 13, 13, 13, 11, 10, 10, 11, 11, 11, 12, 12,
1481     13, 13, 14, 13, 14, 11, 10, 11, 11, 12, 12, 12, 12, 13, 13, 14,
1482     14, 14, 12, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 12,
1483     11, 12, 12, 12, 13, 13, 13, 13, 14, 14, 15, 15, 13, 12, 12, 12,
1484     13, 13, 13, 13, 14, 14, 14, 14, 15
1485 ];
1486 const AAC_SPEC_CB9_CODES: &[u16] = &[
1487     0x0000, 0x0005, 0x0037, 0x00e7, 0x01de, 0x03ce, 0x03d9, 0x07c8,
1488     0x07cd, 0x0fc8, 0x0fdd, 0x1fe4, 0x1fec, 0x0004, 0x000c, 0x0035,
1489     0x0072, 0x00ea, 0x00ed, 0x01e2, 0x03d1, 0x03d3, 0x03e0, 0x07d8,
1490     0x0fcf, 0x0fd5, 0x0036, 0x0034, 0x0071, 0x00e8, 0x00ec, 0x01e1,
1491     0x03cf, 0x03dd, 0x03db, 0x07d0, 0x0fc7, 0x0fd4, 0x0fe4, 0x00e6,
1492     0x0070, 0x00e9, 0x01dd, 0x01e3, 0x03d2, 0x03dc, 0x07cc, 0x07ca,
1493     0x07de, 0x0fd8, 0x0fea, 0x1fdb, 0x01df, 0x00eb, 0x01dc, 0x01e6,
1494     0x03d5, 0x03de, 0x07cb, 0x07dd, 0x07dc, 0x0fcd, 0x0fe2, 0x0fe7,
1495     0x1fe1, 0x03d0, 0x01e0, 0x01e4, 0x03d6, 0x07c5, 0x07d1, 0x07db,
1496     0x0fd2, 0x07e0, 0x0fd9, 0x0feb, 0x1fe3, 0x1fe9, 0x07c4, 0x01e5,
1497     0x03d7, 0x07c6, 0x07cf, 0x07da, 0x0fcb, 0x0fda, 0x0fe3, 0x0fe9,
1498     0x1fe6, 0x1ff3, 0x1ff7, 0x07d3, 0x03d8, 0x03e1, 0x07d4, 0x07d9,
1499     0x0fd3, 0x0fde, 0x1fdd, 0x1fd9, 0x1fe2, 0x1fea, 0x1ff1, 0x1ff6,
1500     0x07d2, 0x03d4, 0x03da, 0x07c7, 0x07d7, 0x07e2, 0x0fce, 0x0fdb,
1501     0x1fd8, 0x1fee, 0x3ff0, 0x1ff4, 0x3ff2, 0x07e1, 0x03df, 0x07c9,
1502     0x07d6, 0x0fca, 0x0fd0, 0x0fe5, 0x0fe6, 0x1feb, 0x1fef, 0x3ff3,
1503     0x3ff4, 0x3ff5, 0x0fe0, 0x07ce, 0x07d5, 0x0fc6, 0x0fd1, 0x0fe1,
1504     0x1fe0, 0x1fe8, 0x1ff0, 0x3ff1, 0x3ff8, 0x3ff6, 0x7ffc, 0x0fe8,
1505     0x07df, 0x0fc9, 0x0fd7, 0x0fdc, 0x1fdc, 0x1fdf, 0x1fed, 0x1ff5,
1506     0x3ff9, 0x3ffb, 0x7ffd, 0x7ffe, 0x1fe7, 0x0fcc, 0x0fd6, 0x0fdf,
1507     0x1fde, 0x1fda, 0x1fe5, 0x1ff2, 0x3ffa, 0x3ff7, 0x3ffc, 0x3ffd,
1508     0x7fff
1509 ];
1510 const AAC_SPEC_CB10_BITS: &[u8] = &[
1511      6,  5,  6,  6,  7,  8,  9, 10, 10, 10, 11, 11, 12,  5,  4,  4,
1512      5,  6,  7,  7,  8,  8,  9, 10, 10, 11,  6,  4,  5,  5,  6,  6,
1513      7,  8,  8,  9,  9, 10, 10,  6,  5,  5,  5,  6,  7,  7,  8,  8,
1514      9,  9, 10, 10,  7,  6,  6,  6,  6,  7,  7,  8,  8,  9,  9, 10,
1515     10,  8,  7,  6,  7,  7,  7,  8,  8,  8,  9, 10, 10, 11,  9,  7,
1516      7,  7,  7,  8,  8,  9,  9,  9, 10, 10, 11,  9,  8,  8,  8,  8,
1517      8,  9,  9,  9, 10, 10, 11, 11,  9,  8,  8,  8,  8,  8,  9,  9,
1518     10, 10, 10, 11, 11, 10,  9,  9,  9,  9,  9,  9, 10, 10, 10, 11,
1519     11, 12, 10,  9,  9,  9,  9, 10, 10, 10, 10, 11, 11, 11, 12, 11,
1520     10,  9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 12, 11, 10, 10, 10,
1521     10, 10, 10, 11, 11, 12, 12, 12, 12
1522 ];
1523 const AAC_SPEC_CB10_CODES: &[u16] = &[
1524     0x022, 0x008, 0x01d, 0x026, 0x05f, 0x0d3, 0x1cf, 0x3d0,
1525     0x3d7, 0x3ed, 0x7f0, 0x7f6, 0xffd, 0x007, 0x000, 0x001,
1526     0x009, 0x020, 0x054, 0x060, 0x0d5, 0x0dc, 0x1d4, 0x3cd,
1527     0x3de, 0x7e7, 0x01c, 0x002, 0x006, 0x00c, 0x01e, 0x028,
1528     0x05b, 0x0cd, 0x0d9, 0x1ce, 0x1dc, 0x3d9, 0x3f1, 0x025,
1529     0x00b, 0x00a, 0x00d, 0x024, 0x057, 0x061, 0x0cc, 0x0dd,
1530     0x1cc, 0x1de, 0x3d3, 0x3e7, 0x05d, 0x021, 0x01f, 0x023,
1531     0x027, 0x059, 0x064, 0x0d8, 0x0df, 0x1d2, 0x1e2, 0x3dd,
1532     0x3ee, 0x0d1, 0x055, 0x029, 0x056, 0x058, 0x062, 0x0ce,
1533     0x0e0, 0x0e2, 0x1da, 0x3d4, 0x3e3, 0x7eb, 0x1c9, 0x05e,
1534     0x05a, 0x05c, 0x063, 0x0ca, 0x0da, 0x1c7, 0x1ca, 0x1e0,
1535     0x3db, 0x3e8, 0x7ec, 0x1e3, 0x0d2, 0x0cb, 0x0d0, 0x0d7,
1536     0x0db, 0x1c6, 0x1d5, 0x1d8, 0x3ca, 0x3da, 0x7ea, 0x7f1,
1537     0x1e1, 0x0d4, 0x0cf, 0x0d6, 0x0de, 0x0e1, 0x1d0, 0x1d6,
1538     0x3d1, 0x3d5, 0x3f2, 0x7ee, 0x7fb, 0x3e9, 0x1cd, 0x1c8,
1539     0x1cb, 0x1d1, 0x1d7, 0x1df, 0x3cf, 0x3e0, 0x3ef, 0x7e6,
1540     0x7f8, 0xffa, 0x3eb, 0x1dd, 0x1d3, 0x1d9, 0x1db, 0x3d2,
1541     0x3cc, 0x3dc, 0x3ea, 0x7ed, 0x7f3, 0x7f9, 0xff9, 0x7f2,
1542     0x3ce, 0x1e4, 0x3cb, 0x3d8, 0x3d6, 0x3e2, 0x3e5, 0x7e8,
1543     0x7f4, 0x7f5, 0x7f7, 0xffb, 0x7fa, 0x3ec, 0x3df, 0x3e1,
1544     0x3e4, 0x3e6, 0x3f0, 0x7e9, 0x7ef, 0xff8, 0xffe, 0xffc,
1545     0xfff
1546 ];
1547 const AAC_SPEC_CB11_BITS: &[u8] = &[
1548      4,  5,  6,  7,  8,  8,  9, 10, 10, 10, 11, 11, 12, 11, 12, 12,
1549     10,  5,  4,  5,  6,  7,  7,  8,  8,  9,  9,  9, 10, 10, 10, 10,
1550     11,  8,  6,  5,  5,  6,  7,  7,  8,  8,  8,  9,  9,  9, 10, 10,
1551     10, 10,  8,  7,  6,  6,  6,  7,  7,  8,  8,  8,  9,  9,  9, 10,
1552     10, 10, 10,  8,  8,  7,  7,  7,  7,  8,  8,  8,  8,  9,  9,  9,
1553     10, 10, 10, 10,  8,  8,  7,  7,  7,  7,  8,  8,  8,  9,  9,  9,
1554      9, 10, 10, 10, 10,  8,  9,  8,  8,  8,  8,  8,  8,  8,  9,  9,
1555      9, 10, 10, 10, 10, 10,  8,  9,  8,  8,  8,  8,  8,  8,  9,  9,
1556      9, 10, 10, 10, 10, 10, 10,  8, 10,  9,  8,  8,  9,  9,  9,  9,
1557      9, 10, 10, 10, 10, 10, 10, 11,  8, 10,  9,  9,  9,  9,  9,  9,
1558      9, 10, 10, 10, 10, 10, 10, 11, 11,  8, 11,  9,  9,  9,  9,  9,
1559      9, 10, 10, 10, 10, 10, 11, 10, 11, 11,  8, 11, 10,  9,  9, 10,
1560      9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11,  8, 11, 10, 10, 10,
1561     10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11,  9, 11, 10,  9,
1562      9, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11,  9, 11, 10,
1563     10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11,  9, 12,
1564     10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 12, 12,  9,
1565      9,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  9,
1566      5
1567 ];
1568 const AAC_SPEC_CB11_CODES: &[u16] = &[
1569     0x000, 0x006, 0x019, 0x03d, 0x09c, 0x0c6, 0x1a7, 0x390,
1570     0x3c2, 0x3df, 0x7e6, 0x7f3, 0xffb, 0x7ec, 0xffa, 0xffe,
1571     0x38e, 0x005, 0x001, 0x008, 0x014, 0x037, 0x042, 0x092,
1572     0x0af, 0x191, 0x1a5, 0x1b5, 0x39e, 0x3c0, 0x3a2, 0x3cd,
1573     0x7d6, 0x0ae, 0x017, 0x007, 0x009, 0x018, 0x039, 0x040,
1574     0x08e, 0x0a3, 0x0b8, 0x199, 0x1ac, 0x1c1, 0x3b1, 0x396,
1575     0x3be, 0x3ca, 0x09d, 0x03c, 0x015, 0x016, 0x01a, 0x03b,
1576     0x044, 0x091, 0x0a5, 0x0be, 0x196, 0x1ae, 0x1b9, 0x3a1,
1577     0x391, 0x3a5, 0x3d5, 0x094, 0x09a, 0x036, 0x038, 0x03a,
1578     0x041, 0x08c, 0x09b, 0x0b0, 0x0c3, 0x19e, 0x1ab, 0x1bc,
1579     0x39f, 0x38f, 0x3a9, 0x3cf, 0x093, 0x0bf, 0x03e, 0x03f,
1580     0x043, 0x045, 0x09e, 0x0a7, 0x0b9, 0x194, 0x1a2, 0x1ba,
1581     0x1c3, 0x3a6, 0x3a7, 0x3bb, 0x3d4, 0x09f, 0x1a0, 0x08f,
1582     0x08d, 0x090, 0x098, 0x0a6, 0x0b6, 0x0c4, 0x19f, 0x1af,
1583     0x1bf, 0x399, 0x3bf, 0x3b4, 0x3c9, 0x3e7, 0x0a8, 0x1b6,
1584     0x0ab, 0x0a4, 0x0aa, 0x0b2, 0x0c2, 0x0c5, 0x198, 0x1a4,
1585     0x1b8, 0x38c, 0x3a4, 0x3c4, 0x3c6, 0x3dd, 0x3e8, 0x0ad,
1586     0x3af, 0x192, 0x0bd, 0x0bc, 0x18e, 0x197, 0x19a, 0x1a3,
1587     0x1b1, 0x38d, 0x398, 0x3b7, 0x3d3, 0x3d1, 0x3db, 0x7dd,
1588     0x0b4, 0x3de, 0x1a9, 0x19b, 0x19c, 0x1a1, 0x1aa, 0x1ad,
1589     0x1b3, 0x38b, 0x3b2, 0x3b8, 0x3ce, 0x3e1, 0x3e0, 0x7d2,
1590     0x7e5, 0x0b7, 0x7e3, 0x1bb, 0x1a8, 0x1a6, 0x1b0, 0x1b2,
1591     0x1b7, 0x39b, 0x39a, 0x3ba, 0x3b5, 0x3d6, 0x7d7, 0x3e4,
1592     0x7d8, 0x7ea, 0x0ba, 0x7e8, 0x3a0, 0x1bd, 0x1b4, 0x38a,
1593     0x1c4, 0x392, 0x3aa, 0x3b0, 0x3bc, 0x3d7, 0x7d4, 0x7dc,
1594     0x7db, 0x7d5, 0x7f0, 0x0c1, 0x7fb, 0x3c8, 0x3a3, 0x395,
1595     0x39d, 0x3ac, 0x3ae, 0x3c5, 0x3d8, 0x3e2, 0x3e6, 0x7e4,
1596     0x7e7, 0x7e0, 0x7e9, 0x7f7, 0x190, 0x7f2, 0x393, 0x1be,
1597     0x1c0, 0x394, 0x397, 0x3ad, 0x3c3, 0x3c1, 0x3d2, 0x7da,
1598     0x7d9, 0x7df, 0x7eb, 0x7f4, 0x7fa, 0x195, 0x7f8, 0x3bd,
1599     0x39c, 0x3ab, 0x3a8, 0x3b3, 0x3b9, 0x3d0, 0x3e3, 0x3e5,
1600     0x7e2, 0x7de, 0x7ed, 0x7f1, 0x7f9, 0x7fc, 0x193, 0xffd,
1601     0x3dc, 0x3b6, 0x3c7, 0x3cc, 0x3cb, 0x3d9, 0x3da, 0x7d3,
1602     0x7e1, 0x7ee, 0x7ef, 0x7f5, 0x7f6, 0xffc, 0xfff, 0x19d,
1603     0x1c2, 0x0b5, 0x0a1, 0x096, 0x097, 0x095, 0x099, 0x0a0,
1604     0x0a2, 0x0ac, 0x0a9, 0x0b1, 0x0b3, 0x0bb, 0x0c0, 0x18f,
1605     0x004
1606 ];
1607
1608 const AAC_SPEC_BITS: [&[u8]; 11] = [
1609     AAC_SPEC_CB1_BITS, AAC_SPEC_CB2_BITS, AAC_SPEC_CB3_BITS, AAC_SPEC_CB4_BITS,
1610     AAC_SPEC_CB5_BITS, AAC_SPEC_CB6_BITS, AAC_SPEC_CB7_BITS, AAC_SPEC_CB8_BITS,
1611     AAC_SPEC_CB9_BITS, AAC_SPEC_CB10_BITS, AAC_SPEC_CB11_BITS
1612 ];
1613 const AAC_SPEC_CODES: [&[u16]; 11] = [
1614     AAC_SPEC_CB1_CODES, AAC_SPEC_CB2_CODES, AAC_SPEC_CB3_CODES, AAC_SPEC_CB4_CODES,
1615     AAC_SPEC_CB5_CODES, AAC_SPEC_CB6_CODES, AAC_SPEC_CB7_CODES, AAC_SPEC_CB8_CODES,
1616     AAC_SPEC_CB9_CODES, AAC_SPEC_CB10_CODES, AAC_SPEC_CB11_CODES
1617 ];
1618 const AAC_UNSIGNED_CODEBOOK: [bool; 11] = [
1619     false, false, true, true, false, false, true, true, true, true, true
1620 ];
1621 const AAC_CODEBOOK_MODULO: [u16; 7] = [
1622     9, 9, 8, 8, 13, 13, 17
1623 ];
1624
1625 const AAC_QUADS: [[i8; 4]; 81] = [
1626     [ 0, 0, 0, 0 ], [ 0, 0, 0, 1 ], [ 0, 0, 0, 2 ],
1627     [ 0, 0, 1, 0 ], [ 0, 0, 1, 1 ], [ 0, 0, 1, 2 ],
1628     [ 0, 0, 2, 0 ], [ 0, 0, 2, 1 ], [ 0, 0, 2, 2 ],
1629     [ 0, 1, 0, 0 ], [ 0, 1, 0, 1 ], [ 0, 1, 0, 2 ],
1630     [ 0, 1, 1, 0 ], [ 0, 1, 1, 1 ], [ 0, 1, 1, 2 ],
1631     [ 0, 1, 2, 0 ], [ 0, 1, 2, 1 ], [ 0, 1, 2, 2 ],
1632     [ 0, 2, 0, 0 ], [ 0, 2, 0, 1 ], [ 0, 2, 0, 2 ],
1633     [ 0, 2, 1, 0 ], [ 0, 2, 1, 1 ], [ 0, 2, 1, 2 ],
1634     [ 0, 2, 2, 0 ], [ 0, 2, 2, 1 ], [ 0, 2, 2, 2 ],
1635     [ 1, 0, 0, 0 ], [ 1, 0, 0, 1 ], [ 1, 0, 0, 2 ],
1636     [ 1, 0, 1, 0 ], [ 1, 0, 1, 1 ], [ 1, 0, 1, 2 ],
1637     [ 1, 0, 2, 0 ], [ 1, 0, 2, 1 ], [ 1, 0, 2, 2 ],
1638     [ 1, 1, 0, 0 ], [ 1, 1, 0, 1 ], [ 1, 1, 0, 2 ],
1639     [ 1, 1, 1, 0 ], [ 1, 1, 1, 1 ], [ 1, 1, 1, 2 ],
1640     [ 1, 1, 2, 0 ], [ 1, 1, 2, 1 ], [ 1, 1, 2, 2 ],
1641     [ 1, 2, 0, 0 ], [ 1, 2, 0, 1 ], [ 1, 2, 0, 2 ],
1642     [ 1, 2, 1, 0 ], [ 1, 2, 1, 1 ], [ 1, 2, 1, 2 ],
1643     [ 1, 2, 2, 0 ], [ 1, 2, 2, 1 ], [ 1, 2, 2, 2 ],
1644     [ 2, 0, 0, 0 ], [ 2, 0, 0, 1 ], [ 2, 0, 0, 2 ],
1645     [ 2, 0, 1, 0 ], [ 2, 0, 1, 1 ], [ 2, 0, 1, 2 ],
1646     [ 2, 0, 2, 0 ], [ 2, 0, 2, 1 ], [ 2, 0, 2, 2 ],
1647     [ 2, 1, 0, 0 ], [ 2, 1, 0, 1 ], [ 2, 1, 0, 2 ],
1648     [ 2, 1, 1, 0 ], [ 2, 1, 1, 1 ], [ 2, 1, 1, 2 ],
1649     [ 2, 1, 2, 0 ], [ 2, 1, 2, 1 ], [ 2, 1, 2, 2 ],
1650     [ 2, 2, 0, 0 ], [ 2, 2, 0, 1 ], [ 2, 2, 0, 2 ],
1651     [ 2, 2, 1, 0 ], [ 2, 2, 1, 1 ], [ 2, 2, 1, 2 ],
1652     [ 2, 2, 2, 0 ], [ 2, 2, 2, 1 ], [ 2, 2, 2, 2 ],
1653 ];
1654
1655 const DEFAULT_CHANNEL_MAP: [&str; 9] = [
1656     "",
1657     "C",
1658     "L,R",
1659     "C,L,R",
1660     "C,L,R,Cs",
1661     "C,L,R,Ls,Rs",
1662     "C,L,R,Ls,Rs,LFE",
1663     "",
1664     "C,L,R,Ls,Rs,Lss,Rss,LFE",
1665 ];
1666
1667 const SWB_OFFSET_48K_LONG: [usize; 49+1] = [
1668       0,   4,   8,  12,  16,  20,  24,  28,
1669      32,  36,  40,  48,  56,  64,  72,  80,
1670      88,  96, 108, 120, 132, 144, 160, 176,
1671     196, 216, 240, 264, 292, 320, 352, 384,
1672     416, 448, 480, 512, 544, 576, 608, 640,
1673     672, 704, 736, 768, 800, 832, 864, 896,
1674     928, 1024
1675 ];
1676 const SWB_OFFSET_48K_SHORT: [usize; 14+1] = [
1677     0, 4, 8, 12, 16, 20, 28, 36, 44, 56, 68, 80, 96, 112, 128
1678 ];
1679 const SWB_OFFSET_32K_LONG: [usize; 51+1] = [
1680       0,   4,   8,  12,  16,  20,  24,  28,
1681      32,  36,  40,  48,  56,  64,  72,  80,
1682      88,  96, 108, 120, 132, 144, 160, 176,
1683     196, 216, 240, 264, 292, 320, 352, 384,
1684     416, 448, 480, 512, 544, 576, 608, 640,
1685     672, 704, 736, 768, 800, 832, 864, 896,
1686     928, 960, 992, 1024
1687 ];
1688 const SWB_OFFSET_8K_LONG: [usize; 40+1] = [
1689       0,  12,  24,  36,  48,  60,  72,  84,
1690      96, 108, 120, 132, 144, 156, 172, 188,
1691     204, 220, 236, 252, 268, 288, 308, 328,
1692     348, 372, 396, 420, 448, 476, 508, 544,
1693     580, 620, 664, 712, 764, 820, 880, 944,
1694     1024
1695 ];
1696 const SWB_OFFSET_8K_SHORT: [usize; 15+1] = [
1697     0, 4, 8, 12, 16, 20, 24, 28, 36, 44, 52, 60, 72, 88, 108, 128
1698 ];
1699 const SWB_OFFSET_16K_LONG: [usize; 43+1] = [
1700       0,   8,  16,  24,  32,  40,  48,  56,
1701      64,  72,  80,  88, 100, 112, 124, 136,
1702     148, 160, 172, 184, 196, 212, 228, 244,
1703     260, 280, 300, 320, 344, 368, 396, 424,
1704     456, 492, 532, 572, 616, 664, 716, 772,
1705     832, 896, 960, 1024
1706 ];
1707 const SWB_OFFSET_16K_SHORT: [usize; 15+1] = [
1708     0, 4, 8, 12, 16, 20, 24, 28, 32, 40, 48, 60, 72, 88, 108, 128
1709 ];
1710 const SWB_OFFSET_24K_LONG: [usize; 47+1] = [
1711       0,   4,   8,  12,  16,  20,  24,  28,
1712      32,  36,  40,  44,  52,  60,  68,  76,
1713      84,  92, 100, 108, 116, 124, 136, 148,
1714     160, 172, 188, 204, 220, 240, 260, 284,
1715     308, 336, 364, 396, 432, 468, 508, 552,
1716     600, 652, 704, 768, 832, 896, 960, 1024
1717 ];
1718 const SWB_OFFSET_24K_SHORT: [usize; 15+1] = [
1719     0, 4, 8, 12, 16, 20, 24, 28, 36, 44, 52, 64, 76, 92, 108, 128
1720 ];
1721 const SWB_OFFSET_64K_LONG: [usize; 47+1] = [
1722       0,   4,   8,  12,  16,  20,  24,  28,
1723      32,  36,  40,  44,  48,  52,  56,  64,
1724      72,  80,  88, 100, 112, 124, 140, 156,
1725     172, 192, 216, 240, 268, 304, 344, 384,
1726     424, 464, 504, 544, 584, 624, 664, 704,
1727     744, 784, 824, 864, 904, 944, 984, 1024
1728 ];
1729 const SWB_OFFSET_64K_SHORT: [usize; 12+1] = [
1730     0, 4, 8, 12, 16, 20, 24, 32, 40, 48, 64, 92, 128
1731 ];
1732 const SWB_OFFSET_96K_LONG: [usize; 41+1] = [
1733       0,   4,   8,  12,  16,  20,  24,  28,
1734      32,  36,  40,  44,  48,  52,  56,  64,
1735      72,  80,  88,  96, 108, 120, 132, 144,
1736     156, 172, 188, 212, 240, 276, 320, 384,
1737     448, 512, 576, 640, 704, 768, 832, 896,
1738     960, 1024
1739 ];
1740
1741 #[derive(Clone,Copy)]
1742 struct GASubbandInfo {
1743     min_srate:     u32,
1744     long_bands:    &'static [usize],
1745     short_bands:   &'static [usize],
1746 }
1747
1748 impl GASubbandInfo {
1749     fn find(srate: u32) -> GASubbandInfo {
1750         for sbi in AAC_SUBBAND_INFO.iter() {
1751             if srate >= sbi.min_srate {
1752                 return *sbi;
1753             }
1754         }
1755         unreachable!("")
1756     }
1757     fn find_idx(srate: u32) -> usize {
1758         for (i, sbi) in AAC_SUBBAND_INFO.iter().enumerate() {
1759             if srate >= sbi.min_srate {
1760                 return i;
1761             }
1762         }
1763         unreachable!("")
1764     }
1765 }
1766
1767 const AAC_SUBBAND_INFO: [GASubbandInfo; 12] = [
1768     GASubbandInfo { min_srate: 92017, long_bands: &SWB_OFFSET_96K_LONG, short_bands: &SWB_OFFSET_64K_SHORT }, //96K
1769     GASubbandInfo { min_srate: 75132, long_bands: &SWB_OFFSET_96K_LONG, short_bands: &SWB_OFFSET_64K_SHORT }, //88.2K
1770     GASubbandInfo { min_srate: 55426, long_bands: &SWB_OFFSET_64K_LONG, short_bands: &SWB_OFFSET_64K_SHORT }, //64K
1771     GASubbandInfo { min_srate: 46009, long_bands: &SWB_OFFSET_48K_LONG, short_bands: &SWB_OFFSET_48K_SHORT }, //48K
1772     GASubbandInfo { min_srate: 37566, long_bands: &SWB_OFFSET_48K_LONG, short_bands: &SWB_OFFSET_48K_SHORT }, //44.1K
1773     GASubbandInfo { min_srate: 27713, long_bands: &SWB_OFFSET_32K_LONG, short_bands: &SWB_OFFSET_48K_SHORT }, //32K
1774     GASubbandInfo { min_srate: 23004, long_bands: &SWB_OFFSET_24K_LONG, short_bands: &SWB_OFFSET_24K_SHORT }, //24K
1775     GASubbandInfo { min_srate: 18783, long_bands: &SWB_OFFSET_24K_LONG, short_bands: &SWB_OFFSET_24K_SHORT }, //22.05K
1776     GASubbandInfo { min_srate: 13856, long_bands: &SWB_OFFSET_16K_LONG, short_bands: &SWB_OFFSET_16K_SHORT }, //16K
1777     GASubbandInfo { min_srate: 11502, long_bands: &SWB_OFFSET_16K_LONG, short_bands: &SWB_OFFSET_16K_SHORT }, //12K
1778     GASubbandInfo { min_srate:  9391, long_bands: &SWB_OFFSET_16K_LONG, short_bands: &SWB_OFFSET_16K_SHORT }, //11.025K
1779     GASubbandInfo { min_srate:     0, long_bands: &SWB_OFFSET_8K_LONG,  short_bands: &SWB_OFFSET_8K_SHORT  }, //8K
1780 ];