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use nihav_core::codecs::{DecoderResult, DecoderError};
use nihav_core::io::bitreader::*;
use std::fmt;
#[allow(non_camel_case_types)]
#[derive(Clone,Copy,PartialEq)]
pub enum M4AType {
None,
Main,
LC,
SSR,
LTP,
SBR,
Scalable,
TwinVQ,
CELP,
HVXC,
TTSI,
MainSynth,
WavetableSynth,
GeneralMIDI,
Algorithmic,
ER_AAC_LC,
ER_AAC_LTP,
ER_AAC_Scalable,
ER_TwinVQ,
ER_BSAC,
ER_AAC_LD,
ER_CELP,
ER_HVXC,
ER_HILN,
ER_Parametric,
SSC,
PS,
MPEGSurround,
Layer1,
Layer2,
Layer3,
DST,
ALS,
SLS,
SLSNonCore,
ER_AAC_ELD,
SMRSimple,
SMRMain,
Reserved,
Unknown,
}
const M4A_TYPES: &[M4AType] = &[
M4AType::None, M4AType::Main, M4AType::LC, M4AType::SSR,
M4AType::LTP, M4AType::SBR, M4AType::Scalable, M4AType::TwinVQ,
M4AType::CELP, M4AType::HVXC, M4AType::Reserved, M4AType::Reserved,
M4AType::TTSI, M4AType::MainSynth, M4AType::WavetableSynth, M4AType::GeneralMIDI,
M4AType::Algorithmic, M4AType::ER_AAC_LC, M4AType::Reserved, M4AType::ER_AAC_LTP,
M4AType::ER_AAC_Scalable, M4AType::ER_TwinVQ, M4AType::ER_BSAC, M4AType::ER_AAC_LD,
M4AType::ER_CELP, M4AType::ER_HVXC, M4AType::ER_HILN, M4AType::ER_Parametric,
M4AType::SSC, M4AType::PS, M4AType::MPEGSurround, M4AType::Reserved /*escape*/,
M4AType::Layer1, M4AType::Layer2, M4AType::Layer3, M4AType::DST,
M4AType::ALS, M4AType::SLS, M4AType::SLSNonCore, M4AType::ER_AAC_ELD,
M4AType::SMRSimple, M4AType::SMRMain,
];
const M4A_TYPE_NAMES: &[&str] = &[
"None", "AAC Main", "AAC LC", "AAC SSR", "AAC LTP", "SBR", "AAC Scalable", "TwinVQ", "CELP", "HVXC",
/*"(reserved10)", "(reserved11)", */ "TTSI",
"Main synthetic", "Wavetable synthesis", "General MIDI", "Algorithmic Synthesis and Audio FX",
"ER AAC LC", /*"(reserved18)",*/ "ER AAC LTP", "ER AAC Scalable", "ER TwinVQ", "ER BSAC", "ER AAC LD",
"ER CELP", "ER HVXC", "ER HILN", "ER Parametric", "SSC", "PS", "MPEG Surround", /*"(escape)",*/
"Layer-1", "Layer-2", "Layer-3", "DST", "ALS", "SLS", "SLS non-core", "ER AAC ELD", "SMR Simple", "SMR Main",
"(reserved)", "(unknown)",
];
impl fmt::Display for M4AType {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", M4A_TYPE_NAMES[*self as usize])
}
}
const AAC_SAMPLE_RATES: [u32; 16] = [
96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050,
16000, 12000, 11025, 8000, 7350, 0, 0, 0
];
const AAC_CHANNELS: [usize; 8] = [ 0, 1, 2, 3, 4, 5, 6, 8 ];
pub struct M4AInfo {
pub otype: M4AType,
pub srate: u32,
pub channels: usize,
pub samples: usize,
pub sbr_ps_info: Option<(u32, usize)>,
pub sbr_present: bool,
pub ps_present: bool,
}
impl M4AInfo {
pub fn new() -> Self {
Self {
otype: M4AType::None,
srate: 0,
channels: 0,
samples: 0,
sbr_ps_info: Option::None,
sbr_present: false,
ps_present: false,
}
}
fn read_object_type(br: &mut BitReader) -> DecoderResult<M4AType> {
let otypeidx;
if br.peek(5) == 31 {
br.skip(5)?;
otypeidx = (br.read(6)? as usize) + 32;
} else {
otypeidx = br.read(5)? as usize;
}
if otypeidx >= M4A_TYPES.len() {
Ok(M4AType::Unknown)
} else {
Ok(M4A_TYPES[otypeidx])
}
}
fn read_sampling_frequency(br: &mut BitReader) -> DecoderResult<u32> {
if br.peek(4) == 15 {
let srate = br.read(24)?;
Ok(srate)
} else {
let srate_idx = br.read(4)? as usize;
Ok(AAC_SAMPLE_RATES[srate_idx])
}
}
fn read_channel_config(br: &mut BitReader) -> DecoderResult<usize> {
let chidx = br.read(4)? as usize;
if chidx < AAC_CHANNELS.len() {
Ok(AAC_CHANNELS[chidx])
} else {
Ok(chidx)
}
}
pub fn read(&mut self, src: &[u8]) -> DecoderResult<()> {
let mut br = BitReader::new(src, BitReaderMode::BE);
self.otype = Self::read_object_type(&mut br)?;
self.srate = Self::read_sampling_frequency(&mut br)?;
validate!(self.srate > 0);
self.channels = Self::read_channel_config(&mut br)?;
if (self.otype == M4AType::SBR) || (self.otype == M4AType::PS) {
let ext_srate = Self::read_sampling_frequency(&mut br)?;
self.otype = Self::read_object_type(&mut br)?;
let ext_chans;
if self.otype == M4AType::ER_BSAC {
ext_chans = Self::read_channel_config(&mut br)?;
} else {
ext_chans = 0;
}
self.sbr_ps_info = Some((ext_srate, ext_chans));
}
match self.otype {
M4AType::Main | M4AType::LC | M4AType::SSR | M4AType::Scalable | M4AType::TwinVQ |
M4AType::ER_AAC_LC | M4AType::ER_AAC_LTP | M4AType::ER_AAC_Scalable | M4AType::ER_TwinVQ |
M4AType::ER_BSAC | M4AType::ER_AAC_LD => {
// GASpecificConfig
let short_frame = br.read_bool()?;
self.samples = if short_frame { 960 } else { 1024 };
let depends_on_core = br.read_bool()?;
if depends_on_core {
let _delay = br.read(14)?;
}
let extension_flag = br.read_bool()?;
if self.channels == 0 {
let (channels, sf_code) = skimp_through_program_config_element(&mut br)?;
validate!(channels > 0);
self.channels = channels;
validate!(AAC_SAMPLE_RATES[sf_code] != 0);
self.srate = AAC_SAMPLE_RATES[sf_code];
}
if (self.otype == M4AType::Scalable) || (self.otype == M4AType::ER_AAC_Scalable) {
let _layer = br.read(3)?;
}
if extension_flag {
if self.otype == M4AType::ER_BSAC {
let _num_subframes = br.read(5)? as usize;
let _layer_length = br.read(11)?;
}
if (self.otype == M4AType::ER_AAC_LC) ||
(self.otype == M4AType::ER_AAC_LTP) ||
(self.otype == M4AType::ER_AAC_Scalable) ||
(self.otype == M4AType::ER_AAC_LD) {
let _section_data_resilience = br.read_bool()?;
let _scalefactors_resilience = br.read_bool()?;
let _spectral_data_resilience = br.read_bool()?;
}
let extension_flag3 = br.read_bool()?;
if extension_flag3 {
unimplemented!("version3 extensions");
}
}
},
M4AType::CELP => { unimplemented!("CELP config"); },
M4AType::HVXC => { unimplemented!("HVXC config"); },
M4AType::TTSI => { unimplemented!("TTS config"); },
M4AType::MainSynth | M4AType::WavetableSynth | M4AType::GeneralMIDI | M4AType::Algorithmic => { unimplemented!("structured audio config"); },
M4AType::ER_CELP => { unimplemented!("ER CELP config"); },
M4AType::ER_HVXC => { unimplemented!("ER HVXC config"); },
M4AType::ER_HILN | M4AType::ER_Parametric => { unimplemented!("parametric config"); },
M4AType::SSC => { unimplemented!("SSC config"); },
M4AType::MPEGSurround => {
br.skip(1)?; // sacPayloadEmbedding
unimplemented!("MPEG Surround config");
},
M4AType::Layer1 | M4AType::Layer2 | M4AType::Layer3 => { unimplemented!("MPEG Layer 1/2/3 config"); },
M4AType::DST => { unimplemented!("DST config"); },
M4AType::ALS => {
br.skip(5)?; // fillBits
unimplemented!("ALS config");
},
M4AType::SLS | M4AType::SLSNonCore => { unimplemented!("SLS config"); },
M4AType::ER_AAC_ELD => { unimplemented!("ELD config"); },
M4AType::SMRSimple | M4AType::SMRMain => { unimplemented!("symbolic music config"); },
_ => {},
};
match self.otype {
M4AType::ER_AAC_LC | M4AType::ER_AAC_LTP | M4AType::ER_AAC_Scalable | M4AType::ER_TwinVQ |
M4AType::ER_BSAC | M4AType::ER_AAC_LD | M4AType::ER_CELP | M4AType::ER_HVXC |
M4AType::ER_HILN | M4AType::ER_Parametric | M4AType::ER_AAC_ELD => {
let ep_config = br.read(2)?;
if (ep_config == 2) || (ep_config == 3) {
unimplemented!("error protection config");
}
if ep_config == 3 {
let direct_mapping = br.read_bool()?;
validate!(direct_mapping);
}
},
_ => {},
};
if self.sbr_ps_info.is_some() && (br.left() >= 16) {
let sync = br.read(11)?;
if sync == 0x2B7 {
let ext_otype = Self::read_object_type(&mut br)?;
if ext_otype == M4AType::SBR {
self.sbr_present = br.read_bool()?;
if self.sbr_present {
let _ext_srate = Self::read_sampling_frequency(&mut br)?;
if br.left() >= 12 {
let sync = br.read(11)?;
if sync == 0x548 {
self.ps_present = br.read_bool()?;
}
}
}
}
if ext_otype == M4AType::PS {
self.sbr_present = br.read_bool()?;
if self.sbr_present {
let _ext_srate = Self::read_sampling_frequency(&mut br)?;
}
let _ext_channels = br.read(4)?;
}
}
}
Ok(())
}
}
pub fn skimp_through_program_config_element(br: &mut BitReader) -> DecoderResult<(usize, usize)> {
let _id = br.read(4)?;
let _object_type = br.read(2)?;
let sampling_frequency_index = br.read(4)? as usize;
let num_front_channel_elements = br.read(4)? as usize;
let num_side_channel_elements = br.read(4)? as usize;
let num_back_channel_elements = br.read(4)? as usize;
let num_lfe_channel_elements = br.read(2)? as usize;
let num_assoc_data_elements = br.read(3)? as usize;
let num_valid_cc_elements = br.read(4)? as usize;
let mono_mixdown_present = br.read_bool()?;
if mono_mixdown_present {
let _mono_mixdown_element_number = br.read(4)?;
}
let stereo_mixdown_present = br.read_bool()?;
if stereo_mixdown_present {
let _stereo_mixdown_element_number = br.read(4)?;
}
let matrix_mixdown_idx_present = br.read_bool()?;
if matrix_mixdown_idx_present {
let _matrix_mixdown_idx = br.read(2)?;
let _pseudo_surround_enable = br.read_bool()?;
}
for _i in 0..num_front_channel_elements {
let _front_element_is_cpe = br.read_bool()?;
let _front_element_tag_select = br.read(4)?;
}
for _i in 0..num_side_channel_elements {
let _side_element_is_cpe = br.read_bool()?;
let _side_element_tag_select = br.read(4)?;
}
for _i in 0..num_back_channel_elements {
let _back_element_is_cpe = br.read_bool()?;
let _back_element_tag_select = br.read(4)?;
}
for _i in 0..num_lfe_channel_elements {
let _lfe_element_tag_select = br.read(4)?;
}
for _i in 0..num_assoc_data_elements {
let _assoc_data_element_tag_select = br.read(4)?;
}
for _i in 0..num_valid_cc_elements {
let _cc_element_is_ind_sw = br.read_bool()?;
let _valid_cc_element_tag_select = br.read(4)?;
}
br.align();
let comment_field_bytes = br.read(8)?;
br.skip(comment_field_bytes * 8)?;
Ok((num_front_channel_elements +
num_side_channel_elements +
num_back_channel_elements +
num_lfe_channel_elements, sampling_frequency_index))
}
impl fmt::Display for M4AInfo {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "MPEG 4 Audio {}, {} Hz, {} channels, {} samples per frame",
self.otype, self.srate, self.channels, self.samples)
}
}
|
