| 1 | use nihav_core::codecs::{DecoderResult, DecoderError}; |
| 2 | use nihav_core::io::bitreader::*; |
| 3 | use super::mp2data::*; |
| 4 | |
| 5 | #[derive(Default)] |
| 6 | pub struct MP2Data { |
| 7 | pub mpeg1: bool, |
| 8 | pub sf_idx: usize, |
| 9 | pub br_idx: usize, |
| 10 | alloc: [[u8; 32]; 2], |
| 11 | scfsi: [[u8; 32]; 2], |
| 12 | scale: [[[u8; 3]; 32]; 2], |
| 13 | } |
| 14 | |
| 15 | fn unquant(val: u8, levels: i16, scale: f32) -> f32 { |
| 16 | (((i16::from(val) << 1) + 1 - levels) as f32) * scale / (levels as f32) |
| 17 | } |
| 18 | |
| 19 | fn read3samples(br: &mut BitReader, qbits: i8, scale: f32, band: usize, dst: &mut [[f32; 32]]) -> DecoderResult<()> { |
| 20 | if qbits > 0 { |
| 21 | let bits = qbits as u8; |
| 22 | let maxval = (1 << bits) - 1; |
| 23 | dst[0][band] = unquant(br.read(bits)? as u8, maxval, scale); |
| 24 | dst[1][band] = unquant(br.read(bits)? as u8, maxval, scale); |
| 25 | dst[2][band] = unquant(br.read(bits)? as u8, maxval, scale); |
| 26 | } else { |
| 27 | let samplecode = br.read(-qbits as u8)? as usize; |
| 28 | match qbits { |
| 29 | -5 => { |
| 30 | for i in 0..3 { |
| 31 | dst[i][band] = unquant(GROUP3[samplecode][i], 3, scale); |
| 32 | } |
| 33 | }, |
| 34 | -7 => { |
| 35 | for i in 0..3 { |
| 36 | dst[i][band] = unquant(GROUP5[samplecode][i], 5, scale); |
| 37 | } |
| 38 | }, |
| 39 | -10 => { |
| 40 | for i in 0..3 { |
| 41 | dst[i][band] = unquant(GROUP9[samplecode][i], 9, scale); |
| 42 | } |
| 43 | }, |
| 44 | _ => unreachable!(), |
| 45 | }; |
| 46 | } |
| 47 | Ok(()) |
| 48 | } |
| 49 | |
| 50 | fn read3samples_joint(br: &mut BitReader, qbits: i8, scale0: f32, scale1: f32, band: usize, gr: usize, dst: &mut [[[f32; 32]; 36]; 2]) -> DecoderResult<()> { |
| 51 | if qbits > 0 { |
| 52 | let bits = qbits as u8; |
| 53 | let maxval = (1 << bits) - 1; |
| 54 | for i in 0..3 { |
| 55 | let val = br.read(bits)? as u8; |
| 56 | dst[0][gr * 3 + i][band] = unquant(val, maxval, scale0); |
| 57 | dst[1][gr * 3 + i][band] = unquant(val, maxval, scale1); |
| 58 | } |
| 59 | } else { |
| 60 | let samplecode = br.read(-qbits as u8)? as usize; |
| 61 | match qbits { |
| 62 | -5 => { |
| 63 | for i in 0..3 { |
| 64 | dst[0][gr * 3 + i][band] = unquant(GROUP3[samplecode][i], 3, scale0); |
| 65 | dst[1][gr * 3 + i][band] = unquant(GROUP3[samplecode][i], 3, scale1); |
| 66 | } |
| 67 | }, |
| 68 | -7 => { |
| 69 | for i in 0..3 { |
| 70 | dst[0][gr * 3 + i][band] = unquant(GROUP5[samplecode][i], 5, scale0); |
| 71 | dst[1][gr * 3 + i][band] = unquant(GROUP5[samplecode][i], 5, scale1); |
| 72 | } |
| 73 | }, |
| 74 | -10 => { |
| 75 | for i in 0..3 { |
| 76 | dst[0][gr * 3 + i][band] = unquant(GROUP9[samplecode][i], 9, scale0); |
| 77 | dst[1][gr * 3 + i][band] = unquant(GROUP9[samplecode][i], 9, scale1); |
| 78 | } |
| 79 | }, |
| 80 | _ => unreachable!(), |
| 81 | }; |
| 82 | } |
| 83 | Ok(()) |
| 84 | } |
| 85 | |
| 86 | impl MP2Data { |
| 87 | pub fn new() -> Self { Self::default() } |
| 88 | pub fn read_layer2(&mut self, br: &mut BitReader, channels: usize, out: &mut [[[f32; 32]; 36]; 2], mode: u8, mode_extension: u8) -> DecoderResult<()> { |
| 89 | let (ba_bits, ba_quants) = if self.mpeg1 { |
| 90 | if channels == 1 { |
| 91 | (LAYER2_BITS[self.sf_idx][self.br_idx], LAYER2_ALLOC[self.br_idx]) |
| 92 | } else { |
| 93 | let br_idx = HALF_BITRATE_IDX[self.br_idx] as usize; |
| 94 | (LAYER2_BITS[self.sf_idx][br_idx], LAYER2_ALLOC[br_idx]) |
| 95 | } |
| 96 | } else { |
| 97 | (BITS_B2LFE, ALLOC_B2LFE) |
| 98 | }; |
| 99 | let mut sblimit = ba_bits.len() - 1; |
| 100 | while sblimit > 0 && ba_bits[sblimit - 1] == 0 { |
| 101 | sblimit -= 1; |
| 102 | } |
| 103 | if sblimit == 0 { |
| 104 | return Err(DecoderError::Bug); |
| 105 | } |
| 106 | |
| 107 | *out = [[[0.0; 32]; 36]; 2]; |
| 108 | if channels == 1 { |
| 109 | for (bits, &b) in self.alloc[0][..sblimit].iter_mut().zip(ba_bits.iter()) { |
| 110 | *bits = br.read(b)? as u8; |
| 111 | } |
| 112 | for (scf, &alloc) in self.scfsi[0][..sblimit].iter_mut().zip(self.alloc[0].iter()) { |
| 113 | if alloc != 0 { |
| 114 | *scf = br.read(2)? as u8; |
| 115 | } |
| 116 | } |
| 117 | for (band, scales) in self.scale[0].iter_mut().take(sblimit).enumerate() { |
| 118 | if self.alloc[0][band] == 0 { |
| 119 | continue; |
| 120 | } |
| 121 | scales[0] = br.read(6)? as u8; |
| 122 | match self.scfsi[0][band] { |
| 123 | 0 => { |
| 124 | scales[1] = br.read(6)? as u8; |
| 125 | scales[2] = br.read(6)? as u8; |
| 126 | }, |
| 127 | 1 => { |
| 128 | scales[1] = scales[0]; |
| 129 | scales[2] = br.read(6)? as u8; |
| 130 | }, |
| 131 | 2 => { |
| 132 | scales[1] = scales[0]; |
| 133 | scales[2] = scales[0]; |
| 134 | }, |
| 135 | _ => { |
| 136 | scales[1] = br.read(6)? as u8; |
| 137 | scales[2] = scales[1]; |
| 138 | }, |
| 139 | }; |
| 140 | } |
| 141 | |
| 142 | for gr in 0..12 { |
| 143 | for band in 0..sblimit { |
| 144 | if self.alloc[0][band] == 0 { |
| 145 | continue; |
| 146 | } |
| 147 | let scale = QUANTS[self.scale[0][band][gr / 4] as usize]; |
| 148 | let qbits = ba_quants[band][self.alloc[0][band] as usize]; |
| 149 | read3samples(br, qbits, scale, band, &mut out[0][gr * 3..])?; |
| 150 | } |
| 151 | } |
| 152 | } else { |
| 153 | let mut bound = if mode == 1 { |
| 154 | (mode_extension as usize + 1) * 4 |
| 155 | } else { |
| 156 | sblimit |
| 157 | }; |
| 158 | while bound > 0 && ba_bits[bound - 1] == 0 { |
| 159 | bound -= 1; |
| 160 | } |
| 161 | |
| 162 | for band in 0..sblimit { |
| 163 | self.alloc[0][band] = br.read(ba_bits[band])? as u8; |
| 164 | if band < bound { |
| 165 | self.alloc[1][band] = br.read(ba_bits[band])? as u8; |
| 166 | } else { |
| 167 | self.alloc[1][band] = self.alloc[0][band]; |
| 168 | } |
| 169 | } |
| 170 | for band in 0..sblimit { |
| 171 | for ch in 0..2 { |
| 172 | if self.alloc[ch][band] != 0 { |
| 173 | self.scfsi[ch][band] = br.read(2)? as u8; |
| 174 | } |
| 175 | } |
| 176 | } |
| 177 | for band in 0..sblimit { |
| 178 | for ch in 0..2 { |
| 179 | if self.alloc[ch][band] == 0 { |
| 180 | continue; |
| 181 | } |
| 182 | let scales = &mut self.scale[ch][band]; |
| 183 | scales[0] = br.read(6)? as u8; |
| 184 | match self.scfsi[ch][band] { |
| 185 | 0 => { |
| 186 | scales[1] = br.read(6)? as u8; |
| 187 | scales[2] = br.read(6)? as u8; |
| 188 | }, |
| 189 | 1 => { |
| 190 | scales[1] = scales[0]; |
| 191 | scales[2] = br.read(6)? as u8; |
| 192 | }, |
| 193 | 2 => { |
| 194 | scales[1] = scales[0]; |
| 195 | scales[2] = scales[0]; |
| 196 | }, |
| 197 | _ => { |
| 198 | scales[1] = br.read(6)? as u8; |
| 199 | scales[2] = scales[1]; |
| 200 | }, |
| 201 | }; |
| 202 | } |
| 203 | } |
| 204 | for gr in 0..12 { |
| 205 | for band in 0..bound { |
| 206 | for ch in 0..2 { |
| 207 | if self.alloc[ch][band] == 0 { |
| 208 | continue; |
| 209 | } |
| 210 | let scale = QUANTS[self.scale[ch][band][gr / 4] as usize]; |
| 211 | let qbits = ba_quants[band][self.alloc[ch][band] as usize]; |
| 212 | read3samples(br, qbits, scale, band, &mut out[ch][gr * 3..])?; |
| 213 | } |
| 214 | } |
| 215 | for band in bound..sblimit { |
| 216 | if self.alloc[0][band] == 0 { |
| 217 | continue; |
| 218 | } |
| 219 | let scale0 = QUANTS[self.scale[0][band][gr / 4] as usize]; |
| 220 | let scale1 = QUANTS[self.scale[1][band][gr / 4] as usize]; |
| 221 | let qbits = ba_quants[band][self.alloc[0][band] as usize]; |
| 222 | read3samples_joint(br, qbits, scale0, scale1, band, gr, out)?; |
| 223 | } |
| 224 | } |
| 225 | } |
| 226 | |
| 227 | Ok(()) |
| 228 | } |
| 229 | pub fn reset(&mut self) { |
| 230 | } |
| 231 | } |