| 1 | use nihav_core::codecs::{DecoderError, DecoderResult}; |
| 2 | use nihav_core::io::bitreader::*; |
| 3 | use nihav_core::io::intcode::*; |
| 4 | |
| 5 | pub struct RiceParams { |
| 6 | k: u8, |
| 7 | sum: u32 |
| 8 | } |
| 9 | |
| 10 | impl RiceParams { |
| 11 | pub fn new() -> Self { |
| 12 | let k = 10; |
| 13 | Self { k, sum: 1 << (k + 4) } |
| 14 | } |
| 15 | fn update(&mut self, val: u32) { |
| 16 | let limit = if self.k > 0 { 1 << (self.k + 4) } else { 0 }; |
| 17 | self.sum -= (self.sum + 16) >> 5; |
| 18 | self.sum += (val + 1) / 2; |
| 19 | if self.sum < limit { |
| 20 | self.k -= 1; |
| 21 | } else if (self.sum >= (1 << (self.k + 5))) && (self.k < 27) { |
| 22 | self.k += 1; |
| 23 | } |
| 24 | } |
| 25 | fn update_old(&mut self, val: u32) { |
| 26 | let limit = if self.k > 0 { 1 << (self.k + 4) } else { 0 }; |
| 27 | self.sum -= (self.sum + 8) >> 4; |
| 28 | self.sum += val; |
| 29 | if self.sum < limit { |
| 30 | self.k -= 1; |
| 31 | } else if (self.sum >= (1 << (self.k + 5))) && (self.k < 24) { |
| 32 | self.k += 1; |
| 33 | } |
| 34 | } |
| 35 | } |
| 36 | |
| 37 | pub struct RiceCoder<'a> { |
| 38 | br: BitReader<'a>, |
| 39 | rice_x: RiceParams, |
| 40 | rice_y: RiceParams, |
| 41 | } |
| 42 | |
| 43 | impl<'a> RiceCoder<'a> { |
| 44 | pub fn new(br: BitReader<'a>) -> Self { |
| 45 | Self { |
| 46 | br, |
| 47 | rice_x: RiceParams::new(), |
| 48 | rice_y: RiceParams::new(), |
| 49 | } |
| 50 | } |
| 51 | } |
| 52 | |
| 53 | struct ARangeCoder<'a> { |
| 54 | src: &'a [u8], |
| 55 | pos: usize, |
| 56 | low: u32, |
| 57 | range: u32, |
| 58 | help: u32, |
| 59 | buffer: u32, |
| 60 | error: bool, |
| 61 | } |
| 62 | |
| 63 | pub struct RangeCoder<'a> { |
| 64 | rc: ARangeCoder<'a>, |
| 65 | rice_x: RiceParams, |
| 66 | rice_y: RiceParams, |
| 67 | } |
| 68 | |
| 69 | impl<'a> RangeCoder<'a> { |
| 70 | pub fn new(src: &'a [u8]) -> Self { |
| 71 | Self { |
| 72 | rc: ARangeCoder::new(src), |
| 73 | rice_x: RiceParams::new(), |
| 74 | rice_y: RiceParams::new(), |
| 75 | } |
| 76 | } |
| 77 | fn had_errors(&self) -> bool { self.rc.error } |
| 78 | } |
| 79 | |
| 80 | const RANGE_BITS: u8 = 32; |
| 81 | const TOP: u32 = 1 << (RANGE_BITS - 1); |
| 82 | const BOTTOM: u32 = TOP >> 8; |
| 83 | const START_BITS: u8 = ((RANGE_BITS - 2) & 7) + 1; |
| 84 | |
| 85 | const MAX_MODEL_VAL: u32 = 63; |
| 86 | |
| 87 | impl<'a> ARangeCoder<'a> { |
| 88 | fn new(src: &'a [u8]) -> Self { |
| 89 | let buffer = u32::from(src[0]); |
| 90 | Self { |
| 91 | src: &src[1..], |
| 92 | pos: 0, |
| 93 | low: buffer >> (8 - START_BITS), |
| 94 | range: 1 << START_BITS, |
| 95 | help: 0, |
| 96 | buffer, |
| 97 | error: false, |
| 98 | } |
| 99 | } |
| 100 | fn reset(&mut self) { |
| 101 | if self.pos == 0 { |
| 102 | self.error = true; |
| 103 | } else { |
| 104 | self.pos -= 1; |
| 105 | } |
| 106 | if self.pos < self.src.len() - 1 { |
| 107 | self.buffer = u32::from(self.src[self.pos]); |
| 108 | self.pos += 1; |
| 109 | } |
| 110 | self.low = self.buffer >> (8 - START_BITS); |
| 111 | self.range = 1 << START_BITS; |
| 112 | self.help = 0; |
| 113 | } |
| 114 | fn normalise(&mut self) { |
| 115 | while self.range <= BOTTOM { |
| 116 | self.buffer <<= 8; |
| 117 | if self.pos < self.src.len() { |
| 118 | self.buffer |= u32::from(self.src[self.pos]); |
| 119 | self.pos += 1; |
| 120 | } else { |
| 121 | self.error = true; |
| 122 | } |
| 123 | self.low <<= 8; |
| 124 | self.low |= (self.buffer >> 1) & 0xFF; |
| 125 | self.range <<= 8; |
| 126 | } |
| 127 | } |
| 128 | fn get_freq(&mut self, freq: u32) -> u32 { |
| 129 | self.normalise(); |
| 130 | self.help = self.range / freq; |
| 131 | self.low / self.help |
| 132 | } |
| 133 | fn get_bits(&mut self, bits: u8) -> u32 { |
| 134 | self.normalise(); |
| 135 | self.help = self.range >> bits; |
| 136 | self.low / self.help |
| 137 | } |
| 138 | fn update(&mut self, interval: u32, low: u32) { |
| 139 | self.low -= self.help * low; |
| 140 | self.range = self.help * interval; |
| 141 | } |
| 142 | fn decode_freq(&mut self, freq: u32) -> u32 { |
| 143 | let sym = self.get_freq(freq); |
| 144 | self.update(1, sym); |
| 145 | sym |
| 146 | } |
| 147 | fn decode_bits(&mut self, bits: u8) -> u32 { |
| 148 | let sym = self.get_bits(bits); |
| 149 | self.update(1, sym); |
| 150 | sym |
| 151 | } |
| 152 | fn decode_symbol(&mut self, freqs: &[u32; 22]) -> u32 { |
| 153 | let bits = self.get_bits(16); |
| 154 | if bits > 65492 { |
| 155 | let sym = bits + MAX_MODEL_VAL - 65535; |
| 156 | self.update(1, bits); |
| 157 | if bits > 65536 { |
| 158 | self.error = true; |
| 159 | } |
| 160 | sym |
| 161 | } else { |
| 162 | let mut sym = 0usize; |
| 163 | while freqs[sym + 1] <= bits { |
| 164 | sym += 1; |
| 165 | } |
| 166 | self.update(freqs[sym + 1] - freqs[sym], freqs[sym]); |
| 167 | sym as u32 |
| 168 | } |
| 169 | } |
| 170 | } |
| 171 | |
| 172 | pub enum Coder<'a> { |
| 173 | Rice(RiceCoder<'a>), |
| 174 | Range(RangeCoder<'a>), |
| 175 | } |
| 176 | |
| 177 | fn to_signed(val: u32) -> i32 { |
| 178 | if (val & 1) != 0 { |
| 179 | (val >> 1) as i32 + 1 |
| 180 | } else { |
| 181 | -((val >> 1) as i32) |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | pub fn decode_mono_dummy(_c: &mut Coder, _l: &mut [i32]) -> DecoderResult<()> { |
| 186 | unreachable!(); |
| 187 | } |
| 188 | pub fn decode_stereo_dummy(_c: &mut Coder, _l: &mut [i32], _r: &mut [i32]) -> DecoderResult<()> { |
| 189 | unreachable!(); |
| 190 | } |
| 191 | |
| 192 | fn new_k(val: u32) -> u8 { |
| 193 | (32 - (val | 1).leading_zeros()) as u8 |
| 194 | } |
| 195 | fn rice_limit(k: u8) -> u32 { if k > 0 { 1 << (k + 4) } else { 0 } } |
| 196 | fn decode_channel_0000(br: &mut BitReader, dst: &mut [i32]) -> DecoderResult<()> { |
| 197 | let (part01, part2) = dst.split_at_mut(64); |
| 198 | let (part0, part1) = part01.split_at_mut(5); |
| 199 | let mut pos = 0; |
| 200 | let mut last = [0u32; 64]; |
| 201 | let mut sum = 0; |
| 202 | for el in part0.iter_mut() { |
| 203 | let val = br.read_code(UintCodeType::Rice(10))?; |
| 204 | sum += val; |
| 205 | *el = to_signed(val); |
| 206 | last[pos] = val; |
| 207 | pos += 1; |
| 208 | } |
| 209 | if part1.is_empty() { |
| 210 | return Ok(()); |
| 211 | } |
| 212 | let mut k = new_k(sum / 10); |
| 213 | let mut w = 12; |
| 214 | for el in part1.iter_mut() { |
| 215 | let val = br.read_code(UintCodeType::Rice(k))?; |
| 216 | sum += val; |
| 217 | *el = to_signed(val); |
| 218 | k = new_k(sum / w); |
| 219 | w += 2; |
| 220 | last[pos] = val; |
| 221 | pos += 1; |
| 222 | } |
| 223 | if part2.is_empty() { |
| 224 | return Ok(()); |
| 225 | } |
| 226 | let mut top_limit = rice_limit(k + 1) * 4; |
| 227 | let mut bot_limit = rice_limit(k) * 4; |
| 228 | pos = 0; |
| 229 | for el in part2.iter_mut() { |
| 230 | let val = br.read_code(UintCodeType::Rice(k))?; |
| 231 | *el = to_signed(val); |
| 232 | |
| 233 | sum = sum.wrapping_add(val.wrapping_sub(last[pos])); |
| 234 | while sum < bot_limit { |
| 235 | k -= 1; |
| 236 | bot_limit = rice_limit(k) * 4; |
| 237 | top_limit >>= 1; |
| 238 | } |
| 239 | while sum >= top_limit { |
| 240 | k += 1; |
| 241 | validate!(k < 24); |
| 242 | bot_limit = rice_limit(k) * 4; |
| 243 | top_limit <<= 1; |
| 244 | } |
| 245 | |
| 246 | last[pos] = val; |
| 247 | pos = (pos + 1) & 63; |
| 248 | } |
| 249 | |
| 250 | Ok(()) |
| 251 | } |
| 252 | pub fn decode_mono_0000(c: &mut Coder, l: &mut [i32]) -> DecoderResult<()> { |
| 253 | if let Coder::Rice(ref mut rr) = c { |
| 254 | decode_channel_0000(&mut rr.br, l) |
| 255 | } else { |
| 256 | Err(DecoderError::Bug) |
| 257 | } |
| 258 | } |
| 259 | pub fn decode_stereo_0000(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 260 | if let Coder::Rice(ref mut rr) = c { |
| 261 | decode_channel_0000(&mut rr.br, l)?; |
| 262 | decode_channel_0000(&mut rr.br, r)?; |
| 263 | Ok(()) |
| 264 | } else { |
| 265 | Err(DecoderError::Bug) |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | fn decode_value_3860(br: &mut BitReader, rice: &mut RiceParams) -> DecoderResult<i32> { |
| 270 | let overflow = br.read_code(UintCodeType::UnaryZeroes)?; |
| 271 | |
| 272 | let val = (overflow << rice.k) | br.read(rice.k)?; |
| 273 | rice.update_old(val); |
| 274 | Ok(to_signed(val)) |
| 275 | } |
| 276 | fn decode_value_3890(br: &mut BitReader, rice: &mut RiceParams) -> DecoderResult<i32> { |
| 277 | let mut overflow = br.read_code(UintCodeType::UnaryZeroes)?; |
| 278 | while overflow >= 16 { |
| 279 | overflow -= 16; |
| 280 | rice.k += 4; |
| 281 | } |
| 282 | |
| 283 | let val = (overflow << rice.k) | br.read(rice.k)?; |
| 284 | rice.update_old(val); |
| 285 | Ok(to_signed(val)) |
| 286 | } |
| 287 | pub fn decode_mono_3860(c: &mut Coder, l: &mut [i32]) -> DecoderResult<()> { |
| 288 | if let Coder::Rice(ref mut rr) = c { |
| 289 | for el in l.iter_mut() { |
| 290 | *el = decode_value_3860(&mut rr.br, &mut rr.rice_y)?; |
| 291 | } |
| 292 | Ok(()) |
| 293 | } else { |
| 294 | Err(DecoderError::Bug) |
| 295 | } |
| 296 | } |
| 297 | pub fn decode_mono_3890(c: &mut Coder, l: &mut [i32]) -> DecoderResult<()> { |
| 298 | if let Coder::Rice(ref mut rr) = c { |
| 299 | for el in l.iter_mut() { |
| 300 | *el = decode_value_3860(&mut rr.br, &mut rr.rice_y)?; |
| 301 | } |
| 302 | Ok(()) |
| 303 | } else { |
| 304 | Err(DecoderError::Bug) |
| 305 | } |
| 306 | } |
| 307 | pub fn decode_stereo_3860(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 308 | if let Coder::Rice(ref mut rr) = c { |
| 309 | for el in l.iter_mut() { |
| 310 | *el = decode_value_3860(&mut rr.br, &mut rr.rice_y)?; |
| 311 | } |
| 312 | for el in r.iter_mut() { |
| 313 | *el = decode_value_3860(&mut rr.br, &mut rr.rice_x)?; |
| 314 | } |
| 315 | Ok(()) |
| 316 | } else { |
| 317 | Err(DecoderError::Bug) |
| 318 | } |
| 319 | } |
| 320 | pub fn decode_stereo_3890(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 321 | if let Coder::Rice(ref mut rr) = c { |
| 322 | for el in l.iter_mut() { |
| 323 | *el = decode_value_3890(&mut rr.br, &mut rr.rice_y)?; |
| 324 | } |
| 325 | for el in r.iter_mut() { |
| 326 | *el = decode_value_3890(&mut rr.br, &mut rr.rice_x)?; |
| 327 | } |
| 328 | Ok(()) |
| 329 | } else { |
| 330 | Err(DecoderError::Bug) |
| 331 | } |
| 332 | } |
| 333 | |
| 334 | const COUNTS_3900: &[u32; 22] = &[ |
| 335 | 0, 14824, 28224, 39348, 47855, 53994, 58171, 60926, |
| 336 | 62682, 63786, 64463, 64878, 65126, 65276, 65365, 65419, |
| 337 | 65450, 65469, 65480, 65487, 65491, 65493 |
| 338 | ]; |
| 339 | fn decode_value_3900(rc: &mut ARangeCoder, rice: &mut RiceParams) -> i32 { |
| 340 | let mut overflow = rc.decode_symbol(COUNTS_3900); |
| 341 | let k = if overflow == MAX_MODEL_VAL { |
| 342 | overflow = 0; |
| 343 | rc.decode_bits(5) as u8 |
| 344 | } else { |
| 345 | rice.k.saturating_sub(1) |
| 346 | }; |
| 347 | let base = rc.decode_bits(k); |
| 348 | let val = base + (overflow << k); |
| 349 | rice.update(val); |
| 350 | to_signed(val) |
| 351 | } |
| 352 | fn decode_value_3910(rc: &mut ARangeCoder, rice: &mut RiceParams) -> i32 { |
| 353 | let mut overflow = rc.decode_symbol(COUNTS_3900); |
| 354 | let k = if overflow == MAX_MODEL_VAL { |
| 355 | overflow = 0; |
| 356 | rc.decode_bits(5) as u8 |
| 357 | } else { |
| 358 | rice.k.saturating_sub(1) |
| 359 | }; |
| 360 | let base = if k <= 16 { |
| 361 | rc.decode_bits(k) |
| 362 | } else if k <= 32 { |
| 363 | let low = rc.decode_bits(16); |
| 364 | let high = rc.decode_bits(k - 16); |
| 365 | (high << 16) | low |
| 366 | } else { |
| 367 | rc.error = true; |
| 368 | return 0; |
| 369 | }; |
| 370 | let val = base + (overflow << k); |
| 371 | rice.update(val); |
| 372 | to_signed(val) |
| 373 | } |
| 374 | pub fn decode_mono_3900(c: &mut Coder, l: &mut [i32]) -> DecoderResult<()> { |
| 375 | if let Coder::Range(ref mut rc) = c { |
| 376 | for el in l.iter_mut() { |
| 377 | *el = decode_value_3900(&mut rc.rc, &mut rc.rice_y); |
| 378 | } |
| 379 | validate!(!rc.had_errors()); |
| 380 | Ok(()) |
| 381 | } else { |
| 382 | Err(DecoderError::Bug) |
| 383 | } |
| 384 | } |
| 385 | pub fn decode_mono_3910(c: &mut Coder, l: &mut [i32]) -> DecoderResult<()> { |
| 386 | if let Coder::Range(ref mut rc) = c { |
| 387 | for el in l.iter_mut() { |
| 388 | *el = decode_value_3910(&mut rc.rc, &mut rc.rice_y); |
| 389 | } |
| 390 | validate!(!rc.had_errors()); |
| 391 | Ok(()) |
| 392 | } else { |
| 393 | Err(DecoderError::Bug) |
| 394 | } |
| 395 | } |
| 396 | pub fn decode_stereo_3900(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 397 | if let Coder::Range(ref mut rc) = c { |
| 398 | for el in l.iter_mut() { |
| 399 | *el = decode_value_3900(&mut rc.rc, &mut rc.rice_y); |
| 400 | } |
| 401 | rc.rc.normalise(); |
| 402 | validate!(!rc.had_errors() && rc.rc.pos < rc.rc.src.len()); |
| 403 | rc.rc.reset(); |
| 404 | for el in r.iter_mut() { |
| 405 | *el = decode_value_3900(&mut rc.rc, &mut rc.rice_x); |
| 406 | } |
| 407 | validate!(!rc.had_errors()); |
| 408 | Ok(()) |
| 409 | } else { |
| 410 | Err(DecoderError::Bug) |
| 411 | } |
| 412 | } |
| 413 | pub fn decode_stereo_3910(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 414 | if let Coder::Range(ref mut rc) = c { |
| 415 | for el in l.iter_mut() { |
| 416 | *el = decode_value_3910(&mut rc.rc, &mut rc.rice_y); |
| 417 | } |
| 418 | rc.rc.normalise(); |
| 419 | validate!(!rc.had_errors() && rc.rc.pos < rc.rc.src.len()); |
| 420 | rc.rc.reset(); |
| 421 | for el in r.iter_mut() { |
| 422 | *el = decode_value_3910(&mut rc.rc, &mut rc.rice_x); |
| 423 | } |
| 424 | validate!(!rc.had_errors()); |
| 425 | Ok(()) |
| 426 | } else { |
| 427 | Err(DecoderError::Bug) |
| 428 | } |
| 429 | } |
| 430 | pub fn decode_stereo_3930(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 431 | if let Coder::Range(ref mut rc) = c { |
| 432 | for (l, r) in l.iter_mut().zip(r.iter_mut()) { |
| 433 | *l = decode_value_3910(&mut rc.rc, &mut rc.rice_y); |
| 434 | *r = decode_value_3910(&mut rc.rc, &mut rc.rice_x); |
| 435 | } |
| 436 | validate!(!rc.had_errors()); |
| 437 | Ok(()) |
| 438 | } else { |
| 439 | Err(DecoderError::Bug) |
| 440 | } |
| 441 | } |
| 442 | |
| 443 | const COUNTS_3990: &[u32; 22] = &[ |
| 444 | 0, 19578, 36160, 48417, 56323, 60899, 63265, 64435, |
| 445 | 64971, 65232, 65351, 65416, 65447, 65466, 65476, 65482, |
| 446 | 65485, 65488, 65490, 65491, 65492, 65493 |
| 447 | ]; |
| 448 | fn decode_value_3990(rc: &mut ARangeCoder, rice: &mut RiceParams) -> i32 { |
| 449 | let pivot = (rice.sum >> 5).max(1); |
| 450 | let mut overflow = rc.decode_symbol(COUNTS_3990); |
| 451 | if overflow == MAX_MODEL_VAL { |
| 452 | overflow = rc.decode_bits(16) << 16; |
| 453 | overflow |= rc.decode_bits(16); |
| 454 | } |
| 455 | let base = if pivot < (1 << 16) { |
| 456 | rc.decode_freq(pivot) |
| 457 | } else { |
| 458 | let shift = (16 - pivot.trailing_zeros()) as u8; |
| 459 | let hi = rc.decode_freq((pivot >> shift) + 1); |
| 460 | let lo = rc.decode_bits(shift); |
| 461 | (hi << shift) | lo |
| 462 | }; |
| 463 | let val = base + overflow * pivot; |
| 464 | rice.update(val); |
| 465 | to_signed(val) |
| 466 | } |
| 467 | pub fn decode_mono_3990(c: &mut Coder, l: &mut [i32]) -> DecoderResult<()> { |
| 468 | if let Coder::Range(ref mut rc) = c { |
| 469 | for el in l.iter_mut() { |
| 470 | *el = decode_value_3990(&mut rc.rc, &mut rc.rice_y); |
| 471 | } |
| 472 | validate!(!rc.had_errors()); |
| 473 | Ok(()) |
| 474 | } else { |
| 475 | Err(DecoderError::Bug) |
| 476 | } |
| 477 | } |
| 478 | pub fn decode_stereo_3990(c: &mut Coder, l: &mut [i32], r: &mut [i32]) -> DecoderResult<()> { |
| 479 | if let Coder::Range(ref mut rc) = c { |
| 480 | for (l, r) in l.iter_mut().zip(r.iter_mut()) { |
| 481 | *l = decode_value_3990(&mut rc.rc, &mut rc.rice_y); |
| 482 | *r = decode_value_3990(&mut rc.rc, &mut rc.rice_x); |
| 483 | } |
| 484 | validate!(!rc.had_errors()); |
| 485 | Ok(()) |
| 486 | } else { |
| 487 | Err(DecoderError::Bug) |
| 488 | } |
| 489 | } |