| 1 | //use nihav_core::codecs::{DecoderResult, DecoderError}; |
| 2 | |
| 3 | use super::*; |
| 4 | use super::cabac_coder::*; |
| 5 | use super::dsp::{CHROMA_DC_SCAN, ZIGZAG, ZIGZAG1, ZIGZAG8X8}; |
| 6 | use super::slice::SliceHeader; |
| 7 | |
| 8 | pub fn cabac_decode_mbskip(cabac: &mut CABAC, sstate: &SliceState, slice_hdr: &SliceHeader) -> bool { |
| 9 | let skip_idx = if slice_hdr.slice_type.is_p() { 11 } else { 24 }; |
| 10 | let mut mb_skip_ctx = 0; |
| 11 | let left_mbt = sstate.get_left_mb().mb_type; |
| 12 | let top_mbt = sstate.get_top_mb().mb_type; |
| 13 | if left_mbt != CompactMBType::None && !left_mbt.is_skip() { |
| 14 | mb_skip_ctx += 1; |
| 15 | } |
| 16 | if top_mbt != CompactMBType::None && !top_mbt.is_skip() { |
| 17 | mb_skip_ctx += 1; |
| 18 | } |
| 19 | if !slice_hdr.slice_type.is_intra() { |
| 20 | cabac.decode_bit(skip_idx + mb_skip_ctx) |
| 21 | } else { |
| 22 | false |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | fn decode_i_type(cabac: &mut CABAC, start: usize, ctx: usize) -> MBType { |
| 27 | if !cabac.decode_bit(start + ctx) { |
| 28 | MBType::Intra4x4 |
| 29 | } else if !cabac.decode_terminate() { |
| 30 | let cbpy = if cabac.decode_bit(start + 3) { 0xF } else { 0x0 }; |
| 31 | let cbpc = cabac.decode_012(start + 4); |
| 32 | let ipred = cabac.decode_bits(start + 6, start + 7, 2); |
| 33 | |
| 34 | MBType::Intra16x16(ipred, cbpy, cbpc) |
| 35 | } else { |
| 36 | MBType::PCM |
| 37 | } |
| 38 | } |
| 39 | |
| 40 | fn decode_i_type_inter(cabac: &mut CABAC, start: usize) -> MBType { |
| 41 | if !cabac.decode_bit(start) { |
| 42 | MBType::Intra4x4 |
| 43 | } else if !cabac.decode_terminate() { |
| 44 | let cbpy = if cabac.decode_bit(start + 1) { 0xF } else { 0x0 }; |
| 45 | let cbpc = if !cabac.decode_bit(start + 2) { |
| 46 | 0 |
| 47 | } else if !cabac.decode_bit(start + 2) { |
| 48 | 1 |
| 49 | } else { |
| 50 | 2 |
| 51 | }; |
| 52 | let ipred = cabac.decode_bits(start + 3, start + 3, 2); |
| 53 | |
| 54 | MBType::Intra16x16(ipred, cbpy, cbpc) |
| 55 | } else { |
| 56 | MBType::PCM |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | fn remap_si_mbtype(mbtype: MBType) -> MBType { |
| 61 | match mbtype { |
| 62 | MBType::Intra16x16(0, 0, 0) => MBType::Intra4x4, |
| 63 | MBType::Intra16x16(imode, cbpy, cbpc) => { |
| 64 | let idx = imode + if cbpy != 0 { 12 } else { 0 } + cbpc * 4 - 1; |
| 65 | let nimode = idx & 3; |
| 66 | let (ncbpy, ncbpc) = if (idx >> 2) >= 3 { |
| 67 | (0xF, (idx >> 2) - 3) |
| 68 | } else { |
| 69 | (0x0, idx >> 2) |
| 70 | }; |
| 71 | MBType::Intra16x16(nimode, ncbpy, ncbpc) |
| 72 | }, |
| 73 | MBType::PCM => MBType::Intra16x16(3, 1, 2), |
| 74 | _ => mbtype, |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | pub fn cabac_decode_mb_type(cabac: &mut CABAC, slice_hdr: &SliceHeader, sstate: &SliceState) -> MBType { |
| 79 | match slice_hdr.slice_type { |
| 80 | SliceType::I | SliceType::SI => { |
| 81 | let mut ctx = 0; |
| 82 | if sstate.get_left_mb().mb_type.is_intra16orpcm() { |
| 83 | ctx += 1; |
| 84 | } |
| 85 | if sstate.get_top_mb().mb_type.is_intra16orpcm() { |
| 86 | ctx += 1; |
| 87 | } |
| 88 | let mbtype = decode_i_type(cabac, 3, ctx); |
| 89 | if slice_hdr.slice_type == SliceType::I { |
| 90 | mbtype |
| 91 | } else { |
| 92 | remap_si_mbtype(mbtype) |
| 93 | } |
| 94 | }, |
| 95 | SliceType::P | SliceType::SP => { |
| 96 | if cabac.decode_bit(14) { |
| 97 | decode_i_type_inter(cabac, 17) |
| 98 | } else if !cabac.decode_bit(15) { |
| 99 | if !cabac.decode_bit(16) { |
| 100 | MBType::P16x16 |
| 101 | } else { |
| 102 | MBType::P8x8 |
| 103 | } |
| 104 | } else { |
| 105 | if !cabac.decode_bit(17) { |
| 106 | MBType::P8x16 |
| 107 | } else { |
| 108 | MBType::P16x8 |
| 109 | } |
| 110 | } |
| 111 | }, |
| 112 | SliceType::B => { |
| 113 | let mut ctx = 0; |
| 114 | if !sstate.get_left_mb().mb_type.is_direct() { |
| 115 | ctx += 1; |
| 116 | } |
| 117 | if !sstate.get_top_mb().mb_type.is_direct() { |
| 118 | ctx += 1; |
| 119 | } |
| 120 | if !cabac.decode_bit(27 + ctx) { |
| 121 | MBType::Direct |
| 122 | } else if !cabac.decode_bit(30) { |
| 123 | if !cabac.decode_bit(32) { |
| 124 | MBType::B16x16(BMode::L0) |
| 125 | } else { |
| 126 | MBType::B16x16(BMode::L1) |
| 127 | } |
| 128 | } else { |
| 129 | let idx = cabac.decode_bits(31, 32, 4); |
| 130 | match idx { |
| 131 | 0x0 => MBType::B16x16(BMode::Bi), |
| 132 | 0x1 => MBType::B16x8(BMode::L0, BMode::L0), |
| 133 | 0x2 => MBType::B8x16(BMode::L0, BMode::L0), |
| 134 | 0x3 => MBType::B16x8(BMode::L1, BMode::L1), |
| 135 | 0x4 => MBType::B8x16(BMode::L1, BMode::L1), |
| 136 | 0x5 => MBType::B16x8(BMode::L0, BMode::L1), |
| 137 | 0x6 => MBType::B8x16(BMode::L0, BMode::L1), |
| 138 | 0x7 => MBType::B16x8(BMode::L1, BMode::L0), |
| 139 | 0xE => MBType::B8x16(BMode::L1, BMode::L0), |
| 140 | 0xF => MBType::B8x8, |
| 141 | 0xD => decode_i_type_inter(cabac, 32), |
| 142 | _ => { |
| 143 | let idx = (idx - 8) * 2 + (cabac.decode_bit(32) as u8); |
| 144 | match idx { |
| 145 | 0 => MBType::B16x8(BMode::L0, BMode::Bi), |
| 146 | 1 => MBType::B8x16(BMode::L0, BMode::Bi), |
| 147 | 2 => MBType::B16x8(BMode::L1, BMode::Bi), |
| 148 | 3 => MBType::B8x16(BMode::L1, BMode::Bi), |
| 149 | 4 => MBType::B16x8(BMode::Bi, BMode::L0), |
| 150 | 5 => MBType::B8x16(BMode::Bi, BMode::L0), |
| 151 | 6 => MBType::B16x8(BMode::Bi, BMode::L1), |
| 152 | 7 => MBType::B8x16(BMode::Bi, BMode::L1), |
| 153 | 8 => MBType::B16x8(BMode::Bi, BMode::Bi), |
| 154 | _ => MBType::B8x16(BMode::Bi, BMode::Bi), |
| 155 | } |
| 156 | }, |
| 157 | } |
| 158 | } |
| 159 | }, |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | fn decode_sub_mb_type_cabac(cabac: &mut CABAC, slice_hdr: &SliceHeader) -> SubMBType { |
| 164 | match slice_hdr.slice_type { |
| 165 | SliceType::P | SliceType::SP => { |
| 166 | if cabac.decode_bit(21) { |
| 167 | SubMBType::P8x8 |
| 168 | } else if !cabac.decode_bit(22) { |
| 169 | SubMBType::P8x4 |
| 170 | } else if cabac.decode_bit(23) { |
| 171 | SubMBType::P4x8 |
| 172 | } else { |
| 173 | SubMBType::P4x4 |
| 174 | } |
| 175 | }, |
| 176 | SliceType::B => { |
| 177 | if !cabac.decode_bit(36) { |
| 178 | SubMBType::Direct8x8 |
| 179 | } else if !cabac.decode_bit(37) { |
| 180 | if !cabac.decode_bit(39) { |
| 181 | SubMBType::B8x8(BMode::L0) |
| 182 | } else { |
| 183 | SubMBType::B8x8(BMode::L1) |
| 184 | } |
| 185 | } else { |
| 186 | let idx = cabac.decode_bits(38, 39, 3); |
| 187 | match idx { |
| 188 | 0 => SubMBType::B8x8(BMode::Bi), |
| 189 | 1 => SubMBType::B8x4(BMode::L0), |
| 190 | 2 => SubMBType::B4x8(BMode::L0), |
| 191 | 3 => SubMBType::B8x4(BMode::L1), |
| 192 | 6 => SubMBType::B4x4(BMode::L1), |
| 193 | 7 => SubMBType::B4x4(BMode::Bi), |
| 194 | _ => { |
| 195 | let idx = (idx - 4) * 2 + (cabac.decode_bit(39) as u8); |
| 196 | match idx { |
| 197 | 0 => SubMBType::B4x8(BMode::L1), |
| 198 | 1 => SubMBType::B8x4(BMode::Bi), |
| 199 | 2 => SubMBType::B4x8(BMode::Bi), |
| 200 | _ => SubMBType::B4x4(BMode::L0), |
| 201 | } |
| 202 | }, |
| 203 | } |
| 204 | } |
| 205 | }, |
| 206 | _ => unreachable!(), |
| 207 | } |
| 208 | } |
| 209 | |
| 210 | fn decode_ref_idx(cabac: &mut CABAC, num_refs: usize, ctx: usize) -> PicRef { |
| 211 | if num_refs == 1 { |
| 212 | return ZERO_REF; |
| 213 | } |
| 214 | if !cabac.decode_bit(54 + ctx) { |
| 215 | ZERO_REF |
| 216 | } else if !cabac.decode_bit(54 + 4) { |
| 217 | PicRef::new(1) |
| 218 | } else { |
| 219 | let mut idx = 2; |
| 220 | while cabac.decode_bit(54 + 5) && idx < 32 { |
| 221 | idx += 1; |
| 222 | } |
| 223 | if idx < num_refs { |
| 224 | PicRef::new(idx as u8) |
| 225 | } else { |
| 226 | INVALID_REF |
| 227 | } |
| 228 | } |
| 229 | } |
| 230 | |
| 231 | fn decode_mv_component(cabac: &mut CABAC, base: usize, ctx: usize) -> i16 { |
| 232 | if !cabac.decode_bit(base + ctx) { |
| 233 | 0 |
| 234 | } else { |
| 235 | let mut val = 1; |
| 236 | while val < 9 && cabac.decode_bit(base + (2 + val).min(6)) { |
| 237 | val += 1; |
| 238 | } |
| 239 | if val >= 9 { |
| 240 | let mut pfx = 3; |
| 241 | while pfx < 16 && cabac.decode_bypass() { |
| 242 | val += 1 << pfx; |
| 243 | pfx += 1; |
| 244 | } |
| 245 | val += cabac.decode_bypass_bits(pfx) as usize; |
| 246 | } |
| 247 | if val == 0 || !cabac.decode_bypass() { |
| 248 | val as i16 |
| 249 | } else { |
| 250 | -(val as i16) |
| 251 | } |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | fn decode_mv(cabac: &mut CABAC, ctx0: usize, ctx1: usize) -> MV { |
| 256 | let x = decode_mv_component(cabac, 40, ctx0); |
| 257 | let y = decode_mv_component(cabac, 47, ctx1); |
| 258 | MV{ x, y } |
| 259 | } |
| 260 | |
| 261 | #[allow(clippy::cognitive_complexity)] |
| 262 | pub fn decode_mb_pred_cabac(cabac: &mut CABAC, slice_hdr: &SliceHeader, mb_type: MBType, sstate: &mut SliceState, mb_info: &mut CurrentMBInfo) { |
| 263 | mb_info.mb_type = mb_type; |
| 264 | let num_l0 = slice_hdr.num_ref_idx_l0_active; |
| 265 | let num_l1 = slice_hdr.num_ref_idx_l1_active; |
| 266 | sstate.reset_mb_mv(); |
| 267 | match mb_type { |
| 268 | MBType::Intra4x4 => { |
| 269 | for &(x, y) in I4X4_SCAN.iter() { |
| 270 | let x = x as usize; |
| 271 | let y = y as usize; |
| 272 | let top_pred = sstate.get_top_blk4(x + y * 4).ipred; |
| 273 | let left_pred = sstate.get_left_blk4(x + y * 4).ipred; |
| 274 | |
| 275 | let top_idx = top_pred.into_pred_idx(); |
| 276 | let left_idx = left_pred.into_pred_idx(); |
| 277 | let pred_mode = top_idx.min(left_idx); |
| 278 | let mut pred_mode = if pred_mode != -1 { pred_mode as u8 } else { 2 }; |
| 279 | |
| 280 | if !cabac.decode_bit(68) { |
| 281 | let m0 = cabac.decode_bit(69) as u8; |
| 282 | let m1 = cabac.decode_bit(69) as u8; |
| 283 | let m2 = cabac.decode_bit(69) as u8; |
| 284 | let new_mode = (m2 << 2) | (m1 << 1) | m0; |
| 285 | pred_mode = if new_mode >= pred_mode { |
| 286 | new_mode + 1 |
| 287 | } else { new_mode }; |
| 288 | } |
| 289 | mb_info.ipred[x + y * 4] = pred_mode.into(); |
| 290 | sstate.get_cur_blk4(x + y * 4).ipred = (pred_mode as u8).into(); |
| 291 | } |
| 292 | let mut ctx = 0; |
| 293 | if sstate.get_left_mb().cmode != 0 { |
| 294 | ctx += 1; |
| 295 | } |
| 296 | if sstate.get_top_mb().cmode != 0 { |
| 297 | ctx += 1; |
| 298 | } |
| 299 | mb_info.chroma_ipred = if !cabac.decode_bit(64 + ctx) { |
| 300 | 0 |
| 301 | } else if !cabac.decode_bit(67) { |
| 302 | 1 |
| 303 | } else if !cabac.decode_bit(67) { |
| 304 | 2 |
| 305 | } else { |
| 306 | 3 |
| 307 | }; |
| 308 | }, |
| 309 | MBType::Intra8x8 => { |
| 310 | for part in 0..4 { |
| 311 | let blk4 = (part & 1) * 2 + (part & 2) * 4; |
| 312 | let top_pred = sstate.get_top_blk4(blk4).ipred; |
| 313 | let left_pred = sstate.get_left_blk4(blk4).ipred; |
| 314 | |
| 315 | let top_idx = top_pred.into_pred_idx(); |
| 316 | let left_idx = left_pred.into_pred_idx(); |
| 317 | let pred_mode = top_idx.min(left_idx); |
| 318 | let mut pred_mode = if pred_mode != -1 { pred_mode as u8 } else { 2 }; |
| 319 | if !cabac.decode_bit(68) { |
| 320 | let m0 = cabac.decode_bit(69) as u8; |
| 321 | let m1 = cabac.decode_bit(69) as u8; |
| 322 | let m2 = cabac.decode_bit(69) as u8; |
| 323 | let new_mode = (m2 << 2) | (m1 << 1) | m0; |
| 324 | pred_mode = if new_mode >= pred_mode { |
| 325 | new_mode + 1 |
| 326 | } else { new_mode }; |
| 327 | } |
| 328 | mb_info.ipred[blk4] = pred_mode.into(); |
| 329 | mb_info.ipred[blk4 + 1] = pred_mode.into(); |
| 330 | mb_info.ipred[blk4 + 4] = pred_mode.into(); |
| 331 | mb_info.ipred[blk4 + 5] = pred_mode.into(); |
| 332 | sstate.get_cur_blk4(blk4).ipred = (pred_mode as u8).into(); |
| 333 | sstate.get_cur_blk4(blk4 + 1).ipred = (pred_mode as u8).into(); |
| 334 | sstate.get_cur_blk4(blk4 + 4).ipred = (pred_mode as u8).into(); |
| 335 | sstate.get_cur_blk4(blk4 + 5).ipred = (pred_mode as u8).into(); |
| 336 | } |
| 337 | let mut ctx = 0; |
| 338 | if sstate.get_left_mb().cmode != 0 { |
| 339 | ctx += 1; |
| 340 | } |
| 341 | if sstate.get_top_mb().cmode != 0 { |
| 342 | ctx += 1; |
| 343 | } |
| 344 | mb_info.chroma_ipred = if !cabac.decode_bit(64 + ctx) { |
| 345 | 0 |
| 346 | } else if !cabac.decode_bit(67) { |
| 347 | 1 |
| 348 | } else if !cabac.decode_bit(67) { |
| 349 | 2 |
| 350 | } else { |
| 351 | 3 |
| 352 | }; |
| 353 | }, |
| 354 | MBType::Intra16x16(_ipred, _, _) => { |
| 355 | let mut ctx = 0; |
| 356 | if sstate.get_left_mb().cmode != 0 { |
| 357 | ctx += 1; |
| 358 | } |
| 359 | if sstate.get_top_mb().cmode != 0 { |
| 360 | ctx += 1; |
| 361 | } |
| 362 | mb_info.chroma_ipred = if !cabac.decode_bit(64 + ctx) { |
| 363 | 0 |
| 364 | } else if !cabac.decode_bit(67) { |
| 365 | 1 |
| 366 | } else if !cabac.decode_bit(67) { |
| 367 | 2 |
| 368 | } else { |
| 369 | 3 |
| 370 | }; |
| 371 | }, |
| 372 | MBType::P16x16 | MBType::P16x8 | MBType::P8x16 => { |
| 373 | let num_subparts = mb_type.num_parts(); |
| 374 | let (pw, ph) = mb_type.size(); |
| 375 | let mut xoff = 0; |
| 376 | let mut yoff = 0; |
| 377 | for i in 0..num_subparts { |
| 378 | let ctx = sstate.get_mv_ref_ctx(xoff, yoff, 0); |
| 379 | let ref_idx = decode_ref_idx(cabac, num_l0, ctx); |
| 380 | mb_info.ref_l0[i] = ref_idx; |
| 381 | sstate.fill_ref(xoff, yoff, pw, ph, 0, ref_idx); |
| 382 | xoff += pw; |
| 383 | if xoff == 16 { |
| 384 | xoff = 0; |
| 385 | yoff += ph; |
| 386 | } |
| 387 | } |
| 388 | let mut xoff = 0; |
| 389 | let mut yoff = 0; |
| 390 | for i in 0..num_subparts { |
| 391 | let (ctx0, ctx1) = sstate.get_mv_ctx(xoff, yoff, 0); |
| 392 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 393 | mb_info.mv_l0[i] = mv; |
| 394 | sstate.fill_mvd(xoff, yoff, pw, ph, 0, mv); |
| 395 | xoff += pw; |
| 396 | if xoff == 16 { |
| 397 | xoff = 0; |
| 398 | yoff += ph; |
| 399 | } |
| 400 | } |
| 401 | }, |
| 402 | MBType::B16x16(mode) => { |
| 403 | if mode != BMode::L1 { |
| 404 | let ctx = sstate.get_mv_ref_ctx(0, 0, 0); |
| 405 | let ref_idx = decode_ref_idx(cabac, num_l0, ctx); |
| 406 | mb_info.ref_l0[0] = ref_idx; |
| 407 | sstate.fill_ref(0, 0, 16, 16, 0, ref_idx); |
| 408 | } |
| 409 | if mode != BMode::L0 { |
| 410 | let ctx = sstate.get_mv_ref_ctx(0, 0, 1); |
| 411 | let ref_idx = decode_ref_idx(cabac, num_l1, ctx); |
| 412 | mb_info.ref_l1[0] = ref_idx; |
| 413 | sstate.fill_ref(0, 0, 16, 16, 1, ref_idx); |
| 414 | } |
| 415 | if mode != BMode::L1 { |
| 416 | let (ctx0, ctx1) = sstate.get_mv_ctx(0, 0, 0); |
| 417 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 418 | mb_info.mv_l0[0] = mv; |
| 419 | sstate.fill_mvd(0, 0, 16, 16, 0, mv); |
| 420 | } |
| 421 | if mode != BMode::L0 { |
| 422 | let (ctx0, ctx1) = sstate.get_mv_ctx(0, 0, 1); |
| 423 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 424 | mb_info.mv_l1[0] = mv; |
| 425 | sstate.fill_mvd(0, 0, 16, 16, 1, mv); |
| 426 | } |
| 427 | }, |
| 428 | MBType::B16x8(mode0, mode1) | MBType::B8x16(mode0, mode1) => { |
| 429 | let (pw, ph) = mb_info.mb_type.size(); |
| 430 | let (px, py) = (pw & 8, ph & 8); |
| 431 | if mode0 != BMode::L1 { |
| 432 | let ctx = sstate.get_mv_ref_ctx(0, 0, 0); |
| 433 | let ref_idx = decode_ref_idx(cabac, num_l0, ctx); |
| 434 | mb_info.ref_l0[0] = ref_idx; |
| 435 | sstate.fill_ref(0, 0, pw, ph, 0, ref_idx); |
| 436 | } |
| 437 | if mode1 != BMode::L1 { |
| 438 | let ctx = sstate.get_mv_ref_ctx(pw & 8, ph & 8, 0); |
| 439 | let ref_idx = decode_ref_idx(cabac, num_l0, ctx); |
| 440 | mb_info.ref_l0[1] = ref_idx; |
| 441 | sstate.fill_ref(px, py, pw, ph, 0, ref_idx); |
| 442 | } |
| 443 | if mode0 != BMode::L0 { |
| 444 | let ctx = sstate.get_mv_ref_ctx(0, 0, 1); |
| 445 | let ref_idx = decode_ref_idx(cabac, num_l1, ctx); |
| 446 | mb_info.ref_l1[0] = ref_idx; |
| 447 | sstate.fill_ref(0, 0, pw, ph, 1, ref_idx); |
| 448 | } |
| 449 | if mode1 != BMode::L0 { |
| 450 | let ctx = sstate.get_mv_ref_ctx(pw & 8, ph & 8, 1); |
| 451 | let ref_idx = decode_ref_idx(cabac, num_l1, ctx); |
| 452 | mb_info.ref_l1[1] = ref_idx; |
| 453 | sstate.fill_ref(px, py, pw, ph, 1, ref_idx); |
| 454 | } |
| 455 | if mode0 != BMode::L1 { |
| 456 | let (ctx0, ctx1) = sstate.get_mv_ctx(0, 0, 0); |
| 457 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 458 | mb_info.mv_l0[0] = mv; |
| 459 | sstate.fill_mvd(0, 0, pw, ph, 0, mv); |
| 460 | } |
| 461 | if mode1 != BMode::L1 { |
| 462 | let (ctx0, ctx1) = sstate.get_mv_ctx(pw & 8, ph & 8, 0); |
| 463 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 464 | mb_info.mv_l0[1] = mv; |
| 465 | sstate.fill_mvd(px, py, pw, ph, 0, mv); |
| 466 | } |
| 467 | if mode0 != BMode::L0 { |
| 468 | let (ctx0, ctx1) = sstate.get_mv_ctx(0, 0, 1); |
| 469 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 470 | mb_info.mv_l1[0] = mv; |
| 471 | sstate.fill_mvd(0, 0, pw, ph, 1, mv); |
| 472 | } |
| 473 | if mode1 != BMode::L0 { |
| 474 | let (ctx0, ctx1) = sstate.get_mv_ctx(pw & 8, ph & 8, 1); |
| 475 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 476 | mb_info.mv_l1[1] = mv; |
| 477 | sstate.fill_mvd(px, py, pw, ph, 1, mv); |
| 478 | } |
| 479 | }, |
| 480 | MBType::P8x8 | MBType::B8x8 => { |
| 481 | for sub_type in mb_info.sub_mb_type.iter_mut() { |
| 482 | *sub_type = decode_sub_mb_type_cabac(cabac, slice_hdr); |
| 483 | } |
| 484 | let num_l = [num_l0, num_l1]; |
| 485 | let dst_ref = [&mut mb_info.ref_l0, &mut mb_info.ref_l1]; |
| 486 | for ref_l in 0..2 { |
| 487 | for spart in 0..4 { |
| 488 | let stype = mb_info.sub_mb_type[spart]; |
| 489 | if stype != SubMBType::Direct8x8 && ((ref_l == 0 && !stype.is_l1()) || (ref_l == 1 && !stype.is_l0())) { |
| 490 | let ctx = sstate.get_mv_ref_ctx((spart & 1) * 8, (spart & 2) * 4, ref_l); |
| 491 | let ref_idx = decode_ref_idx(cabac, num_l[ref_l], ctx); |
| 492 | dst_ref[ref_l][spart] = ref_idx; |
| 493 | sstate.get_cur_blk8(spart).ref_idx[ref_l] = ref_idx; |
| 494 | } |
| 495 | } |
| 496 | } |
| 497 | let dst_mv = [&mut mb_info.mv_l0, &mut mb_info.mv_l1]; |
| 498 | for ref_l in 0..2 { |
| 499 | for spart in 0..4 { |
| 500 | let stype = mb_info.sub_mb_type[spart]; |
| 501 | if stype == SubMBType::Direct8x8 || (ref_l == 0 && stype.is_l1()) || (ref_l == 1 && stype.is_l0()) { |
| 502 | continue; |
| 503 | } |
| 504 | let (pw, ph) = stype.size(); |
| 505 | let mut xoff = (spart & 1) * 8; |
| 506 | let mut yoff = (spart & 2) * 4; |
| 507 | let num_sub = stype.num_parts(); |
| 508 | let orig_x = xoff; |
| 509 | for i in 0..num_sub { |
| 510 | let (ctx0, ctx1) = sstate.get_mv_ctx(xoff, yoff, ref_l); |
| 511 | let mv = decode_mv(cabac, ctx0, ctx1); |
| 512 | dst_mv[ref_l][spart * 4 + i] = mv; |
| 513 | sstate.fill_mvd(xoff, yoff, pw, ph, ref_l, mv); |
| 514 | xoff += pw; |
| 515 | if xoff == orig_x + 8 { |
| 516 | xoff -= 8; |
| 517 | yoff += ph; |
| 518 | } |
| 519 | } |
| 520 | } |
| 521 | } |
| 522 | }, |
| 523 | _ => {}, |
| 524 | }; |
| 525 | } |
| 526 | |
| 527 | pub fn decode_cbp_cabac(cabac: &mut CABAC, sstate: &SliceState) -> (u8, u8) { |
| 528 | let mbt_a = sstate.get_left_mb().mb_type; |
| 529 | let mbt_b = sstate.get_top_mb().mb_type; |
| 530 | let left = if mbt_a == CompactMBType::None || mbt_a == CompactMBType::PCM { |
| 531 | 0x3F |
| 532 | } else if !mbt_a.is_skip() { |
| 533 | sstate.get_left_mb().cbp |
| 534 | } else { |
| 535 | 0 |
| 536 | }; |
| 537 | let top = if mbt_b == CompactMBType::None || mbt_b == CompactMBType::PCM { |
| 538 | 0x3F |
| 539 | } else if !mbt_b.is_skip() { |
| 540 | sstate.get_top_mb().cbp |
| 541 | } else { |
| 542 | 0 |
| 543 | }; |
| 544 | |
| 545 | let cbp_ctx = if (left & 2) != 0 { 0 } else { 1 } + if (top & 4) != 0 { 0 } else { 2 }; |
| 546 | let mut cbpy = cabac.decode_bit(73 + cbp_ctx) as u8; |
| 547 | let cbp_ctx = if cbpy != 0 { 0 } else { 1 } + if (top & 8) != 0 { 0 } else { 2 }; |
| 548 | cbpy |= (cabac.decode_bit(73 + cbp_ctx) as u8) << 1; |
| 549 | let cbp_ctx = if (left & 8) != 0 { 0 } else { 1 } + if (cbpy & 1) != 0 { 0 } else { 2 }; |
| 550 | cbpy |= (cabac.decode_bit(73 + cbp_ctx) as u8) << 2; |
| 551 | let cbp_ctx = if (cbpy & 4) != 0 { 0 } else { 1 } + if (cbpy & 2) != 0 { 0 } else { 2 }; |
| 552 | cbpy |= (cabac.decode_bit(73 + cbp_ctx) as u8) << 3; |
| 553 | |
| 554 | let left = if mbt_a == CompactMBType::PCM { |
| 555 | 0x2F |
| 556 | } else if mbt_a == CompactMBType::None || !mbt_a.is_skip() { |
| 557 | sstate.get_left_mb().cbp |
| 558 | } else { |
| 559 | 0 |
| 560 | }; |
| 561 | let top = if mbt_b == CompactMBType::PCM { |
| 562 | 0x2F |
| 563 | } else if mbt_b == CompactMBType::None || !mbt_b.is_skip() { |
| 564 | sstate.get_top_mb().cbp |
| 565 | } else { |
| 566 | 0 |
| 567 | }; |
| 568 | let cleft = left >> 4; |
| 569 | let ctop = top >> 4; |
| 570 | let cbp_ctx0 = if cleft != 0 { 1 } else { 0 } + if ctop != 0 { 2 } else { 0 }; |
| 571 | let cbp_ctx1 = if cleft == 2 { 1 } else { 0 } + if ctop == 2 { 2 } else { 0 }; |
| 572 | let cbpc = if !cabac.decode_bit(77 + cbp_ctx0) { |
| 573 | 0 |
| 574 | } else { |
| 575 | cabac.decode_bit(81 + cbp_ctx1) as u8 + 1 |
| 576 | }; |
| 577 | |
| 578 | (cbpy, cbpc) |
| 579 | } |
| 580 | |
| 581 | pub fn decode_mb_qp_delta_cabac(cabac: &mut CABAC, ctx: usize) -> i32 { |
| 582 | if !cabac.decode_bit(60 + ctx) { |
| 583 | 0 |
| 584 | } else if !cabac.decode_bit(62) { |
| 585 | 1 |
| 586 | } else { |
| 587 | let mut val = 0; |
| 588 | while val < 128 && cabac.decode_bit(63) { |
| 589 | val += 1; |
| 590 | } |
| 591 | if (val & 1) != 0 { |
| 592 | ((val >> 1) as i32) + 2 |
| 593 | } else { |
| 594 | -((val >> 1) as i32) - 1 |
| 595 | } |
| 596 | } |
| 597 | } |
| 598 | |
| 599 | fn decode_block(cabac: &mut CABAC, coeffs: &mut [i16], cat: usize, ctx_off: usize) -> bool { |
| 600 | const CTX_BASE: [(usize, usize); 5] = [ |
| 601 | (0, 0), (15, 10), (29, 20), (44, 30), (47, 39) |
| 602 | ]; |
| 603 | let (flag_off, coef_off) = CTX_BASE[cat]; |
| 604 | let scan: &[usize] = match coeffs.len() { |
| 605 | 4 => &CHROMA_DC_SCAN, |
| 606 | 15 => &ZIGZAG1, |
| 607 | 16 => &ZIGZAG, |
| 608 | _ => unreachable!(), |
| 609 | }; |
| 610 | |
| 611 | let coded_block_flag = cabac.decode_bit(85 + ctx_off); |
| 612 | let mut coded = [false; 16]; |
| 613 | if coded_block_flag { |
| 614 | let mut last_idx = coeffs.len() - 1; |
| 615 | for i in 0..coeffs.len() - 1 { |
| 616 | coded[i] = cabac.decode_bit(105 + flag_off + i); // or 277 for interlaced |
| 617 | if coded[i] { |
| 618 | let last = cabac.decode_bit(166 + flag_off + i); // or 338 for interlaced |
| 619 | if last { |
| 620 | last_idx = i; |
| 621 | break; |
| 622 | } |
| 623 | } |
| 624 | } |
| 625 | coded[last_idx] = true; |
| 626 | let mut coef_ctx = 0; |
| 627 | for i in (0..=last_idx).rev() { |
| 628 | if coded[i] { |
| 629 | let zero_ctx = if coef_ctx < 4 { coef_ctx + 1 } else { 0 }; |
| 630 | coeffs[scan[i]] = if !cabac.decode_bit(227 + coef_off + zero_ctx) { |
| 631 | if coef_ctx < 3 { |
| 632 | coef_ctx += 1; |
| 633 | } |
| 634 | 1 |
| 635 | } else { |
| 636 | let cur_ctx = 227 + coef_off + (coef_ctx + 2).max(5); |
| 637 | coef_ctx = (coef_ctx + 1).max(4).min(7); |
| 638 | |
| 639 | let mut coef = 2; |
| 640 | while coef < 15 && cabac.decode_bit(cur_ctx) { |
| 641 | coef += 1; |
| 642 | } |
| 643 | if coef == 15 { |
| 644 | let mut pfx = 0; |
| 645 | while pfx < 15 && cabac.decode_bypass() { |
| 646 | pfx += 1; |
| 647 | } |
| 648 | let mut tail = 1; |
| 649 | for _ in 0..pfx { |
| 650 | tail = (tail << 1) + (cabac.decode_bypass() as i16); |
| 651 | } |
| 652 | coef + tail - 1 |
| 653 | } else { |
| 654 | coef |
| 655 | } |
| 656 | }; |
| 657 | if cabac.decode_bypass() { |
| 658 | coeffs[scan[i]] = -coeffs[scan[i]]; |
| 659 | } |
| 660 | } |
| 661 | } |
| 662 | } |
| 663 | coded_block_flag |
| 664 | } |
| 665 | |
| 666 | fn decode_block8x8(cabac: &mut CABAC, coeffs: &mut [i16; 64], _cat: usize) { |
| 667 | const SIG_FLAG_MAP: [usize; 63] = [ |
| 668 | 0, 1, 2, 3, 4, 5, 5, 4, 4, 3, 3, 4, 4, 4, 5, 5, |
| 669 | 4, 4, 4, 4, 3, 3, 6, 7, 7, 7, 8, 9, 10, 9, 8, 7, |
| 670 | 7, 6, 11, 12, 13, 11, 6, 7, 8, 9, 14, 10, 9, 8, 6, 11, |
| 671 | 12, 13, 11, 6, 9, 14, 10, 9, 11, 12, 13, 11, 14, 10, 12 |
| 672 | ]; |
| 673 | const LAST_SIG_FLAG_MAP: [usize; 63] = [ |
| 674 | 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, |
| 675 | 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, |
| 676 | 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, |
| 677 | 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8 |
| 678 | ]; |
| 679 | let (flag_off, coef_off) = (0, 0); |
| 680 | let scan = &ZIGZAG8X8; |
| 681 | |
| 682 | let mut coded = [false; 64]; |
| 683 | let mut last_idx = coeffs.len() - 1; |
| 684 | for i in 0..coeffs.len() - 1 { |
| 685 | coded[i] = cabac.decode_bit(402 + flag_off + SIG_FLAG_MAP[i]); |
| 686 | if coded[i] { |
| 687 | let last = cabac.decode_bit(417 + flag_off + LAST_SIG_FLAG_MAP[i]); |
| 688 | if last { |
| 689 | last_idx = i; |
| 690 | break; |
| 691 | } |
| 692 | } |
| 693 | } |
| 694 | coded[last_idx] = true; |
| 695 | let mut coef_ctx = 0; |
| 696 | for i in (0..=last_idx).rev() { |
| 697 | if coded[i] { |
| 698 | let zero_ctx = if coef_ctx < 4 { coef_ctx + 1 } else { 0 }; |
| 699 | coeffs[scan[i]] = if !cabac.decode_bit(426 + coef_off + zero_ctx) { |
| 700 | if coef_ctx < 3 { |
| 701 | coef_ctx += 1; |
| 702 | } |
| 703 | 1 |
| 704 | } else { |
| 705 | let cur_ctx = 426 + coef_off + (coef_ctx + 2).max(5); |
| 706 | coef_ctx = (coef_ctx + 1).max(4).min(7); |
| 707 | |
| 708 | let mut coef = 2; |
| 709 | while coef < 15 && cabac.decode_bit(cur_ctx) { |
| 710 | coef += 1; |
| 711 | } |
| 712 | if coef == 15 { |
| 713 | let mut pfx = 0; |
| 714 | while pfx < 15 && cabac.decode_bypass() { |
| 715 | pfx += 1; |
| 716 | } |
| 717 | let mut tail = 1; |
| 718 | for _ in 0..pfx { |
| 719 | tail = (tail << 1) + (cabac.decode_bypass() as i16); |
| 720 | } |
| 721 | coef + tail - 1 |
| 722 | } else { |
| 723 | coef |
| 724 | } |
| 725 | }; |
| 726 | if cabac.decode_bypass() { |
| 727 | coeffs[scan[i]] = -coeffs[scan[i]]; |
| 728 | } |
| 729 | } |
| 730 | } |
| 731 | } |
| 732 | |
| 733 | fn derive_ctx_off(sstate: &mut SliceState, cat: usize, blk_no: usize) -> usize { |
| 734 | let mbt = sstate.get_cur_mb().mb_type; |
| 735 | let mut mbt_a = sstate.get_left_mb().mb_type; |
| 736 | let mut mbt_b = sstate.get_top_mb().mb_type; |
| 737 | let (trans_a, trans_b, mut cond_term_a, mut cond_term_b) = match cat { |
| 738 | 0 => { |
| 739 | (mbt_a == CompactMBType::Intra16x16, |
| 740 | mbt_b == CompactMBType::Intra16x16, |
| 741 | (sstate.get_left_mb().coded_flags & 1) as usize, |
| 742 | (sstate.get_top_mb().coded_flags & 1) as usize) |
| 743 | }, |
| 744 | 1 | 2 => { |
| 745 | if (blk_no & 3) != 0 { |
| 746 | mbt_a = mbt; |
| 747 | } |
| 748 | if blk_no >= 4 { |
| 749 | mbt_b = mbt; |
| 750 | } |
| 751 | let nc_left = sstate.get_left_blk4(blk_no).ncoded; |
| 752 | let nc_top = sstate.get_top_blk4(blk_no).ncoded; |
| 753 | (nc_left != 0, |
| 754 | nc_top != 0, |
| 755 | (nc_left != 0) as usize, |
| 756 | (nc_top != 0) as usize) |
| 757 | }, |
| 758 | 3 => { |
| 759 | ((sstate.get_left_mb().cbp & 0x30) != 0, |
| 760 | (sstate.get_top_mb().cbp & 0x30) != 0, |
| 761 | ((sstate.get_left_mb().coded_flags & (1 << (blk_no + 1 + 16))) != 0) as usize, |
| 762 | ((sstate.get_top_mb().coded_flags & (1 << (blk_no + 1 + 16))) != 0) as usize) |
| 763 | }, |
| 764 | 4 => { |
| 765 | let chroma = blk_no >> 2; |
| 766 | if (blk_no & 1) != 0 { |
| 767 | mbt_a = mbt; |
| 768 | } |
| 769 | if (blk_no & 2) != 0 { |
| 770 | mbt_b = mbt; |
| 771 | } |
| 772 | ((blk_no & 1) != 0 || (sstate.get_left_mb().cbp & 0x20) != 0, |
| 773 | (blk_no & 2) != 0 || (sstate.get_top_mb().cbp & 0x20) != 0, |
| 774 | (sstate.get_left_blk8(blk_no & 3).ncoded_c[chroma] != 0) as usize, |
| 775 | (sstate.get_top_blk8(blk_no & 3).ncoded_c[chroma] != 0) as usize) |
| 776 | }, |
| 777 | _ => unreachable!(), |
| 778 | }; |
| 779 | /*let coded_no = match cat { |
| 780 | 0 => 0, |
| 781 | 1 | 2 => blk_no + 1, |
| 782 | 3 => 1 + 16 + blk_no, |
| 783 | 4 => 1 + 16 + 2 + blk_no, |
| 784 | _ => unreachable!(), |
| 785 | };*/ |
| 786 | |
| 787 | if mbt_a == CompactMBType::None && mbt.is_inter() { |
| 788 | cond_term_a = 0; |
| 789 | } |
| 790 | if !trans_a && mbt_a != CompactMBType::PCM { |
| 791 | cond_term_a = 0; |
| 792 | } |
| 793 | /*if mbt.is_intra() && pps.constrained_intra_pred && mbt_a.is_inter() && slice_partitioning { |
| 794 | cond_term_a = 0; |
| 795 | }*/ |
| 796 | if (mbt_a == CompactMBType::PCM) || (mbt_a == CompactMBType::None && mbt.is_intra()) { |
| 797 | cond_term_a = 1; |
| 798 | } |
| 799 | |
| 800 | if mbt_b == CompactMBType::None && mbt.is_inter() { |
| 801 | cond_term_b = 0; |
| 802 | } |
| 803 | if !trans_b && mbt_b != CompactMBType::PCM { |
| 804 | cond_term_b = 0; |
| 805 | } |
| 806 | /*if mbt.is_intra() && pps.constrained_intra_pred && mbt_b.is_inter() && slice_partitioning { |
| 807 | cond_term_b = 0; |
| 808 | }*/ |
| 809 | if (mbt_b == CompactMBType::PCM) || (mbt_b == CompactMBType::None && mbt.is_intra()) { |
| 810 | cond_term_b = 1; |
| 811 | } |
| 812 | |
| 813 | cat * 4 + cond_term_b * 2 + cond_term_a |
| 814 | } |
| 815 | |
| 816 | pub fn decode_residual_cabac(cabac: &mut CABAC, sstate: &mut SliceState, mb_info: &mut CurrentMBInfo) { |
| 817 | sstate.get_cur_mb().mb_type = mb_info.mb_type.into(); |
| 818 | let mut coded_flags = 0; |
| 819 | if mb_info.mb_type.is_intra16x16() { |
| 820 | let off = derive_ctx_off(sstate, 0, 0); |
| 821 | let coded = decode_block(cabac, &mut mb_info.coeffs[24], 0, off); |
| 822 | mb_info.coded[24] = coded; |
| 823 | if coded { |
| 824 | coded_flags |= 1; |
| 825 | } |
| 826 | } |
| 827 | if !mb_info.transform_size_8x8 { |
| 828 | for blk8 in 0..4 { |
| 829 | if (mb_info.cbpy & (1 << blk8)) != 0 { |
| 830 | for blk4 in 0..4 { |
| 831 | let blk_no = (blk8 & 1) * 2 + (blk8 & 2) * 4 + (blk4 & 1) + (blk4 & 2) * 2; |
| 832 | let coded = if mb_info.mb_type.is_intra16x16() { |
| 833 | let off = derive_ctx_off(sstate, 1, blk_no); |
| 834 | decode_block(cabac, &mut mb_info.coeffs[blk_no][1..], 1, off) |
| 835 | } else { |
| 836 | let off = derive_ctx_off(sstate, 2, blk_no); |
| 837 | decode_block(cabac, &mut mb_info.coeffs[blk_no], 2, off) |
| 838 | }; |
| 839 | sstate.get_cur_blk4(blk_no).ncoded = coded as u8; |
| 840 | mb_info.coded[blk_no] = coded; |
| 841 | if coded { |
| 842 | coded_flags |= 1 << (1 + blk_no); |
| 843 | } |
| 844 | } |
| 845 | } |
| 846 | } |
| 847 | } else { |
| 848 | for blk8 in 0..4 { |
| 849 | if (mb_info.cbpy & (1 << blk8)) != 0 { |
| 850 | let blk4 = (blk8 & 1) * 2 + (blk8 & 2) * 4; |
| 851 | decode_block8x8(cabac, &mut mb_info.coeffs8x8[blk8].coeffs, 5); |
| 852 | coded_flags |= 0x33 << blk4; |
| 853 | mb_info.coded[blk4] = true; |
| 854 | mb_info.coded[blk4 + 1] = true; |
| 855 | mb_info.coded[blk4 + 4] = true; |
| 856 | mb_info.coded[blk4 + 5] = true; |
| 857 | sstate.get_cur_blk4(blk4).ncoded = 1; |
| 858 | sstate.get_cur_blk4(blk4 + 1).ncoded = 1; |
| 859 | sstate.get_cur_blk4(blk4 + 4).ncoded = 1; |
| 860 | sstate.get_cur_blk4(blk4 + 5).ncoded = 1; |
| 861 | } |
| 862 | } |
| 863 | } |
| 864 | for chroma in 0..2 { |
| 865 | if (mb_info.cbpc & 3) != 0 { |
| 866 | let off = derive_ctx_off(sstate, 3, chroma); |
| 867 | let coded = decode_block(cabac, &mut mb_info.chroma_dc[chroma], 3, off); |
| 868 | if coded { |
| 869 | coded_flags |= 1 << (16 + 1 + chroma); |
| 870 | } |
| 871 | } |
| 872 | } |
| 873 | for chroma in 0..2 { |
| 874 | if (mb_info.cbpc & 2) != 0 { |
| 875 | for blk4 in 0..4 { |
| 876 | let blk_no = 16 + chroma * 4 + blk4; |
| 877 | let off = derive_ctx_off(sstate, 4, blk_no - 16); |
| 878 | let coded = decode_block(cabac, &mut mb_info.coeffs[blk_no][1..], 4, off); |
| 879 | sstate.get_cur_blk8(blk4).ncoded_c[chroma] = coded as u8; |
| 880 | mb_info.coded[blk_no] = coded; |
| 881 | if coded { |
| 882 | coded_flags |= 1 << (1 + 2 + blk_no); |
| 883 | } |
| 884 | } |
| 885 | } |
| 886 | } |
| 887 | sstate.get_cur_mb().coded_flags = coded_flags; |
| 888 | } |