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   1 /*
   2  * This file is part of FFmpeg.
   3  *
   4  * FFmpeg is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * FFmpeg is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with FFmpeg; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 static int FUNC(obu_header)(CodedBitstreamContext *ctx, RWContext *rw,
  20                             AV1RawOBUHeader *current)
  21 {
  22     CodedBitstreamAV1Context *priv = ctx->priv_data;
  23     int err;
  24
  25     HEADER("OBU header");
  26
  27     fc(1, obu_forbidden_bit, 0, 0);
  28
  29     fc(4, obu_type, 0, AV1_OBU_PADDING);
  30     flag(obu_extension_flag);
  31     flag(obu_has_size_field);
  32
  33     fc(1, obu_reserved_1bit, 0, 0);
  34
  35     if (current->obu_extension_flag) {
  36         fb(3, temporal_id);
  37         fb(2, spatial_id);
  38         fc(3, extension_header_reserved_3bits, 0, 0);
  39     } else {
  40         infer(temporal_id, 0);
  41         infer(spatial_id, 0);
  42     }
  43
  44     priv->temporal_id = current->temporal_id;
  45     priv->spatial_id  = current->spatial_id;
  46
  47     return 0;
  48 }
  49
  50 static int FUNC(trailing_bits)(CodedBitstreamContext *ctx, RWContext *rw, int nb_bits)
  51 {
  52     int err;
  53
  54     av_assert0(nb_bits > 0);
  55
  56     fixed(1, trailing_one_bit, 1);
  57     --nb_bits;
  58
  59     while (nb_bits > 0) {
  60         fixed(1, trailing_zero_bit, 0);
  61         --nb_bits;
  62     }
  63
  64     return 0;
  65 }
  66
  67 static int FUNC(byte_alignment)(CodedBitstreamContext *ctx, RWContext *rw)
  68 {
  69     int err;
  70
  71     while (byte_alignment(rw) != 0)
  72         fixed(1, zero_bit, 0);
  73
  74     return 0;
  75 }
  76
  77 static int FUNC(color_config)(CodedBitstreamContext *ctx, RWContext *rw,
  78                               AV1RawColorConfig *current, int seq_profile)
  79 {
  80     CodedBitstreamAV1Context *priv = ctx->priv_data;
  81     int err;
  82
  83     flag(high_bitdepth);
  84
  85     if (seq_profile == FF_PROFILE_AV1_PROFESSIONAL &&
  86         current->high_bitdepth) {
  87         flag(twelve_bit);
  88         priv->bit_depth = current->twelve_bit ? 12 : 10;
  89     } else {
  90         priv->bit_depth = current->high_bitdepth ? 10 : 8;
  91     }
  92
  93     if (seq_profile == FF_PROFILE_AV1_HIGH)
  94         infer(mono_chrome, 0);
  95     else
  96         flag(mono_chrome);
  97     priv->num_planes = current->mono_chrome ? 1 : 3;
  98
  99     flag(color_description_present_flag);
 100     if (current->color_description_present_flag) {
 101         fb(8, color_primaries);
 102         fb(8, transfer_characteristics);
 103         fb(8, matrix_coefficients);
 104     } else {
 105         infer(color_primaries,          AVCOL_PRI_UNSPECIFIED);
 106         infer(transfer_characteristics, AVCOL_TRC_UNSPECIFIED);
 107         infer(matrix_coefficients,      AVCOL_SPC_UNSPECIFIED);
 108     }
 109
 110     if (current->mono_chrome) {
 111         flag(color_range);
 112
 113         infer(subsampling_x, 1);
 114         infer(subsampling_y, 1);
 115         infer(chroma_sample_position, AV1_CSP_UNKNOWN);
 116         infer(separate_uv_delta_q, 0);
 117
 118     } else if (current->color_primaries          == AVCOL_PRI_BT709 &&
 119                current->transfer_characteristics == AVCOL_TRC_IEC61966_2_1 &&
 120                current->matrix_coefficients      == AVCOL_SPC_RGB) {
 121         infer(color_range,   1);
 122         infer(subsampling_x, 0);
 123         infer(subsampling_y, 0);
 124         flag(separate_uv_delta_q);
 125
 126     } else {
 127         flag(color_range);
 128
 129         if (seq_profile == FF_PROFILE_AV1_MAIN) {
 130             infer(subsampling_x, 1);
 131             infer(subsampling_y, 1);
 132         } else if (seq_profile == FF_PROFILE_AV1_HIGH) {
 133             infer(subsampling_x, 0);
 134             infer(subsampling_y, 0);
 135         } else {
 136             if (priv->bit_depth == 12) {
 137                 fb(1, subsampling_x);
 138                 if (current->subsampling_x)
 139                     fb(1, subsampling_y);
 140                 else
 141                     infer(subsampling_y, 0);
 142             } else {
 143                 infer(subsampling_x, 1);
 144                 infer(subsampling_y, 0);
 145             }
 146         }
 147         if (current->subsampling_x && current->subsampling_y) {
 148             fc(2, chroma_sample_position, AV1_CSP_UNKNOWN,
 149                                           AV1_CSP_COLOCATED);
 150         }
 151
 152         flag(separate_uv_delta_q);
 153     }
 154
 155     return 0;
 156 }
 157
 158 static int FUNC(timing_info)(CodedBitstreamContext *ctx, RWContext *rw,
 159                              AV1RawTimingInfo *current)
 160 {
 161     int err;
 162
 163     fc(32, num_units_in_display_tick, 1, MAX_UINT_BITS(32));
 164     fc(32, time_scale,                1, MAX_UINT_BITS(32));
 165
 166     flag(equal_picture_interval);
 167     if (current->equal_picture_interval)
 168         uvlc(num_ticks_per_picture_minus_1, 0, MAX_UINT_BITS(32) - 1);
 169
 170     return 0;
 171 }
 172
 173 static int FUNC(decoder_model_info)(CodedBitstreamContext *ctx, RWContext *rw,
 174                                     AV1RawDecoderModelInfo *current)
 175 {
 176     int err;
 177
 178     fb(5, buffer_delay_length_minus_1);
 179     fb(32, num_units_in_decoding_tick);
 180     fb(5,  buffer_removal_time_length_minus_1);
 181     fb(5,  frame_presentation_time_length_minus_1);
 182
 183     return 0;
 184 }
 185
 186 static int FUNC(sequence_header_obu)(CodedBitstreamContext *ctx, RWContext *rw,
 187                                      AV1RawSequenceHeader *current)
 188 {
 189     int i, err;
 190
 191     HEADER("Sequence Header");
 192
 193     fc(3, seq_profile, FF_PROFILE_AV1_MAIN,
 194                        FF_PROFILE_AV1_PROFESSIONAL);
 195     flag(still_picture);
 196     flag(reduced_still_picture_header);
 197
 198     if (current->reduced_still_picture_header) {
 199         infer(timing_info_present_flag,           0);
 200         infer(decoder_model_info_present_flag,    0);
 201         infer(initial_display_delay_present_flag, 0);
 202         infer(operating_points_cnt_minus_1,       0);
 203         infer(operating_point_idc[0],             0);
 204
 205         fb(5, seq_level_idx[0]);
 206
 207         infer(seq_tier[0], 0);
 208         infer(decoder_model_present_for_this_op[0],         0);
 209         infer(initial_display_delay_present_for_this_op[0], 0);
 210
 211     } else {
 212         flag(timing_info_present_flag);
 213         if (current->timing_info_present_flag) {
 214             CHECK(FUNC(timing_info)(ctx, rw, &current->timing_info));
 215
 216             flag(decoder_model_info_present_flag);
 217             if (current->decoder_model_info_present_flag) {
 218                 CHECK(FUNC(decoder_model_info)
 219                           (ctx, rw, &current->decoder_model_info));
 220             }
 221         } else {
 222             infer(decoder_model_info_present_flag, 0);
 223         }
 224
 225         flag(initial_display_delay_present_flag);
 226
 227         fb(5, operating_points_cnt_minus_1);
 228         for (i = 0; i <= current->operating_points_cnt_minus_1; i++) {
 229             fbs(12, operating_point_idc[i], 1, i);
 230             fbs(5,  seq_level_idx[i], 1, i);
 231
 232             if (current->seq_level_idx[i] > 7)
 233                 flags(seq_tier[i], 1, i);
 234             else
 235                 infer(seq_tier[i], 0);
 236
 237             if (current->decoder_model_info_present_flag) {
 238                 flags(decoder_model_present_for_this_op[i], 1, i);
 239                 if (current->decoder_model_present_for_this_op[i]) {
 240                     int n = current->decoder_model_info.buffer_delay_length_minus_1 + 1;
 241                     fbs(n, decoder_buffer_delay[i], 1, i);
 242                     fbs(n, encoder_buffer_delay[i], 1, i);
 243                     flags(low_delay_mode_flag[i], 1, i);
 244                 }
 245             } else {
 246                 infer(decoder_model_present_for_this_op[i], 0);
 247             }
 248
 249             if (current->initial_display_delay_present_flag) {
 250                 flags(initial_display_delay_present_for_this_op[i], 1, i);
 251                 if (current->initial_display_delay_present_for_this_op[i])
 252                     fbs(4, initial_display_delay_minus_1[i], 1, i);
 253             }
 254         }
 255     }
 256
 257     fb(4, frame_width_bits_minus_1);
 258     fb(4, frame_height_bits_minus_1);
 259
 260     fb(current->frame_width_bits_minus_1  + 1, max_frame_width_minus_1);
 261     fb(current->frame_height_bits_minus_1 + 1, max_frame_height_minus_1);
 262
 263     if (current->reduced_still_picture_header)
 264         infer(frame_id_numbers_present_flag, 0);
 265     else
 266         flag(frame_id_numbers_present_flag);
 267     if (current->frame_id_numbers_present_flag) {
 268         fb(4, delta_frame_id_length_minus_2);
 269         fb(3, additional_frame_id_length_minus_1);
 270     }
 271
 272     flag(use_128x128_superblock);
 273     flag(enable_filter_intra);
 274     flag(enable_intra_edge_filter);
 275
 276     if (current->reduced_still_picture_header) {
 277         infer(enable_interintra_compound, 0);
 278         infer(enable_masked_compound,     0);
 279         infer(enable_warped_motion,       0);
 280         infer(enable_dual_filter,         0);
 281         infer(enable_order_hint,          0);
 282         infer(enable_jnt_comp,            0);
 283         infer(enable_ref_frame_mvs,       0);
 284
 285         infer(seq_force_screen_content_tools,
 286               AV1_SELECT_SCREEN_CONTENT_TOOLS);
 287         infer(seq_force_integer_mv,
 288               AV1_SELECT_INTEGER_MV);
 289     } else {
 290         flag(enable_interintra_compound);
 291         flag(enable_masked_compound);
 292         flag(enable_warped_motion);
 293         flag(enable_dual_filter);
 294
 295         flag(enable_order_hint);
 296         if (current->enable_order_hint) {
 297             flag(enable_jnt_comp);
 298             flag(enable_ref_frame_mvs);
 299         } else {
 300             infer(enable_jnt_comp,      0);
 301             infer(enable_ref_frame_mvs, 0);
 302         }
 303
 304         flag(seq_choose_screen_content_tools);
 305         if (current->seq_choose_screen_content_tools)
 306             infer(seq_force_screen_content_tools,
 307                   AV1_SELECT_SCREEN_CONTENT_TOOLS);
 308         else
 309             fb(1, seq_force_screen_content_tools);
 310         if (current->seq_force_screen_content_tools > 0) {
 311             flag(seq_choose_integer_mv);
 312             if (current->seq_choose_integer_mv)
 313                 infer(seq_force_integer_mv,
 314                       AV1_SELECT_INTEGER_MV);
 315             else
 316                 fb(1, seq_force_integer_mv);
 317         } else {
 318             infer(seq_force_integer_mv, AV1_SELECT_INTEGER_MV);
 319         }
 320
 321         if (current->enable_order_hint)
 322             fb(3, order_hint_bits_minus_1);
 323     }
 324
 325     flag(enable_superres);
 326     flag(enable_cdef);
 327     flag(enable_restoration);
 328
 329     CHECK(FUNC(color_config)(ctx, rw, &current->color_config,
 330                              current->seq_profile));
 331
 332     flag(film_grain_params_present);
 333
 334     return 0;
 335 }
 336
 337 static int FUNC(temporal_delimiter_obu)(CodedBitstreamContext *ctx, RWContext *rw)
 338 {
 339     CodedBitstreamAV1Context *priv = ctx->priv_data;
 340
 341     HEADER("Temporal Delimiter");
 342
 343     priv->seen_frame_header = 0;
 344
 345     return 0;
 346 }
 347
 348 static int FUNC(set_frame_refs)(CodedBitstreamContext *ctx, RWContext *rw,
 349                                 AV1RawFrameHeader *current)
 350 {
 351     CodedBitstreamAV1Context *priv = ctx->priv_data;
 352     const AV1RawSequenceHeader *seq = priv->sequence_header;
 353     static const uint8_t ref_frame_list[AV1_NUM_REF_FRAMES - 2] = {
 354         AV1_REF_FRAME_LAST2, AV1_REF_FRAME_LAST3, AV1_REF_FRAME_BWDREF,
 355         AV1_REF_FRAME_ALTREF2, AV1_REF_FRAME_ALTREF
 356     };
 357     int8_t ref_frame_idx[AV1_REFS_PER_FRAME], used_frame[AV1_NUM_REF_FRAMES];
 358     int8_t shifted_order_hints[AV1_NUM_REF_FRAMES];
 359     int cur_frame_hint, latest_order_hint, earliest_order_hint, ref;
 360     int i, j;
 361
 362     for (i = 0; i < AV1_REFS_PER_FRAME; i++)
 363         ref_frame_idx[i] = -1;
 364     ref_frame_idx[AV1_REF_FRAME_LAST - AV1_REF_FRAME_LAST] = current->last_frame_idx;
 365     ref_frame_idx[AV1_REF_FRAME_GOLDEN - AV1_REF_FRAME_LAST] = current->golden_frame_idx;
 366
 367     for (i = 0; i < AV1_NUM_REF_FRAMES; i++)
 368         used_frame[i] = 0;
 369     used_frame[current->last_frame_idx] = 1;
 370     used_frame[current->golden_frame_idx] = 1;
 371
 372     cur_frame_hint = 1 << (seq->order_hint_bits_minus_1);
 373     for (i = 0; i < AV1_NUM_REF_FRAMES; i++)
 374         shifted_order_hints[i] = cur_frame_hint +
 375                                  cbs_av1_get_relative_dist(seq, priv->ref[i].order_hint,
 376                                                            priv->order_hint);
 377
 378     latest_order_hint = shifted_order_hints[current->last_frame_idx];
 379     earliest_order_hint = shifted_order_hints[current->golden_frame_idx];
 380
 381     ref = -1;
 382     for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
 383         int hint = shifted_order_hints[i];
 384         if (!used_frame[i] && hint >= cur_frame_hint &&
 385             (ref < 0 || hint >= latest_order_hint)) {
 386             ref = i;
 387             latest_order_hint = hint;
 388         }
 389     }
 390     if (ref >= 0) {
 391         ref_frame_idx[AV1_REF_FRAME_ALTREF - AV1_REF_FRAME_LAST] = ref;
 392         used_frame[ref] = 1;
 393     }
 394
 395     ref = -1;
 396     for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
 397         int hint = shifted_order_hints[i];
 398         if (!used_frame[i] && hint >= cur_frame_hint &&
 399             (ref < 0 || hint < earliest_order_hint)) {
 400             ref = i;
 401             earliest_order_hint = hint;
 402         }
 403     }
 404     if (ref >= 0) {
 405         ref_frame_idx[AV1_REF_FRAME_BWDREF - AV1_REF_FRAME_LAST] = ref;
 406         used_frame[ref] = 1;
 407     }
 408
 409     ref = -1;
 410     for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
 411         int hint = shifted_order_hints[i];
 412         if (!used_frame[i] && hint >= cur_frame_hint &&
 413             (ref < 0 || hint < earliest_order_hint)) {
 414             ref = i;
 415             earliest_order_hint = hint;
 416         }
 417     }
 418     if (ref >= 0) {
 419         ref_frame_idx[AV1_REF_FRAME_ALTREF2 - AV1_REF_FRAME_LAST] = ref;
 420         used_frame[ref] = 1;
 421     }
 422
 423     for (i = 0; i < AV1_REFS_PER_FRAME - 2; i++) {
 424         int ref_frame = ref_frame_list[i];
 425         if (ref_frame_idx[ref_frame - AV1_REF_FRAME_LAST] < 0 ) {
 426             ref = -1;
 427             for (j = 0; j < AV1_NUM_REF_FRAMES; j++) {
 428                 int hint = shifted_order_hints[j];
 429                 if (!used_frame[j] && hint < cur_frame_hint &&
 430                     (ref < 0 || hint >= latest_order_hint)) {
 431                     ref = j;
 432                     latest_order_hint = hint;
 433                 }
 434             }
 435             if (ref >= 0) {
 436                 ref_frame_idx[ref_frame - AV1_REF_FRAME_LAST] = ref;
 437                 used_frame[ref] = 1;
 438             }
 439         }
 440     }
 441
 442     ref = -1;
 443     for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
 444         int hint = shifted_order_hints[i];
 445         if (ref < 0 || hint < earliest_order_hint) {
 446             ref = i;
 447             earliest_order_hint = hint;
 448         }
 449     }
 450     for (i = 0; i < AV1_REFS_PER_FRAME; i++) {
 451         if (ref_frame_idx[i] < 0)
 452             ref_frame_idx[i] = ref;
 453         infer(ref_frame_idx[i], ref_frame_idx[i]);
 454     }
 455
 456     return 0;
 457 }
 458
 459 static int FUNC(superres_params)(CodedBitstreamContext *ctx, RWContext *rw,
 460                                  AV1RawFrameHeader *current)
 461 {
 462     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 463     const AV1RawSequenceHeader *seq = priv->sequence_header;
 464     int denom, err;
 465
 466     if (seq->enable_superres)
 467         flag(use_superres);
 468     else
 469         infer(use_superres, 0);
 470
 471     if (current->use_superres) {
 472         fb(3, coded_denom);
 473         denom = current->coded_denom + AV1_SUPERRES_DENOM_MIN;
 474     } else {
 475         denom = AV1_SUPERRES_NUM;
 476     }
 477
 478     priv->upscaled_width = priv->frame_width;
 479     priv->frame_width = (priv->upscaled_width * AV1_SUPERRES_NUM +
 480                          denom / 2) / denom;
 481
 482     return 0;
 483 }
 484
 485 static int FUNC(frame_size)(CodedBitstreamContext *ctx, RWContext *rw,
 486                             AV1RawFrameHeader *current)
 487 {
 488     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 489     const AV1RawSequenceHeader *seq = priv->sequence_header;
 490     int err;
 491
 492     if (current->frame_size_override_flag) {
 493         fb(seq->frame_width_bits_minus_1 + 1,  frame_width_minus_1);
 494         fb(seq->frame_height_bits_minus_1 + 1, frame_height_minus_1);
 495     } else {
 496         infer(frame_width_minus_1,  seq->max_frame_width_minus_1);
 497         infer(frame_height_minus_1, seq->max_frame_height_minus_1);
 498     }
 499
 500     priv->frame_width  = current->frame_width_minus_1  + 1;
 501     priv->frame_height = current->frame_height_minus_1 + 1;
 502
 503     CHECK(FUNC(superres_params)(ctx, rw, current));
 504
 505     return 0;
 506 }
 507
 508 static int FUNC(render_size)(CodedBitstreamContext *ctx, RWContext *rw,
 509                              AV1RawFrameHeader *current)
 510 {
 511     CodedBitstreamAV1Context *priv = ctx->priv_data;
 512     int err;
 513
 514     flag(render_and_frame_size_different);
 515
 516     if (current->render_and_frame_size_different) {
 517         fb(16, render_width_minus_1);
 518         fb(16, render_height_minus_1);
 519     } else {
 520         infer(render_width_minus_1,  current->frame_width_minus_1);
 521         infer(render_height_minus_1, current->frame_height_minus_1);
 522     }
 523
 524     priv->render_width  = current->render_width_minus_1  + 1;
 525     priv->render_height = current->render_height_minus_1 + 1;
 526
 527     return 0;
 528 }
 529
 530 static int FUNC(frame_size_with_refs)(CodedBitstreamContext *ctx, RWContext *rw,
 531                                       AV1RawFrameHeader *current)
 532 {
 533     CodedBitstreamAV1Context *priv = ctx->priv_data;
 534     int i, err;
 535
 536     for (i = 0; i < AV1_REFS_PER_FRAME; i++) {
 537         flags(found_ref[i], 1, i);
 538         if (current->found_ref[i]) {
 539             AV1ReferenceFrameState *ref =
 540                 &priv->ref[current->ref_frame_idx[i]];
 541
 542             if (!ref->valid) {
 543                 av_log(ctx->log_ctx, AV_LOG_ERROR,
 544                        "Missing reference frame needed for frame size "
 545                        "(ref = %d, ref_frame_idx = %d).\n",
 546                        i, current->ref_frame_idx[i]);
 547                 return AVERROR_INVALIDDATA;
 548             }
 549
 550             infer(frame_width_minus_1,   ref->upscaled_width - 1);
 551             infer(frame_height_minus_1,  ref->frame_height - 1);
 552             infer(render_width_minus_1,  ref->render_width - 1);
 553             infer(render_height_minus_1, ref->render_height - 1);
 554
 555             priv->upscaled_width = ref->upscaled_width;
 556             priv->frame_width    = ref->frame_width;
 557             priv->frame_height   = ref->frame_height;
 558             priv->render_width   = ref->render_width;
 559             priv->render_height  = ref->render_height;
 560             break;
 561         }
 562     }
 563
 564     if (i >= AV1_REFS_PER_FRAME) {
 565         CHECK(FUNC(frame_size)(ctx, rw, current));
 566         CHECK(FUNC(render_size)(ctx, rw, current));
 567     } else {
 568         CHECK(FUNC(superres_params)(ctx, rw, current));
 569     }
 570
 571     return 0;
 572 }
 573
 574 static int FUNC(interpolation_filter)(CodedBitstreamContext *ctx, RWContext *rw,
 575                                       AV1RawFrameHeader *current)
 576 {
 577     int err;
 578
 579     flag(is_filter_switchable);
 580     if (current->is_filter_switchable)
 581         infer(interpolation_filter,
 582               AV1_INTERPOLATION_FILTER_SWITCHABLE);
 583     else
 584         fb(2, interpolation_filter);
 585
 586     return 0;
 587 }
 588
 589 static int FUNC(tile_info)(CodedBitstreamContext *ctx, RWContext *rw,
 590                            AV1RawFrameHeader *current)
 591 {
 592     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 593     const AV1RawSequenceHeader *seq = priv->sequence_header;
 594     int mi_cols, mi_rows, sb_cols, sb_rows, sb_shift, sb_size;
 595     int max_tile_width_sb, max_tile_height_sb, max_tile_area_sb;
 596     int min_log2_tile_cols, max_log2_tile_cols, max_log2_tile_rows;
 597     int min_log2_tiles, min_log2_tile_rows;
 598     int i, err;
 599
 600     mi_cols = 2 * ((priv->frame_width  + 7) >> 3);
 601     mi_rows = 2 * ((priv->frame_height + 7) >> 3);
 602
 603     sb_cols = seq->use_128x128_superblock ? ((mi_cols + 31) >> 5)
 604                                           : ((mi_cols + 15) >> 4);
 605     sb_rows = seq->use_128x128_superblock ? ((mi_rows + 31) >> 5)
 606                                           : ((mi_rows + 15) >> 4);
 607
 608     sb_shift = seq->use_128x128_superblock ? 5 : 4;
 609     sb_size  = sb_shift + 2;
 610
 611     max_tile_width_sb = AV1_MAX_TILE_WIDTH >> sb_size;
 612     max_tile_area_sb  = AV1_MAX_TILE_AREA  >> (2 * sb_size);
 613
 614     min_log2_tile_cols = cbs_av1_tile_log2(max_tile_width_sb, sb_cols);
 615     max_log2_tile_cols = cbs_av1_tile_log2(1, FFMIN(sb_cols, AV1_MAX_TILE_COLS));
 616     max_log2_tile_rows = cbs_av1_tile_log2(1, FFMIN(sb_rows, AV1_MAX_TILE_ROWS));
 617     min_log2_tiles = FFMAX(min_log2_tile_cols,
 618                            cbs_av1_tile_log2(max_tile_area_sb, sb_rows * sb_cols));
 619
 620     flag(uniform_tile_spacing_flag);
 621
 622     if (current->uniform_tile_spacing_flag) {
 623         int tile_width_sb, tile_height_sb;
 624
 625         increment(tile_cols_log2, min_log2_tile_cols, max_log2_tile_cols);
 626
 627         tile_width_sb = (sb_cols + (1 << current->tile_cols_log2) - 1) >>
 628             current->tile_cols_log2;
 629         current->tile_cols = (sb_cols + tile_width_sb - 1) / tile_width_sb;
 630
 631         min_log2_tile_rows = FFMAX(min_log2_tiles - current->tile_cols_log2, 0);
 632
 633         increment(tile_rows_log2, min_log2_tile_rows, max_log2_tile_rows);
 634
 635         tile_height_sb = (sb_rows + (1 << current->tile_rows_log2) - 1) >>
 636             current->tile_rows_log2;
 637         current->tile_rows = (sb_rows + tile_height_sb - 1) / tile_height_sb;
 638
 639     } else {
 640         int widest_tile_sb, start_sb, size_sb, max_width, max_height;
 641
 642         widest_tile_sb = 0;
 643
 644         start_sb = 0;
 645         for (i = 0; start_sb < sb_cols && i < AV1_MAX_TILE_COLS; i++) {
 646             max_width = FFMIN(sb_cols - start_sb, max_tile_width_sb);
 647             ns(max_width, width_in_sbs_minus_1[i], 1, i);
 648             size_sb = current->width_in_sbs_minus_1[i] + 1;
 649             widest_tile_sb = FFMAX(size_sb, widest_tile_sb);
 650             start_sb += size_sb;
 651         }
 652         current->tile_cols_log2 = cbs_av1_tile_log2(1, i);
 653         current->tile_cols = i;
 654
 655         if (min_log2_tiles > 0)
 656             max_tile_area_sb = (sb_rows * sb_cols) >> (min_log2_tiles + 1);
 657         else
 658             max_tile_area_sb = sb_rows * sb_cols;
 659         max_tile_height_sb = FFMAX(max_tile_area_sb / widest_tile_sb, 1);
 660
 661         start_sb = 0;
 662         for (i = 0; start_sb < sb_rows && i < AV1_MAX_TILE_ROWS; i++) {
 663             max_height = FFMIN(sb_rows - start_sb, max_tile_height_sb);
 664             ns(max_height, height_in_sbs_minus_1[i], 1, i);
 665             size_sb = current->height_in_sbs_minus_1[i] + 1;
 666             start_sb += size_sb;
 667         }
 668         current->tile_rows_log2 = cbs_av1_tile_log2(1, i);
 669         current->tile_rows = i;
 670     }
 671
 672     if (current->tile_cols_log2 > 0 ||
 673         current->tile_rows_log2 > 0) {
 674         fb(current->tile_cols_log2 + current->tile_rows_log2,
 675            context_update_tile_id);
 676         fb(2, tile_size_bytes_minus1);
 677     } else {
 678         infer(context_update_tile_id, 0);
 679     }
 680
 681     priv->tile_cols = current->tile_cols;
 682     priv->tile_rows = current->tile_rows;
 683
 684     return 0;
 685 }
 686
 687 static int FUNC(quantization_params)(CodedBitstreamContext *ctx, RWContext *rw,
 688                                      AV1RawFrameHeader *current)
 689 {
 690     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 691     const AV1RawSequenceHeader *seq = priv->sequence_header;
 692     int err;
 693
 694     fb(8, base_q_idx);
 695
 696     delta_q(delta_q_y_dc);
 697
 698     if (priv->num_planes > 1) {
 699         if (seq->color_config.separate_uv_delta_q)
 700             flag(diff_uv_delta);
 701         else
 702             infer(diff_uv_delta, 0);
 703
 704         delta_q(delta_q_u_dc);
 705         delta_q(delta_q_u_ac);
 706
 707         if (current->diff_uv_delta) {
 708             delta_q(delta_q_v_dc);
 709             delta_q(delta_q_v_ac);
 710         } else {
 711             infer(delta_q_v_dc, current->delta_q_u_dc);
 712             infer(delta_q_v_ac, current->delta_q_u_ac);
 713         }
 714     } else {
 715         infer(delta_q_u_dc, 0);
 716         infer(delta_q_u_ac, 0);
 717         infer(delta_q_v_dc, 0);
 718         infer(delta_q_v_ac, 0);
 719     }
 720
 721     flag(using_qmatrix);
 722     if (current->using_qmatrix) {
 723         fb(4, qm_y);
 724         fb(4, qm_u);
 725         if (seq->color_config.separate_uv_delta_q)
 726             fb(4, qm_v);
 727         else
 728             infer(qm_v, current->qm_u);
 729     }
 730
 731     return 0;
 732 }
 733
 734 static int FUNC(segmentation_params)(CodedBitstreamContext *ctx, RWContext *rw,
 735                                      AV1RawFrameHeader *current)
 736 {
 737     static const uint8_t bits[AV1_SEG_LVL_MAX] = { 8, 6, 6, 6, 6, 3, 0, 0 };
 738     static const uint8_t sign[AV1_SEG_LVL_MAX] = { 1, 1, 1, 1, 1, 0, 0, 0 };
 739     int i, j, err;
 740
 741     flag(segmentation_enabled);
 742
 743     if (current->segmentation_enabled) {
 744         if (current->primary_ref_frame == AV1_PRIMARY_REF_NONE) {
 745             infer(segmentation_update_map,      1);
 746             infer(segmentation_temporal_update, 0);
 747             infer(segmentation_update_data,     1);
 748         } else {
 749             flag(segmentation_update_map);
 750             if (current->segmentation_update_map)
 751                 flag(segmentation_temporal_update);
 752             else
 753                 infer(segmentation_temporal_update, 0);
 754             flag(segmentation_update_data);
 755         }
 756
 757         if (current->segmentation_update_data) {
 758             for (i = 0; i < AV1_MAX_SEGMENTS; i++) {
 759                 for (j = 0; j < AV1_SEG_LVL_MAX; j++) {
 760                     flags(feature_enabled[i][j], 2, i, j);
 761
 762                     if (current->feature_enabled[i][j] && bits[j] > 0) {
 763                         if (sign[j])
 764                             sus(1 + bits[j], feature_value[i][j], 2, i, j);
 765                         else
 766                             fbs(bits[j], feature_value[i][j], 2, i, j);
 767                     } else {
 768                         infer(feature_value[i][j], 0);
 769                     }
 770                 }
 771             }
 772         }
 773     } else {
 774         for (i = 0; i < AV1_MAX_SEGMENTS; i++) {
 775             for (j = 0; j < AV1_SEG_LVL_MAX; j++) {
 776                 infer(feature_enabled[i][j], 0);
 777                 infer(feature_value[i][j],   0);
 778             }
 779         }
 780     }
 781
 782     return 0;
 783 }
 784
 785 static int FUNC(delta_q_params)(CodedBitstreamContext *ctx, RWContext *rw,
 786                                 AV1RawFrameHeader *current)
 787 {
 788     int err;
 789
 790     if (current->base_q_idx > 0)
 791         flag(delta_q_present);
 792     else
 793         infer(delta_q_present, 0);
 794
 795     if (current->delta_q_present)
 796         fb(2, delta_q_res);
 797
 798     return 0;
 799 }
 800
 801 static int FUNC(delta_lf_params)(CodedBitstreamContext *ctx, RWContext *rw,
 802                                  AV1RawFrameHeader *current)
 803 {
 804     int err;
 805
 806     if (current->delta_q_present) {
 807         if (!current->allow_intrabc)
 808             flag(delta_lf_present);
 809         else
 810             infer(delta_lf_present, 0);
 811         if (current->delta_lf_present) {
 812             fb(2, delta_lf_res);
 813             flag(delta_lf_multi);
 814         } else {
 815             infer(delta_lf_res,   0);
 816             infer(delta_lf_multi, 0);
 817         }
 818     } else {
 819         infer(delta_lf_present, 0);
 820         infer(delta_lf_res,     0);
 821         infer(delta_lf_multi,   0);
 822     }
 823
 824     return 0;
 825 }
 826
 827 static int FUNC(loop_filter_params)(CodedBitstreamContext *ctx, RWContext *rw,
 828                                     AV1RawFrameHeader *current)
 829 {
 830     CodedBitstreamAV1Context *priv = ctx->priv_data;
 831     int i, err;
 832
 833     if (priv->coded_lossless || current->allow_intrabc) {
 834         infer(loop_filter_level[0], 0);
 835         infer(loop_filter_level[1], 0);
 836         infer(loop_filter_ref_deltas[AV1_REF_FRAME_INTRA],    1);
 837         infer(loop_filter_ref_deltas[AV1_REF_FRAME_LAST],     0);
 838         infer(loop_filter_ref_deltas[AV1_REF_FRAME_LAST2],    0);
 839         infer(loop_filter_ref_deltas[AV1_REF_FRAME_LAST3],    0);
 840         infer(loop_filter_ref_deltas[AV1_REF_FRAME_BWDREF],   0);
 841         infer(loop_filter_ref_deltas[AV1_REF_FRAME_GOLDEN],  -1);
 842         infer(loop_filter_ref_deltas[AV1_REF_FRAME_ALTREF],  -1);
 843         infer(loop_filter_ref_deltas[AV1_REF_FRAME_ALTREF2], -1);
 844         for (i = 0; i < 2; i++)
 845             infer(loop_filter_mode_deltas[i], 0);
 846         return 0;
 847     }
 848
 849     fb(6, loop_filter_level[0]);
 850     fb(6, loop_filter_level[1]);
 851
 852     if (priv->num_planes > 1) {
 853         if (current->loop_filter_level[0] ||
 854             current->loop_filter_level[1]) {
 855             fb(6, loop_filter_level[2]);
 856             fb(6, loop_filter_level[3]);
 857         }
 858     }
 859
 860     fb(3, loop_filter_sharpness);
 861
 862     flag(loop_filter_delta_enabled);
 863     if (current->loop_filter_delta_enabled) {
 864         flag(loop_filter_delta_update);
 865         if (current->loop_filter_delta_update) {
 866             for (i = 0; i < AV1_TOTAL_REFS_PER_FRAME; i++) {
 867                 flags(update_ref_delta[i], 1, i);
 868                 if (current->update_ref_delta[i])
 869                     sus(1 + 6, loop_filter_ref_deltas[i], 1, i);
 870             }
 871             for (i = 0; i < 2; i++) {
 872                 flags(update_mode_delta[i], 1, i);
 873                 if (current->update_mode_delta[i])
 874                     sus(1 + 6, loop_filter_mode_deltas[i], 1, i);
 875             }
 876         }
 877     }
 878
 879     return 0;
 880 }
 881
 882 static int FUNC(cdef_params)(CodedBitstreamContext *ctx, RWContext *rw,
 883                              AV1RawFrameHeader *current)
 884 {
 885     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 886     const AV1RawSequenceHeader *seq = priv->sequence_header;
 887     int i, err;
 888
 889     if (priv->coded_lossless || current->allow_intrabc ||
 890         !seq->enable_cdef) {
 891         infer(cdef_damping_minus_3, 0);
 892         infer(cdef_bits, 0);
 893         infer(cdef_y_pri_strength[0],  0);
 894         infer(cdef_y_sec_strength[0],  0);
 895         infer(cdef_uv_pri_strength[0], 0);
 896         infer(cdef_uv_sec_strength[0], 0);
 897
 898         return 0;
 899     }
 900
 901     fb(2, cdef_damping_minus_3);
 902     fb(2, cdef_bits);
 903
 904     for (i = 0; i < (1 << current->cdef_bits); i++) {
 905         fbs(4, cdef_y_pri_strength[i], 1, i);
 906         fbs(2, cdef_y_sec_strength[i], 1, i);
 907
 908         if (priv->num_planes > 1) {
 909             fbs(4, cdef_uv_pri_strength[i], 1, i);
 910             fbs(2, cdef_uv_sec_strength[i], 1, i);
 911         }
 912     }
 913
 914     return 0;
 915 }
 916
 917 static int FUNC(lr_params)(CodedBitstreamContext *ctx, RWContext *rw,
 918                            AV1RawFrameHeader *current)
 919 {
 920     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 921     const AV1RawSequenceHeader *seq = priv->sequence_header;
 922     int uses_lr,  uses_chroma_lr;
 923     int i, err;
 924
 925     if (priv->all_lossless || current->allow_intrabc ||
 926         !seq->enable_restoration) {
 927         return 0;
 928     }
 929
 930     uses_lr = uses_chroma_lr = 0;
 931     for (i = 0; i < priv->num_planes; i++) {
 932         fbs(2, lr_type[i], 1, i);
 933
 934         if (current->lr_type[i] != 0) {
 935             uses_lr = 1;
 936             if (i > 0)
 937                 uses_chroma_lr = 1;
 938         }
 939     }
 940
 941     if (uses_lr) {
 942         if (seq->use_128x128_superblock)
 943             increment(lr_unit_shift, 1, 2);
 944         else
 945             increment(lr_unit_shift, 0, 2);
 946
 947         if(seq->color_config.subsampling_x &&
 948            seq->color_config.subsampling_y && uses_chroma_lr) {
 949             fb(1, lr_uv_shift);
 950         } else {
 951             infer(lr_uv_shift, 0);
 952         }
 953     }
 954
 955     return 0;
 956 }
 957
 958 static int FUNC(read_tx_mode)(CodedBitstreamContext *ctx, RWContext *rw,
 959                               AV1RawFrameHeader *current)
 960 {
 961     CodedBitstreamAV1Context *priv = ctx->priv_data;
 962     int err;
 963
 964     if (priv->coded_lossless)
 965         infer(tx_mode, 0);
 966     else
 967         increment(tx_mode, 1, 2);
 968
 969     return 0;
 970 }
 971
 972 static int FUNC(frame_reference_mode)(CodedBitstreamContext *ctx, RWContext *rw,
 973                                       AV1RawFrameHeader *current)
 974 {
 975     int err;
 976
 977     if (current->frame_type == AV1_FRAME_INTRA_ONLY ||
 978         current->frame_type == AV1_FRAME_KEY)
 979         infer(reference_select, 0);
 980     else
 981         flag(reference_select);
 982
 983     return 0;
 984 }
 985
 986 static int FUNC(skip_mode_params)(CodedBitstreamContext *ctx, RWContext *rw,
 987                                   AV1RawFrameHeader *current)
 988 {
 989     CodedBitstreamAV1Context  *priv = ctx->priv_data;
 990     const AV1RawSequenceHeader *seq = priv->sequence_header;
 991     int skip_mode_allowed;
 992     int err;
 993
 994     if (current->frame_type == AV1_FRAME_KEY ||
 995         current->frame_type == AV1_FRAME_INTRA_ONLY ||
 996         !current->reference_select || !seq->enable_order_hint) {
 997         skip_mode_allowed = 0;
 998     } else {
 999         int forward_idx,  backward_idx;
1000         int forward_hint, backward_hint;
1001         int ref_hint, dist, i;
1002
1003         forward_idx  = -1;
1004         backward_idx = -1;
1005         for (i = 0; i < AV1_REFS_PER_FRAME; i++) {
1006             ref_hint = priv->ref[current->ref_frame_idx[i]].order_hint;
1007             dist = cbs_av1_get_relative_dist(seq, ref_hint,
1008                                              priv->order_hint);
1009             if (dist < 0) {
1010                 if (forward_idx < 0 ||
1011                     cbs_av1_get_relative_dist(seq, ref_hint,
1012                                               forward_hint) > 0) {
1013                     forward_idx  = i;
1014                     forward_hint = ref_hint;
1015                 }
1016             } else if (dist > 0) {
1017                 if (backward_idx < 0 ||
1018                     cbs_av1_get_relative_dist(seq, ref_hint,
1019                                               backward_hint) < 0) {
1020                     backward_idx  = i;
1021                     backward_hint = ref_hint;
1022                 }
1023             }
1024         }
1025
1026         if (forward_idx < 0) {
1027             skip_mode_allowed = 0;
1028         } else if (backward_idx >= 0) {
1029             skip_mode_allowed = 1;
1030             // Frames for skip mode are forward_idx and backward_idx.
1031         } else {
1032             int second_forward_idx;
1033             int second_forward_hint;
1034
1035             second_forward_idx = -1;
1036             for (i = 0; i < AV1_REFS_PER_FRAME; i++) {
1037                 ref_hint = priv->ref[current->ref_frame_idx[i]].order_hint;
1038                 if (cbs_av1_get_relative_dist(seq, ref_hint,
1039                                               forward_hint) < 0) {
1040                     if (second_forward_idx < 0 ||
1041                         cbs_av1_get_relative_dist(seq, ref_hint,
1042                                                   second_forward_hint) > 0) {
1043                         second_forward_idx  = i;
1044                         second_forward_hint = ref_hint;
1045                     }
1046                 }
1047             }
1048
1049             if (second_forward_idx < 0) {
1050                 skip_mode_allowed = 0;
1051             } else {
1052                 skip_mode_allowed = 1;
1053                 // Frames for skip mode are forward_idx and second_forward_idx.
1054             }
1055         }
1056     }
1057
1058     if (skip_mode_allowed)
1059         flag(skip_mode_present);
1060     else
1061         infer(skip_mode_present, 0);
1062
1063     return 0;
1064 }
1065
1066 static int FUNC(global_motion_param)(CodedBitstreamContext *ctx, RWContext *rw,
1067                                      AV1RawFrameHeader *current,
1068                                      int type, int ref, int idx)
1069 {
1070     uint32_t abs_bits, prec_bits, num_syms;
1071     int err;
1072
1073     if (idx < 2) {
1074         if (type == AV1_WARP_MODEL_TRANSLATION) {
1075             abs_bits  = AV1_GM_ABS_TRANS_ONLY_BITS  - !current->allow_high_precision_mv;
1076             prec_bits = AV1_GM_TRANS_ONLY_PREC_BITS - !current->allow_high_precision_mv;
1077         } else {
1078             abs_bits  = AV1_GM_ABS_TRANS_BITS;
1079             prec_bits = AV1_GM_TRANS_PREC_BITS;
1080         }
1081     } else {
1082         abs_bits  = AV1_GM_ABS_ALPHA_BITS;
1083         prec_bits = AV1_GM_ALPHA_PREC_BITS;
1084     }
1085
1086     num_syms = 2 * (1 << abs_bits) + 1;
1087     subexp(gm_params[ref][idx], num_syms, 2, ref, idx);
1088
1089     // Actual gm_params value is not reconstructed here.
1090     (void)prec_bits;
1091
1092     return 0;
1093 }
1094
1095 static int FUNC(global_motion_params)(CodedBitstreamContext *ctx, RWContext *rw,
1096                                       AV1RawFrameHeader *current)
1097 {
1098     int ref, type;
1099     int err;
1100
1101     if (current->frame_type == AV1_FRAME_KEY ||
1102         current->frame_type == AV1_FRAME_INTRA_ONLY)
1103         return 0;
1104
1105     for (ref = AV1_REF_FRAME_LAST; ref <= AV1_REF_FRAME_ALTREF; ref++) {
1106         flags(is_global[ref], 1, ref);
1107         if (current->is_global[ref]) {
1108             flags(is_rot_zoom[ref], 1, ref);
1109             if (current->is_rot_zoom[ref]) {
1110                 type = AV1_WARP_MODEL_ROTZOOM;
1111             } else {
1112                 flags(is_translation[ref], 1, ref);
1113                 type = current->is_translation[ref] ? AV1_WARP_MODEL_TRANSLATION
1114                                                     : AV1_WARP_MODEL_AFFINE;
1115             }
1116         } else {
1117             type = AV1_WARP_MODEL_IDENTITY;
1118         }
1119
1120         if (type >= AV1_WARP_MODEL_ROTZOOM) {
1121             CHECK(FUNC(global_motion_param)(ctx, rw, current, type, ref, 2));
1122             CHECK(FUNC(global_motion_param)(ctx, rw, current, type, ref, 3));
1123             if (type == AV1_WARP_MODEL_AFFINE) {
1124                 CHECK(FUNC(global_motion_param)(ctx, rw, current, type, ref, 4));
1125                 CHECK(FUNC(global_motion_param)(ctx, rw, current, type, ref, 5));
1126             } else {
1127                 // gm_params[ref][4] = -gm_params[ref][3]
1128                 // gm_params[ref][5] =  gm_params[ref][2]
1129             }
1130         }
1131         if (type >= AV1_WARP_MODEL_TRANSLATION) {
1132             CHECK(FUNC(global_motion_param)(ctx, rw, current, type, ref, 0));
1133             CHECK(FUNC(global_motion_param)(ctx, rw, current, type, ref, 1));
1134         }
1135     }
1136
1137     return 0;
1138 }
1139
1140 static int FUNC(film_grain_params)(CodedBitstreamContext *ctx, RWContext *rw,
1141                                    AV1RawFrameHeader *current)
1142 {
1143     CodedBitstreamAV1Context  *priv = ctx->priv_data;
1144     const AV1RawSequenceHeader *seq = priv->sequence_header;
1145     int num_pos_luma, num_pos_chroma;
1146     int i, err;
1147
1148     if (!seq->film_grain_params_present ||
1149         (!current->show_frame && !current->showable_frame))
1150         return 0;
1151
1152     flag(apply_grain);
1153
1154     if (!current->apply_grain)
1155         return 0;
1156
1157     fb(16, grain_seed);
1158
1159     if (current->frame_type == AV1_FRAME_INTER)
1160         flag(update_grain);
1161     else
1162         infer(update_grain, 1);
1163
1164     if (!current->update_grain) {
1165         fb(3, film_grain_params_ref_idx);
1166         return 0;
1167     }
1168
1169     fc(4, num_y_points, 0, 14);
1170     for (i = 0; i < current->num_y_points; i++) {
1171         fcs(8, point_y_value[i],
1172             i ? current->point_y_value[i - 1] + 1 : 0,
1173             MAX_UINT_BITS(8) - (current->num_y_points - i - 1),
1174             1, i);
1175         fbs(8, point_y_scaling[i], 1, i);
1176     }
1177
1178     if (seq->color_config.mono_chrome)
1179         infer(chroma_scaling_from_luma, 0);
1180     else
1181         flag(chroma_scaling_from_luma);
1182
1183     if (seq->color_config.mono_chrome ||
1184         current->chroma_scaling_from_luma ||
1185         (seq->color_config.subsampling_x == 1 &&
1186          seq->color_config.subsampling_y == 1 &&
1187          current->num_y_points == 0)) {
1188         infer(num_cb_points, 0);
1189         infer(num_cr_points, 0);
1190     } else {
1191         fc(4, num_cb_points, 0, 10);
1192         for (i = 0; i < current->num_cb_points; i++) {
1193             fcs(8, point_cb_value[i],
1194                 i ? current->point_cb_value[i - 1] + 1 : 0,
1195                 MAX_UINT_BITS(8) - (current->num_cb_points - i - 1),
1196                 1, i);
1197             fbs(8, point_cb_scaling[i], 1, i);
1198         }
1199         fc(4, num_cr_points, 0, 10);
1200         for (i = 0; i < current->num_cr_points; i++) {
1201             fcs(8, point_cr_value[i],
1202                 i ? current->point_cr_value[i - 1] + 1 : 0,
1203                 MAX_UINT_BITS(8) - (current->num_cr_points - i - 1),
1204                 1, i);
1205             fbs(8, point_cr_scaling[i], 1, i);
1206         }
1207     }
1208
1209     fb(2, grain_scaling_minus_8);
1210     fb(2, ar_coeff_lag);
1211     num_pos_luma = 2 * current->ar_coeff_lag * (current->ar_coeff_lag + 1);
1212     if (current->num_y_points) {
1213         num_pos_chroma = num_pos_luma + 1;
1214         for (i = 0; i < num_pos_luma; i++)
1215             fbs(8, ar_coeffs_y_plus_128[i], 1, i);
1216     } else {
1217         num_pos_chroma = num_pos_luma;
1218     }
1219     if (current->chroma_scaling_from_luma || current->num_cb_points) {
1220         for (i = 0; i < num_pos_chroma; i++)
1221             fbs(8, ar_coeffs_cb_plus_128[i], 1, i);
1222     }
1223     if (current->chroma_scaling_from_luma || current->num_cr_points) {
1224         for (i = 0; i < num_pos_chroma; i++)
1225             fbs(8, ar_coeffs_cr_plus_128[i], 1, i);
1226     }
1227     fb(2, ar_coeff_shift_minus_6);
1228     fb(2, grain_scale_shift);
1229     if (current->num_cb_points) {
1230         fb(8, cb_mult);
1231         fb(8, cb_luma_mult);
1232         fb(9, cb_offset);
1233     }
1234     if (current->num_cr_points) {
1235         fb(8, cr_mult);
1236         fb(8, cr_luma_mult);
1237         fb(9, cr_offset);
1238     }
1239
1240     flag(overlap_flag);
1241     flag(clip_to_restricted_range);
1242
1243     return 0;
1244 }
1245
1246 static int FUNC(uncompressed_header)(CodedBitstreamContext *ctx, RWContext *rw,
1247                                      AV1RawFrameHeader *current)
1248 {
1249     CodedBitstreamAV1Context *priv = ctx->priv_data;
1250     const AV1RawSequenceHeader *seq;
1251     int id_len, diff_len, all_frames, frame_is_intra, order_hint_bits;
1252     int i, err;
1253
1254     if (!priv->sequence_header) {
1255         av_log(ctx->log_ctx, AV_LOG_ERROR, "No sequence header available: "
1256                "unable to decode frame header.\n");
1257         return AVERROR_INVALIDDATA;
1258     }
1259     seq = priv->sequence_header;
1260
1261     id_len = seq->additional_frame_id_length_minus_1 +
1262              seq->delta_frame_id_length_minus_2 + 3;
1263     all_frames = (1 << AV1_NUM_REF_FRAMES) - 1;
1264
1265     if (seq->reduced_still_picture_header) {
1266         infer(show_existing_frame, 0);
1267         infer(frame_type,     AV1_FRAME_KEY);
1268         infer(show_frame,     1);
1269         infer(showable_frame, 0);
1270         frame_is_intra = 1;
1271
1272     } else {
1273         flag(show_existing_frame);
1274
1275         if (current->show_existing_frame) {
1276             AV1ReferenceFrameState *frame;
1277
1278             fb(3, frame_to_show_map_idx);
1279             frame = &priv->ref[current->frame_to_show_map_idx];
1280
1281             if (!frame->valid) {
1282                 av_log(ctx->log_ctx, AV_LOG_ERROR, "Missing reference frame needed for "
1283                        "show_existing_frame (frame_to_show_map_idx = %d).\n",
1284                        current->frame_to_show_map_idx);
1285                 return AVERROR_INVALIDDATA;
1286             }
1287
1288             if (seq->decoder_model_info_present_flag &&
1289                 !seq->timing_info.equal_picture_interval) {
1290                 fb(seq->decoder_model_info.frame_presentation_time_length_minus_1 + 1,
1291                    frame_presentation_time);
1292             }
1293
1294             if (seq->frame_id_numbers_present_flag)
1295                 fb(id_len, display_frame_id);
1296
1297             infer(frame_type, frame->frame_type);
1298             if (current->frame_type == AV1_FRAME_KEY) {
1299                 infer(refresh_frame_flags, all_frames);
1300
1301                 // Section 7.21
1302                 infer(current_frame_id, frame->frame_id);
1303                 priv->upscaled_width  = frame->upscaled_width;
1304                 priv->frame_width     = frame->frame_width;
1305                 priv->frame_height    = frame->frame_height;
1306                 priv->render_width    = frame->render_width;
1307                 priv->render_height   = frame->render_height;
1308                 priv->bit_depth       = frame->bit_depth;
1309                 priv->order_hint      = frame->order_hint;
1310             } else
1311                 infer(refresh_frame_flags, 0);
1312
1313             infer(frame_width_minus_1,   frame->upscaled_width - 1);
1314             infer(frame_height_minus_1,  frame->frame_height - 1);
1315             infer(render_width_minus_1,  frame->render_width - 1);
1316             infer(render_height_minus_1, frame->render_height - 1);
1317
1318             // Section 7.20
1319             goto update_refs;
1320         }
1321
1322         fb(2, frame_type);
1323         frame_is_intra = (current->frame_type == AV1_FRAME_INTRA_ONLY ||
1324                           current->frame_type == AV1_FRAME_KEY);
1325
1326         flag(show_frame);
1327         if (current->show_frame &&
1328             seq->decoder_model_info_present_flag &&
1329             !seq->timing_info.equal_picture_interval) {
1330             fb(seq->decoder_model_info.frame_presentation_time_length_minus_1 + 1,
1331                frame_presentation_time);
1332         }
1333         if (current->show_frame)
1334             infer(showable_frame, current->frame_type != AV1_FRAME_KEY);
1335         else
1336             flag(showable_frame);
1337
1338         if (current->frame_type == AV1_FRAME_SWITCH ||
1339             (current->frame_type == AV1_FRAME_KEY && current->show_frame))
1340             infer(error_resilient_mode, 1);
1341         else
1342             flag(error_resilient_mode);
1343     }
1344
1345     if (current->frame_type == AV1_FRAME_KEY && current->show_frame) {
1346         for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
1347             priv->ref[i].valid = 0;
1348             priv->ref[i].order_hint = 0;
1349         }
1350     }
1351
1352     flag(disable_cdf_update);
1353
1354     if (seq->seq_force_screen_content_tools ==
1355         AV1_SELECT_SCREEN_CONTENT_TOOLS) {
1356         flag(allow_screen_content_tools);
1357     } else {
1358         infer(allow_screen_content_tools,
1359               seq->seq_force_screen_content_tools);
1360     }
1361     if (current->allow_screen_content_tools) {
1362         if (seq->seq_force_integer_mv == AV1_SELECT_INTEGER_MV)
1363             flag(force_integer_mv);
1364         else
1365             infer(force_integer_mv, seq->seq_force_integer_mv);
1366     } else {
1367         infer(force_integer_mv, 0);
1368     }
1369
1370     if (seq->frame_id_numbers_present_flag) {
1371         fb(id_len, current_frame_id);
1372
1373         diff_len = seq->delta_frame_id_length_minus_2 + 2;
1374         for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
1375             if (current->current_frame_id > (1 << diff_len)) {
1376                 if (priv->ref[i].frame_id > current->current_frame_id ||
1377                     priv->ref[i].frame_id < (current->current_frame_id -
1378                                              (1 << diff_len)))
1379                     priv->ref[i].valid = 0;
1380             } else {
1381                 if (priv->ref[i].frame_id > current->current_frame_id &&
1382                     priv->ref[i].frame_id < ((1 << id_len) +
1383                                              current->current_frame_id -
1384                                              (1 << diff_len)))
1385                     priv->ref[i].valid = 0;
1386             }
1387         }
1388     } else {
1389         infer(current_frame_id, 0);
1390     }
1391
1392     if (current->frame_type == AV1_FRAME_SWITCH)
1393         infer(frame_size_override_flag, 1);
1394     else if(seq->reduced_still_picture_header)
1395         infer(frame_size_override_flag, 0);
1396     else
1397         flag(frame_size_override_flag);
1398
1399     order_hint_bits =
1400         seq->enable_order_hint ? seq->order_hint_bits_minus_1 + 1 : 0;
1401     if (order_hint_bits > 0)
1402         fb(order_hint_bits, order_hint);
1403     else
1404         infer(order_hint, 0);
1405     priv->order_hint = current->order_hint;
1406
1407     if (frame_is_intra || current->error_resilient_mode)
1408         infer(primary_ref_frame, AV1_PRIMARY_REF_NONE);
1409     else
1410         fb(3, primary_ref_frame);
1411
1412     if (seq->decoder_model_info_present_flag) {
1413         flag(buffer_removal_time_present_flag);
1414         if (current->buffer_removal_time_present_flag) {
1415             for (i = 0; i <= seq->operating_points_cnt_minus_1; i++) {
1416                 if (seq->decoder_model_present_for_this_op[i]) {
1417                     int op_pt_idc = seq->operating_point_idc[i];
1418                     int in_temporal_layer = (op_pt_idc >>  priv->temporal_id    ) & 1;
1419                     int in_spatial_layer  = (op_pt_idc >> (priv->spatial_id + 8)) & 1;
1420                     if (seq->operating_point_idc[i] == 0 ||
1421                         (in_temporal_layer && in_spatial_layer)) {
1422                         fbs(seq->decoder_model_info.buffer_removal_time_length_minus_1 + 1,
1423                             buffer_removal_time[i], 1, i);
1424                     }
1425                 }
1426             }
1427         }
1428     }
1429
1430     if (current->frame_type == AV1_FRAME_SWITCH ||
1431         (current->frame_type == AV1_FRAME_KEY && current->show_frame))
1432         infer(refresh_frame_flags, all_frames);
1433     else
1434         fb(8, refresh_frame_flags);
1435
1436     if (!frame_is_intra || current->refresh_frame_flags != all_frames) {
1437         if (current->error_resilient_mode && seq->enable_order_hint) {
1438             for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
1439                 fbs(order_hint_bits, ref_order_hint[i], 1, i);
1440                 if (current->ref_order_hint[i] != priv->ref[i].order_hint)
1441                     priv->ref[i].valid = 0;
1442             }
1443         }
1444     }
1445
1446     if (current->frame_type == AV1_FRAME_KEY ||
1447         current->frame_type == AV1_FRAME_INTRA_ONLY) {
1448         CHECK(FUNC(frame_size)(ctx, rw, current));
1449         CHECK(FUNC(render_size)(ctx, rw, current));
1450
1451         if (current->allow_screen_content_tools &&
1452             priv->upscaled_width == priv->frame_width)
1453             flag(allow_intrabc);
1454         else
1455             infer(allow_intrabc, 0);
1456
1457     } else {
1458         if (!seq->enable_order_hint) {
1459             infer(frame_refs_short_signaling, 0);
1460         } else {
1461             flag(frame_refs_short_signaling);
1462             if (current->frame_refs_short_signaling) {
1463                 fb(3, last_frame_idx);
1464                 fb(3, golden_frame_idx);
1465                 CHECK(FUNC(set_frame_refs)(ctx, rw, current));
1466             }
1467         }
1468
1469         for (i = 0; i < AV1_REFS_PER_FRAME; i++) {
1470             if (!current->frame_refs_short_signaling)
1471                 fbs(3, ref_frame_idx[i], 1, i);
1472             if (seq->frame_id_numbers_present_flag) {
1473                 fbs(seq->delta_frame_id_length_minus_2 + 2,
1474                     delta_frame_id_minus1[i], 1, i);
1475             }
1476         }
1477
1478         if (current->frame_size_override_flag &&
1479             !current->error_resilient_mode) {
1480             CHECK(FUNC(frame_size_with_refs)(ctx, rw, current));
1481         } else {
1482             CHECK(FUNC(frame_size)(ctx, rw, current));
1483             CHECK(FUNC(render_size)(ctx, rw, current));
1484         }
1485
1486         if (current->force_integer_mv)
1487             infer(allow_high_precision_mv, 0);
1488         else
1489             flag(allow_high_precision_mv);
1490
1491         CHECK(FUNC(interpolation_filter)(ctx, rw, current));
1492
1493         flag(is_motion_mode_switchable);
1494
1495         if (current->error_resilient_mode ||
1496             !seq->enable_ref_frame_mvs)
1497             infer(use_ref_frame_mvs, 0);
1498         else
1499             flag(use_ref_frame_mvs);
1500
1501         infer(allow_intrabc, 0);
1502     }
1503
1504     if (!frame_is_intra) {
1505         // Derive reference frame sign biases.
1506     }
1507
1508     if (seq->reduced_still_picture_header || current->disable_cdf_update)
1509         infer(disable_frame_end_update_cdf, 1);
1510     else
1511         flag(disable_frame_end_update_cdf);
1512
1513     if (current->primary_ref_frame == AV1_PRIMARY_REF_NONE) {
1514         // Init non-coeff CDFs.
1515         // Setup past independence.
1516     } else {
1517         // Load CDF tables from previous frame.
1518         // Load params from previous frame.
1519     }
1520
1521     if (current->use_ref_frame_mvs) {
1522         // Perform motion field estimation process.
1523     }
1524
1525     CHECK(FUNC(tile_info)(ctx, rw, current));
1526
1527     CHECK(FUNC(quantization_params)(ctx, rw, current));
1528
1529     CHECK(FUNC(segmentation_params)(ctx, rw, current));
1530
1531     CHECK(FUNC(delta_q_params)(ctx, rw, current));
1532
1533     CHECK(FUNC(delta_lf_params)(ctx, rw, current));
1534
1535     // Init coeff CDFs / load previous segments.
1536
1537     priv->coded_lossless = 1;
1538     for (i = 0; i < AV1_MAX_SEGMENTS; i++) {
1539         int qindex;
1540         if (current->feature_enabled[i][AV1_SEG_LVL_ALT_Q]) {
1541             qindex = (current->base_q_idx +
1542                       current->feature_value[i][AV1_SEG_LVL_ALT_Q]);
1543         } else {
1544             qindex = current->base_q_idx;
1545         }
1546         qindex = av_clip_uintp2(qindex, 8);
1547
1548         if (qindex                || current->delta_q_y_dc ||
1549             current->delta_q_u_ac || current->delta_q_u_dc ||
1550             current->delta_q_v_ac || current->delta_q_v_dc) {
1551             priv->coded_lossless = 0;
1552         }
1553     }
1554     priv->all_lossless = priv->coded_lossless &&
1555         priv->frame_width == priv->upscaled_width;
1556
1557     CHECK(FUNC(loop_filter_params)(ctx, rw, current));
1558
1559     CHECK(FUNC(cdef_params)(ctx, rw, current));
1560
1561     CHECK(FUNC(lr_params)(ctx, rw, current));
1562
1563     CHECK(FUNC(read_tx_mode)(ctx, rw, current));
1564
1565     CHECK(FUNC(frame_reference_mode)(ctx, rw, current));
1566
1567     CHECK(FUNC(skip_mode_params)(ctx, rw, current));
1568
1569     if (frame_is_intra || current->error_resilient_mode ||
1570         !seq->enable_warped_motion)
1571         infer(allow_warped_motion, 0);
1572     else
1573         flag(allow_warped_motion);
1574
1575     flag(reduced_tx_set);
1576
1577     CHECK(FUNC(global_motion_params)(ctx, rw, current));
1578
1579     CHECK(FUNC(film_grain_params)(ctx, rw, current));
1580
1581     av_log(ctx->log_ctx, AV_LOG_DEBUG, "Frame %d:  size %dx%d  "
1582            "upscaled %d  render %dx%d  subsample %dx%d  "
1583            "bitdepth %d  tiles %dx%d.\n", priv->order_hint,
1584            priv->frame_width, priv->frame_height, priv->upscaled_width,
1585            priv->render_width, priv->render_height,
1586            seq->color_config.subsampling_x + 1,
1587            seq->color_config.subsampling_y + 1, priv->bit_depth,
1588            priv->tile_rows, priv->tile_cols);
1589
1590 update_refs:
1591     for (i = 0; i < AV1_NUM_REF_FRAMES; i++) {
1592         if (current->refresh_frame_flags & (1 << i)) {
1593             priv->ref[i] = (AV1ReferenceFrameState) {
1594                 .valid          = 1,
1595                 .frame_id       = current->current_frame_id,
1596                 .upscaled_width = priv->upscaled_width,
1597                 .frame_width    = priv->frame_width,
1598                 .frame_height   = priv->frame_height,
1599                 .render_width   = priv->render_width,
1600                 .render_height  = priv->render_height,
1601                 .frame_type     = current->frame_type,
1602                 .subsampling_x  = seq->color_config.subsampling_x,
1603                 .subsampling_y  = seq->color_config.subsampling_y,
1604                 .bit_depth      = priv->bit_depth,
1605                 .order_hint     = priv->order_hint,
1606             };
1607         }
1608     }
1609
1610     return 0;
1611 }
1612
1613 static int FUNC(frame_header_obu)(CodedBitstreamContext *ctx, RWContext *rw,
1614                                   AV1RawFrameHeader *current, int redundant,
1615                                   AVBufferRef *rw_buffer_ref)
1616 {
1617     CodedBitstreamAV1Context *priv = ctx->priv_data;
1618     int start_pos, fh_bits, fh_bytes, err;
1619     uint8_t *fh_start;
1620
1621     if (priv->seen_frame_header) {
1622         if (!redundant) {
1623             av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid repeated "
1624                    "frame header OBU.\n");
1625             return AVERROR_INVALIDDATA;
1626         } else {
1627             GetBitContext fh;
1628             size_t i, b;
1629             uint32_t val;
1630
1631             HEADER("Redundant Frame Header");
1632
1633             av_assert0(priv->frame_header_ref && priv->frame_header);
1634
1635             init_get_bits(&fh, priv->frame_header,
1636                           priv->frame_header_size);
1637             for (i = 0; i < priv->frame_header_size; i += 8) {
1638                 b = FFMIN(priv->frame_header_size - i, 8);
1639                 val = get_bits(&fh, b);
1640                 xf(b, frame_header_copy[i],
1641                    val, val, val, 1, i / 8);
1642             }
1643         }
1644     } else {
1645         if (redundant)
1646             HEADER("Redundant Frame Header (used as Frame Header)");
1647         else
1648             HEADER("Frame Header");
1649
1650 #ifdef READ
1651         start_pos = get_bits_count(rw);
1652 #else
1653         start_pos = put_bits_count(rw);
1654 #endif
1655
1656         CHECK(FUNC(uncompressed_header)(ctx, rw, current));
1657
1658         if (current->show_existing_frame) {
1659             priv->seen_frame_header = 0;
1660         } else {
1661             priv->seen_frame_header = 1;
1662
1663             av_buffer_unref(&priv->frame_header_ref);
1664
1665 #ifdef READ
1666             fh_bits  = get_bits_count(rw) - start_pos;
1667             fh_start = (uint8_t*)rw->buffer + start_pos / 8;
1668 #else
1669             // Need to flush the bitwriter so that we can copy its output,
1670             // but use a copy so we don't affect the caller's structure.
1671             {
1672                 PutBitContext tmp = *rw;
1673                 flush_put_bits(&tmp);
1674             }
1675
1676             fh_bits  = put_bits_count(rw) - start_pos;
1677             fh_start = rw->buf + start_pos / 8;
1678 #endif
1679             fh_bytes = (fh_bits + 7) / 8;
1680
1681             priv->frame_header_size = fh_bits;
1682
1683             if (rw_buffer_ref) {
1684                 priv->frame_header_ref = av_buffer_ref(rw_buffer_ref);
1685                 if (!priv->frame_header_ref)
1686                     return AVERROR(ENOMEM);
1687                 priv->frame_header = fh_start;
1688             } else {
1689                 priv->frame_header_ref =
1690                     av_buffer_alloc(fh_bytes + AV_INPUT_BUFFER_PADDING_SIZE);
1691                 if (!priv->frame_header_ref)
1692                     return AVERROR(ENOMEM);
1693                 priv->frame_header = priv->frame_header_ref->data;
1694                 memcpy(priv->frame_header, fh_start, fh_bytes);
1695             }
1696         }
1697     }
1698
1699     return 0;
1700 }
1701
1702 static int FUNC(tile_group_obu)(CodedBitstreamContext *ctx, RWContext *rw,
1703                                 AV1RawTileGroup *current)
1704 {
1705     CodedBitstreamAV1Context *priv = ctx->priv_data;
1706     int num_tiles, tile_bits;
1707     int err;
1708
1709     HEADER("Tile Group");
1710
1711     num_tiles = priv->tile_cols * priv->tile_rows;
1712     if (num_tiles > 1)
1713         flag(tile_start_and_end_present_flag);
1714     else
1715         infer(tile_start_and_end_present_flag, 0);
1716
1717     if (num_tiles == 1 || !current->tile_start_and_end_present_flag) {
1718         infer(tg_start, 0);
1719         infer(tg_end, num_tiles - 1);
1720     } else {
1721         tile_bits = cbs_av1_tile_log2(1, priv->tile_cols) +
1722                     cbs_av1_tile_log2(1, priv->tile_rows);
1723         fb(tile_bits, tg_start);
1724         fb(tile_bits, tg_end);
1725     }
1726
1727     CHECK(FUNC(byte_alignment)(ctx, rw));
1728
1729     // Reset header for next frame.
1730     if (current->tg_end == num_tiles - 1)
1731         priv->seen_frame_header = 0;
1732
1733     // Tile data follows.
1734
1735     return 0;
1736 }
1737
1738 static int FUNC(frame_obu)(CodedBitstreamContext *ctx, RWContext *rw,
1739                            AV1RawFrame *current,
1740                            AVBufferRef *rw_buffer_ref)
1741 {
1742     int err;
1743
1744     CHECK(FUNC(frame_header_obu)(ctx, rw, &current->header,
1745                                  0, rw_buffer_ref));
1746
1747     CHECK(FUNC(byte_alignment)(ctx, rw));
1748
1749     CHECK(FUNC(tile_group_obu)(ctx, rw, &current->tile_group));
1750
1751     return 0;
1752 }
1753
1754 static int FUNC(tile_list_obu)(CodedBitstreamContext *ctx, RWContext *rw,
1755                                AV1RawTileList *current)
1756 {
1757     int err;
1758
1759     fb(8, output_frame_width_in_tiles_minus_1);
1760     fb(8, output_frame_height_in_tiles_minus_1);
1761
1762     fb(16, tile_count_minus_1);
1763
1764     // Tile data follows.
1765
1766     return 0;
1767 }
1768
1769 static int FUNC(metadata_hdr_cll)(CodedBitstreamContext *ctx, RWContext *rw,
1770                                   AV1RawMetadataHDRCLL *current)
1771 {
1772     int err;
1773
1774     fb(16, max_cll);
1775     fb(16, max_fall);
1776
1777     return 0;
1778 }
1779
1780 static int FUNC(metadata_hdr_mdcv)(CodedBitstreamContext *ctx, RWContext *rw,
1781                                    AV1RawMetadataHDRMDCV *current)
1782 {
1783     int err, i;
1784
1785     for (i = 0; i < 3; i++) {
1786         fbs(16, primary_chromaticity_x[i], 1, i);
1787         fbs(16, primary_chromaticity_y[i], 1, i);
1788     }
1789
1790     fb(16, white_point_chromaticity_x);
1791     fb(16, white_point_chromaticity_y);
1792
1793     fc(32, luminance_max, 1, MAX_UINT_BITS(32));
1794     // luminance_min must be lower than luminance_max. Convert luminance_max from
1795     // 24.8 fixed point to 18.14 fixed point in order to compare them.
1796     fc(32, luminance_min, 0, FFMIN(((uint64_t)current->luminance_max << 6) - 1,
1797                                    MAX_UINT_BITS(32)));
1798
1799     return 0;
1800 }
1801
1802 static int FUNC(scalability_structure)(CodedBitstreamContext *ctx, RWContext *rw,
1803                                        AV1RawMetadataScalability *current)
1804 {
1805     CodedBitstreamAV1Context *priv = ctx->priv_data;
1806     const AV1RawSequenceHeader *seq;
1807     int err, i, j;
1808
1809     if (!priv->sequence_header) {
1810         av_log(ctx->log_ctx, AV_LOG_ERROR, "No sequence header available: "
1811                "unable to parse scalability metadata.\n");
1812         return AVERROR_INVALIDDATA;
1813     }
1814     seq = priv->sequence_header;
1815
1816     fb(2, spatial_layers_cnt_minus_1);
1817     flag(spatial_layer_dimensions_present_flag);
1818     flag(spatial_layer_description_present_flag);
1819     flag(temporal_group_description_present_flag);
1820     fc(3, scalability_structure_reserved_3bits, 0, 0);
1821     if (current->spatial_layer_dimensions_present_flag) {
1822         for (i = 0; i <= current->spatial_layers_cnt_minus_1; i++) {
1823             fcs(16, spatial_layer_max_width[i],
1824                 0, seq->max_frame_width_minus_1 + 1, 1, i);
1825             fcs(16, spatial_layer_max_height[i],
1826                 0, seq->max_frame_height_minus_1 + 1, 1, i);
1827         }
1828     }
1829     if (current->spatial_layer_description_present_flag) {
1830         for (i = 0; i <= current->spatial_layers_cnt_minus_1; i++)
1831             fbs(8, spatial_layer_ref_id[i], 1, i);
1832     }
1833     if (current->temporal_group_description_present_flag) {
1834         fb(8, temporal_group_size);
1835         for (i = 0; i < current->temporal_group_size; i++) {
1836             fbs(3, temporal_group_temporal_id[i], 1, i);
1837             flags(temporal_group_temporal_switching_up_point_flag[i], 1, i);
1838             flags(temporal_group_spatial_switching_up_point_flag[i], 1, i);
1839             fbs(3, temporal_group_ref_cnt[i], 1, i);
1840             for (j = 0; j < current->temporal_group_ref_cnt[i]; j++) {
1841                 fbs(8, temporal_group_ref_pic_diff[i][j], 2, i, j);
1842             }
1843         }
1844     }
1845
1846     return 0;
1847 }
1848
1849 static int FUNC(metadata_scalability)(CodedBitstreamContext *ctx, RWContext *rw,
1850                                       AV1RawMetadataScalability *current)
1851 {
1852     int err;
1853
1854     fb(8, scalability_mode_idc);
1855
1856     if (current->scalability_mode_idc == AV1_SCALABILITY_SS)
1857         CHECK(FUNC(scalability_structure)(ctx, rw, current));
1858
1859     return 0;
1860 }
1861
1862 static int FUNC(metadata_itut_t35)(CodedBitstreamContext *ctx, RWContext *rw,
1863                                    AV1RawMetadataITUTT35 *current)
1864 {
1865     int err;
1866     size_t i;
1867
1868     fb(8, itu_t_t35_country_code);
1869     if (current->itu_t_t35_country_code == 0xff)
1870         fb(8, itu_t_t35_country_code_extension_byte);
1871
1872 #ifdef READ
1873     // The payload runs up to the start of the trailing bits, but there might
1874     // be arbitrarily many trailing zeroes so we need to read through twice.
1875     current->payload_size = cbs_av1_get_payload_bytes_left(rw);
1876
1877     current->payload_ref = av_buffer_alloc(current->payload_size);
1878     if (!current->payload_ref)
1879         return AVERROR(ENOMEM);
1880     current->payload = current->payload_ref->data;
1881 #endif
1882
1883     for (i = 0; i < current->payload_size; i++)
1884         xf(8, itu_t_t35_payload_bytes[i], current->payload[i],
1885            0x00, 0xff, 1, i);
1886
1887     return 0;
1888 }
1889
1890 static int FUNC(metadata_timecode)(CodedBitstreamContext *ctx, RWContext *rw,
1891                                    AV1RawMetadataTimecode *current)
1892 {
1893     int err;
1894
1895     fb(5, counting_type);
1896     flag(full_timestamp_flag);
1897     flag(discontinuity_flag);
1898     flag(cnt_dropped_flag);
1899     fb(9, n_frames);
1900
1901     if (current->full_timestamp_flag) {
1902         fc(6, seconds_value, 0, 59);
1903         fc(6, minutes_value, 0, 59);
1904         fc(5, hours_value,   0, 23);
1905     } else {
1906         flag(seconds_flag);
1907         if (current->seconds_flag) {
1908             fc(6, seconds_value, 0, 59);
1909             flag(minutes_flag);
1910             if (current->minutes_flag) {
1911                 fc(6, minutes_value, 0, 59);
1912                 flag(hours_flag);
1913                 if (current->hours_flag)
1914                     fc(5, hours_value, 0, 23);
1915             }
1916         }
1917     }
1918
1919     fb(5, time_offset_length);
1920     if (current->time_offset_length > 0)
1921         fb(current->time_offset_length, time_offset_value);
1922     else
1923         infer(time_offset_length, 0);
1924
1925     return 0;
1926 }
1927
1928 static int FUNC(metadata_obu)(CodedBitstreamContext *ctx, RWContext *rw,
1929                               AV1RawMetadata *current)
1930 {
1931     int err;
1932
1933     leb128(metadata_type);
1934
1935     switch (current->metadata_type) {
1936     case AV1_METADATA_TYPE_HDR_CLL:
1937         CHECK(FUNC(metadata_hdr_cll)(ctx, rw, &current->metadata.hdr_cll));
1938         break;
1939     case AV1_METADATA_TYPE_HDR_MDCV:
1940         CHECK(FUNC(metadata_hdr_mdcv)(ctx, rw, &current->metadata.hdr_mdcv));
1941         break;
1942     case AV1_METADATA_TYPE_SCALABILITY:
1943         CHECK(FUNC(metadata_scalability)(ctx, rw, &current->metadata.scalability));
1944         break;
1945     case AV1_METADATA_TYPE_ITUT_T35:
1946         CHECK(FUNC(metadata_itut_t35)(ctx, rw, &current->metadata.itut_t35));
1947         break;
1948     case AV1_METADATA_TYPE_TIMECODE:
1949         CHECK(FUNC(metadata_timecode)(ctx, rw, &current->metadata.timecode));
1950         break;
1951     default:
1952         // Unknown metadata type.
1953         return AVERROR_PATCHWELCOME;
1954     }
1955
1956     return 0;
1957 }
1958
1959 static int FUNC(padding_obu)(CodedBitstreamContext *ctx, RWContext *rw,
1960                              AV1RawPadding *current)
1961 {
1962     int i, err;
1963
1964     HEADER("Padding");
1965
1966 #ifdef READ
1967     // The payload runs up to the start of the trailing bits, but there might
1968     // be arbitrarily many trailing zeroes so we need to read through twice.
1969     current->payload_size = cbs_av1_get_payload_bytes_left(rw);
1970
1971     current->payload_ref = av_buffer_alloc(current->payload_size);
1972     if (!current->payload_ref)
1973         return AVERROR(ENOMEM);
1974     current->payload = current->payload_ref->data;
1975 #endif
1976
1977     for (i = 0; i < current->payload_size; i++)
1978         xf(8, obu_padding_byte[i], current->payload[i], 0x00, 0xff, 1, i);
1979
1980     return 0;
1981 }