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