| /* |
| * Copyright (c) 2017, Alliance for Open Media. All rights reserved |
| * |
| * This source code is subject to the terms of the BSD 2 Clause License and |
| * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License |
| * was not distributed with this source code in the LICENSE file, you can |
| * obtain it at www.aomedia.org/license/software. If the Alliance for Open |
| * Media Patent License 1.0 was not distributed with this source code in the |
| * PATENTS file, you can obtain it at www.aomedia.org/license/patent. |
| */ |
| |
| #include <assert.h> |
| |
| #include "./aom_config.h" |
| |
| #include "aom/aom_codec.h" |
| #include "aom_dsp/bitreader_buffer.h" |
| #include "aom_ports/mem_ops.h" |
| |
| #include "av1/common/common.h" |
| #include "av1/decoder/decoder.h" |
| #include "av1/decoder/decodeframe.h" |
| #include "av1/decoder/obu.h" |
| |
| // Picture prediction structures (0-12 are predefined) in scalability metadata. |
| typedef enum { |
| SCALABILITY_L1T2 = 0, |
| SCALABILITY_L1T3 = 1, |
| SCALABILITY_L2T1 = 2, |
| SCALABILITY_L2T2 = 3, |
| SCALABILITY_L2T3 = 4, |
| SCALABILITY_S2T1 = 5, |
| SCALABILITY_S2T2 = 6, |
| SCALABILITY_S2T3 = 7, |
| SCALABILITY_L2T1h = 8, |
| SCALABILITY_L2T2h = 9, |
| SCALABILITY_L2T3h = 10, |
| SCALABILITY_S2T1h = 11, |
| SCALABILITY_S2T2h = 12, |
| SCALABILITY_S2T3h = 13, |
| SCALABILITY_SS = 14 |
| } SCALABILITY_STRUCTURES; |
| |
| // Returns 1 when OBU type is valid, and 0 otherwise. |
| static int valid_obu_type(int obu_type) { |
| int valid_type = 0; |
| switch (obu_type) { |
| case OBU_SEQUENCE_HEADER: |
| case OBU_TEMPORAL_DELIMITER: |
| case OBU_FRAME_HEADER: |
| case OBU_REDUNDANT_FRAME_HEADER: |
| case OBU_FRAME: |
| case OBU_TILE_GROUP: |
| case OBU_METADATA: |
| case OBU_PADDING: valid_type = 1; break; |
| default: break; |
| } |
| return valid_type; |
| } |
| |
| // Parses OBU header and stores values in 'header'. |
| static aom_codec_err_t read_obu_header(struct aom_read_bit_buffer *rb, |
| int is_annexb, ObuHeader *header) { |
| if (!rb || !header) return AOM_CODEC_INVALID_PARAM; |
| |
| const ptrdiff_t bit_buffer_byte_length = rb->bit_buffer_end - rb->bit_buffer; |
| if (bit_buffer_byte_length < 1) return AOM_CODEC_CORRUPT_FRAME; |
| |
| header->size = 1; |
| |
| if (aom_rb_read_bit(rb) != 0) { |
| // Forbidden bit. Must not be set. |
| return AOM_CODEC_CORRUPT_FRAME; |
| } |
| |
| header->type = (OBU_TYPE)aom_rb_read_literal(rb, 4); |
| |
| if (!valid_obu_type(header->type)) return AOM_CODEC_CORRUPT_FRAME; |
| |
| header->has_extension = aom_rb_read_bit(rb); |
| header->has_length_field = aom_rb_read_bit(rb); |
| |
| if (!header->has_length_field && !is_annexb) { |
| // section 5 obu streams must have length field set. |
| return AOM_CODEC_UNSUP_BITSTREAM; |
| } |
| |
| aom_rb_read_bit(rb); // reserved |
| |
| if (header->has_extension) { |
| if (bit_buffer_byte_length == 1) return AOM_CODEC_CORRUPT_FRAME; |
| |
| header->size += 1; |
| header->temporal_layer_id = aom_rb_read_literal(rb, 3); |
| header->spatial_layer_id = aom_rb_read_literal(rb, 2); |
| aom_rb_read_literal(rb, 3); // reserved |
| } |
| |
| return AOM_CODEC_OK; |
| } |
| |
| aom_codec_err_t aom_read_obu_header(uint8_t *buffer, size_t buffer_length, |
| size_t *consumed, ObuHeader *header, |
| int is_annexb) { |
| if (buffer_length < 1 || !consumed || !header) return AOM_CODEC_INVALID_PARAM; |
| |
| // TODO(tomfinegan): Set the error handler here and throughout this file, and |
| // confirm parsing work done via aom_read_bit_buffer is successful. |
| struct aom_read_bit_buffer rb = { buffer, buffer + buffer_length, 0, NULL, |
| NULL }; |
| aom_codec_err_t parse_result = read_obu_header(&rb, is_annexb, header); |
| if (parse_result == AOM_CODEC_OK) *consumed = header->size; |
| return parse_result; |
| } |
| |
| static int is_obu_in_current_operating_point(AV1Decoder *pbi, |
| ObuHeader obu_header) { |
| if (!pbi->current_operating_point) { |
| return 1; |
| } |
| |
| if ((pbi->current_operating_point >> obu_header.temporal_layer_id) & 0x1 && |
| (pbi->current_operating_point >> (obu_header.spatial_layer_id + 8)) & |
| 0x1) { |
| return 1; |
| } |
| return 0; |
| } |
| |
| static uint32_t read_temporal_delimiter_obu() { return 0; } |
| |
| static BitstreamLevel read_bitstream_level(struct aom_read_bit_buffer *rb) { |
| BitstreamLevel bl; |
| bl.major = aom_rb_read_literal(rb, LEVEL_MAJOR_BITS) + LEVEL_MAJOR_MIN; |
| bl.minor = aom_rb_read_literal(rb, LEVEL_MINOR_BITS); |
| return bl; |
| } |
| |
| static uint32_t read_sequence_header_obu(AV1Decoder *pbi, |
| struct aom_read_bit_buffer *rb) { |
| AV1_COMMON *const cm = &pbi->common; |
| uint32_t saved_bit_offset = rb->bit_offset; |
| |
| cm->profile = av1_read_profile(rb); |
| |
| SequenceHeader *seq_params = &cm->seq_params; |
| |
| // Still picture or not |
| seq_params->still_picture = aom_rb_read_bit(rb); |
| seq_params->reduced_still_picture_hdr = aom_rb_read_bit(rb); |
| // Video must have reduced_still_picture_hdr = 0 |
| if (!cm->seq_params.still_picture && |
| cm->seq_params.reduced_still_picture_hdr) { |
| return AOM_CODEC_UNSUP_BITSTREAM; |
| } |
| |
| if (seq_params->reduced_still_picture_hdr) { |
| seq_params->operating_point_idc[0] = 0; |
| seq_params->level[0] = read_bitstream_level(rb); |
| if (seq_params->level[0].major > LEVEL_MAJOR_MAX) |
| return AOM_CODEC_UNSUP_BITSTREAM; |
| seq_params->decoder_rate_model_param_present_flag[0] = 0; |
| } else { |
| uint8_t operating_points_minus1_cnt = |
| aom_rb_read_literal(rb, OP_POINTS_MINUS1_BITS); |
| for (int i = 0; i < operating_points_minus1_cnt + 1; i++) { |
| seq_params->operating_point_idc[i] = |
| aom_rb_read_literal(rb, OP_POINTS_IDC_BITS); |
| seq_params->level[i] = read_bitstream_level(rb); |
| if (seq_params->level[i].major > LEVEL_MAJOR_MAX) |
| return AOM_CODEC_UNSUP_BITSTREAM; |
| #if !CONFIG_BUFFER_MODEL |
| seq_params->decoder_rate_model_param_present_flag[i] = |
| aom_rb_read_literal(rb, 1); |
| if (seq_params->decoder_rate_model_param_present_flag[i]) { |
| seq_params->decode_to_display_rate_ratio[i] = |
| aom_rb_read_literal(rb, 12); |
| seq_params->initial_display_delay[i] = aom_rb_read_literal(rb, 24); |
| seq_params->extra_frame_buffers[i] = aom_rb_read_literal(rb, 4); |
| } |
| #endif |
| } |
| } |
| // This decoder supports all levels. Choose operating point provided by |
| // external means |
| int operating_point = pbi->operating_point; |
| if (operating_point < 0 || |
| operating_point >= pbi->common.enhancement_layers_cnt) |
| operating_point = 0; |
| pbi->current_operating_point = |
| seq_params->operating_point_idc[operating_point]; |
| |
| read_sequence_header(cm, rb); |
| |
| av1_read_bitdepth_colorspace_sampling(cm, rb, pbi->allow_lowbitdepth); |
| |
| #if !CONFIG_BUFFER_MODEL |
| if (!seq_params->reduced_still_picture_hdr) |
| av1_read_timing_info_header(cm, rb); |
| else |
| cm->timing_info_present = 0; |
| #else |
| if (!seq_params->reduced_still_picture_hdr) |
| cm->timing_info_present = aom_rb_read_bit(rb); // timing info present flag |
| else |
| cm->timing_info_present = 0; |
| |
| if (cm->timing_info_present) { |
| av1_read_timing_info_header(cm, rb); |
| |
| cm->decoder_model_info_present_flag = aom_rb_read_bit(rb); |
| if (cm->decoder_model_info_present_flag) |
| av1_read_decoder_model_info(cm, rb); |
| } else { |
| cm->decoder_model_info_present_flag = 0; |
| } |
| int operating_points_decoder_model_present = aom_rb_read_bit(rb); |
| if (operating_points_decoder_model_present) { |
| cm->operating_points_decoder_model_cnt = aom_rb_read_literal(rb, 5) + 1; |
| } else { |
| cm->operating_points_decoder_model_cnt = 0; |
| } |
| for (int op_num = 0; op_num < cm->operating_points_decoder_model_cnt; |
| ++op_num) { |
| cm->op_params[op_num].decoder_model_operating_point_idc = |
| aom_rb_read_literal(rb, 12); |
| cm->op_params[op_num].display_model_param_present_flag = |
| aom_rb_read_bit(rb); |
| if (cm->op_params[op_num].display_model_param_present_flag) { |
| cm->op_params[op_num].initial_display_delay = |
| aom_rb_read_literal(rb, 4) + 1; |
| if (cm->op_params[op_num].initial_display_delay > 10) |
| aom_internal_error( |
| &cm->error, AOM_CODEC_UNSUP_BITSTREAM, |
| "AV1 does not support more than 10 decoded frames delay"); |
| } |
| if (cm->decoder_model_info_present_flag) { |
| cm->op_params[op_num].decoder_model_param_present_flag = |
| aom_rb_read_bit(rb); |
| if (cm->op_params[op_num].decoder_model_param_present_flag) |
| av1_read_op_parameters_info(cm, rb, op_num); |
| } |
| } |
| #endif |
| |
| cm->film_grain_params_present = aom_rb_read_bit(rb); |
| |
| av1_check_trailing_bits(pbi, rb); |
| |
| pbi->sequence_header_ready = 1; |
| |
| return ((rb->bit_offset - saved_bit_offset + 7) >> 3); |
| } |
| |
| static uint32_t read_frame_header_obu(AV1Decoder *pbi, |
| struct aom_read_bit_buffer *rb, |
| const uint8_t *data, |
| const uint8_t **p_data_end, |
| int trailing_bits_present) { |
| av1_decode_frame_headers_and_setup(pbi, rb, data, p_data_end, |
| trailing_bits_present); |
| return (uint32_t)(pbi->uncomp_hdr_size); |
| } |
| |
| static int32_t read_tile_group_header(AV1Decoder *pbi, |
| struct aom_read_bit_buffer *rb, |
| int *startTile, int *endTile, |
| int tile_start_implicit) { |
| AV1_COMMON *const cm = &pbi->common; |
| uint32_t saved_bit_offset = rb->bit_offset; |
| int tile_start_and_end_present_flag = 0; |
| const int num_tiles = pbi->common.tile_rows * pbi->common.tile_cols; |
| |
| if (!pbi->common.large_scale_tile && num_tiles > 1) { |
| tile_start_and_end_present_flag = aom_rb_read_bit(rb); |
| } |
| if (pbi->common.large_scale_tile || num_tiles == 1 || |
| !tile_start_and_end_present_flag) { |
| *startTile = 0; |
| *endTile = num_tiles - 1; |
| return ((rb->bit_offset - saved_bit_offset + 7) >> 3); |
| } |
| if (tile_start_implicit && tile_start_and_end_present_flag) { |
| aom_internal_error( |
| &cm->error, AOM_CODEC_UNSUP_BITSTREAM, |
| "For OBU_FRAME type obu tile_start_and_end_present_flag must be 0"); |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| *startTile = aom_rb_read_literal(rb, cm->log2_tile_rows + cm->log2_tile_cols); |
| *endTile = aom_rb_read_literal(rb, cm->log2_tile_rows + cm->log2_tile_cols); |
| |
| return ((rb->bit_offset - saved_bit_offset + 7) >> 3); |
| } |
| |
| static uint32_t read_one_tile_group_obu( |
| AV1Decoder *pbi, struct aom_read_bit_buffer *rb, int is_first_tg, |
| const uint8_t *data, const uint8_t *data_end, const uint8_t **p_data_end, |
| int *is_last_tg, int tile_start_implicit) { |
| AV1_COMMON *const cm = &pbi->common; |
| int startTile, endTile; |
| int32_t header_size, tg_payload_size; |
| |
| header_size = read_tile_group_header(pbi, rb, &startTile, &endTile, |
| tile_start_implicit); |
| if (header_size == -1) return 0; |
| if (startTile > endTile) return header_size; |
| data += header_size; |
| av1_decode_tg_tiles_and_wrapup(pbi, data, data_end, p_data_end, startTile, |
| endTile, is_first_tg); |
| |
| tg_payload_size = (uint32_t)(*p_data_end - data); |
| |
| // TODO(shan): For now, assume all tile groups received in order |
| *is_last_tg = endTile == cm->tile_rows * cm->tile_cols - 1; |
| return header_size + tg_payload_size; |
| } |
| |
| static void read_metadata_itut_t35(const uint8_t *data, size_t sz) { |
| struct aom_read_bit_buffer rb = { data, data + sz, 0, NULL, NULL }; |
| for (size_t i = 0; i < sz; i++) { |
| aom_rb_read_literal(&rb, 8); |
| } |
| } |
| |
| static void read_metadata_hdr_cll(const uint8_t *data, size_t sz) { |
| struct aom_read_bit_buffer rb = { data, data + sz, 0, NULL, NULL }; |
| aom_rb_read_literal(&rb, 16); // max_cll |
| aom_rb_read_literal(&rb, 16); // max_fall |
| } |
| |
| static void read_metadata_hdr_mdcv(const uint8_t *data, size_t sz) { |
| struct aom_read_bit_buffer rb = { data, data + sz, 0, NULL, NULL }; |
| for (int i = 0; i < 3; i++) { |
| aom_rb_read_literal(&rb, 16); // primary_i_chromaticity_x |
| aom_rb_read_literal(&rb, 16); // primary_i_chromaticity_y |
| } |
| |
| aom_rb_read_literal(&rb, 16); // white_point_chromaticity_x |
| aom_rb_read_literal(&rb, 16); // white_point_chromaticity_y |
| |
| aom_rb_read_unsigned_literal(&rb, 32); // luminance_max |
| aom_rb_read_unsigned_literal(&rb, 32); // luminance_min |
| } |
| |
| static void scalability_structure(struct aom_read_bit_buffer *rb) { |
| int spatial_layers_cnt = aom_rb_read_literal(rb, 2); |
| int spatial_layer_dimensions_present_flag = aom_rb_read_literal(rb, 1); |
| int spatial_layer_description_present_flag = aom_rb_read_literal(rb, 1); |
| int temporal_group_description_present_flag = aom_rb_read_literal(rb, 1); |
| aom_rb_read_literal(rb, 3); // reserved |
| |
| if (spatial_layer_dimensions_present_flag) { |
| int i; |
| for (i = 0; i < spatial_layers_cnt + 1; i++) { |
| aom_rb_read_literal(rb, 16); |
| aom_rb_read_literal(rb, 16); |
| } |
| } |
| if (spatial_layer_description_present_flag) { |
| int i; |
| for (i = 0; i < spatial_layers_cnt + 1; i++) { |
| aom_rb_read_literal(rb, 8); |
| } |
| } |
| if (temporal_group_description_present_flag) { |
| int i, j, temporal_group_size; |
| temporal_group_size = aom_rb_read_literal(rb, 8); |
| for (i = 0; i < temporal_group_size; i++) { |
| aom_rb_read_literal(rb, 3); |
| aom_rb_read_literal(rb, 1); |
| aom_rb_read_literal(rb, 1); |
| int temporal_group_ref_cnt = aom_rb_read_literal(rb, 3); |
| for (j = 0; j < temporal_group_ref_cnt; j++) { |
| aom_rb_read_literal(rb, 8); |
| } |
| } |
| } |
| } |
| |
| static void read_metadata_scalability(const uint8_t *data, size_t sz) { |
| struct aom_read_bit_buffer rb = { data, data + sz, 0, NULL, NULL }; |
| int scalability_mode_idc = aom_rb_read_literal(&rb, 8); |
| if (scalability_mode_idc == SCALABILITY_SS) { |
| scalability_structure(&rb); |
| } |
| } |
| |
| static void read_metadata_timecode(const uint8_t *data, size_t sz) { |
| struct aom_read_bit_buffer rb = { data, data + sz, 0, NULL, NULL }; |
| aom_rb_read_literal(&rb, 5); // counting_type f(5) |
| int full_timestamp_flag = aom_rb_read_bit(&rb); // full_timestamp_flag f(1) |
| aom_rb_read_bit(&rb); // discontinuity_flag (f1) |
| aom_rb_read_bit(&rb); // cnt_dropped_flag f(1) |
| aom_rb_read_literal(&rb, 9); // n_frames f(9) |
| if (full_timestamp_flag) { |
| aom_rb_read_literal(&rb, 6); // seconds_value f(6) |
| aom_rb_read_literal(&rb, 6); // minutes_value f(6) |
| aom_rb_read_literal(&rb, 5); // hours_value f(5) |
| } else { |
| int seconds_flag = aom_rb_read_bit(&rb); // seconds_flag f(1) |
| if (seconds_flag) { |
| aom_rb_read_literal(&rb, 6); // seconds_value f(6) |
| int minutes_flag = aom_rb_read_bit(&rb); // minutes_flag f(1) |
| if (minutes_flag) { |
| aom_rb_read_literal(&rb, 6); // minutes_value f(6) |
| int hours_flag = aom_rb_read_bit(&rb); // hours_flag f(1) |
| if (hours_flag) { |
| aom_rb_read_literal(&rb, 5); // hours_value f(5) |
| } |
| } |
| } |
| } |
| // time_offset_length f(5) |
| int time_offset_length = aom_rb_read_literal(&rb, 5); |
| if (time_offset_length) { |
| aom_rb_read_literal(&rb, time_offset_length); // f(time_offset_length) |
| } |
| } |
| |
| static size_t read_metadata(const uint8_t *data, size_t sz) { |
| size_t type_length; |
| uint64_t type_value; |
| OBU_METADATA_TYPE metadata_type; |
| if (aom_uleb_decode(data, sz, &type_value, &type_length) < 0) { |
| return sz; |
| } |
| metadata_type = (OBU_METADATA_TYPE)type_value; |
| if (metadata_type == OBU_METADATA_TYPE_ITUT_T35) { |
| read_metadata_itut_t35(data + type_length, sz - type_length); |
| } else if (metadata_type == OBU_METADATA_TYPE_HDR_CLL) { |
| read_metadata_hdr_cll(data + type_length, sz - type_length); |
| } else if (metadata_type == OBU_METADATA_TYPE_HDR_MDCV) { |
| read_metadata_hdr_mdcv(data + type_length, sz - type_length); |
| } else if (metadata_type == OBU_METADATA_TYPE_SCALABILITY) { |
| read_metadata_scalability(data + type_length, sz - type_length); |
| } else if (metadata_type == OBU_METADATA_TYPE_TIMECODE) { |
| read_metadata_timecode(data + type_length, sz - type_length); |
| } |
| |
| return sz; |
| } |
| |
| static aom_codec_err_t read_obu_size(const uint8_t *data, |
| size_t bytes_available, |
| size_t *const obu_size, |
| size_t *const length_field_size) { |
| uint64_t u_obu_size = 0; |
| if (aom_uleb_decode(data, bytes_available, &u_obu_size, length_field_size) != |
| 0) { |
| return AOM_CODEC_CORRUPT_FRAME; |
| } |
| |
| if (u_obu_size > UINT32_MAX) return AOM_CODEC_CORRUPT_FRAME; |
| *obu_size = (size_t)u_obu_size; |
| return AOM_CODEC_OK; |
| } |
| |
| aom_codec_err_t aom_read_obu_header_and_size(const uint8_t *data, |
| size_t bytes_available, |
| int is_annexb, |
| ObuHeader *obu_header, |
| size_t *const payload_size, |
| size_t *const bytes_read) { |
| size_t length_field_size = 0, obu_size = 0; |
| aom_codec_err_t status; |
| |
| if (is_annexb) { |
| // Size field comes before the OBU header, and includes the OBU header |
| status = |
| read_obu_size(data, bytes_available, &obu_size, &length_field_size); |
| |
| if (status != AOM_CODEC_OK) return status; |
| } |
| |
| struct aom_read_bit_buffer rb = { data + length_field_size, |
| data + bytes_available, 0, NULL, NULL }; |
| |
| status = read_obu_header(&rb, is_annexb, obu_header); |
| if (status != AOM_CODEC_OK) return status; |
| |
| if (is_annexb) { |
| // Derive the payload size from the data we've already read |
| if (obu_size < obu_header->size) return AOM_CODEC_CORRUPT_FRAME; |
| |
| *payload_size = obu_size - obu_header->size; |
| } else { |
| // Size field comes after the OBU header, and is just the payload size |
| status = read_obu_size(data + obu_header->size, |
| bytes_available - obu_header->size, payload_size, |
| &length_field_size); |
| if (status != AOM_CODEC_OK) return status; |
| } |
| |
| *bytes_read = length_field_size + obu_header->size; |
| return AOM_CODEC_OK; |
| } |
| |
| void aom_decode_frame_from_obus(struct AV1Decoder *pbi, const uint8_t *data, |
| const uint8_t *data_end, |
| const uint8_t **p_data_end) { |
| AV1_COMMON *const cm = &pbi->common; |
| int frame_decoding_finished = 0; |
| int is_first_tg_obu_received = 1; |
| int frame_header_received = 0; |
| int frame_header_size = 0; |
| int seq_header_received = 0; |
| size_t seq_header_size = 0; |
| ObuHeader obu_header; |
| memset(&obu_header, 0, sizeof(obu_header)); |
| pbi->dropped_obus = 0; |
| |
| if (data_end < data) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| |
| // decode frame as a series of OBUs |
| while (!frame_decoding_finished && !cm->error.error_code) { |
| struct aom_read_bit_buffer rb; |
| size_t payload_size = 0; |
| size_t decoded_payload_size = 0; |
| size_t obu_payload_offset = 0; |
| size_t bytes_read = 0; |
| const size_t bytes_available = data_end - data; |
| |
| if (bytes_available == 0 && !frame_header_received) { |
| cm->error.error_code = AOM_CODEC_OK; |
| return; |
| } |
| |
| aom_codec_err_t status = |
| aom_read_obu_header_and_size(data, bytes_available, cm->is_annexb, |
| &obu_header, &payload_size, &bytes_read); |
| if (status != AOM_CODEC_OK) { |
| cm->error.error_code = status; |
| return; |
| } |
| |
| // Note: aom_read_obu_header_and_size() takes care of checking that this |
| // doesn't cause 'data' to advance past 'data_end'. |
| data += bytes_read; |
| |
| cm->temporal_layer_id = obu_header.temporal_layer_id; |
| cm->spatial_layer_id = obu_header.spatial_layer_id; |
| |
| if (obu_header.type != OBU_TEMPORAL_DELIMITER && |
| obu_header.type != OBU_SEQUENCE_HEADER && |
| obu_header.type != OBU_PADDING) { |
| // don't decode obu if it's not in current operating mode |
| if (!is_obu_in_current_operating_point(pbi, obu_header)) { |
| data += payload_size; |
| *p_data_end = data; |
| pbi->dropped_obus++; |
| continue; |
| } |
| } |
| |
| av1_init_read_bit_buffer(pbi, &rb, data, data_end); |
| |
| switch (obu_header.type) { |
| case OBU_TEMPORAL_DELIMITER: |
| decoded_payload_size = read_temporal_delimiter_obu(); |
| break; |
| case OBU_SEQUENCE_HEADER: |
| if (!seq_header_received) { |
| decoded_payload_size = read_sequence_header_obu(pbi, &rb); |
| seq_header_size = decoded_payload_size; |
| seq_header_received = 1; |
| } else { |
| // Seeing another sequence header, skip as all sequence headers |
| // are required to be identical. |
| if (payload_size != seq_header_size) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| decoded_payload_size = seq_header_size; |
| } |
| break; |
| case OBU_FRAME_HEADER: |
| case OBU_REDUNDANT_FRAME_HEADER: |
| case OBU_FRAME: |
| // Only decode first frame header received |
| if (!frame_header_received) { |
| pbi->dropped_obus = 0; |
| av1_init_read_bit_buffer(pbi, &rb, data, data_end); |
| frame_header_size = read_frame_header_obu( |
| pbi, &rb, data, p_data_end, obu_header.type != OBU_FRAME); |
| frame_header_received = 1; |
| } |
| decoded_payload_size = frame_header_size; |
| if (cm->show_existing_frame) { |
| frame_decoding_finished = 1; |
| break; |
| } |
| if (obu_header.type != OBU_FRAME) break; |
| obu_payload_offset = frame_header_size; |
| AOM_FALLTHROUGH_INTENDED; // fall through to read tile group. |
| case OBU_TILE_GROUP: |
| if (!frame_header_received) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| if (data_end < data + obu_payload_offset || |
| data_end < data + payload_size) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| decoded_payload_size += read_one_tile_group_obu( |
| pbi, &rb, is_first_tg_obu_received, data + obu_payload_offset, |
| data + payload_size, p_data_end, &frame_decoding_finished, |
| obu_header.type == OBU_FRAME); |
| is_first_tg_obu_received = 0; |
| break; |
| case OBU_METADATA: |
| if (data_end < data + payload_size) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| decoded_payload_size = read_metadata(data, payload_size); |
| break; |
| case OBU_PADDING: |
| default: |
| // Skip unrecognized OBUs |
| decoded_payload_size = payload_size; |
| break; |
| } |
| |
| // Check that the signalled OBU size matches the actual amount of data read |
| if (decoded_payload_size > payload_size) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| |
| if (data_end < data + payload_size) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| |
| // If there are extra padding bytes, they should all be zero |
| while (decoded_payload_size < payload_size) { |
| uint8_t padding_byte = data[decoded_payload_size++]; |
| if (padding_byte != 0) { |
| cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return; |
| } |
| } |
| |
| data += payload_size; |
| } |
| } |
