diff options
Diffstat (limited to 'media/libaom/src/av1/decoder/obu.c')
| -rw-r--r-- | media/libaom/src/av1/decoder/obu.c | 839 |
1 files changed, 839 insertions, 0 deletions
diff --git a/media/libaom/src/av1/decoder/obu.c b/media/libaom/src/av1/decoder/obu.c new file mode 100644 index 0000000000..44ecf818e7 --- /dev/null +++ b/media/libaom/src/av1/decoder/obu.c @@ -0,0 +1,839 @@ +/* + * 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 "config/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/common/obu_util.h" +#include "av1/common/timing.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; + +aom_codec_err_t aom_get_num_layers_from_operating_point_idc( + int operating_point_idc, unsigned int *number_spatial_layers, + unsigned int *number_temporal_layers) { + // derive number of spatial/temporal layers from operating_point_idc + + if (!number_spatial_layers || !number_temporal_layers) + return AOM_CODEC_INVALID_PARAM; + + if (operating_point_idc == 0) { + *number_temporal_layers = 1; + *number_spatial_layers = 1; + } else { + *number_spatial_layers = 0; + *number_temporal_layers = 0; + for (int j = 0; j < MAX_NUM_SPATIAL_LAYERS; j++) { + *number_spatial_layers += + (operating_point_idc >> (j + MAX_NUM_TEMPORAL_LAYERS)) & 0x1; + } + for (int j = 0; j < MAX_NUM_TEMPORAL_LAYERS; j++) { + *number_temporal_layers += (operating_point_idc >> j) & 0x1; + } + } + + return AOM_CODEC_OK; +} + +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 int byte_alignment(AV1_COMMON *const cm, + struct aom_read_bit_buffer *const rb) { + while (rb->bit_offset & 7) { + if (aom_rb_read_bit(rb)) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + } + return 0; +} + +static uint32_t read_temporal_delimiter_obu() { return 0; } + +// Returns a boolean that indicates success. +static int read_bitstream_level(BitstreamLevel *bl, + struct aom_read_bit_buffer *rb) { + const uint8_t seq_level_idx = aom_rb_read_literal(rb, LEVEL_BITS); + if (!is_valid_seq_level_idx(seq_level_idx)) return 0; + bl->major = (seq_level_idx >> LEVEL_MINOR_BITS) + LEVEL_MAJOR_MIN; + bl->minor = seq_level_idx & ((1 << LEVEL_MINOR_BITS) - 1); + return 1; +} + +// Returns whether two sequence headers are consistent with each other. +// TODO(huisu,wtc@google.com): make sure the code matches the spec exactly. +static int are_seq_headers_consistent(const SequenceHeader *seq_params_old, + const SequenceHeader *seq_params_new) { + return !memcmp(seq_params_old, seq_params_new, sizeof(SequenceHeader)); +} + +// On success, sets pbi->sequence_header_ready to 1 and returns the number of +// bytes read from 'rb'. +// On failure, sets pbi->common.error.error_code and returns 0. +static uint32_t read_sequence_header_obu(AV1Decoder *pbi, + struct aom_read_bit_buffer *rb) { + AV1_COMMON *const cm = &pbi->common; + const uint32_t saved_bit_offset = rb->bit_offset; + + // Verify rb has been configured to report errors. + assert(rb->error_handler); + + // Use a local variable to store the information as we decode. At the end, + // if no errors have occurred, cm->seq_params is updated. + SequenceHeader sh = cm->seq_params; + SequenceHeader *const seq_params = &sh; + + seq_params->profile = av1_read_profile(rb); + if (seq_params->profile > CONFIG_MAX_DECODE_PROFILE) { + cm->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; + return 0; + } + + // 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 (!seq_params->still_picture && seq_params->reduced_still_picture_hdr) { + cm->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; + return 0; + } + + if (seq_params->reduced_still_picture_hdr) { + cm->timing_info_present = 0; + seq_params->decoder_model_info_present_flag = 0; + seq_params->display_model_info_present_flag = 0; + seq_params->operating_points_cnt_minus_1 = 0; + seq_params->operating_point_idc[0] = 0; + if (!read_bitstream_level(&seq_params->level[0], rb)) { + cm->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; + return 0; + } + seq_params->tier[0] = 0; + cm->op_params[0].decoder_model_param_present_flag = 0; + cm->op_params[0].display_model_param_present_flag = 0; + } else { + cm->timing_info_present = aom_rb_read_bit(rb); // timing_info_present_flag + if (cm->timing_info_present) { + av1_read_timing_info_header(cm, rb); + + seq_params->decoder_model_info_present_flag = aom_rb_read_bit(rb); + if (seq_params->decoder_model_info_present_flag) + av1_read_decoder_model_info(cm, rb); + } else { + seq_params->decoder_model_info_present_flag = 0; + } + seq_params->display_model_info_present_flag = aom_rb_read_bit(rb); + seq_params->operating_points_cnt_minus_1 = + aom_rb_read_literal(rb, OP_POINTS_CNT_MINUS_1_BITS); + for (int i = 0; i < seq_params->operating_points_cnt_minus_1 + 1; i++) { + seq_params->operating_point_idc[i] = + aom_rb_read_literal(rb, OP_POINTS_IDC_BITS); + if (!read_bitstream_level(&seq_params->level[i], rb)) { + cm->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; + return 0; + } + // This is the seq_level_idx[i] > 7 check in the spec. seq_level_idx 7 + // is equivalent to level 3.3. + if (seq_params->level[i].major > 3) + seq_params->tier[i] = aom_rb_read_bit(rb); + else + seq_params->tier[i] = 0; + if (seq_params->decoder_model_info_present_flag) { + cm->op_params[i].decoder_model_param_present_flag = aom_rb_read_bit(rb); + if (cm->op_params[i].decoder_model_param_present_flag) + av1_read_op_parameters_info(cm, rb, i); + } else { + cm->op_params[i].decoder_model_param_present_flag = 0; + } + if (cm->timing_info_present && + (cm->timing_info.equal_picture_interval || + cm->op_params[i].decoder_model_param_present_flag)) { + cm->op_params[i].bitrate = max_level_bitrate( + seq_params->profile, + major_minor_to_seq_level_idx(seq_params->level[i]), + seq_params->tier[i]); + // Level with seq_level_idx = 31 returns a high "dummy" bitrate to pass + // the check + if (cm->op_params[i].bitrate == 0) + aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM, + "AV1 does not support this combination of " + "profile, level, and tier."); + // Buffer size in bits/s is bitrate in bits/s * 1 s + cm->op_params[i].buffer_size = cm->op_params[i].bitrate; + } + if (cm->timing_info_present && cm->timing_info.equal_picture_interval && + !cm->op_params[i].decoder_model_param_present_flag) { + // When the decoder_model_parameters are not sent for this op, set + // the default ones that can be used with the resource availability mode + cm->op_params[i].decoder_buffer_delay = 70000; + cm->op_params[i].encoder_buffer_delay = 20000; + cm->op_params[i].low_delay_mode_flag = 0; + } + + if (seq_params->display_model_info_present_flag) { + cm->op_params[i].display_model_param_present_flag = aom_rb_read_bit(rb); + if (cm->op_params[i].display_model_param_present_flag) { + cm->op_params[i].initial_display_delay = + aom_rb_read_literal(rb, 4) + 1; + if (cm->op_params[i].initial_display_delay > 10) + aom_internal_error( + &cm->error, AOM_CODEC_UNSUP_BITSTREAM, + "AV1 does not support more than 10 decoded frames delay"); + } else { + cm->op_params[i].initial_display_delay = 10; + } + } else { + cm->op_params[i].display_model_param_present_flag = 0; + cm->op_params[i].initial_display_delay = 10; + } + } + } + // This decoder supports all levels. Choose operating point provided by + // external means + int operating_point = pbi->operating_point; + if (operating_point < 0 || + operating_point > seq_params->operating_points_cnt_minus_1) + operating_point = 0; + pbi->current_operating_point = + seq_params->operating_point_idc[operating_point]; + if (aom_get_num_layers_from_operating_point_idc( + pbi->current_operating_point, &cm->number_spatial_layers, + &cm->number_temporal_layers) != AOM_CODEC_OK) { + cm->error.error_code = AOM_CODEC_ERROR; + return 0; + } + + av1_read_sequence_header(cm, rb, seq_params); + + av1_read_color_config(rb, pbi->allow_lowbitdepth, seq_params, &cm->error); + if (!(seq_params->subsampling_x == 0 && seq_params->subsampling_y == 0) && + !(seq_params->subsampling_x == 1 && seq_params->subsampling_y == 1) && + !(seq_params->subsampling_x == 1 && seq_params->subsampling_y == 0)) { + aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM, + "Only 4:4:4, 4:2:2 and 4:2:0 are currently supported, " + "%d %d subsampling is not supported.\n", + seq_params->subsampling_x, seq_params->subsampling_y); + } + + seq_params->film_grain_params_present = aom_rb_read_bit(rb); + + if (av1_check_trailing_bits(pbi, rb) != 0) { + // cm->error.error_code is already set. + return 0; + } + + // If a sequence header has been decoded before, we check if the new + // one is consistent with the old one. + if (pbi->sequence_header_ready) { + if (!are_seq_headers_consistent(&cm->seq_params, seq_params)) + pbi->sequence_header_changed = 1; + } + + cm->seq_params = *seq_params; + pbi->sequence_header_ready = 1; + + return ((rb->bit_offset - saved_bit_offset + 7) >> 3); +} + +// On success, returns the frame header size. On failure, calls +// aom_internal_error and does not return. +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) { + return av1_decode_frame_headers_and_setup(pbi, rb, data, p_data_end, + trailing_bits_present); +} + +static int32_t read_tile_group_header(AV1Decoder *pbi, + struct aom_read_bit_buffer *rb, + int *start_tile, int *end_tile, + 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) { + *start_tile = 0; + *end_tile = 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"); + return -1; + } + *start_tile = + aom_rb_read_literal(rb, cm->log2_tile_rows + cm->log2_tile_cols); + *end_tile = 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 start_tile, end_tile; + int32_t header_size, tg_payload_size; + + assert((rb->bit_offset & 7) == 0); + assert(rb->bit_buffer + aom_rb_bytes_read(rb) == data); + + header_size = read_tile_group_header(pbi, rb, &start_tile, &end_tile, + tile_start_implicit); + if (header_size == -1 || byte_alignment(cm, rb)) return 0; + if (start_tile > end_tile) return header_size; + data += header_size; + av1_decode_tg_tiles_and_wrapup(pbi, data, data_end, p_data_end, start_tile, + end_tile, 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 = end_tile == cm->tile_rows * cm->tile_cols - 1; + return header_size + tg_payload_size; +} + +static void alloc_tile_list_buffer(AV1Decoder *pbi) { + // TODO(yunqing): for now, copy each tile's decoded YUV data directly to the + // output buffer. This needs to be modified according to the application + // requirement. + AV1_COMMON *const cm = &pbi->common; + const int tile_width_in_pixels = cm->tile_width * MI_SIZE; + const int tile_height_in_pixels = cm->tile_height * MI_SIZE; + const int ssy = cm->seq_params.subsampling_y; + const int ssx = cm->seq_params.subsampling_x; + const int num_planes = av1_num_planes(cm); + const size_t yplane_tile_size = tile_height_in_pixels * tile_width_in_pixels; + const size_t uvplane_tile_size = + (num_planes > 1) + ? (tile_height_in_pixels >> ssy) * (tile_width_in_pixels >> ssx) + : 0; + const size_t tile_size = (cm->seq_params.use_highbitdepth ? 2 : 1) * + (yplane_tile_size + 2 * uvplane_tile_size); + pbi->tile_list_size = tile_size * (pbi->tile_count_minus_1 + 1); + + if (pbi->tile_list_size > pbi->buffer_sz) { + if (pbi->tile_list_output != NULL) aom_free(pbi->tile_list_output); + pbi->tile_list_output = NULL; + + pbi->tile_list_output = (uint8_t *)aom_memalign(32, pbi->tile_list_size); + if (pbi->tile_list_output == NULL) + aom_internal_error(&cm->error, AOM_CODEC_MEM_ERROR, + "Failed to allocate the tile list output buffer"); + pbi->buffer_sz = pbi->tile_list_size; + } +} + +static void copy_decoded_tile_to_tile_list_buffer(AV1Decoder *pbi, + uint8_t **output) { + AV1_COMMON *const cm = &pbi->common; + const int tile_width_in_pixels = cm->tile_width * MI_SIZE; + const int tile_height_in_pixels = cm->tile_height * MI_SIZE; + const int ssy = cm->seq_params.subsampling_y; + const int ssx = cm->seq_params.subsampling_x; + const int num_planes = av1_num_planes(cm); + + // Copy decoded tile to the tile list output buffer. + YV12_BUFFER_CONFIG *cur_frame = get_frame_new_buffer(cm); + const int mi_row = pbi->dec_tile_row * cm->tile_height; + const int mi_col = pbi->dec_tile_col * cm->tile_width; + const int is_hbd = (cur_frame->flags & YV12_FLAG_HIGHBITDEPTH) ? 1 : 0; + uint8_t *bufs[MAX_MB_PLANE] = { NULL, NULL, NULL }; + int strides[MAX_MB_PLANE] = { 0, 0, 0 }; + int plane; + + for (plane = 0; plane < num_planes; ++plane) { + int shift_x = plane > 0 ? ssx : 0; + int shift_y = plane > 0 ? ssy : 0; + + bufs[plane] = cur_frame->buffers[plane]; + strides[plane] = + (plane > 0) ? cur_frame->strides[1] : cur_frame->strides[0]; + + bufs[plane] += mi_row * (MI_SIZE >> shift_y) * strides[plane] + + mi_col * (MI_SIZE >> shift_x); + + if (is_hbd) { + bufs[plane] = (uint8_t *)CONVERT_TO_SHORTPTR(bufs[plane]); + strides[plane] *= 2; + } + + int w, h; + w = (plane > 0 && shift_x > 0) ? ((tile_width_in_pixels + 1) >> shift_x) + : tile_width_in_pixels; + w *= (1 + is_hbd); + h = (plane > 0 && shift_y > 0) ? ((tile_height_in_pixels + 1) >> shift_y) + : tile_height_in_pixels; + int j; + + for (j = 0; j < h; ++j) { + memcpy(*output, bufs[plane], w); + bufs[plane] += strides[plane]; + *output += w; + } + } +} + +// Only called while large_scale_tile = 1. +static uint32_t read_and_decode_one_tile_list(AV1Decoder *pbi, + struct aom_read_bit_buffer *rb, + const uint8_t *data, + const uint8_t *data_end, + const uint8_t **p_data_end, + int *frame_decoding_finished) { + AV1_COMMON *const cm = &pbi->common; + uint32_t tile_list_payload_size = 0; + const int num_tiles = cm->tile_cols * cm->tile_rows; + const int start_tile = 0; + const int end_tile = num_tiles - 1; + int i = 0; + + // Process the tile list info. + pbi->output_frame_width_in_tiles_minus_1 = aom_rb_read_literal(rb, 8); + pbi->output_frame_height_in_tiles_minus_1 = aom_rb_read_literal(rb, 8); + pbi->tile_count_minus_1 = aom_rb_read_literal(rb, 16); + if (pbi->tile_count_minus_1 > MAX_TILES - 1) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return 0; + } + + // Allocate output frame buffer for the tile list. + alloc_tile_list_buffer(pbi); + + uint32_t tile_list_info_bytes = 4; + tile_list_payload_size += tile_list_info_bytes; + data += tile_list_info_bytes; + uint8_t *output = pbi->tile_list_output; + + for (i = 0; i <= pbi->tile_count_minus_1; i++) { + // Process 1 tile. + // Reset the bit reader. + rb->bit_offset = 0; + rb->bit_buffer = data; + + // Read out the tile info. + uint32_t tile_info_bytes = 5; + // Set reference for each tile. + int ref_idx = aom_rb_read_literal(rb, 8); + if (ref_idx >= MAX_EXTERNAL_REFERENCES) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return 0; + } + av1_set_reference_dec(cm, 0, 1, &pbi->ext_refs.refs[ref_idx]); + + pbi->dec_tile_row = aom_rb_read_literal(rb, 8); + pbi->dec_tile_col = aom_rb_read_literal(rb, 8); + if (pbi->dec_tile_row < 0 || pbi->dec_tile_col < 0 || + pbi->dec_tile_row >= cm->tile_rows || + pbi->dec_tile_col >= cm->tile_cols) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return 0; + } + + pbi->coded_tile_data_size = aom_rb_read_literal(rb, 16) + 1; + data += tile_info_bytes; + if ((size_t)(data_end - data) < pbi->coded_tile_data_size) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return 0; + } + + av1_decode_tg_tiles_and_wrapup(pbi, data, data + pbi->coded_tile_data_size, + p_data_end, start_tile, end_tile, 0); + uint32_t tile_payload_size = (uint32_t)(*p_data_end - data); + + tile_list_payload_size += tile_info_bytes + tile_payload_size; + + // Update data ptr for next tile decoding. + data = *p_data_end; + assert(data <= data_end); + + // Copy the decoded tile to the tile list output buffer. + copy_decoded_tile_to_tile_list_buffer(pbi, &output); + } + + *frame_decoding_finished = 1; + return tile_list_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_bit(rb); + int spatial_layer_description_present_flag = aom_rb_read_bit(rb); + int temporal_group_description_present_flag = aom_rb_read_bit(rb); + 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_bit(rb); + aom_rb_read_bit(rb); + 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; +} + +// On success, returns a boolean that indicates whether the decoding of the +// current frame is finished. On failure, sets cm->error.error_code and +// returns -1. +int 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; + uint32_t frame_header_size = 0; + ObuHeader obu_header; + memset(&obu_header, 0, sizeof(obu_header)); + pbi->seen_frame_header = 0; + + if (data_end < data) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + + // Reset pbi->camera_frame_header_ready to 0 if cm->large_scale_tile = 0. + if (!cm->large_scale_tile) pbi->camera_frame_header_ready = 0; + + // 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 && !pbi->seen_frame_header) { + *p_data_end = data; + cm->error.error_code = AOM_CODEC_OK; + break; + } + + 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 -1; + } + + // Record obu size header information. + pbi->obu_size_hdr.data = data + obu_header.size; + pbi->obu_size_hdr.size = bytes_read - obu_header.size; + + // 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; + + if ((size_t)(data_end - data) < payload_size) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + + 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; + continue; + } + } + + av1_init_read_bit_buffer(pbi, &rb, data, data + payload_size); + + switch (obu_header.type) { + case OBU_TEMPORAL_DELIMITER: + decoded_payload_size = read_temporal_delimiter_obu(); + pbi->seen_frame_header = 0; + break; + case OBU_SEQUENCE_HEADER: + decoded_payload_size = read_sequence_header_obu(pbi, &rb); + if (cm->error.error_code != AOM_CODEC_OK) return -1; + break; + case OBU_FRAME_HEADER: + case OBU_REDUNDANT_FRAME_HEADER: + case OBU_FRAME: + // Only decode first frame header received + if (!pbi->seen_frame_header || + (cm->large_scale_tile && !pbi->camera_frame_header_ready)) { + frame_header_size = read_frame_header_obu( + pbi, &rb, data, p_data_end, obu_header.type != OBU_FRAME); + pbi->seen_frame_header = 1; + if (!pbi->ext_tile_debug && cm->large_scale_tile) + pbi->camera_frame_header_ready = 1; + } else { + // TODO(wtc): Verify that the frame_header_obu is identical to the + // original frame_header_obu. For now just skip frame_header_size + // bytes in the bit buffer. + if (frame_header_size > payload_size) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + assert(rb.bit_offset == 0); + rb.bit_offset = 8 * frame_header_size; + } + + decoded_payload_size = frame_header_size; + pbi->frame_header_size = frame_header_size; + + if (cm->show_existing_frame) { + if (obu_header.type == OBU_FRAME) { + cm->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; + return -1; + } + frame_decoding_finished = 1; + pbi->seen_frame_header = 0; + break; + } + + // In large scale tile coding, decode the common camera frame header + // before any tile list OBU. + if (!pbi->ext_tile_debug && pbi->camera_frame_header_ready) { + frame_decoding_finished = 1; + // Skip the rest of the frame data. + decoded_payload_size = payload_size; + // Update data_end. + *p_data_end = data_end; + break; + } + + if (obu_header.type != OBU_FRAME) break; + obu_payload_offset = frame_header_size; + // Byte align the reader before reading the tile group. + if (byte_alignment(cm, &rb)) return -1; + AOM_FALLTHROUGH_INTENDED; // fall through to read tile group. + case OBU_TILE_GROUP: + if (!pbi->seen_frame_header) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + if (obu_payload_offset > payload_size) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + 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; + if (frame_decoding_finished) pbi->seen_frame_header = 0; + break; + case OBU_METADATA: + decoded_payload_size = read_metadata(data, payload_size); + break; + case OBU_TILE_LIST: + if (CONFIG_NORMAL_TILE_MODE) { + cm->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; + return -1; + } + + // This OBU type is purely for the large scale tile coding mode. + // The common camera frame header has to be already decoded. + if (!pbi->camera_frame_header_ready) { + cm->error.error_code = AOM_CODEC_CORRUPT_FRAME; + return -1; + } + + cm->large_scale_tile = 1; + av1_set_single_tile_decoding_mode(cm); + decoded_payload_size = + read_and_decode_one_tile_list(pbi, &rb, data, data + payload_size, + p_data_end, &frame_decoding_finished); + if (cm->error.error_code != AOM_CODEC_OK) return -1; + 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 -1; + } + + // 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 -1; + } + } + + data += payload_size; + } + + return frame_decoding_finished; +} |