| /* |
| * 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 "config/aom_scale_rtcd.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" |
| |
| 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, |
| const ObuHeader *obu_header) { |
| if (!pbi->current_operating_point || !obu_header->has_extension) { |
| 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(AV1_LEVEL *seq_level_idx, |
| struct aom_read_bit_buffer *rb) { |
| *seq_level_idx = aom_rb_read_literal(rb, LEVEL_BITS); |
| if (!is_valid_seq_level_idx(*seq_level_idx)) return 0; |
| return 1; |
| } |
| |
| // Returns whether two sequence headers are consistent with each other. |
| // Note that the 'op_params' field is not compared per Section 7.5 in the spec: |
| // Within a particular coded video sequence, the contents of |
| // sequence_header_obu must be bit-identical each time the sequence header |
| // appears except for the contents of operating_parameters_info. |
| static int are_seq_headers_consistent(const SequenceHeader *seq_params_old, |
| const SequenceHeader *seq_params_new) { |
| return !memcmp(seq_params_old, seq_params_new, |
| offsetof(SequenceHeader, op_params)); |
| } |
| |
| // 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) { |
| pbi->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) { |
| pbi->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; |
| return 0; |
| } |
| |
| if (seq_params->reduced_still_picture_hdr) { |
| seq_params->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->seq_level_idx[0], rb)) { |
| pbi->error.error_code = AOM_CODEC_UNSUP_BITSTREAM; |
| return 0; |
| } |
| seq_params->tier[0] = 0; |
| seq_params->op_params[0].decoder_model_param_present_flag = 0; |
| seq_params->op_params[0].display_model_param_present_flag = 0; |
| } else { |
| seq_params->timing_info_present = aom_rb_read_bit(rb); |
| if (seq_params->timing_info_present) { |
| av1_read_timing_info_header(&seq_params->timing_info, &pbi->error, 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(&seq_params->decoder_model_info, 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->seq_level_idx[i], rb)) { |
| pbi->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->seq_level_idx[i] >= SEQ_LEVEL_4_0) |
| seq_params->tier[i] = aom_rb_read_bit(rb); |
| else |
| seq_params->tier[i] = 0; |
| if (seq_params->decoder_model_info_present_flag) { |
| seq_params->op_params[i].decoder_model_param_present_flag = |
| aom_rb_read_bit(rb); |
| if (seq_params->op_params[i].decoder_model_param_present_flag) |
| av1_read_op_parameters_info(&seq_params->op_params[i], |
| seq_params->decoder_model_info |
| .encoder_decoder_buffer_delay_length, |
| rb); |
| } else { |
| seq_params->op_params[i].decoder_model_param_present_flag = 0; |
| } |
| if (seq_params->timing_info_present && |
| (seq_params->timing_info.equal_picture_interval || |
| seq_params->op_params[i].decoder_model_param_present_flag)) { |
| seq_params->op_params[i].bitrate = av1_max_level_bitrate( |
| seq_params->profile, seq_params->seq_level_idx[i], |
| seq_params->tier[i]); |
| // Level with seq_level_idx = 31 returns a high "dummy" bitrate to pass |
| // the check |
| if (seq_params->op_params[i].bitrate == 0) |
| aom_internal_error(&pbi->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 |
| seq_params->op_params[i].buffer_size = seq_params->op_params[i].bitrate; |
| } |
| if (seq_params->timing_info_present && |
| seq_params->timing_info.equal_picture_interval && |
| !seq_params->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 |
| seq_params->op_params[i].decoder_buffer_delay = 70000; |
| seq_params->op_params[i].encoder_buffer_delay = 20000; |
| seq_params->op_params[i].low_delay_mode_flag = 0; |
| } |
| |
| if (seq_params->display_model_info_present_flag) { |
| seq_params->op_params[i].display_model_param_present_flag = |
| aom_rb_read_bit(rb); |
| if (seq_params->op_params[i].display_model_param_present_flag) { |
| seq_params->op_params[i].initial_display_delay = |
| aom_rb_read_literal(rb, 4) + 1; |
| if (seq_params->op_params[i].initial_display_delay > 10) |
| aom_internal_error( |
| &pbi->error, AOM_CODEC_UNSUP_BITSTREAM, |
| "AV1 does not support more than 10 decoded frames delay"); |
| } else { |
| seq_params->op_params[i].initial_display_delay = 10; |
| } |
| } else { |
| seq_params->op_params[i].display_model_param_present_flag = 0; |
| seq_params->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, &pbi->number_spatial_layers, |
| &pbi->number_temporal_layers) != AOM_CODEC_OK) { |
| pbi->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, &pbi->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(&pbi->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) { |
| // pbi->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. If show existing frame, |
| // also marks the data processing to end after the frame header. |
| 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) { |
| const uint32_t hdr_size = |
| av1_decode_frame_headers_and_setup(pbi, rb, trailing_bits_present); |
| const AV1_COMMON *cm = &pbi->common; |
| if (cm->show_existing_frame) { |
| *p_data_end = data + hdr_size; |
| } |
| return hdr_size; |
| } |
| |
| // On success, returns the tile group header size. On failure, calls |
| // aom_internal_error() and returns -1. |
| 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; |
| CommonTileParams *const tiles = &cm->tiles; |
| uint32_t saved_bit_offset = rb->bit_offset; |
| int tile_start_and_end_present_flag = 0; |
| const int num_tiles = tiles->rows * tiles->cols; |
| |
| if (!tiles->large_scale && num_tiles > 1) { |
| tile_start_and_end_present_flag = aom_rb_read_bit(rb); |
| if (tile_start_implicit && tile_start_and_end_present_flag) { |
| aom_internal_error( |
| &pbi->error, AOM_CODEC_UNSUP_BITSTREAM, |
| "For OBU_FRAME type obu tile_start_and_end_present_flag must be 0"); |
| return -1; |
| } |
| } |
| if (tiles->large_scale || num_tiles == 1 || |
| !tile_start_and_end_present_flag) { |
| *start_tile = 0; |
| *end_tile = num_tiles - 1; |
| } else { |
| int tile_bits = tiles->log2_rows + tiles->log2_cols; |
| *start_tile = aom_rb_read_literal(rb, tile_bits); |
| *end_tile = aom_rb_read_literal(rb, tile_bits); |
| } |
| if (*start_tile != pbi->next_start_tile) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "tg_start (%d) must be equal to %d", *start_tile, |
| pbi->next_start_tile); |
| return -1; |
| } |
| if (*start_tile > *end_tile) { |
| aom_internal_error( |
| &pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "tg_end (%d) must be greater than or equal to tg_start (%d)", *end_tile, |
| *start_tile); |
| return -1; |
| } |
| if (*end_tile >= num_tiles) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "tg_end (%d) must be less than NumTiles (%d)", *end_tile, |
| num_tiles); |
| return -1; |
| } |
| pbi->next_start_tile = (*end_tile == num_tiles - 1) ? 0 : *end_tile + 1; |
| |
| return ((rb->bit_offset - saved_bit_offset + 7) >> 3); |
| } |
| |
| // On success, returns the tile group OBU size. On failure, sets |
| // pbi->common.error.error_code and returns 0. |
| 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; |
| 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); |
| |
| *is_last_tg = end_tile == cm->tiles.rows * cm->tiles.cols - 1; |
| return header_size + tg_payload_size; |
| } |
| |
| static void alloc_tile_list_buffer(AV1Decoder *pbi) { |
| // The resolution of the output frame is read out from the bitstream. The data |
| // are stored in the order of Y plane, U plane and V plane. As an example, for |
| // image format 4:2:0, the output frame of U plane and V plane is 1/4 of the |
| // output frame. |
| AV1_COMMON *const cm = &pbi->common; |
| int tile_width, tile_height; |
| av1_get_uniform_tile_size(cm, &tile_width, &tile_height); |
| const int tile_width_in_pixels = tile_width * MI_SIZE; |
| const int tile_height_in_pixels = tile_height * MI_SIZE; |
| const int output_frame_width = |
| (pbi->output_frame_width_in_tiles_minus_1 + 1) * tile_width_in_pixels; |
| const int output_frame_height = |
| (pbi->output_frame_height_in_tiles_minus_1 + 1) * tile_height_in_pixels; |
| // The output frame is used to store the decoded tile list. The decoded tile |
| // list has to fit into 1 output frame. |
| assert((pbi->tile_count_minus_1 + 1) <= |
| (pbi->output_frame_width_in_tiles_minus_1 + 1) * |
| (pbi->output_frame_height_in_tiles_minus_1 + 1)); |
| |
| // Allocate the tile list output buffer. |
| // Note: if cm->seq_params->use_highbitdepth is 1 and |
| // cm->seq_params->bit_depth is 8, we could allocate less memory, namely, 8 |
| // bits/pixel. |
| if (aom_alloc_frame_buffer(&pbi->tile_list_outbuf, output_frame_width, |
| output_frame_height, cm->seq_params->subsampling_x, |
| cm->seq_params->subsampling_y, |
| (cm->seq_params->use_highbitdepth && |
| (cm->seq_params->bit_depth > AOM_BITS_8)), |
| 0, cm->features.byte_alignment)) |
| aom_internal_error(&pbi->error, AOM_CODEC_MEM_ERROR, |
| "Failed to allocate the tile list output buffer"); |
| } |
| |
| static void yv12_tile_copy(const YV12_BUFFER_CONFIG *src, int hstart1, |
| int hend1, int vstart1, int vend1, |
| YV12_BUFFER_CONFIG *dst, int hstart2, int vstart2, |
| int plane) { |
| const int src_stride = (plane > 0) ? src->strides[1] : src->strides[0]; |
| const int dst_stride = (plane > 0) ? dst->strides[1] : dst->strides[0]; |
| int row, col; |
| |
| assert(src->flags & YV12_FLAG_HIGHBITDEPTH); |
| assert(!(dst->flags & YV12_FLAG_HIGHBITDEPTH)); |
| |
| const uint16_t *src16 = |
| CONVERT_TO_SHORTPTR(src->buffers[plane] + vstart1 * src_stride + hstart1); |
| uint8_t *dst8 = dst->buffers[plane] + vstart2 * dst_stride + hstart2; |
| |
| for (row = vstart1; row < vend1; ++row) { |
| for (col = 0; col < (hend1 - hstart1); ++col) *dst8++ = (uint8_t)(*src16++); |
| src16 += src_stride - (hend1 - hstart1); |
| dst8 += dst_stride - (hend1 - hstart1); |
| } |
| return; |
| } |
| |
| static void copy_decoded_tile_to_tile_list_buffer(AV1Decoder *pbi, |
| int tile_idx) { |
| AV1_COMMON *const cm = &pbi->common; |
| int tile_width, tile_height; |
| av1_get_uniform_tile_size(cm, &tile_width, &tile_height); |
| const int tile_width_in_pixels = tile_width * MI_SIZE; |
| const int tile_height_in_pixels = 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); |
| |
| YV12_BUFFER_CONFIG *cur_frame = &cm->cur_frame->buf; |
| const int tr = tile_idx / (pbi->output_frame_width_in_tiles_minus_1 + 1); |
| const int tc = tile_idx % (pbi->output_frame_width_in_tiles_minus_1 + 1); |
| int plane; |
| |
| // Copy decoded tile to the tile list output buffer. |
| for (plane = 0; plane < num_planes; ++plane) { |
| const int shift_x = plane > 0 ? ssx : 0; |
| const int shift_y = plane > 0 ? ssy : 0; |
| const int h = tile_height_in_pixels >> shift_y; |
| const int w = tile_width_in_pixels >> shift_x; |
| |
| // src offset |
| int vstart1 = pbi->dec_tile_row * h; |
| int vend1 = vstart1 + h; |
| int hstart1 = pbi->dec_tile_col * w; |
| int hend1 = hstart1 + w; |
| // dst offset |
| int vstart2 = tr * h; |
| int hstart2 = tc * w; |
| |
| if (cm->seq_params->use_highbitdepth && |
| cm->seq_params->bit_depth == AOM_BITS_8) { |
| yv12_tile_copy(cur_frame, hstart1, hend1, vstart1, vend1, |
| &pbi->tile_list_outbuf, hstart2, vstart2, plane); |
| } else { |
| switch (plane) { |
| case 0: |
| aom_yv12_partial_copy_y(cur_frame, hstart1, hend1, vstart1, vend1, |
| &pbi->tile_list_outbuf, hstart2, vstart2); |
| break; |
| case 1: |
| aom_yv12_partial_copy_u(cur_frame, hstart1, hend1, vstart1, vend1, |
| &pbi->tile_list_outbuf, hstart2, vstart2); |
| break; |
| case 2: |
| aom_yv12_partial_copy_v(cur_frame, hstart1, hend1, vstart1, vend1, |
| &pbi->tile_list_outbuf, hstart2, vstart2); |
| break; |
| default: assert(0); |
| } |
| } |
| } |
| } |
| |
| // Only called while large_scale_tile = 1. |
| // |
| // On success, returns the tile list OBU size. On failure, sets |
| // pbi->common.error.error_code and returns 0. |
| 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->tiles.cols * cm->tiles.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) { |
| pbi->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; |
| |
| int tile_idx = 0; |
| 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) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return 0; |
| } |
| av1_set_reference_dec(cm, cm->remapped_ref_idx[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->tiles.rows || |
| pbi->dec_tile_col >= cm->tiles.cols) { |
| pbi->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) { |
| pbi->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, tile_idx); |
| tile_idx++; |
| } |
| |
| *frame_decoding_finished = 1; |
| return tile_list_payload_size; |
| } |
| |
| // Returns the last nonzero byte index in 'data'. If there is no nonzero byte in |
| // 'data', returns -1. |
| static int get_last_nonzero_byte_index(const uint8_t *data, size_t sz) { |
| // Scan backward and return on the first nonzero byte. |
| int i = (int)sz - 1; |
| while (i >= 0 && data[i] == 0) { |
| --i; |
| } |
| return i; |
| } |
| |
| // Allocates metadata that was read and adds it to the decoders metadata array. |
| static void alloc_read_metadata(AV1Decoder *const pbi, |
| OBU_METADATA_TYPE metadata_type, |
| const uint8_t *data, size_t sz, |
| aom_metadata_insert_flags_t insert_flag) { |
| if (!pbi->metadata) { |
| pbi->metadata = aom_img_metadata_array_alloc(0); |
| if (!pbi->metadata) { |
| aom_internal_error(&pbi->error, AOM_CODEC_MEM_ERROR, |
| "Failed to allocate metadata array"); |
| } |
| } |
| aom_metadata_t *metadata = |
| aom_img_metadata_alloc(metadata_type, data, sz, insert_flag); |
| if (!metadata) { |
| aom_internal_error(&pbi->error, AOM_CODEC_MEM_ERROR, |
| "Error allocating metadata"); |
| } |
| aom_metadata_t **metadata_array = |
| (aom_metadata_t **)realloc(pbi->metadata->metadata_array, |
| (pbi->metadata->sz + 1) * sizeof(metadata)); |
| if (!metadata_array) { |
| aom_img_metadata_free(metadata); |
| aom_internal_error(&pbi->error, AOM_CODEC_MEM_ERROR, |
| "Error growing metadata array"); |
| } |
| pbi->metadata->metadata_array = metadata_array; |
| pbi->metadata->metadata_array[pbi->metadata->sz] = metadata; |
| pbi->metadata->sz++; |
| } |
| |
| // On failure, calls aom_internal_error() and does not return. |
| static void read_metadata_itut_t35(AV1Decoder *const pbi, const uint8_t *data, |
| size_t sz) { |
| if (sz == 0) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "itu_t_t35_country_code is missing"); |
| } |
| int country_code_size = 1; |
| if (*data == 0xFF) { |
| if (sz == 1) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "itu_t_t35_country_code_extension_byte is missing"); |
| } |
| ++country_code_size; |
| } |
| int end_index = get_last_nonzero_byte_index(data, sz); |
| if (end_index < country_code_size) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "No trailing bits found in ITU-T T.35 metadata OBU"); |
| } |
| // itu_t_t35_payload_bytes is byte aligned. Section 6.7.2 of the spec says: |
| // itu_t_t35_payload_bytes shall be bytes containing data registered as |
| // specified in Recommendation ITU-T T.35. |
| // Therefore the first trailing byte should be 0x80. |
| if (data[end_index] != 0x80) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "The last nonzero byte of the ITU-T T.35 metadata OBU " |
| "is 0x%02x, should be 0x80.", |
| data[end_index]); |
| } |
| alloc_read_metadata(pbi, OBU_METADATA_TYPE_ITUT_T35, data, end_index, |
| AOM_MIF_ANY_FRAME); |
| } |
| |
| // On success, returns the number of bytes read from 'data'. On failure, calls |
| // aom_internal_error() and does not return. |
| static size_t read_metadata_hdr_cll(AV1Decoder *const pbi, const uint8_t *data, |
| size_t sz) { |
| const size_t kHdrCllPayloadSize = 4; |
| if (sz < kHdrCllPayloadSize) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "Incorrect HDR CLL metadata payload size"); |
| } |
| alloc_read_metadata(pbi, OBU_METADATA_TYPE_HDR_CLL, data, kHdrCllPayloadSize, |
| AOM_MIF_ANY_FRAME); |
| return kHdrCllPayloadSize; |
| } |
| |
| // On success, returns the number of bytes read from 'data'. On failure, calls |
| // aom_internal_error() and does not return. |
| static size_t read_metadata_hdr_mdcv(AV1Decoder *const pbi, const uint8_t *data, |
| size_t sz) { |
| const size_t kMdcvPayloadSize = 24; |
| if (sz < kMdcvPayloadSize) { |
| aom_internal_error(&pbi->error, AOM_CODEC_CORRUPT_FRAME, |
| "Incorrect HDR MDCV metadata payload size"); |
| } |
| alloc_read_metadata(pbi, OBU_METADATA_TYPE_HDR_MDCV, data, kMdcvPayloadSize, |
| AOM_MIF_ANY_FRAME); |
| return kMdcvPayloadSize; |
| } |
| |
| static void scalability_structure(struct aom_read_bit_buffer *rb) { |
| const int spatial_layers_cnt_minus_1 = aom_rb_read_literal(rb, 2); |
| const int spatial_layer_dimensions_present_flag = aom_rb_read_bit(rb); |
| const int spatial_layer_description_present_flag = aom_rb_read_bit(rb); |
| const int temporal_group_description_present_flag = aom_rb_read_bit(rb); |
| // scalability_structure_reserved_3bits must be set to zero and be ignored by |
| // decoders. |
| aom_rb_read_literal(rb, 3); |
| |
| if (spatial_layer_dimensions_present_flag) { |
| for (int i = 0; i <= spatial_layers_cnt_minus_1; i++) { |
| aom_rb_read_literal(rb, 16); |
| aom_rb_read_literal(rb, 16); |
| } |
| } |
| if (spatial_layer_description_present_flag) { |
| for (int i = 0; i <= spatial_layers_cnt_minus_1; i++) { |
| aom_rb_read_literal(rb, 8); |
| } |
| } |
| if (temporal_group_description_present_flag) { |
| const int temporal_group_size = aom_rb_read_literal(rb, 8); |
| for (int i = 0; i < temporal_group_size; i++) { |
| aom_rb_read_literal(rb, 3); |
| aom_rb_read_bit(rb); |
| aom_rb_read_bit(rb); |
| const int temporal_group_ref_cnt = aom_rb_read_literal(rb, 3); |
| for (int j = 0; j < temporal_group_ref_cnt; j++) { |
| aom_rb_read_literal(rb, 8); |
| } |
| } |
| } |
| } |
| |
| static void read_metadata_scalability(struct aom_read_bit_buffer *rb) { |
| const int scalability_mode_idc = aom_rb_read_literal(rb, 8); |
| if (scalability_mode_idc == SCALABILITY_SS) { |
| scalability_structure(rb); |
| } |
| } |
| |
| static void read_metadata_timecode(struct aom_read_bit_buffer *rb) { |
| aom_rb_read_literal(rb, 5); // counting_type f(5) |
| const 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 { |
| const 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) |
| const 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) |
| const 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) |
| const int time_offset_length = aom_rb_read_literal(rb, 5); |
| if (time_offset_length) { |
| // time_offset_value f(time_offset_length) |
| aom_rb_read_literal(rb, time_offset_length); |
| } |
| } |
| |
| // Returns the last nonzero byte in 'data'. If there is no nonzero byte in |
| // 'data', returns 0. |
| // |
| // Call this function to check the following requirement in the spec: |
| // This implies that when any payload data is present for this OBU type, at |
| // least one byte of the payload data (including the trailing bit) shall not |
| // be equal to 0. |
| static uint8_t get_last_nonzero_byte(const uint8_t *data, size_t sz) { |
| // Scan backward and return on the first nonzero byte. |
| size_t i = sz; |
| while (i != 0) { |
| --i; |
| if (data[i] != 0) return data[i]; |
| } |
| return 0; |
| } |
| |
| // Checks the metadata for correct syntax but ignores the parsed metadata. |
| // |
| // On success, returns the number of bytes read from 'data'. On failure, sets |
| // pbi->common.error.error_code and returns 0, or calls aom_internal_error() |
| // and does not return. |
| static size_t read_metadata(AV1Decoder *pbi, const uint8_t *data, size_t sz) { |
| size_t type_length; |
| uint64_t type_value; |
| if (aom_uleb_decode(data, sz, &type_value, &type_length) < 0) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return 0; |
| } |
| const OBU_METADATA_TYPE metadata_type = (OBU_METADATA_TYPE)type_value; |
| if (metadata_type == 0 || metadata_type >= 6) { |
| // If metadata_type is reserved for future use or a user private value, |
| // ignore the entire OBU and just check trailing bits. |
| if (get_last_nonzero_byte(data + type_length, sz - type_length) == 0) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return 0; |
| } |
| return sz; |
| } |
| if (metadata_type == OBU_METADATA_TYPE_ITUT_T35) { |
| // read_metadata_itut_t35() checks trailing bits. |
| read_metadata_itut_t35(pbi, data + type_length, sz - type_length); |
| return sz; |
| } else if (metadata_type == OBU_METADATA_TYPE_HDR_CLL) { |
| size_t bytes_read = |
| type_length + |
| read_metadata_hdr_cll(pbi, data + type_length, sz - type_length); |
| if (get_last_nonzero_byte(data + bytes_read, sz - bytes_read) != 0x80) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return 0; |
| } |
| return sz; |
| } else if (metadata_type == OBU_METADATA_TYPE_HDR_MDCV) { |
| size_t bytes_read = |
| type_length + |
| read_metadata_hdr_mdcv(pbi, data + type_length, sz - type_length); |
| if (get_last_nonzero_byte(data + bytes_read, sz - bytes_read) != 0x80) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return 0; |
| } |
| return sz; |
| } |
| |
| struct aom_read_bit_buffer rb; |
| av1_init_read_bit_buffer(pbi, &rb, data + type_length, data + sz); |
| if (metadata_type == OBU_METADATA_TYPE_SCALABILITY) { |
| read_metadata_scalability(&rb); |
| } else { |
| assert(metadata_type == OBU_METADATA_TYPE_TIMECODE); |
| read_metadata_timecode(&rb); |
| } |
| if (av1_check_trailing_bits(pbi, &rb) != 0) { |
| // pbi->error.error_code is already set. |
| return 0; |
| } |
| assert((rb.bit_offset & 7) == 0); |
| return type_length + (rb.bit_offset >> 3); |
| } |
| |
| // On success, returns 'sz'. On failure, sets pbi->common.error.error_code and |
| // returns 0. |
| static size_t read_padding(AV1_COMMON *const cm, const uint8_t *data, |
| size_t sz) { |
| // The spec allows a padding OBU to be header-only (i.e., obu_size = 0). So |
| // check trailing bits only if sz > 0. |
| if (sz > 0) { |
| // The payload of a padding OBU is byte aligned. Therefore the first |
| // trailing byte should be 0x80. See https://crbug.com/aomedia/2393. |
| const uint8_t last_nonzero_byte = get_last_nonzero_byte(data, sz); |
| if (last_nonzero_byte != 0x80) { |
| cm->error->error_code = AOM_CODEC_CORRUPT_FRAME; |
| return 0; |
| } |
| } |
| return sz; |
| } |
| |
| // On success, returns a boolean that indicates whether the decoding of the |
| // current frame is finished. On failure, sets pbi->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; |
| // Whenever pbi->seen_frame_header is set to 1, frame_header is set to the |
| // beginning of the frame_header_obu and frame_header_size is set to its |
| // size. This allows us to check if a redundant frame_header_obu is a copy |
| // of the previous frame_header_obu. |
| // |
| // Initialize frame_header to a dummy nonnull pointer, otherwise the Clang |
| // Static Analyzer in clang 7.0.1 will falsely warn that a null pointer is |
| // passed as an argument to a 'nonnull' parameter of memcmp(). The initial |
| // value will not be used. |
| const uint8_t *frame_header = data; |
| uint32_t frame_header_size = 0; |
| ObuHeader obu_header; |
| memset(&obu_header, 0, sizeof(obu_header)); |
| pbi->seen_frame_header = 0; |
| pbi->next_start_tile = 0; |
| pbi->num_tile_groups = 0; |
| |
| if (data_end < data) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| |
| // Reset pbi->camera_frame_header_ready to 0 if cm->tiles.large_scale = 0. |
| if (!cm->tiles.large_scale) pbi->camera_frame_header_ready = 0; |
| |
| // decode frame as a series of OBUs |
| while (!frame_decoding_finished && pbi->error.error_code == AOM_CODEC_OK) { |
| 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; |
| pbi->error.error_code = AOM_CODEC_OK; |
| break; |
| } |
| |
| aom_codec_err_t status = |
| aom_read_obu_header_and_size(data, bytes_available, pbi->is_annexb, |
| &obu_header, &payload_size, &bytes_read); |
| |
| if (status != AOM_CODEC_OK) { |
| pbi->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) { |
| pbi->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) { |
| // 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(); |
| if (pbi->seen_frame_header) { |
| // A new temporal unit has started, but the frame in the previous |
| // temporal unit is incomplete. |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| break; |
| case OBU_SEQUENCE_HEADER: |
| decoded_payload_size = read_sequence_header_obu(pbi, &rb); |
| if (pbi->error.error_code != AOM_CODEC_OK) return -1; |
| // The sequence header should not change in the middle of a frame. |
| if (pbi->sequence_header_changed && pbi->seen_frame_header) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| break; |
| case OBU_FRAME_HEADER: |
| case OBU_REDUNDANT_FRAME_HEADER: |
| case OBU_FRAME: |
| if (obu_header.type == OBU_REDUNDANT_FRAME_HEADER) { |
| if (!pbi->seen_frame_header) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| } else { |
| // OBU_FRAME_HEADER or OBU_FRAME. |
| if (pbi->seen_frame_header) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| } |
| // Only decode first frame header received |
| if (!pbi->seen_frame_header || |
| (cm->tiles.large_scale && !pbi->camera_frame_header_ready)) { |
| frame_header_size = read_frame_header_obu( |
| pbi, &rb, data, p_data_end, obu_header.type != OBU_FRAME); |
| frame_header = data; |
| pbi->seen_frame_header = 1; |
| if (!pbi->ext_tile_debug && cm->tiles.large_scale) |
| pbi->camera_frame_header_ready = 1; |
| } else { |
| // Verify that the frame_header_obu is identical to the original |
| // frame_header_obu. |
| if (frame_header_size > payload_size || |
| memcmp(data, frame_header, frame_header_size) != 0) { |
| pbi->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; |
| cm->cur_frame->temporal_id = obu_header.temporal_layer_id; |
| cm->cur_frame->spatial_id = obu_header.spatial_layer_id; |
| |
| if (cm->show_existing_frame) { |
| if (obu_header.type == OBU_FRAME) { |
| pbi->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. |
| // byte_alignment() has set pbi->error.error_code if it returns -1. |
| 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) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| if (obu_payload_offset > payload_size) { |
| pbi->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); |
| if (pbi->error.error_code != AOM_CODEC_OK) return -1; |
| is_first_tg_obu_received = 0; |
| if (frame_decoding_finished) { |
| pbi->seen_frame_header = 0; |
| pbi->next_start_tile = 0; |
| } |
| pbi->num_tile_groups++; |
| break; |
| case OBU_METADATA: |
| decoded_payload_size = read_metadata(pbi, data, payload_size); |
| if (pbi->error.error_code != AOM_CODEC_OK) return -1; |
| break; |
| case OBU_TILE_LIST: |
| if (CONFIG_NORMAL_TILE_MODE) { |
| pbi->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) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| |
| cm->tiles.large_scale = 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 (pbi->error.error_code != AOM_CODEC_OK) return -1; |
| break; |
| case OBU_PADDING: |
| decoded_payload_size = read_padding(cm, data, payload_size); |
| if (pbi->error.error_code != AOM_CODEC_OK) return -1; |
| break; |
| default: |
| // Skip unrecognized OBUs |
| if (payload_size > 0 && |
| get_last_nonzero_byte(data, payload_size) == 0) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| 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) { |
| pbi->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) { |
| pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME; |
| return -1; |
| } |
| } |
| |
| data += payload_size; |
| } |
| |
| if (pbi->error.error_code != AOM_CODEC_OK) return -1; |
| return frame_decoding_finished; |
| } |