av2/decoder/obu_ci.c - avm - Git at Google

 /*
  * Copyright (c) 2025, Alliance for Open Media. All rights reserved
  *
  * This source code is subject to the terms of the BSD 3-Clause Clear License
  * and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
  * License was not distributed with this source code in the LICENSE file, you
  * can obtain it at aomedia.org/license/software-license/bsd-3-c-c/.  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
  * aomedia.org/license/patent-license/.
  */

 #include <assert.h>

 #include "config/avm_config.h"
 #include "config/avm_scale_rtcd.h"
 #include "avm/avm_codec.h"
 #include "avm_dsp/bitreader_buffer.h"
 #include "avm_ports/mem_ops.h"
 #include "av2/common/common.h"
 #include "av2/common/obu_util.h"
 #include "av2/common/timing.h"
 #include "av2/decoder/decoder.h"
 #include "av2/decoder/decodeframe.h"
 #include "av2/decoder/obu.h"
 #include "av2/common/av2_common_int.h"

 static void av2_set_color_info(ContentInterpretation *ci_params) {
   assert(ci_params->color_info.color_description_idc !=
          AVM_COLOR_DESC_IDC_EXPLICIT);
   switch (ci_params->color_info.color_description_idc) {
     case AVM_COLOR_DESC_IDC_BT709SDR:
       ci_params->color_info.color_primaries = AVM_CICP_CP_BT_709;
       ci_params->color_info.transfer_characteristics = AVM_CICP_TC_BT_709;
       ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_470_B_G;
       break;
     case AVM_COLOR_DESC_IDC_BT2100PQ:
       ci_params->color_info.color_primaries = AVM_CICP_CP_BT_2020;
       ci_params->color_info.transfer_characteristics = AVM_CICP_TC_SMPTE_2084;
       ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_2020_NCL;
       break;
     case AVM_COLOR_DESC_IDC_BT2100HLG:
       ci_params->color_info.color_primaries = AVM_CICP_CP_BT_2020;
       ci_params->color_info.transfer_characteristics =
           AVM_CICP_TC_BT_2020_10_BIT;
       ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_2020_NCL;
       break;
     case AVM_COLOR_DESC_IDC_SRGB:
       ci_params->color_info.color_primaries = AVM_CICP_CP_BT_709;
       ci_params->color_info.transfer_characteristics = AVM_CICP_TC_SRGB;
       ci_params->color_info.matrix_coefficients = AVM_CICP_MC_IDENTITY;
       break;
     case AVM_COLOR_DESC_IDC_SRGBSYCC:
       ci_params->color_info.color_primaries = AVM_CICP_CP_BT_709;
       ci_params->color_info.transfer_characteristics = AVM_CICP_TC_SRGB;
       ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_470_B_G;
       break;
     default:
       ci_params->color_info.color_primaries = AVM_CICP_CP_UNSPECIFIED;
       ci_params->color_info.transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
       ci_params->color_info.matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
       break;
   }
 }

 static int av2_set_sar_info(ContentInterpretation *ci_params) {
   int supported_sample_aspect_ratio = 1;
   switch (ci_params->sar_info.sar_aspect_ratio_idc) {
     case AVM_SAR_IDC_UNSPECIFIED:
     case AVM_SAR_IDC_255: break;
     case AVM_SAR_IDC_1_TO_1:
       ci_params->sar_info.sar_width = 1;
       ci_params->sar_info.sar_height = 1;
       break;
     case AVM_SAR_IDC_12_TO_11:
       ci_params->sar_info.sar_width = 12;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_10_TO_11:
       ci_params->sar_info.sar_width = 10;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_16_TO_11:
       ci_params->sar_info.sar_width = 16;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_40_TO_33:
       ci_params->sar_info.sar_width = 40;
       ci_params->sar_info.sar_height = 33;
       break;
     case AVM_SAR_IDC_24_TO_11:
       ci_params->sar_info.sar_width = 24;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_20_TO_11:
       ci_params->sar_info.sar_width = 20;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_32_TO_11:
       ci_params->sar_info.sar_width = 32;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_80_TO_33:
       ci_params->sar_info.sar_width = 80;
       ci_params->sar_info.sar_height = 33;
       break;
     case AVM_SAR_IDC_18_TO_11:
       ci_params->sar_info.sar_width = 18;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_15_TO_11:
       ci_params->sar_info.sar_width = 15;
       ci_params->sar_info.sar_height = 11;
       break;
     case AVM_SAR_IDC_64_TO_33:
       ci_params->sar_info.sar_width = 64;
       ci_params->sar_info.sar_height = 33;
       break;
     case AVM_SAR_IDC_160_TO_99:
       ci_params->sar_info.sar_width = 160;
       ci_params->sar_info.sar_height = 99;
       break;
     case AVM_SAR_IDC_4_TO_3:
       ci_params->sar_info.sar_width = 4;
       ci_params->sar_info.sar_height = 3;
       break;
     case AVM_SAR_IDC_3_TO_2:
       ci_params->sar_info.sar_width = 3;
       ci_params->sar_info.sar_height = 2;
       break;
     case AVM_SAR_IDC_2_TO_1:
       ci_params->sar_info.sar_width = 2;
       ci_params->sar_info.sar_height = 1;
       break;
     default: supported_sample_aspect_ratio = 0; break;
   }
   return supported_sample_aspect_ratio;
 }

 static INLINE void av2_read_color_info(struct ContentInterpretation *ci_params,
                                        struct avm_read_bit_buffer *rb) {
   ColorInfo *col_info = &ci_params->color_info;
   col_info->color_description_idc = avm_rb_read_rice_golomb(rb, 2);

   if (col_info->color_description_idc == AVM_COLOR_DESC_IDC_EXPLICIT) {
     col_info->color_primaries = avm_rb_read_literal(rb, 8);
     col_info->transfer_characteristics = avm_rb_read_literal(rb, 8);
     col_info->matrix_coefficients = avm_rb_read_literal(rb, 8);
   } else {
     col_info->color_primaries = AVM_CICP_CP_UNSPECIFIED;
     col_info->transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
     col_info->matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
   }
   col_info->full_range_flag = avm_rb_read_bit(rb);
 }

 static INLINE void av2_read_sample_aspect_ratio_information(
     struct ContentInterpretation *ci_params, struct avm_read_bit_buffer *rb) {
   SarInfo *sar_info = &ci_params->sar_info;
   sar_info->sar_aspect_ratio_idc = avm_rb_read_literal(rb, 8);
   if (sar_info->sar_aspect_ratio_idc == AVM_SAR_IDC_255) {
     sar_info->sar_width = avm_rb_read_uvlc(rb);
     sar_info->sar_height = avm_rb_read_uvlc(rb);
   }
 }

 void av2_init_ci_params(ContentInterpretation *ci_params) {
   memset(ci_params, 0, sizeof(ContentInterpretation));
   ci_params->ci_chroma_sample_position[0] = AVM_CSP_UNSPECIFIED;
   ci_params->ci_chroma_sample_position[1] = AVM_CSP_UNSPECIFIED;
   ci_params->color_info.color_primaries = AVM_CICP_CP_UNSPECIFIED;
   ci_params->color_info.transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
   ci_params->color_info.matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
 }

 static int av2_ci_params_identical(const ContentInterpretation *ci1,
                                    const ContentInterpretation *ci2) {
   if (!memcmp(ci1, ci2, sizeof(ContentInterpretation))) return 1;
   return 0;
 }

 uint32_t av2_read_content_interpretation_obu(struct AV2Decoder *pbi,
                                              struct avm_read_bit_buffer *rb) {
   AV2_COMMON *const cm = &pbi->common;
   const int obu_mlayer_id = cm->mlayer_id;
   const uint32_t saved_bit_offset = rb->bit_offset;
   cm->error.error_code = AVM_CODEC_OK;
   assert(rb->error_handler);

   // Parse CI OBU into a temp structure
   ContentInterpretation ci_temp;
   av2_init_ci_params(&ci_temp);
   ci_temp.ci_scan_type_idc = avm_rb_read_literal(rb, 2);
   ci_temp.ci_color_description_present_flag = avm_rb_read_bit(rb);
   ci_temp.ci_chroma_sample_position_present_flag = avm_rb_read_bit(rb);
   ci_temp.ci_aspect_ratio_info_present_flag = avm_rb_read_bit(rb);
   ci_temp.ci_timing_info_present_flag = avm_rb_read_bit(rb);
   ci_temp.ci_extension_present_flag = avm_rb_read_bit(rb);
   (void)avm_rb_read_bit(rb);  // ci_reserved_1bit

   if (ci_temp.ci_color_description_present_flag) {
     av2_read_color_info(&ci_temp, rb);
     if (ci_temp.color_info.color_description_idc != AVM_COLOR_DESC_IDC_EXPLICIT)
       av2_set_color_info(&ci_temp);
   } else {
     ci_temp.color_info.color_primaries = AVM_CICP_CP_UNSPECIFIED;
     ci_temp.color_info.matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
     ci_temp.color_info.transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
     ci_temp.color_info.full_range_flag = 0;
   }

   if (ci_temp.ci_chroma_sample_position_present_flag) {
     ci_temp.ci_chroma_sample_position[0] = avm_rb_read_uvlc(rb);
     if (ci_temp.ci_scan_type_idc != 1)
       ci_temp.ci_chroma_sample_position[1] = avm_rb_read_uvlc(rb);
     else
       ci_temp.ci_chroma_sample_position[1] =
           ci_temp.ci_chroma_sample_position[0];
   } else {
     ci_temp.ci_chroma_sample_position[0] = AVM_CSP_UNSPECIFIED;
     ci_temp.ci_chroma_sample_position[1] = AVM_CSP_UNSPECIFIED;
   }

   if (ci_temp.ci_aspect_ratio_info_present_flag) {
     av2_read_sample_aspect_ratio_information(&ci_temp, rb);
     if (!av2_set_sar_info(&ci_temp)) {
       avm_internal_error(&cm->error, AVM_CODEC_UNSUP_BITSTREAM,
                          "Incorrect SAR values");
     }
   }

   if (ci_temp.ci_timing_info_present_flag)
     av2_read_timing_info_header(&ci_temp.timing_info, &cm->error, rb);

 #if CONFIG_F414_OBU_EXTENSION
   // The +1 to account for the extension bit read before
   size_t bits_before_ext = rb->bit_offset - saved_bit_offset - 1;
   if (ci_temp.ci_extension_present_flag) {
     // Extension data bits = total - bits_read_before_extension -1 (ext flag)
     // - trailing bits
     int extension_bits = read_obu_extension_bits(
         rb->bit_buffer, rb->bit_buffer_end - rb->bit_buffer, bits_before_ext,
         &cm->error);
     if (extension_bits > 0) {
       rb->bit_offset += extension_bits;  // skip over the extension bits
     } else {
       // No extension data present
     }
   }
 #endif  // CONFIG_F414_OBU_EXTENSION
   if (av2_check_trailing_bits(pbi, rb) != 0) {
     // cm->error.error_code is already set.
     return 0;
   }

   //  * 0. CLK/OLK signalled without CI
   //  * 1. CI obu signalled without CLK/OLK
   //  * 2. CI obu signalled with CLK/OLK
   if (pbi->ci_and_key_per_layer[obu_mlayer_id] != 0) {
     // Check if a CI OBU has already been received for this embedded layer
     if (pbi->ci_obu_received_per_layer[obu_mlayer_id] ||
         (pbi->ci_and_key_per_layer[obu_mlayer_id] == 1)) {
       if (!av2_ci_params_identical(&cm->ci_params_per_layer[obu_mlayer_id],
                                    &ci_temp)) {
         avm_internal_error(
             &cm->error, AVM_CODEC_CORRUPT_FRAME,
             "Multiple CI OBUs in embedded layer must be identical.");
       }
       // CI obu matches the previous one, so no need to update
     } else {
       // Got the first CI Obu for this layer.
       cm->ci_params_per_layer[obu_mlayer_id] = ci_temp;
       pbi->ci_obu_received_per_layer[obu_mlayer_id] = 1;
     }
   }

   return ((rb->bit_offset - saved_bit_offset + 7) >> 3);
 }
	/*
	* Copyright (c) 2025, Alliance for Open Media. All rights reserved
	*
	* This source code is subject to the terms of the BSD 3-Clause Clear License
	* and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
	* License was not distributed with this source code in the LICENSE file, you
	* can obtain it at aomedia.org/license/software-license/bsd-3-c-c/. 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
	* aomedia.org/license/patent-license/.
	*/

	#include <assert.h>

	#include "config/avm_config.h"
	#include "config/avm_scale_rtcd.h"
	#include "avm/avm_codec.h"
	#include "avm_dsp/bitreader_buffer.h"
	#include "avm_ports/mem_ops.h"
	#include "av2/common/common.h"
	#include "av2/common/obu_util.h"
	#include "av2/common/timing.h"
	#include "av2/decoder/decoder.h"
	#include "av2/decoder/decodeframe.h"
	#include "av2/decoder/obu.h"
	#include "av2/common/av2_common_int.h"

	static void av2_set_color_info(ContentInterpretation *ci_params) {
	assert(ci_params->color_info.color_description_idc !=
	AVM_COLOR_DESC_IDC_EXPLICIT);
	switch (ci_params->color_info.color_description_idc) {
	case AVM_COLOR_DESC_IDC_BT709SDR:
	ci_params->color_info.color_primaries = AVM_CICP_CP_BT_709;
	ci_params->color_info.transfer_characteristics = AVM_CICP_TC_BT_709;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_470_B_G;
	break;
	case AVM_COLOR_DESC_IDC_BT2100PQ:
	ci_params->color_info.color_primaries = AVM_CICP_CP_BT_2020;
	ci_params->color_info.transfer_characteristics = AVM_CICP_TC_SMPTE_2084;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_2020_NCL;
	break;
	case AVM_COLOR_DESC_IDC_BT2100HLG:
	ci_params->color_info.color_primaries = AVM_CICP_CP_BT_2020;
	ci_params->color_info.transfer_characteristics =
	AVM_CICP_TC_BT_2020_10_BIT;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_2020_NCL;
	break;
	case AVM_COLOR_DESC_IDC_SRGB:
	ci_params->color_info.color_primaries = AVM_CICP_CP_BT_709;
	ci_params->color_info.transfer_characteristics = AVM_CICP_TC_SRGB;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_IDENTITY;
	break;
	case AVM_COLOR_DESC_IDC_SRGBSYCC:
	ci_params->color_info.color_primaries = AVM_CICP_CP_BT_709;
	ci_params->color_info.transfer_characteristics = AVM_CICP_TC_SRGB;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_BT_470_B_G;
	break;
	default:
	ci_params->color_info.color_primaries = AVM_CICP_CP_UNSPECIFIED;
	ci_params->color_info.transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
	break;
	}
	}

	static int av2_set_sar_info(ContentInterpretation *ci_params) {
	int supported_sample_aspect_ratio = 1;
	switch (ci_params->sar_info.sar_aspect_ratio_idc) {
	case AVM_SAR_IDC_UNSPECIFIED:
	case AVM_SAR_IDC_255: break;
	case AVM_SAR_IDC_1_TO_1:
	ci_params->sar_info.sar_width = 1;
	ci_params->sar_info.sar_height = 1;
	break;
	case AVM_SAR_IDC_12_TO_11:
	ci_params->sar_info.sar_width = 12;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_10_TO_11:
	ci_params->sar_info.sar_width = 10;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_16_TO_11:
	ci_params->sar_info.sar_width = 16;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_40_TO_33:
	ci_params->sar_info.sar_width = 40;
	ci_params->sar_info.sar_height = 33;
	break;
	case AVM_SAR_IDC_24_TO_11:
	ci_params->sar_info.sar_width = 24;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_20_TO_11:
	ci_params->sar_info.sar_width = 20;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_32_TO_11:
	ci_params->sar_info.sar_width = 32;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_80_TO_33:
	ci_params->sar_info.sar_width = 80;
	ci_params->sar_info.sar_height = 33;
	break;
	case AVM_SAR_IDC_18_TO_11:
	ci_params->sar_info.sar_width = 18;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_15_TO_11:
	ci_params->sar_info.sar_width = 15;
	ci_params->sar_info.sar_height = 11;
	break;
	case AVM_SAR_IDC_64_TO_33:
	ci_params->sar_info.sar_width = 64;
	ci_params->sar_info.sar_height = 33;
	break;
	case AVM_SAR_IDC_160_TO_99:
	ci_params->sar_info.sar_width = 160;
	ci_params->sar_info.sar_height = 99;
	break;
	case AVM_SAR_IDC_4_TO_3:
	ci_params->sar_info.sar_width = 4;
	ci_params->sar_info.sar_height = 3;
	break;
	case AVM_SAR_IDC_3_TO_2:
	ci_params->sar_info.sar_width = 3;
	ci_params->sar_info.sar_height = 2;
	break;
	case AVM_SAR_IDC_2_TO_1:
	ci_params->sar_info.sar_width = 2;
	ci_params->sar_info.sar_height = 1;
	break;
	default: supported_sample_aspect_ratio = 0; break;
	}
	return supported_sample_aspect_ratio;
	}

	static INLINE void av2_read_color_info(struct ContentInterpretation *ci_params,
	struct avm_read_bit_buffer *rb) {
	ColorInfo *col_info = &ci_params->color_info;
	col_info->color_description_idc = avm_rb_read_rice_golomb(rb, 2);

	if (col_info->color_description_idc == AVM_COLOR_DESC_IDC_EXPLICIT) {
	col_info->color_primaries = avm_rb_read_literal(rb, 8);
	col_info->transfer_characteristics = avm_rb_read_literal(rb, 8);
	col_info->matrix_coefficients = avm_rb_read_literal(rb, 8);
	} else {
	col_info->color_primaries = AVM_CICP_CP_UNSPECIFIED;
	col_info->transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
	col_info->matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
	}
	col_info->full_range_flag = avm_rb_read_bit(rb);
	}

	static INLINE void av2_read_sample_aspect_ratio_information(
	struct ContentInterpretation ci_params, struct avm_read_bit_buffer rb) {
	SarInfo *sar_info = &ci_params->sar_info;
	sar_info->sar_aspect_ratio_idc = avm_rb_read_literal(rb, 8);
	if (sar_info->sar_aspect_ratio_idc == AVM_SAR_IDC_255) {
	sar_info->sar_width = avm_rb_read_uvlc(rb);
	sar_info->sar_height = avm_rb_read_uvlc(rb);
	}
	}

	void av2_init_ci_params(ContentInterpretation *ci_params) {
	memset(ci_params, 0, sizeof(ContentInterpretation));
	ci_params->ci_chroma_sample_position[0] = AVM_CSP_UNSPECIFIED;
	ci_params->ci_chroma_sample_position[1] = AVM_CSP_UNSPECIFIED;
	ci_params->color_info.color_primaries = AVM_CICP_CP_UNSPECIFIED;
	ci_params->color_info.transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
	ci_params->color_info.matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
	}

	static int av2_ci_params_identical(const ContentInterpretation *ci1,
	const ContentInterpretation *ci2) {
	if (!memcmp(ci1, ci2, sizeof(ContentInterpretation))) return 1;
	return 0;
	}

	uint32_t av2_read_content_interpretation_obu(struct AV2Decoder *pbi,
	struct avm_read_bit_buffer *rb) {
	AV2_COMMON *const cm = &pbi->common;
	const int obu_mlayer_id = cm->mlayer_id;
	const uint32_t saved_bit_offset = rb->bit_offset;
	cm->error.error_code = AVM_CODEC_OK;
	assert(rb->error_handler);

	// Parse CI OBU into a temp structure
	ContentInterpretation ci_temp;
	av2_init_ci_params(&ci_temp);
	ci_temp.ci_scan_type_idc = avm_rb_read_literal(rb, 2);
	ci_temp.ci_color_description_present_flag = avm_rb_read_bit(rb);
	ci_temp.ci_chroma_sample_position_present_flag = avm_rb_read_bit(rb);
	ci_temp.ci_aspect_ratio_info_present_flag = avm_rb_read_bit(rb);
	ci_temp.ci_timing_info_present_flag = avm_rb_read_bit(rb);
	ci_temp.ci_extension_present_flag = avm_rb_read_bit(rb);
	(void)avm_rb_read_bit(rb); // ci_reserved_1bit

	if (ci_temp.ci_color_description_present_flag) {
	av2_read_color_info(&ci_temp, rb);
	if (ci_temp.color_info.color_description_idc != AVM_COLOR_DESC_IDC_EXPLICIT)
	av2_set_color_info(&ci_temp);
	} else {
	ci_temp.color_info.color_primaries = AVM_CICP_CP_UNSPECIFIED;
	ci_temp.color_info.matrix_coefficients = AVM_CICP_MC_UNSPECIFIED;
	ci_temp.color_info.transfer_characteristics = AVM_CICP_TC_UNSPECIFIED;
	ci_temp.color_info.full_range_flag = 0;
	}

	if (ci_temp.ci_chroma_sample_position_present_flag) {
	ci_temp.ci_chroma_sample_position[0] = avm_rb_read_uvlc(rb);
	if (ci_temp.ci_scan_type_idc != 1)
	ci_temp.ci_chroma_sample_position[1] = avm_rb_read_uvlc(rb);
	else
	ci_temp.ci_chroma_sample_position[1] =
	ci_temp.ci_chroma_sample_position[0];
	} else {
	ci_temp.ci_chroma_sample_position[0] = AVM_CSP_UNSPECIFIED;
	ci_temp.ci_chroma_sample_position[1] = AVM_CSP_UNSPECIFIED;
	}

	if (ci_temp.ci_aspect_ratio_info_present_flag) {
	av2_read_sample_aspect_ratio_information(&ci_temp, rb);
	if (!av2_set_sar_info(&ci_temp)) {
	avm_internal_error(&cm->error, AVM_CODEC_UNSUP_BITSTREAM,
	"Incorrect SAR values");
	}
	}

	if (ci_temp.ci_timing_info_present_flag)
	av2_read_timing_info_header(&ci_temp.timing_info, &cm->error, rb);

	#if CONFIG_F414_OBU_EXTENSION
	// The +1 to account for the extension bit read before
	size_t bits_before_ext = rb->bit_offset - saved_bit_offset - 1;
	if (ci_temp.ci_extension_present_flag) {
	// Extension data bits = total - bits_read_before_extension -1 (ext flag)
	// - trailing bits
	int extension_bits = read_obu_extension_bits(
	rb->bit_buffer, rb->bit_buffer_end - rb->bit_buffer, bits_before_ext,
	&cm->error);
	if (extension_bits > 0) {
	rb->bit_offset += extension_bits; // skip over the extension bits
	} else {
	// No extension data present
	}
	}
	#endif // CONFIG_F414_OBU_EXTENSION
	if (av2_check_trailing_bits(pbi, rb) != 0) {
	// cm->error.error_code is already set.
	return 0;
	}

	// * 0. CLK/OLK signalled without CI
	// * 1. CI obu signalled without CLK/OLK
	// * 2. CI obu signalled with CLK/OLK
	if (pbi->ci_and_key_per_layer[obu_mlayer_id] != 0) {
	// Check if a CI OBU has already been received for this embedded layer
	if (pbi->ci_obu_received_per_layer[obu_mlayer_id] \|\|
	(pbi->ci_and_key_per_layer[obu_mlayer_id] == 1)) {
	if (!av2_ci_params_identical(&cm->ci_params_per_layer[obu_mlayer_id],
	&ci_temp)) {
	avm_internal_error(
	&cm->error, AVM_CODEC_CORRUPT_FRAME,
	"Multiple CI OBUs in embedded layer must be identical.");
	}
	// CI obu matches the previous one, so no need to update
	} else {
	// Got the first CI Obu for this layer.
	cm->ci_params_per_layer[obu_mlayer_id] = ci_temp;
	pbi->ci_obu_received_per_layer[obu_mlayer_id] = 1;
	}
	}

	return ((rb->bit_offset - saved_bit_offset + 7) >> 3);
	}