xref: /aosp_15_r20/external/libavc/encoder/svc/isvce_cavlc.c (revision 495ae853bb871d1e5a258cb02c2cc13cde8ddb9a)

/******************************************************************************
 *
 * Copyright (C) 2022 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *****************************************************************************
 * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
 */

/**
*******************************************************************************
* @file
*  isvce_cavlc.c
*
* @brief
*  Contains all the routines to code syntax elements and residuals when entropy
*  coding chosen is CAVLC
*
* @author
*  ittiam
*
* @par List of Functions:
*  - isvce_compute_zeroruns_and_trailingones()
*  - isvce_write_coeff4x4_cavlc()
*  - isvce_write_coeff8x8_cavlc()
*  - isvce_encode_residue()
*  - isvce_write_islice_mb_cavlc()
*  - isvce_write_pslice_mb_cavlc()
*
* @remarks
*  None
*
*******************************************************************************
*/

/*****************************************************************************/
/* File Includes                                                             */
/*****************************************************************************/

/* System include files */
#include <stdio.h>
#include <assert.h>
#include <limits.h>

/* User include files */
#include "ih264e_config.h"
#include "ih264_typedefs.h"
#include "iv2.h"
#include "ive2.h"
#include "ih264_debug.h"
#include "isvc_macros.h"
#include "isvc_defs.h"
#include "isvce_defs.h"
#include "ih264e_error.h"
#include "ih264e_bitstream.h"
#include "ime_distortion_metrics.h"
#include "ime_defs.h"
#include "ime_structs.h"
#include "ih264_error.h"
#include "isvc_structs.h"
#include "isvc_trans_quant_itrans_iquant.h"
#include "isvc_inter_pred_filters.h"
#include "isvc_mem_fns.h"
#include "ih264_padding.h"
#include "ih264_intra_pred_filters.h"
#include "ih264_deblk_edge_filters.h"
#include "isvc_cabac_tables.h"
#include "irc_cntrl_param.h"
#include "irc_frame_info_collector.h"
#include "isvce_rate_control.h"
#include "isvce_cabac_structs.h"
#include "isvce_structs.h"
#include "isvce_encode_header.h"
#include "ih264_cavlc_tables.h"
#include "isvce_cavlc.h"
#include "ih264e_statistics.h"
#include "ih264e_trace.h"
#include "isvce_encode_header.h"
#include "isvce_utils.h"

/*****************************************************************************/
/* Function Definitions                                                      */
/*****************************************************************************/

/**
*******************************************************************************
*
* @brief
*  This function computes run of zero, number of trailing ones and sign of
*  trailing ones basing on the significant coeff map, residual block and
*  total nnz.
*
* @param[in] pi2_res_block
*  Pointer to residual block containing levels in scan order
*
* @param[in] u4_total_coeff
*  Total non-zero coefficients in that sub block
*
* @param[in] pu1_zero_run
*  Pointer to array to store run of zeros
*
* @param[in] u4_sig_coeff_map
*  significant coefficient map
*
* @returns u4_totzero_sign_trailone
*  Bits 0-8 contains number of trailing ones.
*  Bits 8-16 contains bitwise sign information of trailing one
*  Bits 16-24 contains total number of zeros.
*
* @remarks
*  None
*
*******************************************************************************
*/
static UWORD32 isvce_compute_zeroruns_and_trailingones(WORD16 *pi2_res_block,
                                                       UWORD32 u4_total_coeff, UWORD8 *pu1_zero_run,
                                                       UWORD32 u4_sig_coeff_map)
{
    UWORD32 i = 0;
    UWORD32 u4_nnz_coeff = 0;
    WORD32 i4_run = -1;
    UWORD32 u4_sign = 0;
    UWORD32 u4_tot_zero = 0;
    UWORD32 u4_trailing1 = 0;
    WORD32 i4_val;
    UWORD32 u4_totzero_sign_trailone;
    UWORD32 *pu4_zero_run;

    pu4_zero_run = (void *) pu1_zero_run;
    pu4_zero_run[0] = 0;
    pu4_zero_run[1] = 0;
    pu4_zero_run[2] = 0;
    pu4_zero_run[3] = 0;

    /* Compute Runs of zeros for all nnz coefficients except the last 3 */
    if(u4_total_coeff > 3)
    {
        for(i = 0; u4_nnz_coeff < (u4_total_coeff - 3); i++)
        {
            i4_run++;

            i4_val = (u4_sig_coeff_map & 0x1);
            u4_sig_coeff_map >>= 1;

            if(i4_val != 0)
            {
                pu1_zero_run[u4_nnz_coeff++] = i4_run;
                i4_run = -1;
            }
        }
    }

    /* Compute T1's, Signof(T1's) and Runs of zeros for the last 3 */
    while(u4_nnz_coeff != u4_total_coeff)
    {
        i4_run++;

        i4_val = (u4_sig_coeff_map & 0x1);
        u4_sig_coeff_map >>= 1;

        if(i4_val != 0)
        {
            if(pi2_res_block[u4_nnz_coeff] == 1)
            {
                pu1_zero_run[u4_nnz_coeff] = i4_run;
                u4_trailing1++;
            }
            else
            {
                if(pi2_res_block[u4_nnz_coeff] == -1)
                {
                    pu1_zero_run[u4_nnz_coeff] = i4_run;
                    u4_sign |= 1 << u4_trailing1;
                    u4_trailing1++;
                }
                else
                {
                    pu1_zero_run[u4_nnz_coeff] = i4_run;
                    u4_trailing1 = 0;
                    u4_sign = 0;
                }
            }
            i4_run = -1;
            u4_nnz_coeff++;
        }
        i++;
    }

    u4_tot_zero = i - u4_total_coeff;
    u4_totzero_sign_trailone = (u4_tot_zero << 16) | (u4_sign << 8) | u4_trailing1;

    return (u4_totzero_sign_trailone);
}

/**
*******************************************************************************
*
* @brief
*  This function generates CAVLC coded bit stream for the given residual block
*
* @param[in] pi2_res_block
*  Pointer to residual block containing levels in scan order
*
* @param[in] u4_total_coeff
*  Total non-zero coefficients in the sub block
*
* @param[in] u4_block_type
*  block type
*
* @param[in] pu1_zero_run
*  Pointer to array to store run of zeros
*
* @param[in] u4_nc
*  average of non zero coeff from top and left blocks (when available)
*
* @param[in, out] ps_bit_stream
*  structure pointing to a buffer holding output bit stream
*
* @param[in] u4_sig_coeff_map
*  significant coefficient map of the residual block
*
* @returns
*  error code
*
* @remarks
*  If the block type is CAVLC_CHROMA_4x4_DC, then u4_nc is non-significant
*
*******************************************************************************
*/
static IH264E_ERROR_T isvce_write_coeff4x4_cavlc(WORD16 *pi2_res_block, UWORD32 u4_total_coeff,
                                                 ENTROPY_BLK_TYPE u4_block_type,
                                                 UWORD8 *pu1_zero_run, UWORD32 u4_nc,
                                                 bitstrm_t *ps_bit_stream, UWORD32 u4_sig_coeff_map)
{
    IH264E_ERROR_T error_status = IH264E_SUCCESS;
    UWORD32 u4_totzero_sign_trailone = 0;
    UWORD32 u4_trailing_ones = 0;
    UWORD32 u4_tot_zeros = 0;
    UWORD32 u4_remaining_coeff = 0;
    UWORD32 u4_sign1 = 0;
    UWORD32 u4_max_num_coeff = 0;
    const UWORD32 au4_max_num_nnz_coeff[] = {16, 15, 16, 4, 15};

    /* validate inputs */
    ASSERT(u4_block_type <= CAVLC_CHROMA_4x4_AC);

    u4_max_num_coeff = au4_max_num_nnz_coeff[u4_block_type];

    ASSERT(u4_total_coeff <= u4_max_num_coeff);

    if(!u4_total_coeff)
    {
        UWORD32 u4_codeword = 15;
        UWORD32 u4_codesize = 1;
        if(u4_block_type == CAVLC_CHROMA_4x4_DC)
        {
            u4_codeword = 1;
            u4_codesize = 2;
            DEBUG("\n[%d numcoeff, %d numtrailing ones]", u4_total_coeff, 0);
            ENTROPY_TRACE("\tnumber of non zero coeffs ", u4_total_coeff);
            ENTROPY_TRACE("\tnumber of trailing ones ", 0);
        }
        else
        {
            UWORD32 u4_vlcnum = u4_nc >> 1;

            /* write coeff_token */
            if(u4_vlcnum > 3)
            {
                /* Num-FLC */
                u4_codeword = 3;
                u4_codesize = 6;
            }
            else
            {
                /* Num-VLC 0, 1, 2 */
                if(u4_vlcnum > 1)
                {
                    u4_vlcnum = 2;
                }
                u4_codesize <<= u4_vlcnum;
                u4_codeword >>= (4 - u4_codesize);
            }

            DEBUG("\n[%d numcoeff, %d numtrailing ones, %d nnz]", u4_total_coeff, 0, u4_nc);
            ENTROPY_TRACE("\tnumber of non zero coeffs ", u4_total_coeff);
            ENTROPY_TRACE("\tnC ", u4_nc);
        }

        DEBUG("\nCOEFF TOKEN 0: %d u4_codeword, %d u4_codesize", u4_codeword, u4_codesize);
        ENTROPY_TRACE("\tcodeword ", u4_codeword);
        ENTROPY_TRACE("\tcodesize ", u4_codesize);

        error_status = ih264e_put_bits(ps_bit_stream, u4_codeword, u4_codesize);

        return error_status;
    }
    else
    {
        /* Compute zero run, number of trailing ones and their sign. */
        u4_totzero_sign_trailone = isvce_compute_zeroruns_and_trailingones(
            pi2_res_block, u4_total_coeff, pu1_zero_run, u4_sig_coeff_map);
        u4_trailing_ones = u4_totzero_sign_trailone & 0xFF;
        u4_sign1 = (u4_totzero_sign_trailone >> 8) & 0xFF;
        u4_tot_zeros = (u4_totzero_sign_trailone >> 16) & 0xFF;
        u4_remaining_coeff = u4_total_coeff - u4_trailing_ones;

        /* write coeff_token */
        {
            UWORD32 u4_codeword;
            UWORD32 u4_codesize;
            if(u4_block_type == CAVLC_CHROMA_4x4_DC)
            {
                u4_codeword =
                    gu1_code_coeff_token_table_chroma[u4_trailing_ones][u4_total_coeff - 1];
                u4_codesize =
                    gu1_size_coeff_token_table_chroma[u4_trailing_ones][u4_total_coeff - 1];

                DEBUG("\n[%d numcoeff, %d numtrailing ones]", u4_total_coeff, u4_trailing_ones);
                ENTROPY_TRACE("\tnumber of non zero coeffs ", u4_total_coeff);
                ENTROPY_TRACE("\tnumber of trailing ones ", u4_trailing_ones);
            }
            else
            {
                UWORD32 u4_vlcnum = u4_nc >> 1;

                if(u4_vlcnum > 3)
                {
                    /* Num-FLC */
                    u4_codeword = ((u4_total_coeff - 1) << 2) + u4_trailing_ones;
                    u4_codesize = 6;
                }
                else
                {
                    /* Num-VLC 0, 1, 2 */
                    if(u4_vlcnum > 1)
                    {
                        u4_vlcnum = 2;
                    }
                    u4_codeword =
                        gu1_code_coeff_token_table[u4_vlcnum][u4_trailing_ones][u4_total_coeff - 1];
                    u4_codesize =
                        gu1_size_coeff_token_table[u4_vlcnum][u4_trailing_ones][u4_total_coeff - 1];
                }

                DEBUG("\n[%d numcoeff, %d numtrailing ones, %d nnz]", u4_total_coeff,
                      u4_trailing_ones, u4_nc);
                ENTROPY_TRACE("\tnumber of non zero coeffs ", u4_total_coeff);
                ENTROPY_TRACE("\tnumber of trailing ones ", u4_trailing_ones);
                ENTROPY_TRACE("\tnC ", u4_nc);
            }

            DEBUG("\nCOEFF TOKEN 0: %d u4_codeword, %d u4_codesize", u4_codeword, u4_codesize);
            ENTROPY_TRACE("\tcodeword ", u4_codeword);
            ENTROPY_TRACE("\tcodesize ", u4_codesize);

            error_status = ih264e_put_bits(ps_bit_stream, u4_codeword, u4_codesize);
        }

        /* write sign of trailing ones */
        if(u4_trailing_ones)
        {
            DEBUG("\nT1's: %d u4_codeword, %d u4_codesize", u4_sign1, u4_trailing_ones);
            error_status = ih264e_put_bits(ps_bit_stream, u4_sign1, u4_trailing_ones);
            ENTROPY_TRACE("\tnumber of trailing ones ", u4_trailing_ones);
            ENTROPY_TRACE("\tsign of trailing ones ", u4_sign1);
        }

        /* write level codes */
        if(u4_remaining_coeff)
        {
            WORD32 i4_level = pi2_res_block[u4_remaining_coeff - 1];
            UWORD32 u4_escape;
            UWORD32 u4_suffix_length = 0;  // Level-VLC[N]
            UWORD32 u4_abs_level, u4_abs_level_actual = 0;
            WORD32 i4_sign;
            const UWORD32 u4_rndfactor[] = {0, 0, 1, 3, 7, 15, 31};

            DEBUG("\n \t%d coeff,", i4_level);
            ENTROPY_TRACE("\tcoeff ", i4_level);

            if(u4_trailing_ones < 3)
            {
                /* If there are less than 3 T1s, then the first non-T1 level is
                 * incremented if negative (decremented if positive)*/
                if(i4_level < 0)
                {
                    i4_level += 1;
                }
                else
                {
                    i4_level -= 1;
                }

                u4_abs_level_actual = 1;

                /* Initialize VLC table (Suffix Length) to encode the level */
                if(u4_total_coeff > 10)
                {
                    u4_suffix_length = 1;
                }
            }

            i4_sign = (i4_level >> (sizeof(WORD32) * CHAR_BIT - 1));
            u4_abs_level = ((i4_level + i4_sign) ^ i4_sign);

            u4_abs_level_actual += u4_abs_level;

            u4_escape = (u4_abs_level + u4_rndfactor[u4_suffix_length]) >> u4_suffix_length;

            while(1)
            {
                UWORD32 u4_codesize;
                UWORD32 u4_codeword;
                UWORD32 u4_codeval;

                u4_remaining_coeff--;

                GATHER_CAVLC_STATS1();

                {
                    u4_codeval = u4_abs_level << 1;
                    u4_codeval = u4_codeval - 2 - i4_sign;

                    if((!u4_suffix_length) && (u4_escape > 7) && (u4_abs_level < 16))
                    {
                        u4_codeword = (1 << 4) + (u4_codeval - 14);
                        u4_codesize = 19;
                    }
                    else if(u4_escape > 7)
                    {
                        u4_codeword = (1 << 12) + (u4_codeval - (15 << u4_suffix_length));
                        u4_codesize = 28;
                        if(!u4_suffix_length)
                        {
                            u4_codeword -= 15;
                        }
                    }
                    else
                    {
                        u4_codeword =
                            (1 << u4_suffix_length) + (u4_codeval & ((1 << u4_suffix_length) - 1));
                        u4_codesize = (u4_codeval >> u4_suffix_length) + 1 + u4_suffix_length;
                    }
                }

                /*put the level code in bitstream*/
                DEBUG("\nLEVEL: %d u4_codeword, %d u4_codesize", u4_codeword, u4_codesize);
                ENTROPY_TRACE("\tcodeword ", u4_codeword);
                ENTROPY_TRACE("\tcodesize ", u4_codesize);
                error_status = ih264e_put_bits(ps_bit_stream, u4_codeword, u4_codesize);

                if(u4_remaining_coeff == 0) break;

                /*update suffix length for next level*/
                if(u4_suffix_length == 0)
                {
                    u4_suffix_length++;
                }
                if(u4_suffix_length < 6)
                {
                    if(u4_abs_level_actual > gu1_threshold_vlc_level[u4_suffix_length])
                    {
                        u4_suffix_length++;
                    }
                }

                /* next level */
                i4_level = pi2_res_block[u4_remaining_coeff - 1];

                DEBUG("\n \t%d coeff,", i4_level);
                ENTROPY_TRACE("\tcoeff ", i4_level);

                i4_sign = (i4_level >> (sizeof(WORD32) * CHAR_BIT - 1));
                u4_abs_level = ((i4_level + i4_sign) ^ i4_sign);

                u4_abs_level_actual = u4_abs_level;

                u4_escape = (u4_abs_level + u4_rndfactor[u4_suffix_length]) >> u4_suffix_length;
            }
        }

        DEBUG("\n \t %d totalzeros", u4_tot_zeros);
        ENTROPY_TRACE("\ttotal zeros ", u4_tot_zeros);

        /* Write Total Zeros */
        if(u4_total_coeff < u4_max_num_coeff)
        {
            WORD32 index;
            UWORD32 u4_codeword;
            UWORD32 u4_codesize;

            if(u4_block_type == CAVLC_CHROMA_4x4_DC)
            {
                UWORD8 gu1_index_zero_table_chroma[] = {0, 4, 7};
                index = gu1_index_zero_table_chroma[u4_total_coeff - 1] + u4_tot_zeros;
                u4_codesize = gu1_size_zero_table_chroma[index];
                u4_codeword = gu1_code_zero_table_chroma[index];
            }
            else
            {
                index = gu1_index_zero_table[u4_total_coeff - 1] + u4_tot_zeros;
                u4_codesize = gu1_size_zero_table[index];
                u4_codeword = gu1_code_zero_table[index];
            }

            DEBUG("\nTOTAL ZEROS: %d u4_codeword, %d u4_codesize", u4_codeword, u4_codesize);
            ENTROPY_TRACE("\tcodeword ", u4_codeword);
            ENTROPY_TRACE("\tcodesize ", u4_codesize);
            error_status = ih264e_put_bits(ps_bit_stream, u4_codeword, u4_codesize);
        }

        /* Write Run Before */
        if(u4_tot_zeros)
        {
            UWORD32 u4_max_num_coef = u4_total_coeff - 1;
            UWORD32 u4_codeword;
            UWORD32 u4_codesize;
            UWORD32 u4_zeros_left = u4_tot_zeros;

            while(u4_max_num_coef)
            {
                UWORD32 u4_run_before = pu1_zero_run[u4_max_num_coef];
                UWORD32 u4_index;

                if(u4_zeros_left > MAX_ZERO_LEFT)
                {
                    u4_index = gu1_index_run_table[MAX_ZERO_LEFT];
                }
                else
                {
                    u4_index = gu1_index_run_table[u4_zeros_left - 1];
                }

                u4_codesize = gu1_size_run_table[u4_index + u4_run_before];
                u4_codeword = gu1_code_run_table[u4_index + u4_run_before];

                DEBUG("\nRUN BEFORE ZEROS: %d u4_codeword, %d u4_codesize", u4_codeword,
                      u4_codesize);
                ENTROPY_TRACE("\tcodeword ", u4_codeword);
                ENTROPY_TRACE("\tcodesize ", u4_codesize);
                error_status = ih264e_put_bits(ps_bit_stream, u4_codeword, u4_codesize);

                u4_zeros_left -= u4_run_before;
                if(!u4_zeros_left)
                {
                    break;
                }
                u4_max_num_coef--;
            }
        }
    }

    return error_status;
}

/**
*******************************************************************************
*
* @brief
*  This function generates CAVLC coded bit stream for the given subblock
*
* @param[in] ps_ent_ctxt
*  Pointer to entropy context
*
* @param[in] pi2_res_block
*  Pointers to residual blocks of all the partitions for the current subblk
*  (containing levels in scan order)
*
* @param[in] pu1_nnz
*  Total non-zero coefficients of all the partitions for the current subblk
*
* @param[in] pu2_sig_coeff_map
*  Significant coefficient map of all the partitions for the current subblk
*
* @param[in] u4_block_type
*  entropy coding block type
*
* @param[in] u4_ngbr_avbl
*  top and left availability of all the partitions for the current subblk
*  (packed)
*
* @param[in] pu1_top_nnz
*  pointer to the buffer containing nnz of all the subblks to the top
*
* @param[in] pu1_left_nnz
*  pointer to the buffer containing nnz of all the subblks to the left
*
* @returns error status
*
* @remarks none
*
*******************************************************************************
*/
static IH264E_ERROR_T isvce_write_coeff8x8_cavlc(isvce_entropy_ctxt_t *ps_ent_ctxt,
                                                 WORD16 **pi2_res_block, UWORD8 *pu1_nnz,
                                                 UWORD16 *pu2_sig_coeff_map,
                                                 ENTROPY_BLK_TYPE u4_block_type,
                                                 UWORD32 u4_ngbr_avlb, UWORD8 *pu1_top_nnz,
                                                 UWORD8 *pu1_left_nnz)
{
    IH264E_ERROR_T error_status = IH264E_SUCCESS;
    bitstrm_t *ps_bitstream = ps_ent_ctxt->ps_bitstrm;
    UWORD8 *pu1_zero_run = ps_ent_ctxt->au1_zero_run, *pu1_ngbr_avbl;
    UWORD32 u4_nC;
    UWORD8 u1_mb_a, u1_mb_b;

    pu1_ngbr_avbl = (void *) (&u4_ngbr_avlb);

    /* encode ac block index 4x4 = 0*/
    u1_mb_a = pu1_ngbr_avbl[0] & 0x0F;
    u1_mb_b = pu1_ngbr_avbl[0] & 0xF0;
    u4_nC = 0;
    if(u1_mb_a) u4_nC += pu1_left_nnz[0];
    if(u1_mb_b) u4_nC += pu1_top_nnz[0];
    if(u1_mb_a && u1_mb_b) u4_nC = (u4_nC + 1) >> 1;
    pu1_left_nnz[0] = pu1_top_nnz[0] = pu1_nnz[0];
    error_status =
        isvce_write_coeff4x4_cavlc(pi2_res_block[0], pu1_nnz[0], u4_block_type, pu1_zero_run, u4_nC,
                                   ps_bitstream, pu2_sig_coeff_map[0]);

    /* encode ac block index 4x4 = 1*/
    u1_mb_a = pu1_ngbr_avbl[1] & 0x0F;
    u1_mb_b = pu1_ngbr_avbl[1] & 0xF0;
    u4_nC = 0;
    if(u1_mb_a) u4_nC += pu1_left_nnz[0];
    if(u1_mb_b) u4_nC += pu1_top_nnz[1];
    if(u1_mb_a && u1_mb_b) u4_nC = (u4_nC + 1) >> 1;
    pu1_left_nnz[0] = pu1_top_nnz[1] = pu1_nnz[1];
    error_status =
        isvce_write_coeff4x4_cavlc(pi2_res_block[1], pu1_nnz[1], u4_block_type, pu1_zero_run, u4_nC,
                                   ps_bitstream, pu2_sig_coeff_map[1]);

    /* encode ac block index 4x4 = 2*/
    u1_mb_a = pu1_ngbr_avbl[2] & 0x0F;
    u1_mb_b = pu1_ngbr_avbl[2] & 0xF0;
    u4_nC = 0;
    if(u1_mb_a) u4_nC += pu1_left_nnz[1];
    if(u1_mb_b) u4_nC += pu1_top_nnz[0];
    if(u1_mb_a && u1_mb_b) u4_nC = (u4_nC + 1) >> 1;
    pu1_left_nnz[1] = pu1_top_nnz[0] = pu1_nnz[2];
    error_status =
        isvce_write_coeff4x4_cavlc(pi2_res_block[2], pu1_nnz[2], u4_block_type, pu1_zero_run, u4_nC,
                                   ps_bitstream, pu2_sig_coeff_map[2]);

    /* encode ac block index 4x4 = 0*/
    u1_mb_a = pu1_ngbr_avbl[3] & 0x0F;
    u1_mb_b = pu1_ngbr_avbl[3] & 0xF0;
    u4_nC = 0;
    if(u1_mb_a) u4_nC += pu1_left_nnz[1];
    if(u1_mb_b) u4_nC += pu1_top_nnz[1];
    if(u1_mb_a && u1_mb_b) u4_nC = (u4_nC + 1) >> 1;
    pu1_left_nnz[1] = pu1_top_nnz[1] = pu1_nnz[3];
    error_status =
        isvce_write_coeff4x4_cavlc(pi2_res_block[3], pu1_nnz[3], u4_block_type, pu1_zero_run, u4_nC,
                                   ps_bitstream, pu2_sig_coeff_map[3]);

    return error_status;
}

/**
*******************************************************************************
*
* @brief
*  This function encodes luma and chroma residues of a macro block when
*  the entropy coding mode chosen is cavlc.
*
* @param[in] ps_ent_ctxt
*  Pointer to entropy context
*
* @param[in] u4_mb_type
*  current mb type
*
* @param[in] u4_cbp
*  coded block pattern for the current mb
*
* @returns error code
*
* @remarks none
*
*******************************************************************************
*/
static IH264E_ERROR_T isvce_encode_residue(isvce_entropy_ctxt_t *ps_ent_ctxt, UWORD32 u4_mb_type,
                                           UWORD32 u4_cbp)
{
    /* error status */
    IH264E_ERROR_T error_status = IH264E_SUCCESS;

    /* packed residue */
    void *pv_mb_coeff_data = ps_ent_ctxt->pv_mb_coeff_data;

    /* bit stream buffer */
    bitstrm_t *ps_bitstream = ps_ent_ctxt->ps_bitstrm;

    /* zero run */
    UWORD8 *pu1_zero_run = ps_ent_ctxt->au1_zero_run;

    /* temp var */
    UWORD32 u4_nC, u4_ngbr_avlb;
    UWORD8 au1_nnz[4], *pu1_ngbr_avlb, *pu1_top_nnz, *pu1_left_nnz;
    UWORD16 au2_sig_coeff_map[4] = {0};
    WORD16 *pi2_res_block[4] = {NULL};
    UWORD8 *pu1_slice_idx = ps_ent_ctxt->pu1_slice_idx;
    tu_sblk_coeff_data_t *ps_mb_coeff_data;
    ENTROPY_BLK_TYPE e_entropy_blk_type = CAVLC_LUMA_4x4;

    /* ngbr availability */
    UWORD8 u1_mb_a, u1_mb_b;

    /* cbp */
    UWORD32 u4_cbp_luma = u4_cbp & 0xF, u4_cbp_chroma = u4_cbp >> 4;

    /* mb indices */
    WORD32 i4_mb_x, i4_mb_y;

    /* derive neighbor availability */
    i4_mb_x = ps_ent_ctxt->i4_mb_x;
    i4_mb_y = ps_ent_ctxt->i4_mb_y;
    pu1_slice_idx += (i4_mb_y * ps_ent_ctxt->i4_wd_mbs);
    /* left macroblock availability */
    u1_mb_a = (i4_mb_x == 0 || (pu1_slice_idx[i4_mb_x - 1] != pu1_slice_idx[i4_mb_x])) ? 0 : 1;
    /* top macroblock availability */
    u1_mb_b = (i4_mb_y == 0 ||
               (pu1_slice_idx[i4_mb_x - ps_ent_ctxt->i4_wd_mbs] != pu1_slice_idx[i4_mb_x]))
                  ? 0
                  : 1;

    pu1_ngbr_avlb = (void *) (&u4_ngbr_avlb);
    pu1_top_nnz = ps_ent_ctxt->pu1_top_nnz_luma[ps_ent_ctxt->i4_mb_x];
    pu1_left_nnz = (UWORD8 *) &ps_ent_ctxt->u4_left_nnz_luma;

    /* encode luma residue */

    /* mb type intra 16x16 */
    if(u4_mb_type == I16x16)
    {
        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        /* estimate nnz for the current mb */
        u4_nC = 0;
        if(u1_mb_a) u4_nC += pu1_left_nnz[0];
        if(u1_mb_b) u4_nC += pu1_top_nnz[0];
        if(u1_mb_a && u1_mb_b) u4_nC = (u4_nC + 1) >> 1;

        /* encode dc block */
        ENTROPY_TRACE("Luma DC blk idx %d", 0);
        error_status =
            isvce_write_coeff4x4_cavlc(pi2_res_block[0], au1_nnz[0], CAVLC_LUMA_4x4_DC,
                                       pu1_zero_run, u4_nC, ps_bitstream, au2_sig_coeff_map[0]);

        e_entropy_blk_type = CAVLC_LUMA_4x4_AC;
    }

    if(u4_cbp_luma & 1)
    {
        /* encode ac block index 8x8 = 0*/
        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[2],
                                   au2_sig_coeff_map[2], pi2_res_block[2]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[3],
                                   au2_sig_coeff_map[3], pi2_res_block[3]);
        /* derive sub block neighbor availability */

        pu1_ngbr_avlb[0] = (u1_mb_b << 4) | (u1_mb_a);
        pu1_ngbr_avlb[1] = (u1_mb_b << 4) | 1;
        pu1_ngbr_avlb[2] = (1 << 4) | (u1_mb_a);
        pu1_ngbr_avlb[3] = 0x11;
        /* encode sub blk */
        ENTROPY_TRACE("Luma blk idx %d", 0);
        error_status =
            isvce_write_coeff8x8_cavlc(ps_ent_ctxt, pi2_res_block, au1_nnz, au2_sig_coeff_map,
                                       e_entropy_blk_type, u4_ngbr_avlb, pu1_top_nnz, pu1_left_nnz);
    }
    else
    {
        pu1_top_nnz[0] = pu1_top_nnz[1] = 0;
        pu1_left_nnz[0] = pu1_left_nnz[1] = 0;
    }

    if(u4_cbp_luma & 2)
    {
        /* encode ac block index 8x8 = 1*/
        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[2],
                                   au2_sig_coeff_map[2], pi2_res_block[2]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[3],
                                   au2_sig_coeff_map[3], pi2_res_block[3]);

        /* derive sub block neighbor availability */
        pu1_ngbr_avlb[1] = pu1_ngbr_avlb[0] = (u1_mb_b << 4) | 1;
        pu1_ngbr_avlb[3] = pu1_ngbr_avlb[2] = 0x11;
        /* encode sub blk */
        ENTROPY_TRACE("Luma blk idx %d", 1);
        error_status = isvce_write_coeff8x8_cavlc(ps_ent_ctxt, pi2_res_block, au1_nnz,
                                                  au2_sig_coeff_map, e_entropy_blk_type,
                                                  u4_ngbr_avlb, pu1_top_nnz + 2, pu1_left_nnz);
    }
    else
    {
        (pu1_top_nnz + 2)[0] = (pu1_top_nnz + 2)[1] = 0;
        pu1_left_nnz[0] = pu1_left_nnz[1] = 0;
    }

    if(u4_cbp_luma & 0x4)
    {
        /* encode ac block index 8x8 = 2*/
        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[2],
                                   au2_sig_coeff_map[2], pi2_res_block[2]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[3],
                                   au2_sig_coeff_map[3], pi2_res_block[3]);

        /* derive sub block neighbor availability */
        pu1_ngbr_avlb[2] = pu1_ngbr_avlb[0] = (1 << 4) | u1_mb_a;
        pu1_ngbr_avlb[1] = pu1_ngbr_avlb[3] = 0x11;
        /* encode sub blk */
        ENTROPY_TRACE("Luma blk idx %d", 2);
        error_status = isvce_write_coeff8x8_cavlc(ps_ent_ctxt, pi2_res_block, au1_nnz,
                                                  au2_sig_coeff_map, e_entropy_blk_type,
                                                  u4_ngbr_avlb, pu1_top_nnz, (pu1_left_nnz + 2));
    }
    else
    {
        pu1_top_nnz[0] = pu1_top_nnz[1] = 0;
        (pu1_left_nnz + 2)[0] = (pu1_left_nnz + 2)[1] = 0;
    }

    if(u4_cbp_luma & 0x8)
    {
        /* encode ac block index 8x8 = 3*/
        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[2],
                                   au2_sig_coeff_map[2], pi2_res_block[2]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[3],
                                   au2_sig_coeff_map[3], pi2_res_block[3]);

        /* derive sub block neighbor availability */
        u4_ngbr_avlb = 0x11111111;
        /* encode sub blk */
        ENTROPY_TRACE("Luma blk idx %d", 3);
        error_status = isvce_write_coeff8x8_cavlc(ps_ent_ctxt, pi2_res_block, au1_nnz,
                                                  au2_sig_coeff_map, e_entropy_blk_type,
                                                  u4_ngbr_avlb, pu1_top_nnz + 2, pu1_left_nnz + 2);
    }
    else
    {
        (pu1_top_nnz + 2)[0] = (pu1_top_nnz + 2)[1] = 0;
        (pu1_left_nnz + 2)[0] = (pu1_left_nnz + 2)[1] = 0;
    }

    /* encode chroma residue */
    if(u4_cbp_chroma & 3)
    {
        /* parse packed coeff data structure for residual data */
        /* cb, cr */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);

        /* encode dc block */
        /* cb, cr */
        ENTROPY_TRACE("Chroma DC blk idx %d", 0);
        error_status =
            isvce_write_coeff4x4_cavlc(pi2_res_block[0], au1_nnz[0], CAVLC_CHROMA_4x4_DC,
                                       pu1_zero_run, 0, ps_bitstream, au2_sig_coeff_map[0]);
        ENTROPY_TRACE("Chroma DC blk idx %d", 1);
        error_status =
            isvce_write_coeff4x4_cavlc(pi2_res_block[1], au1_nnz[1], CAVLC_CHROMA_4x4_DC,
                                       pu1_zero_run, 0, ps_bitstream, au2_sig_coeff_map[1]);
    }

    pu1_top_nnz = ps_ent_ctxt->pu1_top_nnz_cbcr[ps_ent_ctxt->i4_mb_x];
    pu1_left_nnz = (UWORD8 *) &ps_ent_ctxt->u4_left_nnz_cbcr;

    /* encode sub blk */
    if(u4_cbp_chroma & 0x2)
    {
        /* encode ac block index 8x8 = 0*/
        /* derive sub block neighbor availability */
        pu1_ngbr_avlb[0] = (u1_mb_b << 4) | (u1_mb_a);
        pu1_ngbr_avlb[1] = (u1_mb_b << 4) | 1;
        pu1_ngbr_avlb[2] = (1 << 4) | (u1_mb_a);
        pu1_ngbr_avlb[3] = 0x11;

        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[2],
                                   au2_sig_coeff_map[2], pi2_res_block[2]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[3],
                                   au2_sig_coeff_map[3], pi2_res_block[3]);

        ENTROPY_TRACE("Chroma AC blk idx %d", 0);
        error_status = isvce_write_coeff8x8_cavlc(ps_ent_ctxt, pi2_res_block, au1_nnz,
                                                  au2_sig_coeff_map, CAVLC_CHROMA_4x4_AC,
                                                  u4_ngbr_avlb, pu1_top_nnz, pu1_left_nnz);
    }
    else
    {
        pu1_top_nnz[0] = pu1_top_nnz[1] = 0;
        pu1_left_nnz[0] = pu1_left_nnz[1] = 0;
    }

    pu1_top_nnz += 2;
    pu1_left_nnz += 2;

    /* encode sub blk */
    if(u4_cbp_chroma & 0x2)
    {
        /* parse packed coeff data structure for residual data */
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[0],
                                   au2_sig_coeff_map[0], pi2_res_block[0]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[1],
                                   au2_sig_coeff_map[1], pi2_res_block[1]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[2],
                                   au2_sig_coeff_map[2], pi2_res_block[2]);
        PARSE_COEFF_DATA_BLOCK_4x4(pv_mb_coeff_data, ps_mb_coeff_data, au1_nnz[3],
                                   au2_sig_coeff_map[3], pi2_res_block[3]);

        ENTROPY_TRACE("Chroma AC blk idx %d", 1);
        error_status = isvce_write_coeff8x8_cavlc(ps_ent_ctxt, pi2_res_block, au1_nnz,
                                                  au2_sig_coeff_map, CAVLC_CHROMA_4x4_AC,
                                                  u4_ngbr_avlb, pu1_top_nnz, pu1_left_nnz);
    }
    else
    {
        pu1_top_nnz[0] = pu1_top_nnz[1] = 0;
        pu1_left_nnz[0] = pu1_left_nnz[1] = 0;
    }

    /* store the index of the next mb coeff data */
    ps_ent_ctxt->pv_mb_coeff_data = pv_mb_coeff_data;

    return error_status;
}

/**
*******************************************************************************
*
* @brief
*  This function generates CAVLC coded bit stream for an Intra Slice.
*
* @description
*  The mb syntax layer for intra slices constitutes luma mb mode, luma sub modes
*  (if present), mb qp delta, coded block pattern, chroma mb mode and
*  luma/chroma residue. These syntax elements are written as directed by table
*  7.3.5 of h264 specification.
*
* @param[in] ps_ent_ctxt
*  pointer to entropy context
*
* @returns error code
*
* @remarks none
*
*******************************************************************************
*/
IH264E_ERROR_T isvce_write_islice_mb_cavlc(isvce_entropy_ctxt_t *ps_ent_ctxt)
{
    /* error status */
    IH264E_ERROR_T error_status = IH264E_SUCCESS;

    /* bit stream ptr */
    bitstrm_t *ps_bitstream = ps_ent_ctxt->ps_bitstrm;

    /* packed header data */
    UWORD8 *pu1_byte = ps_ent_ctxt->pv_mb_header_data;
    isvce_mb_hdr_common_t *ps_mb_hdr = (isvce_mb_hdr_common_t *) ps_ent_ctxt->pv_mb_header_data;

    /* mb header info */
    /*
     * mb_tpm : mb type plus mode
     * mb_type : luma mb type and chroma mb type are packed
     * cbp : coded block pattern
     * mb_qp_delta : mb qp delta
     * chroma_intra_mode : chroma intra mode
     * luma_intra_mode : luma intra mode
     */
    WORD32 mb_tpm, mb_type, cbp, chroma_intra_mode, luma_intra_mode;
    WORD8 mb_qp_delta;

    /* temp var */
    WORD32 i, mb_type_stream;

    WORD32 bitstream_start_offset, bitstream_end_offset;

    svc_slice_header_t *ps_svc_slice_header =
        ps_ent_ctxt->ps_svc_slice_hdr_base +
        (ps_ent_ctxt->i4_cur_slice_idx % SVC_MAX_SLICE_HDR_CNT);

    /* Starting bitstream offset for header in bits */
    bitstream_start_offset = isvce_get_num_bits(ps_bitstream);

    /********************************************************************/
    /*                    BEGIN HEADER GENERATION                       */
    /********************************************************************/

    if(ps_ent_ctxt->u1_spatial_layer_id && ps_svc_slice_header->i1_adaptive_base_mode_flag)
    {
        /* write base_mode_flag */
        PUT_BITS(ps_bitstream, ps_mb_hdr->u1_base_mode_flag, 1, error_status, "base_mode_flag");
    }
    else
    {
        ps_mb_hdr->u1_base_mode_flag = 0;
    }

    /* mb header info */
    mb_tpm = ps_mb_hdr->u1_mb_type_mode;
    cbp = ps_mb_hdr->u1_cbp;
    mb_qp_delta =
        ((WORD16) ps_mb_hdr->u1_mb_qp) - ((WORD16) ps_ent_ctxt->ps_mb_qp_ctxt->u1_cur_mb_qp);

    /* mb type */
    mb_type = mb_tpm & 0xF;
    /* is intra ? */
    if(!ps_mb_hdr->u1_base_mode_flag)
    {
        if(mb_type == I16x16)
        {
            UWORD32 u4_cbp_l, u4_cbp_c;

            u4_cbp_c = (cbp >> 4);
            u4_cbp_l = (cbp & 0xF);
            luma_intra_mode = (mb_tpm >> 4) & 3;
            chroma_intra_mode = (mb_tpm >> 6);

            mb_type_stream = luma_intra_mode + 1 + (u4_cbp_c << 2) + (u4_cbp_l == 15) * 12;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, mb_type_stream, error_status, "mb type");

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");

            pu1_byte += sizeof(isvce_mb_hdr_i16x16_t);
        }
        else if(mb_type == I4x4)
        {
            isvce_mb_hdr_i4x4_t *ps_mb_hdr_i4x4 =
                (isvce_mb_hdr_i4x4_t *) ps_ent_ctxt->pv_mb_header_data;

            /* mb sub blk modes */
            WORD32 intra_pred_mode_flag, rem_intra_mode;
            WORD32 byte;

            chroma_intra_mode = (mb_tpm >> 6);

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, 0, error_status, "mb type");

            for(i = 0; i < 16; i += 2)
            {
                /* sub blk idx 1 */
                byte = ps_mb_hdr_i4x4->au1_sub_blk_modes[i >> 1];

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }

                /* sub blk idx 2 */
                byte >>= 4;

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }
            }

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");

            pu1_byte += sizeof(isvce_mb_hdr_i4x4_t);
        }
        else if(mb_type == I8x8)
        {
            /* transform 8x8 flag */
            UWORD32 u4_transform_size_8x8_flag = ps_ent_ctxt->i1_transform_8x8_mode_flag;
            isvce_mb_hdr_i8x8_t *ps_mb_hdr_i8x8 =
                (isvce_mb_hdr_i8x8_t *) ps_ent_ctxt->pv_mb_header_data;

            /* mb sub blk modes */
            WORD32 intra_pred_mode_flag, rem_intra_mode;
            WORD32 byte;

            chroma_intra_mode = (mb_tpm >> 6);

            ASSERT(0);

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, 0, error_status, "mb type");

            /* u4_transform_size_8x8_flag */
            PUT_BITS(ps_bitstream, u4_transform_size_8x8_flag, 1, error_status,
                     "u4_transform_size_8x8_flag");

            /* write sub block modes */
            for(i = 0; i < 4; i++)
            {
                /* sub blk idx 1 */
                byte = ps_mb_hdr_i8x8->au1_sub_blk_modes[i >> 1];

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }

                /* sub blk idx 2 */
                byte >>= 4;

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }
            }

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");

            pu1_byte += sizeof(isvce_mb_hdr_i8x8_t);
        }
    }
    else
    {
        pu1_byte += sizeof(isvce_mb_hdr_base_mode_t);
    }

    /* coded_block_pattern */
    if(ps_mb_hdr->u1_base_mode_flag || mb_type != I16x16)
    {
        PUT_BITS_UEV(ps_bitstream, gu1_cbp_map_tables[cbp][ps_mb_hdr->u1_base_mode_flag],
                     error_status, "coded_block_pattern");

        if(cbp % 16 > 0 && ps_ent_ctxt->i1_transform_8x8_mode_flag &&
           (ps_mb_hdr->u1_base_mode_flag || (mb_type == I8x8 || mb_type == I4x4)))
        {
            PUT_BITS(ps_bitstream, ps_ent_ctxt->i1_transform_8x8_mode_flag, 1, error_status,
                     "u4_transform_size_8x8_flag");
        }
    }

    if((cbp > 0) || (mb_type == I16x16))
    {
        /* mb_qp_delta */
        PUT_BITS_SEV(ps_bitstream, mb_qp_delta, error_status, "mb_qp_delta");
        ps_ent_ctxt->ps_mb_qp_ctxt->u1_cur_mb_qp = ps_mb_hdr->u1_mb_qp;
    }

    /* Ending bitstream offset for header in bits */
    bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

    ps_ent_ctxt->u4_header_bits[0] += bitstream_end_offset - bitstream_start_offset;

    /* Starting bitstream offset for residue */
    bitstream_start_offset = bitstream_end_offset;

    /* residual */
    error_status = isvce_encode_residue(ps_ent_ctxt, mb_type, cbp);

    /* Ending bitstream offset for reside in bits */
    bitstream_end_offset = isvce_get_num_bits(ps_bitstream);
    ps_ent_ctxt->u4_residue_bits[0] += bitstream_end_offset - bitstream_start_offset;

    /* store the index of the next mb syntax layer */
    ps_ent_ctxt->pv_mb_header_data = pu1_byte;

    return error_status;
}

/**
*******************************************************************************
*
* @brief
*  This function generates CAVLC coded bit stream for Inter slices
*
* @description
*  The mb syntax layer for inter slices constitutes luma mb mode, luma sub modes
*  (if present), mb qp delta, coded block pattern, chroma mb mode and
*  luma/chroma residue. These syntax elements are written as directed by table
*  7.3.5 of h264 specification
*
* @param[in] ps_ent_ctxt
*  pointer to entropy context
*
* @returns error code
*
* @remarks none
*
*******************************************************************************
*/
IH264E_ERROR_T isvce_write_pslice_mb_cavlc(isvce_entropy_ctxt_t *ps_ent_ctxt)
{
    /* mb header info */
    /*
     * mb_tpm : mb type plus mode
     * mb_type : luma mb type and chroma mb type are packed
     * cbp : coded block pattern
     * mb_qp_delta : mb qp delta
     * chroma_intra_mode : chroma intra mode
     * luma_intra_mode : luma intra mode
     * ps_pu :  Pointer to the array of structures having motion vectors, size
     * and position of sub partitions
     */
    WORD32 mb_tpm, mb_type, cbp, chroma_intra_mode, luma_intra_mode;
    WORD8 mb_qp_delta;
    WORD32 i, mb_type_stream;
    WORD32 bitstream_start_offset, bitstream_end_offset;
    UWORD8 u1_is_intra_mb;

    bitstrm_t *ps_bitstream = ps_ent_ctxt->ps_bitstrm;
    isvce_mb_hdr_common_t *ps_mb_hdr = (isvce_mb_hdr_common_t *) ps_ent_ctxt->pv_mb_header_data;
    svc_slice_header_t *ps_svc_slice_header =
        ps_ent_ctxt->ps_svc_slice_hdr_base +
        (ps_ent_ctxt->i4_cur_slice_idx % SVC_MAX_SLICE_HDR_CNT);

    IH264E_ERROR_T error_status = IH264E_SUCCESS;

    UWORD8 *pu1_byte = ps_ent_ctxt->pv_mb_header_data;
    WORD32 cbptable = 1;
    WORD32 is_inter = 0;

    /* Starting bitstream offset for header in bits */
    bitstream_start_offset = isvce_get_num_bits(ps_bitstream);

    /********************************************************************/
    /*                    BEGIN HEADER GENERATION                       */
    /********************************************************************/

    /* mb header info */
    mb_tpm = ps_mb_hdr->u1_mb_type_mode;

    /* mb type */
    mb_type = mb_tpm & 0xF;
    u1_is_intra_mb = (mb_type == I16x16) || (mb_type == I8x8) || (mb_type == I4x4);

    /* check for skip */
    if(mb_type == PSKIP)
    {
        UWORD32 *nnz;

        is_inter = 1;

        /* increment skip counter */
        (*ps_ent_ctxt->pi4_mb_skip_run)++;

        /* store the index of the next mb syntax layer */
        pu1_byte += sizeof(isvce_mb_hdr_pskip_t);
        ps_ent_ctxt->pv_mb_header_data = pu1_byte;

        /* set nnz to zero */
        ps_ent_ctxt->u4_left_nnz_luma = 0;
        nnz = (UWORD32 *) ps_ent_ctxt->pu1_top_nnz_luma[ps_ent_ctxt->i4_mb_x];
        *nnz = 0;
        ps_ent_ctxt->u4_left_nnz_cbcr = 0;
        nnz = (UWORD32 *) ps_ent_ctxt->pu1_top_nnz_cbcr[ps_ent_ctxt->i4_mb_x];
        *nnz = 0;

        /* residual */
        error_status = isvce_encode_residue(ps_ent_ctxt, P16x16, 0);

        bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

        ps_ent_ctxt->u4_header_bits[is_inter] += bitstream_end_offset - bitstream_start_offset;

        return error_status;
    }

    /* remaining mb header info */
    cbp = ps_mb_hdr->u1_cbp;
    mb_qp_delta =
        ((WORD16) ps_mb_hdr->u1_mb_qp) - ((WORD16) ps_ent_ctxt->ps_mb_qp_ctxt->u1_cur_mb_qp);

    /* mb skip run */
    PUT_BITS_UEV(ps_bitstream, *ps_ent_ctxt->pi4_mb_skip_run, error_status, "mb skip run");

    /* reset skip counter */
    *ps_ent_ctxt->pi4_mb_skip_run = 0;

    if(ps_ent_ctxt->u1_spatial_layer_id && ps_svc_slice_header->i1_adaptive_base_mode_flag)
    {
        /* write base_mode_flag */
        PUT_BITS(ps_bitstream, ps_mb_hdr->u1_base_mode_flag, 1, error_status, "base_mode_flag");
    }
    else
    {
        ps_mb_hdr->u1_base_mode_flag = 0;
    }

    if(!ps_mb_hdr->u1_base_mode_flag)
    {
        /* is intra ? */
        if(mb_type == I16x16)
        {
            UWORD32 u4_cbp_l, u4_cbp_c;

            is_inter = 0;

            u4_cbp_c = (cbp >> 4);
            u4_cbp_l = (cbp & 0xF);
            luma_intra_mode = (mb_tpm >> 4) & 3;
            chroma_intra_mode = (mb_tpm >> 6);

            mb_type_stream = luma_intra_mode + 1 + (u4_cbp_c << 2) + (u4_cbp_l == 15) * 12;

            mb_type_stream += 5;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, mb_type_stream, error_status, "mb type");

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");
            pu1_byte += sizeof(isvce_mb_hdr_i16x16_t);
        }
        else if(mb_type == I4x4)
        {
            isvce_mb_hdr_i4x4_t *ps_mb_hdr_i4x4 =
                (isvce_mb_hdr_i4x4_t *) ps_ent_ctxt->pv_mb_header_data;

            /* mb sub blk modes */
            WORD32 intra_pred_mode_flag, rem_intra_mode;
            WORD32 byte;

            is_inter = 0;

            chroma_intra_mode = (mb_tpm >> 6);
            cbptable = 0;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, 5, error_status, "mb type");

            for(i = 0; i < 16; i += 2)
            {
                /* sub blk idx 1 */
                byte = ps_mb_hdr_i4x4->au1_sub_blk_modes[i >> 1];

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }

                /* sub blk idx 2 */
                byte >>= 4;

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }
            }

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");

            pu1_byte += sizeof(isvce_mb_hdr_i4x4_t);
        }
        else if(mb_type == I8x8)
        {
            isvce_mb_hdr_i8x8_t *ps_mb_hdr_i8x8 =
                (isvce_mb_hdr_i8x8_t *) ps_ent_ctxt->pv_mb_header_data;

            /* transform 8x8 flag */
            UWORD32 u4_transform_size_8x8_flag = ps_ent_ctxt->i1_transform_8x8_mode_flag;

            /* mb sub blk modes */
            WORD32 intra_pred_mode_flag, rem_intra_mode;
            WORD32 byte;

            is_inter = 0;

            chroma_intra_mode = (mb_tpm >> 6);
            cbptable = 0;

            ASSERT(0);

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, 5, error_status, "mb type");

            /* u4_transform_size_8x8_flag */
            PUT_BITS(ps_bitstream, u4_transform_size_8x8_flag, 1, error_status,
                     "u4_transform_size_8x8_flag");

            /* write sub block modes */
            for(i = 0; i < 4; i++)
            {
                /* sub blk idx 1 */
                byte = ps_mb_hdr_i8x8->au1_sub_blk_modes[i >> 1];

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }

                /* sub blk idx 2 */
                byte >>= 4;

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }
            }

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");

            pu1_byte += sizeof(isvce_mb_hdr_i8x8_t);
        }
        else
        {
            isvce_mb_hdr_p16x16_t *ps_mb_hdr_p16x16 =
                (isvce_mb_hdr_p16x16_t *) ps_ent_ctxt->pv_mb_header_data;

            /* inter macro block partition cnt */
            const UWORD8 au1_part_cnt[] = {1, 2, 2, 4};

            /* mv ptr */
            WORD16 *pi2_mv_ptr = (WORD16 *) ps_mb_hdr_p16x16->ai2_mvd;

            /* number of partitions for the current mb */
            UWORD32 u4_part_cnt = au1_part_cnt[mb_type - 3];

            is_inter = 1;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, mb_type - 3, error_status, "mb type");

            for(i = 0; i < (WORD32) u4_part_cnt; i++)
            {
                if(ps_ent_ctxt->u1_spatial_layer_id &&
                   ps_svc_slice_header->i1_adaptive_motion_prediction_flag)
                {
                    PUT_BITS(ps_bitstream, ps_mb_hdr_p16x16->u1_mvp_idx, 1, error_status,
                             "motion_prediction_flag_l0");
                }
            }

            for(i = 0; i < (WORD32) u4_part_cnt; i++)
            {
                PUT_BITS_SEV(ps_bitstream, pi2_mv_ptr[i], error_status, "mv x");
                PUT_BITS_SEV(ps_bitstream, pi2_mv_ptr[i + 1], error_status, "mv y");
            }

            pu1_byte += sizeof(isvce_mb_hdr_p16x16_t);
        }
    }
    else
    {
        pu1_byte += sizeof(isvce_mb_hdr_base_mode_t);
    }

    if(ps_ent_ctxt->u1_spatial_layer_id &&
       ps_svc_slice_header->i1_adaptive_residual_prediction_flag &&
       !ps_ent_ctxt
            ->ps_svc_nalu_ext_base[1 + (ps_ent_ctxt->i4_cur_slice_idx % SVC_MAX_SLICE_HDR_CNT)]
            .u1_idr_flag &&
       (ps_mb_hdr->u1_base_mode_flag || !u1_is_intra_mb))
    {
        PUT_BITS(ps_bitstream, ps_mb_hdr->u1_residual_prediction_flag, 1, error_status,
                 "residual_prediction_flag");
    }

    /* coded_block_pattern */
    if(ps_mb_hdr->u1_base_mode_flag || (mb_type != I16x16))
    {
        PUT_BITS_UEV(ps_bitstream, gu1_cbp_map_tables[cbp][cbptable], error_status,
                     "coded_block_pattern");
    }

    if((cbp > 0) || (mb_type == I16x16))
    {
        /* mb_qp_delta */
        PUT_BITS_SEV(ps_bitstream, mb_qp_delta, error_status, "mb_qp_delta");
        ps_ent_ctxt->ps_mb_qp_ctxt->u1_cur_mb_qp = ps_mb_hdr->u1_mb_qp;
    }

    /* Ending bitstream offset for header in bits */
    bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

    ps_ent_ctxt->u4_header_bits[is_inter] += bitstream_end_offset - bitstream_start_offset;

    /* start bitstream offset for residue in bits */
    bitstream_start_offset = bitstream_end_offset;

    /* residual */
    error_status = isvce_encode_residue(ps_ent_ctxt, mb_type, cbp);

    /* Ending bitstream offset for residue in bits */
    bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

    ps_ent_ctxt->u4_residue_bits[is_inter] += bitstream_end_offset - bitstream_start_offset;

    /* store the index of the next mb syntax layer */
    ps_ent_ctxt->pv_mb_header_data = pu1_byte;

    return error_status;
}

/**
*******************************************************************************
*
* @brief
*  This function generates CAVLC coded bit stream for B slices
*
* @description
*  The mb syntax layer for inter slices constitutes luma mb mode, luma sub modes
*  (if present), mb qp delta, coded block pattern, chroma mb mode and
*  luma/chroma residue. These syntax elements are written as directed by table
*  7.3.5 of h264 specification
*
* @param[in] ps_ent_ctxt
*  pointer to entropy context
*
* @returns error code
*
* @remarks none
*
*******************************************************************************
*/
IH264E_ERROR_T isvce_write_bslice_mb_cavlc(isvce_entropy_ctxt_t *ps_ent_ctxt)
{
    /* mb header info */
    /*
     * mb_tpm : mb type plus mode
     * mb_type : luma mb type and chroma mb type are packed
     * cbp : coded block pattern
     * mb_qp_delta : mb qp delta
     * chroma_intra_mode : chroma intra mode
     * luma_intra_mode : luma intra mode
     * ps_pu :  Pointer to the array of structures having motion vectors, size
     * and position of sub partitions
     */
    WORD32 mb_tpm, mb_type, cbp, chroma_intra_mode, luma_intra_mode;
    WORD8 mb_qp_delta;
    WORD32 i, j;
    WORD32 mb_type_stream;
    WORD32 bitstream_start_offset, bitstream_end_offset;
    UWORD8 u1_is_intra_mb;

    bitstrm_t *ps_bitstream = ps_ent_ctxt->ps_bitstrm;
    isvce_mb_hdr_common_t *ps_mb_hdr = (isvce_mb_hdr_common_t *) ps_ent_ctxt->pv_mb_header_data;
    svc_slice_header_t *ps_svc_slice_header =
        ps_ent_ctxt->ps_svc_slice_hdr_base +
        (ps_ent_ctxt->i4_cur_slice_idx % SVC_MAX_SLICE_HDR_CNT);

    IH264E_ERROR_T error_status = IH264E_SUCCESS;

    UWORD8 *pu1_byte = ps_ent_ctxt->pv_mb_header_data;
    WORD32 cbptable = 1;
    WORD32 is_inter = 0;

    /* Starting bitstream offset for header in bits */
    bitstream_start_offset = isvce_get_num_bits(ps_bitstream);

    /********************************************************************/
    /*                    BEGIN HEADER GENERATION                       */
    /********************************************************************/

    mb_tpm = ps_mb_hdr->u1_mb_type_mode;

    /* mb type */
    mb_type = mb_tpm & 0xF;
    u1_is_intra_mb = (mb_type == I16x16) || (mb_type == I8x8) || (mb_type == I4x4);

    /* check for skip */
    if(mb_type == BSKIP)
    {
        UWORD32 *nnz;

        is_inter = 1;

        /* increment skip counter */
        (*ps_ent_ctxt->pi4_mb_skip_run)++;

        /* store the index of the next mb syntax layer */
        pu1_byte += sizeof(isvce_mb_hdr_bskip_t);
        ps_ent_ctxt->pv_mb_header_data = pu1_byte;

        /* set nnz to zero */
        ps_ent_ctxt->u4_left_nnz_luma = 0;
        nnz = (UWORD32 *) ps_ent_ctxt->pu1_top_nnz_luma[ps_ent_ctxt->i4_mb_x];
        *nnz = 0;
        ps_ent_ctxt->u4_left_nnz_cbcr = 0;
        nnz = (UWORD32 *) ps_ent_ctxt->pu1_top_nnz_cbcr[ps_ent_ctxt->i4_mb_x];
        *nnz = 0;

        /* residual */
        error_status = isvce_encode_residue(ps_ent_ctxt, B16x16, 0);

        bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

        ps_ent_ctxt->u4_header_bits[is_inter] += bitstream_end_offset - bitstream_start_offset;

        return error_status;
    }

    /* remaining mb header info */
    cbp = ps_mb_hdr->u1_cbp;
    mb_qp_delta =
        ((WORD16) ps_mb_hdr->u1_mb_qp) - ((WORD16) ps_ent_ctxt->ps_mb_qp_ctxt->u1_cur_mb_qp);

    /* mb skip run */
    PUT_BITS_UEV(ps_bitstream, *ps_ent_ctxt->pi4_mb_skip_run, error_status, "mb skip run");

    /* reset skip counter */
    *ps_ent_ctxt->pi4_mb_skip_run = 0;

    if(ps_ent_ctxt->u1_spatial_layer_id && ps_svc_slice_header->i1_adaptive_base_mode_flag)
    {
        /* write base_mode_flag */
        PUT_BITS(ps_bitstream, ps_mb_hdr->u1_base_mode_flag, 1, error_status, "base_mode_flag");
    }
    else
    {
        ps_mb_hdr->u1_base_mode_flag = 0;
    }

    if(!ps_mb_hdr->u1_base_mode_flag)
    {
        /* is intra ? */
        if(mb_type == I16x16)
        {
            UWORD32 u4_cbp_l, u4_cbp_c;

            is_inter = 0;

            u4_cbp_c = (cbp >> 4);
            u4_cbp_l = (cbp & 0xF);
            luma_intra_mode = (mb_tpm >> 4) & 3;
            chroma_intra_mode = (mb_tpm >> 6);

            mb_type_stream = luma_intra_mode + 1 + (u4_cbp_c << 2) + (u4_cbp_l == 15) * 12;

            mb_type_stream += 23;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, mb_type_stream, error_status, "mb type");

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");
            pu1_byte += sizeof(isvce_mb_hdr_i16x16_t);
        }
        else if(mb_type == I4x4)
        {
            isvce_mb_hdr_i4x4_t *ps_mb_hdr_i4x4 =
                (isvce_mb_hdr_i4x4_t *) ps_ent_ctxt->pv_mb_header_data;

            /* mb sub blk modes */
            WORD32 intra_pred_mode_flag, rem_intra_mode;
            WORD32 byte;

            is_inter = 0;

            chroma_intra_mode = (mb_tpm >> 6);
            cbptable = 0;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, 23, error_status, "mb type");

            for(i = 0; i < 16; i += 2)
            {
                /* sub blk idx 1 */
                byte = ps_mb_hdr_i4x4->au1_sub_blk_modes[i >> 1];

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }

                /* sub blk idx 2 */
                byte >>= 4;

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }
            }

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");
            pu1_byte += sizeof(isvce_mb_hdr_i4x4_t);
        }
        else if(mb_type == I8x8)
        {
            isvce_mb_hdr_i8x8_t *ps_mb_hdr_i8x8 =
                (isvce_mb_hdr_i8x8_t *) ps_ent_ctxt->pv_mb_header_data;

            /* transform 8x8 flag */
            UWORD32 u4_transform_size_8x8_flag = ps_ent_ctxt->i1_transform_8x8_mode_flag;

            /* mb sub blk modes */
            WORD32 intra_pred_mode_flag, rem_intra_mode;
            WORD32 byte;

            is_inter = 0;

            chroma_intra_mode = (mb_tpm >> 6);
            cbptable = 0;

            ASSERT(0);

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, 23, error_status, "mb type");

            /* u4_transform_size_8x8_flag */
            PUT_BITS(ps_bitstream, u4_transform_size_8x8_flag, 1, error_status,
                     "u4_transform_size_8x8_flag");

            /* write sub block modes */
            for(i = 0; i < 4; i++)
            {
                /* sub blk idx 1 */
                byte = ps_mb_hdr_i8x8->au1_sub_blk_modes[i >> 1];

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }

                /* sub blk idx 2 */
                byte >>= 4;

                intra_pred_mode_flag = byte & 0x1;

                /* prev_intra4x4_pred_mode_flag */
                PUT_BITS(ps_bitstream, intra_pred_mode_flag, 1, error_status,
                         "prev_intra4x4_pred_mode_flag");

                /* rem_intra4x4_pred_mode */
                if(!intra_pred_mode_flag)
                {
                    rem_intra_mode = (byte & 0xF) >> 1;
                    PUT_BITS(ps_bitstream, rem_intra_mode, 3, error_status,
                             "rem_intra4x4_pred_mode");
                }
            }

            /* intra_chroma_pred_mode */
            PUT_BITS_UEV(ps_bitstream, chroma_intra_mode, error_status, "intra_chroma_pred_mode");
            pu1_byte += sizeof(isvce_mb_hdr_i8x8_t);
        }
        else if(mb_type == BDIRECT)
        {
            is_inter = 1;
            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, B_DIRECT_16x16, error_status, "mb type");
            pu1_byte += sizeof(isvce_mb_hdr_bdirect_t);
        }
        else
        {
            isvce_mb_hdr_b16x16_t *ps_mb_hdr_b16x16 =
                (isvce_mb_hdr_b16x16_t *) ps_ent_ctxt->pv_mb_header_data;

            /* inter macro block partition cnt for 16x16 16x8 8x16 8x8 */
            const UWORD8 au1_part_cnt[] = {1, 2, 2, 4};

            /* number of partitions for the current mb */
            UWORD32 u4_part_cnt = au1_part_cnt[mb_type - B16x16];

            /* Get the pred modes */
            WORD32 i4_mb_part_pred_mode = (mb_tpm >> 4);

            ASSERT(mb_type == B16x16);

            is_inter = 1;

            mb_type_stream = mb_type - B16x16 + B_L0_16x16 + i4_mb_part_pred_mode;

            /* write mb type */
            PUT_BITS_UEV(ps_bitstream, mb_type_stream, error_status, "mb type");

            for(i = 0; i < (WORD32) u4_part_cnt; i++)
            {
                for(j = 0; j < NUM_PRED_DIRS; j++)
                {
                    PRED_MODE_T e_pred_mode = (PRED_MODE_T) j;
                    PRED_MODE_T e_cmpl_pred_mode = (e_pred_mode == L0) ? L1 : L0;

                    if(((PRED_MODE_T) i4_mb_part_pred_mode) != e_pred_mode)
                    {
                        if(ps_svc_slice_header->i1_adaptive_motion_prediction_flag &&
                           ps_ent_ctxt->u1_spatial_layer_id)
                        {
                            PUT_BITS(ps_bitstream, ps_mb_hdr_b16x16->au1_mvp_idx[e_cmpl_pred_mode],
                                     1, error_status, "motion_prediction_flag_l0");
                        }
                    }
                }
            }

            for(i = 0; i < (WORD32) u4_part_cnt; i++)
            {
                if(i4_mb_part_pred_mode != L1)
                {
                    PUT_BITS_SEV(ps_bitstream, ps_mb_hdr_b16x16->ai2_mvd[0][0], error_status,
                                 "mv l0 x");
                    PUT_BITS_SEV(ps_bitstream, ps_mb_hdr_b16x16->ai2_mvd[0][1], error_status,
                                 "mv l0 y");
                }
                if(i4_mb_part_pred_mode != L0)
                {
                    PUT_BITS_SEV(ps_bitstream, ps_mb_hdr_b16x16->ai2_mvd[1][0], error_status,
                                 "mv l1 x");
                    PUT_BITS_SEV(ps_bitstream, ps_mb_hdr_b16x16->ai2_mvd[1][1], error_status,
                                 "mv l1 y");
                }
            }

            pu1_byte += sizeof(isvce_mb_hdr_b16x16_t);
        }
    }

    if(ps_svc_slice_header->i1_adaptive_residual_prediction_flag &&
       ps_ent_ctxt->u1_spatial_layer_id && (ps_mb_hdr->u1_base_mode_flag || !u1_is_intra_mb))
    {
        PUT_BITS(ps_bitstream, ps_mb_hdr->u1_residual_prediction_flag, 1, error_status,
                 "residual_prediction_flag");
    }

    /* coded_block_pattern */
    if(ps_mb_hdr->u1_base_mode_flag || mb_type != I16x16)
    {
        PUT_BITS_UEV(ps_bitstream, gu1_cbp_map_tables[cbp][cbptable], error_status,
                     "coded_block_pattern");
    }

    if((cbp > 0) || (mb_type == I16x16))
    {
        /* mb_qp_delta */
        PUT_BITS_SEV(ps_bitstream, mb_qp_delta, error_status, "mb_qp_delta");
        ps_ent_ctxt->ps_mb_qp_ctxt->u1_cur_mb_qp = ps_mb_hdr->u1_mb_qp;
    }

    /* Ending bitstream offset for header in bits */
    bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

    ps_ent_ctxt->u4_header_bits[is_inter] += bitstream_end_offset - bitstream_start_offset;

    /* start bitstream offset for residue in bits */
    bitstream_start_offset = bitstream_end_offset;

    /* residual */
    error_status = isvce_encode_residue(ps_ent_ctxt, mb_type, cbp);

    /* Ending bitstream offset for residue in bits */
    bitstream_end_offset = isvce_get_num_bits(ps_bitstream);

    ps_ent_ctxt->u4_residue_bits[is_inter] += bitstream_end_offset - bitstream_start_offset;

    /* store the index of the next mb syntax layer */
    ps_ent_ctxt->pv_mb_header_data = pu1_byte;

    return error_status;
}

#if ENABLE_RE_ENC_AS_SKIP
/**
******************************************************************************
*
*  @brief re-encode frame as all skip MBs
*
*  @par   Description
*  The frame is encoded as all skip MBs to comply with VBV restrictions
*
*  @param[in]    ps_entropy
*  pointer to entropy context (handle)
*
*  @return      success or failure error code
*
******************************************************************************
*/
IH264E_ERROR_T isvce_reencode_as_skip_frame_cavlc(isvce_entropy_ctxt_t *ps_entropy)
{
    WORD32 i4_mb_skip_run;

    bitstrm_t *ps_bitstrm = ps_entropy->ps_bitstrm;
    bitstrm_t *ps_bitstrm_after_slice_hdr = ps_entropy->ps_bitstrm_after_slice_hdr;

    ps_bitstrm->i4_bits_left_in_cw = ps_bitstrm_after_slice_hdr->i4_bits_left_in_cw;
    ps_bitstrm->u4_cur_word = ps_bitstrm_after_slice_hdr->u4_cur_word;
    ps_bitstrm->u4_strm_buf_offset = ps_bitstrm_after_slice_hdr->u4_strm_buf_offset;
    ps_bitstrm->i4_zero_bytes_run = ps_bitstrm_after_slice_hdr->i4_zero_bytes_run;

    /* mb skip run */
    i4_mb_skip_run = ps_entropy->i4_wd_mbs * ps_entropy->i4_ht_mbs;
    PUT_BITS_UEV(ps_bitstrm, i4_mb_skip_run, ps_entropy->i4_error_code, "mb skip run");

    /* put rbsp trailing bits */
    ps_entropy->i4_error_code = ih264e_put_rbsp_trailing_bits(ps_bitstrm);

    return ps_entropy->i4_error_code;
}
#endif