/******************************************************************************

 *

 * 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

 *  ih264_resi_trans_quant.c

 *

 * @brief

 *  Contains function definitions single stage  forward transform for H.264

 *  It will calculate the residue, do the cf and then do quantization

 *

 * @author

 *  Ittiam

 *

 * @par List of Functions:

 *  - ih264_resi_trans_quant_4x4()

 *  - ih264_resi_trans_quant_chroma_4x4

 *  - ih264_hadamard_quant_4x4

 *  - ih264_hadamard_quant_2x2_uv

 *  - ih264_resi_trans_quant_8x8

 *

 * @remarks

 *******************************************************************************

 */

/* System include files */

#include <stdbool.h>

#include <stddef.h>

/* User include files */

#include "ih264_typedefs.h"

#include "ih264_defs.h"

#include "ih264_size_defs.h"

#include "ih264_macros.h"

#include "ih264_trans_macros.h"

#include "ih264_trans_data.h"

#include "ih264_structs.h"

#include "isvc_trans_quant_itrans_iquant.h"

static FORCEINLINE WORD16 isvc_subtract_upsampled_res(WORD16 i2_residue, WORD16 i2_upsampled_res)

{

    return (CLIP3(-((WORD16) UINT8_MAX), ((WORD16) UINT8_MAX), i2_residue - i2_upsampled_res));

}

/**

 *******************************************************************************

 *

 * @brief

 *   This function performs forward transform and quantization on a 4*4 block

 *

 * @par Description:

 *   The function accepts source buffer and estimation buffer. From these, it

 *   computes the residue. This is residue is then transformed and quantized.

 *   The transform and quantization are in placed computed. They use the residue

 *   buffer for this.

 *

 * @param[in] pu1_src

 *   Pointer to source sub-block

 *

 * @param[in] pu1_pred

 *   Pointer to prediction sub-block

 *

 * @param[in] pi2_out

 *   Pointer to residual sub-block

 *

 * @param[in] i4_src_stride

 *   Source stride

 *

 * @param[in] i4_pred_stride

 *   Prediction stride

 *

 * @param[in] dst_strd

 *   Destination stride

 *

 * @param[in] u4_qbits

 *    QP_BITS_h264_4x4 + floor(QP/6)

 *

 * @param[in] pu2_threshold_matrix

 *   Pointer to Forward Quant Threshold Matrix

 *

 * @param[in] pu2_scale_matrix

 *   Pointer to Forward Quant Scale Matrix

 *

 * @param[in] u4_round_factor

 *   Quantization Round factor

 *

 * @param[out] pu1_nnz

 *   Total non-zero coefficients in the current sub-block

 *

 * @returns

 *

 * @remarks

 *   None

 *

 *******************************************************************************

 */

void isvc_resi_trans_quant_4x4(buffer_container_t *ps_src, buffer_container_t *ps_pred,

                               buffer_container_t *ps_out, buffer_container_t *ps_upsampled_res,

                               resi_trans_quant_constants_t *ps_quant_constants, UWORD8 *pu1_nnz,

                               WORD16 *pi2_dc_out, UWORD8 u1_use_upsampled_res)

{

    UWORD32 i;

    WORD32 x0, x1, x2, x3, x4, x5, x6, x7;

    WORD32 i4_value;

    UWORD8 *pu1_src = ps_src->pv_data;

    UWORD8 *pu1_pred = ps_pred->pv_data;

    WORD16 *pi2_out = ps_out->pv_data;

    WORD16 *pi2_upsampled_res = ps_upsampled_res ? ps_upsampled_res->pv_data : NULL;

    WORD32 i4_src_stride = ps_src->i4_data_stride;

    WORD32 i4_pred_stride = ps_pred->i4_data_stride;

    WORD32 i4_upsampled_res_stride = ps_upsampled_res ? ps_upsampled_res->i4_data_stride : 0;

    WORD16 *pi2_out_tmp = pi2_out;

    UWORD32 u4_nonzero_coeff = 0;

    const UWORD16 *pu2_scale_matrix = ps_quant_constants->pu2_scale_matrix;

    const UWORD16 *pu2_threshold_matrix = ps_quant_constants->pu2_threshold_matrix;

    UWORD32 u4_qbits = ps_quant_constants->u4_qbits;

    UWORD32 u4_round_factor = ps_quant_constants->u4_round_factor;

    for(i = 0; i < SUB_BLK_WIDTH_4x4; i++)

    {

        /* computing prediction error (residue) */

        x4 = pu1_src[0] - pu1_pred[0];

        x5 = pu1_src[1] - pu1_pred[1];

        x6 = pu1_src[2] - pu1_pred[2];

        x7 = pu1_src[3] - pu1_pred[3];

        if(u1_use_upsampled_res)

        {

            x4 = isvc_subtract_upsampled_res(x4, pi2_upsampled_res[0]);

            x5 = isvc_subtract_upsampled_res(x5, pi2_upsampled_res[1]);

            x6 = isvc_subtract_upsampled_res(x6, pi2_upsampled_res[2]);

            x7 = isvc_subtract_upsampled_res(x7, pi2_upsampled_res[3]);

        }

        /* Horizontal transform */

        x0 = x4 + x7;

        x1 = x5 + x6;

        x2 = x5 - x6;

        x3 = x4 - x7;

        pi2_out_tmp[0] = x0 + x1;

        pi2_out_tmp[1] = (x3 << 1) + x2;

        pi2_out_tmp[2] = x0 - x1;

        pi2_out_tmp[3] = x3 - (x2 << 1);

        /* pointing to next row; */

        pu1_src += i4_src_stride;

        pu1_pred += i4_pred_stride;

        pi2_out_tmp += 4;

        pi2_upsampled_res += i4_upsampled_res_stride;

    }

    pi2_out_tmp = pi2_out;

    for(i = 0; i < SUB_BLK_WIDTH_4x4; i++)

    {

        /* Vertical transform and quantization */

        x4 = pi2_out_tmp[0];

        x5 = pi2_out_tmp[4];

        x6 = pi2_out_tmp[8];

        x7 = pi2_out_tmp[12];

        x0 = x4 + x7;

        x1 = x5 + x6;

        x2 = x5 - x6;

        x3 = x4 - x7;

        /* quantization is done in place */

        i4_value = x0 + x1;

        if(i == 0)

        {

            (*pi2_dc_out) = i4_value;

        }

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[0] = i4_value;

        i4_value = (x3 << 1) + x2;

        FWD_QUANT(i4_value, pu2_threshold_matrix[4], pu2_scale_matrix[4], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[4] = i4_value;

        i4_value = x0 - x1;

        FWD_QUANT(i4_value, pu2_threshold_matrix[8], pu2_scale_matrix[8], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[8] = i4_value;

        i4_value = x3 - (x2 << 1);

        FWD_QUANT(i4_value, pu2_threshold_matrix[12], pu2_scale_matrix[12], u4_round_factor,

                  u4_qbits, u4_nonzero_coeff);

        pi2_out_tmp[12] = i4_value;

        pi2_out_tmp++;

        pu2_scale_matrix++;

        pu2_threshold_matrix++;

    }

    /* Return total nonzero coefficients in the current sub block */

    *pu1_nnz = u4_nonzero_coeff;

}

/**

 *******************************************************************************

 *

 * @brief

 *   This function performs forward transform and quantization on a 4*4 chroma

 *block with interleaved values

 *

 * @par Description:

 *   The function accepts source buffer and estimation buffer. From these, it

 *   computes the residue. This is residue is then transformed and quantized.

 *   The transform and quantization are in placed computed. They use the residue

 *   buffer for this.

 *

 * @param[in] pu1_src

 *   Pointer to source sub-block

 *

 * @param[in] pu1_pred

 *   Pointer to prediction sub-block

 *

 * @param[in] pi2_out

 *   Pointer to residual sub-block

 *

 * @param[in] i4_src_stride

 *   Source stride

 *

 * @param[in] i4_pred_stride

 *   Prediction stride

 *

 * @param[in] dst_strd

 *   Destination stride

 *

 * @param[in] u4_qbits

 *    QP_BITS_h264_4x4 + floor(QP/6)

 *

 * @param[in] pu2_threshold_matrix

 *   Pointer to Forward Quant Threshold Matrix

 *

 * @param[in] pu2_scale_matrix

 *   Pointer to Forward Quant Scale Matrix

 *

 * @param[in] u4_round_factor

 *   Quantization Round factor

 *

 * @param[out] pu1_nnz

 *   Total non-zero coefficients in the current sub-block

 *

 * @returns

 *

 * @remarks

 *   None

 *

 *******************************************************************************

 */

void isvc_resi_trans_quant_chroma_4x4(buffer_container_t *ps_src, buffer_container_t *ps_pred,

                                      buffer_container_t *ps_out,

                                      buffer_container_t *ps_upsampled_res,

                                      resi_trans_quant_constants_t *ps_quant_constants,

                                      UWORD8 *pu1_nnz, WORD16 *pi2_dc_out,

                                      UWORD8 u1_use_upsampled_res)

{

    UWORD32 i;

    WORD32 x0, x1, x2, x3, x4, x5, x6, x7;

    WORD32 i4_value;

    UWORD8 *pu1_src = ps_src->pv_data;

    UWORD8 *pu1_pred = ps_pred->pv_data;

    WORD16 *pi2_out = ps_out->pv_data;

    WORD16 *pi2_upsampled_res = ps_upsampled_res ? ps_upsampled_res->pv_data : NULL;

    WORD32 i4_src_stride = ps_src->i4_data_stride;

    WORD32 i4_pred_stride = ps_pred->i4_data_stride;

    WORD32 i4_upsampled_res_stride = ps_upsampled_res ? ps_upsampled_res->i4_data_stride : 0;

    WORD16 *pi2_out_tmp = pi2_out;

    UWORD32 u4_nonzero_coeff = 0;

    const UWORD16 *pu2_scale_matrix = ps_quant_constants->pu2_scale_matrix;

    const UWORD16 *pu2_threshold_matrix = ps_quant_constants->pu2_threshold_matrix;

    UWORD32 u4_qbits = ps_quant_constants->u4_qbits;

    UWORD32 u4_round_factor = ps_quant_constants->u4_round_factor;

    for(i = 0; i < SUB_BLK_WIDTH_4x4; i++)

    {

        /* computing prediction error (residue) */

        x4 = pu1_src[0] - pu1_pred[0];

        x5 = pu1_src[2] - pu1_pred[2];

        x6 = pu1_src[4] - pu1_pred[4];

        x7 = pu1_src[6] - pu1_pred[6];

        if(u1_use_upsampled_res)

        {

            x4 = isvc_subtract_upsampled_res(x4, pi2_upsampled_res[0]);

            x5 = isvc_subtract_upsampled_res(x5, pi2_upsampled_res[1]);

            x6 = isvc_subtract_upsampled_res(x6, pi2_upsampled_res[2]);

            x7 = isvc_subtract_upsampled_res(x7, pi2_upsampled_res[3]);

        }

        /* Horizontal transform */

        x0 = x4 + x7;

        x1 = x5 + x6;

        x2 = x5 - x6;

        x3 = x4 - x7;

        pi2_out_tmp[0] = x0 + x1;

        pi2_out_tmp[1] = (x3 << 1) + x2;

        pi2_out_tmp[2] = x0 - x1;

        pi2_out_tmp[3] = x3 - (x2 << 1);

        /* pointing to next row; */

        pu1_src += i4_src_stride;

        pu1_pred += i4_pred_stride;

        pi2_out_tmp += 4;

        pi2_upsampled_res += i4_upsampled_res_stride;

    }

    pi2_out_tmp = pi2_out;

    for(i = 0; i < SUB_BLK_WIDTH_4x4; i++)

    {

        /* Vertical transform and quantization */

        x4 = pi2_out_tmp[0];

        x5 = pi2_out_tmp[4];

        x6 = pi2_out_tmp[8];

        x7 = pi2_out_tmp[12];

        x0 = x4 + x7;

        x1 = x5 + x6;

        x2 = x5 - x6;

        x3 = x4 - x7;

        /* quantization is done in place */

        i4_value = x0 + x1;

        if(i == 0)

        {

            *pi2_dc_out = i4_value;

        }

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[0] = i4_value;

        i4_value = (x3 << 1) + x2;

        FWD_QUANT(i4_value, pu2_threshold_matrix[4], pu2_scale_matrix[4], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[4] = i4_value;

        i4_value = x0 - x1;

        FWD_QUANT(i4_value, pu2_threshold_matrix[8], pu2_scale_matrix[8], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[8] = i4_value;

        i4_value = x3 - (x2 << 1);

        FWD_QUANT(i4_value, pu2_threshold_matrix[12], pu2_scale_matrix[12], u4_round_factor,

                  u4_qbits, u4_nonzero_coeff);

        pi2_out_tmp[12] = i4_value;

        pi2_out_tmp++;

        pu2_scale_matrix++;

        pu2_threshold_matrix++;

    }

    /* Return total nonzero coefficients in the current sub block */

    *pu1_nnz = u4_nonzero_coeff;

}

/**

 *******************************************************************************

 *

 * @brief

 *   This function performs forward hadamard transform and quantization on a 4*4

 *block

 *

 * @par Description:

 *   The function accepts source buffer and estimation buffer. From these, it

 *   computes the residue. This is residue is then transformed and quantized.

 *   The transform and quantization are in placed computed. They use the residue

 *   buffer for this.

 *

 * @param[in] pu1_src

 *   Pointer to source sub-block

 *

 * @param[in] pu1_pred

 *   Pointer to prediction sub-block

 *

 * @param[in] pi2_out

 *   Pointer to residual sub-block

 *

 * @param[in] i4_src_stride

 *   Source stride

 *

 * @param[in] i4_pred_stride

 *   Prediction stride

 *

 * @param[in] dst_strd

 *   Destination stride

 *

 * @param[in] u4_qbits

 *    QP_BITS_h264_4x4 + floor(QP/6)

 *

 * @param[in] pu2_threshold_matrix

 *   Pointer to Forward Quant Threshold Matrix

 *

 * @param[in] pu2_scale_matrix

 *   Pointer to Forward Quant Scale Matrix

 *

 * @param[in] u4_round_factor

 *   Quantization Round factor

 *

 * @param[out] pu1_nnz

 *   Total non-zero coefficients in the current sub-block

 *

 * @returns

 *

 * @remarks

 *   None

 *

 */

void isvc_hadamard_quant_4x4(WORD16 *pi2_src, WORD16 *pi2_dst,

                             resi_trans_quant_constants_t *ps_quant_constants, UWORD8 *pu1_nnz)

{

    WORD32 i;

    WORD32 x0, x1, x2, x3, x4, x5, x6, x7, i4_value;

    const UWORD16 *pu2_scale_matrix = ps_quant_constants->pu2_scale_matrix;

    const UWORD16 *pu2_threshold_matrix = ps_quant_constants->pu2_threshold_matrix;

    UWORD32 u4_qbits = ps_quant_constants->u4_qbits;

    UWORD32 u4_round_factor = ps_quant_constants->u4_round_factor;

    *pu1_nnz = 0;

    for(i = 0; i < SUB_BLK_WIDTH_4x4; i++)

    {

        x4 = pi2_src[0];

        x5 = pi2_src[1];

        x6 = pi2_src[2];

        x7 = pi2_src[3];

        x0 = x4 + x7;

        x1 = x5 + x6;

        x2 = x5 - x6;

        x3 = x4 - x7;

        pi2_dst[0] = x0 + x1;

        pi2_dst[1] = x3 + x2;

        pi2_dst[2] = x0 - x1;

        pi2_dst[3] = x3 - x2;

        pi2_src += 4;

        pi2_dst += 4;

    }

    /* Vertical transform and quantization */

    pi2_dst -= SUB_BLK_WIDTH_4x4 << 2;

    for(i = 0; i < SUB_BLK_WIDTH_4x4; i++)

    {

        x4 = pi2_dst[0];

        x5 = pi2_dst[4];

        x6 = pi2_dst[8];

        x7 = pi2_dst[12];

        x0 = x4 + x7;

        x1 = x5 + x6;

        x2 = x5 - x6;

        x3 = x4 - x7;

        i4_value = (x0 + x1) >> 1;

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[0]);

        pi2_dst[0] = i4_value;

        i4_value = (x3 + x2) >> 1;

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[0]);

        pi2_dst[4] = i4_value;

        i4_value = (x0 - x1) >> 1;

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[0]);

        pi2_dst[8] = i4_value;

        i4_value = (x3 - x2) >> 1;

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[0]);

        pi2_dst[12] = i4_value;

        pi2_dst++;

    }

}

/**

 *******************************************************************************

 *

 * @brief

 *   This function performs forward hadamard transform and quantization on a 2*2

 *block for both U and V planes

 *

 * @par Description:

 *   The function accepts source buffer and estimation buffer. From these, it

 *   computes the residue. This is residue is then transformed and quantized.

 *   The transform and quantization are in placed computed. They use the residue

 *   buffer for this.

 *

 * @param[in] pu1_src

 *   Pointer to source sub-block

 *

 * @param[in] pu1_pred

 *   Pointer to prediction sub-block

 *

 * @param[in] pi2_out

 *   Pointer to residual sub-block

 *

 * @param[in] i4_src_stride

 *   Source stride

 *

 * @param[in] i4_pred_stride

 *   Prediction stride

 *

 * @param[in] dst_strd

 *   Destination stride

 *

 * @param[in] u4_qbits

 *    QP_BITS_h264_4x4 + floor(QP/6)

 *

 * @param[in] pu2_threshold_matrix

 *   Pointer to Forward Quant Threshold Matrix

 *

 * @param[in] pu2_scale_matrix

 *   Pointer to Forward Quant Scale Matrix

 *

 * @param[in] u4_round_factor

 *   Quantization Round factor

 *

 * @param[out] pu1_nnz

 *   Total non-zero coefficients in the current sub-block

 *

 * @returns

 *

 * @remarks

 *   NNZ for dc is populated at 0 and 5th position of pu1_nnz

 *

 */

void isvc_hadamard_quant_2x2_uv(WORD16 *pi2_src, WORD16 *pi2_dst,

                                resi_trans_quant_constants_t *ps_quant_constants, UWORD8 *pu1_nnz)

{

    WORD32 x0, x1, x2, x3, x4, x5, x6, x7;

    WORD32 i4_value, plane;

    const UWORD16 *pu2_scale_matrix = ps_quant_constants->pu2_scale_matrix;

    const UWORD16 *pu2_threshold_matrix = ps_quant_constants->pu2_threshold_matrix;

    UWORD32 u4_qbits = ps_quant_constants->u4_qbits;

    UWORD32 u4_round_factor = ps_quant_constants->u4_round_factor;

    for(plane = 0; plane < 2; plane++)

    {

        pu1_nnz[plane] = 0;

        /* Horizontal transform */

        x4 = pi2_src[0];

        x5 = pi2_src[1];

        x6 = pi2_src[2];

        x7 = pi2_src[3];

        x0 = x4 + x5;

        x1 = x4 - x5;

        x2 = x6 + x7;

        x3 = x6 - x7;

        /* Vertical transform and quantization */

        i4_value = (x0 + x2);

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[plane]);

        pi2_dst[0] = i4_value;

        i4_value = (x0 - x2);

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[plane]);

        pi2_dst[2] = i4_value;

        i4_value = (x1 - x3);

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[plane]);

        pi2_dst[3] = i4_value;

        i4_value = (x1 + x3);

        FWD_QUANT(i4_value, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  pu1_nnz[plane]);

        pi2_dst[1] = i4_value;

        pi2_dst += 4;

        pi2_src += 4;

    }

}

/*

 *******************************************************************************

 *

 * @brief

 *  This function performs Single stage forward transform CF8 and quantization

 *on 8*8 blocks for h.264

 *

 * @par Description:

 *  Performs single stage 8x8 forward transform CF8 after calculating the

 *residue The result is then quantized

 *

 * @param[in] pu1_src

 *  Input 8x8 pixels

 *

 * @param[in] pu1_pred

 *  Input 8x8 pixels

 *

 * @param[in] pi1_out

 * Output 8x8 pixels

 *

 * @param[in] u4_thresh

 *  Threshold under which the coeffs are not quantized

 *

 *  @param[in] u4_qp_div

 *  QP/6

 *

 *  @param[in] u4_qp_rem

 *  QP%6

 *

 * @param[in] u2_src_stride

 *  Source stride

 *

 * @param[in] i4_pred_stride

 * stride for prediciton buffer

 *

 *  @param[in] dst_strd

 *  stride for destination buffer

 *

 *  @param[in] pu4_quant_mat

 *  Pointer to the 4x4 quantization matrix

 *

 * @returns  Void

 *

 *

 *******************************************************************************

 */

void isvc_resi_trans_quant_8x8(buffer_container_t *ps_src, buffer_container_t *ps_pred,

                               buffer_container_t *ps_out, buffer_container_t *ps_upsampled_res,

                               resi_trans_quant_constants_t *ps_quant_constants, UWORD8 *pu1_nnz,

                               WORD16 *pi2_dc_out, UWORD8 u1_use_upsampled_res)

{

    UWORD32 i;

    WORD32 a0, a1, a2, a3, a4, a5, a6, a7;

    WORD32 r0, r1, r2, r3, r4, r5, r6, r7;

    UWORD8 *pu1_src = ps_src->pv_data;

    UWORD8 *pu1_pred = ps_pred->pv_data;

    WORD16 *pi2_out = ps_out->pv_data;

    WORD16 *pi2_upsampled_res = ps_upsampled_res ? ps_upsampled_res->pv_data : NULL;

    WORD32 i4_src_stride = ps_src->i4_data_stride;

    WORD32 i4_pred_stride = ps_pred->i4_data_stride;

    WORD32 i4_upsampled_res_stride = ps_upsampled_res ? ps_upsampled_res->i4_data_stride : 0;

    WORD16 *pi2_out_tmp = pi2_out;

    UWORD32 u4_nonzero_coeff = 0;

    const UWORD16 *pu2_scale_matrix = ps_quant_constants->pu2_scale_matrix;

    const UWORD16 *pu2_threshold_matrix = ps_quant_constants->pu2_threshold_matrix;

    UWORD32 u4_qbits = ps_quant_constants->u4_qbits;

    UWORD32 u4_round_factor = ps_quant_constants->u4_round_factor;

    UNUSED(pi2_dc_out);

    /*Horizontal transform */

    /* we are going to use the a's and r's in a twisted way since */

    /*i dont want to declare more variables */

    for(i = 0; i < SUB_BLK_WIDTH_8x8; ++i)

    {

        r0 = pu1_src[0];

        r0 -= pu1_pred[0];

        r1 = pu1_src[1];

        r1 -= pu1_pred[1];

        r2 = pu1_src[2];

        r2 -= pu1_pred[2];

        r3 = pu1_src[3];

        r3 -= pu1_pred[3];

        r4 = pu1_src[4];

        r4 -= pu1_pred[4];

        r5 = pu1_src[5];

        r5 -= pu1_pred[5];

        r6 = pu1_src[6];

        r6 -= pu1_pred[6];

        r7 = pu1_src[7];

        r7 -= pu1_pred[7];

        if(u1_use_upsampled_res)

        {

            r0 = isvc_subtract_upsampled_res(r0, pi2_upsampled_res[0]);

            r1 = isvc_subtract_upsampled_res(r1, pi2_upsampled_res[1]);

            r2 = isvc_subtract_upsampled_res(r2, pi2_upsampled_res[2]);

            r3 = isvc_subtract_upsampled_res(r3, pi2_upsampled_res[3]);

            r4 = isvc_subtract_upsampled_res(r4, pi2_upsampled_res[4]);

            r5 = isvc_subtract_upsampled_res(r5, pi2_upsampled_res[5]);

            r6 = isvc_subtract_upsampled_res(r6, pi2_upsampled_res[6]);

            r7 = isvc_subtract_upsampled_res(r7, pi2_upsampled_res[7]);

        }

        a0 = r0 + r7;

        a1 = r1 + r6;

        a2 = r2 + r5;

        a3 = r3 + r4;

        a4 = a0 + a3;

        a5 = a1 + a2;

        a6 = a0 - a3;

        a7 = a1 - a2;

        pi2_out_tmp[0] = a4 + a5;

        pi2_out_tmp[2] = a6 + (a7 >> 1);

        pi2_out_tmp[4] = a4 - a5;

        pi2_out_tmp[6] = (a6 >> 1) - a7;

        a0 = r0 - r7;

        a1 = r1 - r6;

        a2 = r2 - r5;

        a3 = r3 - r4;

        a4 = a1 + a2 + ((a0 >> 1) + a0);

        a5 = a0 - a3 - ((a2 >> 1) + a2);

        a6 = a0 + a3 - ((a1 >> 1) + a1);

        a7 = a1 - a2 + ((a3 >> 1) + a3);

        pi2_out_tmp[1] = a4 + (a7 >> 2);

        pi2_out_tmp[3] = a5 + (a6 >> 2);

        pi2_out_tmp[5] = a6 - (a5 >> 2);

        pi2_out_tmp[7] = (a4 >> 2) - a7;

        pu1_src += i4_src_stride;

        pu1_pred += i4_pred_stride;

        pi2_out_tmp += 8;

        pi2_upsampled_res += i4_upsampled_res_stride;

    }

    /*vertical transform and quant */

    pi2_out_tmp = pi2_out;

    for(i = 0; i < SUB_BLK_WIDTH_8x8; ++i)

    {

        r0 = pi2_out_tmp[0];

        r1 = pi2_out_tmp[8];

        r2 = pi2_out_tmp[16];

        r3 = pi2_out_tmp[24];

        r4 = pi2_out_tmp[32];

        r5 = pi2_out_tmp[40];

        r6 = pi2_out_tmp[48];

        r7 = pi2_out_tmp[56];

        a0 = r0 + r7;

        a1 = r1 + r6;

        a2 = r2 + r5;

        a3 = r3 + r4;

        a4 = a0 + a3;

        a5 = a1 + a2;

        a6 = a0 - a3;

        a7 = a1 - a2;

        a0 = r0 - r7;

        a1 = r1 - r6;

        a2 = r2 - r5;

        a3 = r3 - r4;

        r0 = a4 + a5;

        r2 = a6 + (a7 >> 1);

        r4 = a4 - a5;

        r6 = (a6 >> 1) - a7;

        a4 = a1 + a2 + ((a0 >> 1) + a0);

        a5 = a0 - a3 - ((a2 >> 1) + a2);

        a6 = a0 + a3 - ((a1 >> 1) + a1);

        a7 = a1 - a2 + ((a3 >> 1) + a3);

        r1 = a4 + (a7 >> 2);

        r3 = a5 + (a6 >> 2);

        r5 = a6 - (a5 >> 2);

        r7 = (a4 >> 2) - a7;

        FWD_QUANT(r0, pu2_threshold_matrix[0], pu2_scale_matrix[0], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[0] = r0;

        FWD_QUANT(r1, pu2_threshold_matrix[8], pu2_scale_matrix[8], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[8] = r1;

        FWD_QUANT(r2, pu2_threshold_matrix[16], pu2_scale_matrix[16], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[16] = r2;

        FWD_QUANT(r3, pu2_threshold_matrix[24], pu2_scale_matrix[24], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[24] = r3;

        FWD_QUANT(r4, pu2_threshold_matrix[32], pu2_scale_matrix[32], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[32] = r4;

        FWD_QUANT(r5, pu2_threshold_matrix[40], pu2_scale_matrix[40], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[40] = r5;

        FWD_QUANT(r6, pu2_threshold_matrix[48], pu2_scale_matrix[48], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[48] = r6;

        FWD_QUANT(r7, pu2_threshold_matrix[56], pu2_scale_matrix[56], u4_round_factor, u4_qbits,

                  u4_nonzero_coeff);

        pi2_out_tmp[56] = r7;

        pi2_out_tmp++;

        pu2_scale_matrix++;

        pu2_threshold_matrix++;

    }

    /* Return total nonzero coefficients in the current sub block */

    *pu1_nnz = u4_nonzero_coeff;

}