xref: /external/libvpx/vp8/common/reconintra4x4.c

/*
 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */


#include "vpx_ports/config.h"
#include "recon.h"
#include "vpx_mem/vpx_mem.h"
#include "reconintra.h"

void vp8_predict_intra4x4(BLOCKD *x,
                          int b_mode,
                          unsigned char *predictor)
{
    int i, r, c;

    unsigned char *Above = *(x->base_dst) + x->dst - x->dst_stride;
    unsigned char Left[4];
    unsigned char top_left = Above[-1];

    Left[0] = (*(x->base_dst))[x->dst - 1];
    Left[1] = (*(x->base_dst))[x->dst - 1 + x->dst_stride];
    Left[2] = (*(x->base_dst))[x->dst - 1 + 2 * x->dst_stride];
    Left[3] = (*(x->base_dst))[x->dst - 1 + 3 * x->dst_stride];

    switch (b_mode)
    {
    case B_DC_PRED:
    {
        int expected_dc = 0;

        for (i = 0; i < 4; i++)
        {
            expected_dc += Above[i];
            expected_dc += Left[i];
        }

        expected_dc = (expected_dc + 4) >> 3;

        for (r = 0; r < 4; r++)
        {
            for (c = 0; c < 4; c++)
            {
                predictor[c] = expected_dc;
            }

            predictor += 16;
        }
    }
    break;
    case B_TM_PRED:
    {
        /* prediction similar to true_motion prediction */
        for (r = 0; r < 4; r++)
        {
            for (c = 0; c < 4; c++)
            {
                int pred = Above[c] - top_left + Left[r];

                if (pred < 0)
                    pred = 0;

                if (pred > 255)
                    pred = 255;

                predictor[c] = pred;
            }

            predictor += 16;
        }
    }
    break;

    case B_VE_PRED:
    {

        unsigned int ap[4];
        ap[0] = (top_left  + 2 * Above[0] + Above[1] + 2) >> 2;
        ap[1] = (Above[0] + 2 * Above[1] + Above[2] + 2) >> 2;
        ap[2] = (Above[1] + 2 * Above[2] + Above[3] + 2) >> 2;
        ap[3] = (Above[2] + 2 * Above[3] + Above[4] + 2) >> 2;

        for (r = 0; r < 4; r++)
        {
            for (c = 0; c < 4; c++)
            {

                predictor[c] = ap[c];
            }

            predictor += 16;
        }

    }
    break;


    case B_HE_PRED:
    {

        unsigned int lp[4];
        lp[0] = (top_left + 2 * Left[0] + Left[1] + 2) >> 2;
        lp[1] = (Left[0] + 2 * Left[1] + Left[2] + 2) >> 2;
        lp[2] = (Left[1] + 2 * Left[2] + Left[3] + 2) >> 2;
        lp[3] = (Left[2] + 2 * Left[3] + Left[3] + 2) >> 2;

        for (r = 0; r < 4; r++)
        {
            for (c = 0; c < 4; c++)
            {
                predictor[c] = lp[r];
            }

            predictor += 16;
        }
    }
    break;
    case B_LD_PRED:
    {
        unsigned char *ptr = Above;
        predictor[0 * 16 + 0] = (ptr[0] + ptr[1] * 2 + ptr[2] + 2) >> 2;
        predictor[0 * 16 + 1] =
            predictor[1 * 16 + 0] = (ptr[1] + ptr[2] * 2 + ptr[3] + 2) >> 2;
        predictor[0 * 16 + 2] =
            predictor[1 * 16 + 1] =
                predictor[2 * 16 + 0] = (ptr[2] + ptr[3] * 2 + ptr[4] + 2) >> 2;
        predictor[0 * 16 + 3] =
            predictor[1 * 16 + 2] =
                predictor[2 * 16 + 1] =
                    predictor[3 * 16 + 0] = (ptr[3] + ptr[4] * 2 + ptr[5] + 2) >> 2;
        predictor[1 * 16 + 3] =
            predictor[2 * 16 + 2] =
                predictor[3 * 16 + 1] = (ptr[4] + ptr[5] * 2 + ptr[6] + 2) >> 2;
        predictor[2 * 16 + 3] =
            predictor[3 * 16 + 2] = (ptr[5] + ptr[6] * 2 + ptr[7] + 2) >> 2;
        predictor[3 * 16 + 3] = (ptr[6] + ptr[7] * 2 + ptr[7] + 2) >> 2;

    }
    break;
    case B_RD_PRED:
    {

        unsigned char pp[9];

        pp[0] = Left[3];
        pp[1] = Left[2];
        pp[2] = Left[1];
        pp[3] = Left[0];
        pp[4] = top_left;
        pp[5] = Above[0];
        pp[6] = Above[1];
        pp[7] = Above[2];
        pp[8] = Above[3];

        predictor[3 * 16 + 0] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
        predictor[3 * 16 + 1] =
            predictor[2 * 16 + 0] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
        predictor[3 * 16 + 2] =
            predictor[2 * 16 + 1] =
                predictor[1 * 16 + 0] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
        predictor[3 * 16 + 3] =
            predictor[2 * 16 + 2] =
                predictor[1 * 16 + 1] =
                    predictor[0 * 16 + 0] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
        predictor[2 * 16 + 3] =
            predictor[1 * 16 + 2] =
                predictor[0 * 16 + 1] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
        predictor[1 * 16 + 3] =
            predictor[0 * 16 + 2] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
        predictor[0 * 16 + 3] = (pp[6] + pp[7] * 2 + pp[8] + 2) >> 2;

    }
    break;
    case B_VR_PRED:
    {

        unsigned char pp[9];

        pp[0] = Left[3];
        pp[1] = Left[2];
        pp[2] = Left[1];
        pp[3] = Left[0];
        pp[4] = top_left;
        pp[5] = Above[0];
        pp[6] = Above[1];
        pp[7] = Above[2];
        pp[8] = Above[3];


        predictor[3 * 16 + 0] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
        predictor[2 * 16 + 0] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
        predictor[3 * 16 + 1] =
            predictor[1 * 16 + 0] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
        predictor[2 * 16 + 1] =
            predictor[0 * 16 + 0] = (pp[4] + pp[5] + 1) >> 1;
        predictor[3 * 16 + 2] =
            predictor[1 * 16 + 1] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
        predictor[2 * 16 + 2] =
            predictor[0 * 16 + 1] = (pp[5] + pp[6] + 1) >> 1;
        predictor[3 * 16 + 3] =
            predictor[1 * 16 + 2] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
        predictor[2 * 16 + 3] =
            predictor[0 * 16 + 2] = (pp[6] + pp[7] + 1) >> 1;
        predictor[1 * 16 + 3] = (pp[6] + pp[7] * 2 + pp[8] + 2) >> 2;
        predictor[0 * 16 + 3] = (pp[7] + pp[8] + 1) >> 1;

    }
    break;
    case B_VL_PRED:
    {

        unsigned char *pp = Above;

        predictor[0 * 16 + 0] = (pp[0] + pp[1] + 1) >> 1;
        predictor[1 * 16 + 0] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
        predictor[2 * 16 + 0] =
            predictor[0 * 16 + 1] = (pp[1] + pp[2] + 1) >> 1;
        predictor[1 * 16 + 1] =
            predictor[3 * 16 + 0] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
        predictor[2 * 16 + 1] =
            predictor[0 * 16 + 2] = (pp[2] + pp[3] + 1) >> 1;
        predictor[3 * 16 + 1] =
            predictor[1 * 16 + 2] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
        predictor[0 * 16 + 3] =
            predictor[2 * 16 + 2] = (pp[3] + pp[4] + 1) >> 1;
        predictor[1 * 16 + 3] =
            predictor[3 * 16 + 2] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
        predictor[2 * 16 + 3] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
        predictor[3 * 16 + 3] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
    }
    break;

    case B_HD_PRED:
    {
        unsigned char pp[9];
        pp[0] = Left[3];
        pp[1] = Left[2];
        pp[2] = Left[1];
        pp[3] = Left[0];
        pp[4] = top_left;
        pp[5] = Above[0];
        pp[6] = Above[1];
        pp[7] = Above[2];
        pp[8] = Above[3];


        predictor[3 * 16 + 0] = (pp[0] + pp[1] + 1) >> 1;
        predictor[3 * 16 + 1] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
        predictor[2 * 16 + 0] =
            predictor[3 * 16 + 2] = (pp[1] + pp[2] + 1) >> 1;
        predictor[2 * 16 + 1] =
            predictor[3 * 16 + 3] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
        predictor[2 * 16 + 2] =
            predictor[1 * 16 + 0] = (pp[2] + pp[3] + 1) >> 1;
        predictor[2 * 16 + 3] =
            predictor[1 * 16 + 1] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
        predictor[1 * 16 + 2] =
            predictor[0 * 16 + 0] = (pp[3] + pp[4] + 1) >> 1;
        predictor[1 * 16 + 3] =
            predictor[0 * 16 + 1] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
        predictor[0 * 16 + 2] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
        predictor[0 * 16 + 3] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
    }
    break;


    case B_HU_PRED:
    {
        unsigned char *pp = Left;
        predictor[0 * 16 + 0] = (pp[0] + pp[1] + 1) >> 1;
        predictor[0 * 16 + 1] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
        predictor[0 * 16 + 2] =
            predictor[1 * 16 + 0] = (pp[1] + pp[2] + 1) >> 1;
        predictor[0 * 16 + 3] =
            predictor[1 * 16 + 1] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
        predictor[1 * 16 + 2] =
            predictor[2 * 16 + 0] = (pp[2] + pp[3] + 1) >> 1;
        predictor[1 * 16 + 3] =
            predictor[2 * 16 + 1] = (pp[2] + pp[3] * 2 + pp[3] + 2) >> 2;
        predictor[2 * 16 + 2] =
            predictor[2 * 16 + 3] =
                predictor[3 * 16 + 0] =
                    predictor[3 * 16 + 1] =
                        predictor[3 * 16 + 2] =
                            predictor[3 * 16 + 3] = pp[3];
    }
    break;


    }
}
/* copy 4 bytes from the above right down so that the 4x4 prediction modes using pixels above and
 * to the right prediction have filled in pixels to use.
 */
void vp8_intra_prediction_down_copy(MACROBLOCKD *x)
{
    unsigned char *above_right = *(x->block[0].base_dst) + x->block[0].dst - x->block[0].dst_stride + 16;

    unsigned int *src_ptr = (unsigned int *)above_right;
    unsigned int *dst_ptr0 = (unsigned int *)(above_right + 4 * x->block[0].dst_stride);
    unsigned int *dst_ptr1 = (unsigned int *)(above_right + 8 * x->block[0].dst_stride);
    unsigned int *dst_ptr2 = (unsigned int *)(above_right + 12 * x->block[0].dst_stride);

    *dst_ptr0 = *src_ptr;
    *dst_ptr1 = *src_ptr;
    *dst_ptr2 = *src_ptr;
}