mcomp.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 "mcomp.h"
#include "vpx_mem/vpx_mem.h"
#include "vpx_ports/config.h"
#include <stdio.h>
#include <limits.h>
#include <math.h>
#include "vp8/common/findnearmv.h"

#ifdef ENTROPY_STATS
static int mv_ref_ct [31] [4] [2];
static int mv_mode_cts [4] [2];
#endif

#if CONFIG_HIGH_PRECISION_MV
int vp8_mv_bit_cost(int_mv *mv, int_mv *ref, int *mvcost[2], int Weight, int ishp)
{
    // MV costing is based on the distribution of vectors in the previous frame and as such will tend to
    // over state the cost of vectors. In addition coding a new vector can have a knock on effect on the
    // cost of subsequent vectors and the quality of prediction from NEAR and NEAREST for subsequent blocks.
    // The "Weight" parameter allows, to a limited extent, for some account to be taken of these factors.
    return ((mvcost[0][(mv->as_mv.row - ref->as_mv.row) >> (ishp==0)] + mvcost[1][(mv->as_mv.col - ref->as_mv.col) >> (ishp==0)]) * Weight) >> 7;
}
#else
int vp8_mv_bit_cost(int_mv *mv, int_mv *ref, int *mvcost[2], int Weight)
{
    // MV costing is based on the distribution of vectors in the previous frame and as such will tend to
    // over state the cost of vectors. In addition coding a new vector can have a knock on effect on the
    // cost of subsequent vectors and the quality of prediction from NEAR and NEAREST for subsequent blocks.
    // The "Weight" parameter allows, to a limited extent, for some account to be taken of these factors.
    return ((mvcost[0][(mv->as_mv.row - ref->as_mv.row) >> 1] + mvcost[1][(mv->as_mv.col - ref->as_mv.col) >> 1]) * Weight) >> 7;
}
#endif

#if CONFIG_HIGH_PRECISION_MV
static int mv_err_cost(int_mv *mv, int_mv *ref, int *mvcost[2], int error_per_bit, int ishp)
{
    return ((mvcost[0][(mv->as_mv.row - ref->as_mv.row) >> (ishp==0)] +
        mvcost[1][(mv->as_mv.col - ref->as_mv.col) >> (ishp==0)])
        * error_per_bit + 128) >> 8;
}
#else
static int mv_err_cost(int_mv *mv, int_mv *ref, int *mvcost[2], int error_per_bit)
{
    return ((mvcost[0][(mv->as_mv.row - ref->as_mv.row) >> 1] +
        mvcost[1][(mv->as_mv.col - ref->as_mv.col) >> 1])
        * error_per_bit + 128) >> 8;
}
#endif


static int mvsad_err_cost(int_mv *mv, int_mv *ref, int *mvsadcost[2], int error_per_bit)
{
    /* Calculate sad error cost on full pixel basis. */
    return ((mvsadcost[0][(mv->as_mv.row - ref->as_mv.row)] +
        mvsadcost[1][(mv->as_mv.col - ref->as_mv.col)])
        * error_per_bit + 128) >> 8;
}