/*
 *  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_config.h"
#include "vp8/encoder/variance.h"
#include "vp8/common/pragmas.h"
#include "vpx_ports/mem.h"

#if CONFIG_SIXTEENTH_SUBPEL_UV
#define HALFNDX 8
#else
#define HALFNDX 4
#endif

extern unsigned int vp8_get16x16var_sse2
(
    const unsigned char *src_ptr,
    int source_stride,
    const unsigned char *ref_ptr,
    int recon_stride,
    unsigned int *SSE,
    int *Sum
);
extern void vp8_half_horiz_vert_variance16x_h_sse2
(
    const unsigned char *ref_ptr,
    int ref_pixels_per_line,
    const unsigned char *src_ptr,
    int src_pixels_per_line,
    unsigned int Height,
    int *sum,
    unsigned int *sumsquared
);
extern void vp8_half_horiz_variance16x_h_sse2
(
    const unsigned char *ref_ptr,
    int ref_pixels_per_line,
    const unsigned char *src_ptr,
    int src_pixels_per_line,
    unsigned int Height,
    int *sum,
    unsigned int *sumsquared
);
extern void vp8_half_vert_variance16x_h_sse2
(
    const unsigned char *ref_ptr,
    int ref_pixels_per_line,
    const unsigned char *src_ptr,
    int src_pixels_per_line,
    unsigned int Height,
    int *sum,
    unsigned int *sumsquared
);
extern void vp8_filter_block2d_bil_var_ssse3
(
    const unsigned char *ref_ptr,
    int ref_pixels_per_line,
    const unsigned char *src_ptr,
    int src_pixels_per_line,
    unsigned int Height,
    int  xoffset,
    int  yoffset,
    int *sum,
    unsigned int *sumsquared
);

unsigned int vp8_sub_pixel_variance16x16_ssse3
(
    const unsigned char  *src_ptr,
    int  src_pixels_per_line,
    int  xoffset,
    int  yoffset,
    const unsigned char *dst_ptr,
    int dst_pixels_per_line,
    unsigned int *sse
)
{
    int xsum0;
    unsigned int xxsum0;

    // note we could avoid these if statements if the calling function
    // just called the appropriate functions inside.
    if (xoffset == HALFNDX && yoffset == 0)
    {
        vp8_half_horiz_variance16x_h_sse2(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 16,
            &xsum0, &xxsum0);
    }
    else if (xoffset == 0 && yoffset == HALFNDX)
    {
        vp8_half_vert_variance16x_h_sse2(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 16,
            &xsum0, &xxsum0);
    }
    else if (xoffset == HALFNDX && yoffset == HALFNDX)
    {
        vp8_half_horiz_vert_variance16x_h_sse2(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 16,
            &xsum0, &xxsum0);
    }
    else
    {
        vp8_filter_block2d_bil_var_ssse3(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 16,
            xoffset, yoffset,
            &xsum0, &xxsum0);
    }

    *sse = xxsum0;
    return (xxsum0 - ((xsum0 * xsum0) >> 8));
}

unsigned int vp8_sub_pixel_variance16x8_ssse3
(
    const unsigned char  *src_ptr,
    int  src_pixels_per_line,
    int  xoffset,
    int  yoffset,
    const unsigned char *dst_ptr,
    int dst_pixels_per_line,
    unsigned int *sse

)
{
    int xsum0;
    unsigned int xxsum0;

    if (xoffset == HALFNDX && yoffset == 0)
    {
        vp8_half_horiz_variance16x_h_sse2(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 8,
            &xsum0, &xxsum0);
    }
    else if (xoffset == 0 && yoffset == HALFNDX)
    {
        vp8_half_vert_variance16x_h_sse2(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 8,
            &xsum0, &xxsum0);
    }
    else if (xoffset == HALFNDX && yoffset == HALFNDX)
    {
        vp8_half_horiz_vert_variance16x_h_sse2(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 8,
            &xsum0, &xxsum0);
    }
    else
    {
        vp8_filter_block2d_bil_var_ssse3(
            src_ptr, src_pixels_per_line,
            dst_ptr, dst_pixels_per_line, 8,
            xoffset, yoffset,
            &xsum0, &xxsum0);
    }

    *sse = xxsum0;
    return (xxsum0 - ((xsum0 * xsum0) >> 7));
}