/*M///////////////////////////////////////////////////////////////////////////////////////
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//
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//  If you do not agree to this license, do not download, install,
//  copy or use the software.
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//
//                           License Agreement
//                For Open Source Computer Vision Library
//
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// are permitted provided that the following conditions are met:
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//M*/

#include "precomp.hpp"
#include "opencl_kernels_imgproc.hpp"

namespace cv
{

template<typename T, int shift> struct FixPtCast
{
    typedef int type1;
    typedef T rtype;
    rtype operator ()(type1 arg) const { return (T)((arg + (1 << (shift-1))) >> shift); }
};

template<typename T, int shift> struct FltCast
{
    typedef T type1;
    typedef T rtype;
    rtype operator ()(type1 arg) const { return arg*(T)(1./(1 << shift)); }
};

template<typename T1, typename T2> struct NoVec
{
    int operator()(T1**, T2*, int, int) const { return 0; }
};

#if CV_SSE2

struct PyrDownVec_32s8u
{
    int operator()(int** src, uchar* dst, int, int width) const
    {
        if( !checkHardwareSupport(CV_CPU_SSE2) )
            return 0;

        int x = 0;
        const int *row0 = src[0], *row1 = src[1], *row2 = src[2], *row3 = src[3], *row4 = src[4];
        __m128i delta = _mm_set1_epi16(128);

        for( ; x <= width - 16; x += 16 )
        {
            __m128i r0, r1, r2, r3, r4, t0, t1;
            r0 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row0 + x)),
                                 _mm_load_si128((const __m128i*)(row0 + x + 4)));
            r1 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row1 + x)),
                                 _mm_load_si128((const __m128i*)(row1 + x + 4)));
            r2 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row2 + x)),
                                 _mm_load_si128((const __m128i*)(row2 + x + 4)));
            r3 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row3 + x)),
                                 _mm_load_si128((const __m128i*)(row3 + x + 4)));
            r4 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row4 + x)),
                                 _mm_load_si128((const __m128i*)(row4 + x + 4)));
            r0 = _mm_add_epi16(r0, r4);
            r1 = _mm_add_epi16(_mm_add_epi16(r1, r3), r2);
            r0 = _mm_add_epi16(r0, _mm_add_epi16(r2, r2));
            t0 = _mm_add_epi16(r0, _mm_slli_epi16(r1, 2));
            r0 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row0 + x + 8)),
                                 _mm_load_si128((const __m128i*)(row0 + x + 12)));
            r1 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row1 + x + 8)),
                                 _mm_load_si128((const __m128i*)(row1 + x + 12)));
            r2 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row2 + x + 8)),
                                 _mm_load_si128((const __m128i*)(row2 + x + 12)));
            r3 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row3 + x + 8)),
                                 _mm_load_si128((const __m128i*)(row3 + x + 12)));
            r4 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row4 + x + 8)),
                                 _mm_load_si128((const __m128i*)(row4 + x + 12)));
            r0 = _mm_add_epi16(r0, r4);
            r1 = _mm_add_epi16(_mm_add_epi16(r1, r3), r2);
            r0 = _mm_add_epi16(r0, _mm_add_epi16(r2, r2));
            t1 = _mm_add_epi16(r0, _mm_slli_epi16(r1, 2));
            t0 = _mm_srli_epi16(_mm_add_epi16(t0, delta), 8);
            t1 = _mm_srli_epi16(_mm_add_epi16(t1, delta), 8);
            _mm_storeu_si128((__m128i*)(dst + x), _mm_packus_epi16(t0, t1));
        }

        for( ; x <= width - 4; x += 4 )
        {
            __m128i r0, r1, r2, r3, r4, z = _mm_setzero_si128();
            r0 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row0 + x)), z);
            r1 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row1 + x)), z);
            r2 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row2 + x)), z);
            r3 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row3 + x)), z);
            r4 = _mm_packs_epi32(_mm_load_si128((const __m128i*)(row4 + x)), z);
            r0 = _mm_add_epi16(r0, r4);
            r1 = _mm_add_epi16(_mm_add_epi16(r1, r3), r2);
            r0 = _mm_add_epi16(r0, _mm_add_epi16(r2, r2));
            r0 = _mm_add_epi16(r0, _mm_slli_epi16(r1, 2));
            r0 = _mm_srli_epi16(_mm_add_epi16(r0, delta), 8);
            *(int*)(dst + x) = _mm_cvtsi128_si32(_mm_packus_epi16(r0, r0));
        }

        return x;
    }
};

struct PyrDownVec_32f
{
    int operator()(float** src, float* dst, int, int width) const
    {
        if( !checkHardwareSupport(CV_CPU_SSE) )
            return 0;

        int x = 0;
        const float *row0 = src[0], *row1 = src[1], *row2 = src[2], *row3 = src[3], *row4 = src[4];
        __m128 _4 = _mm_set1_ps(4.f), _scale = _mm_set1_ps(1.f/256);
        for( ; x <= width - 8; x += 8 )
        {
            __m128 r0, r1, r2, r3, r4, t0, t1;
            r0 = _mm_load_ps(row0 + x);
            r1 = _mm_load_ps(row1 + x);
            r2 = _mm_load_ps(row2 + x);
            r3 = _mm_load_ps(row3 + x);
            r4 = _mm_load_ps(row4 + x);
            r0 = _mm_add_ps(r0, r4);
            r1 = _mm_add_ps(_mm_add_ps(r1, r3), r2);
            r0 = _mm_add_ps(r0, _mm_add_ps(r2, r2));
            t0 = _mm_add_ps(r0, _mm_mul_ps(r1, _4));

            r0 = _mm_load_ps(row0 + x + 4);
            r1 = _mm_load_ps(row1 + x + 4);
            r2 = _mm_load_ps(row2 + x + 4);
            r3 = _mm_load_ps(row3 + x + 4);
            r4 = _mm_load_ps(row4 + x + 4);
            r0 = _mm_add_ps(r0, r4);
            r1 = _mm_add_ps(_mm_add_ps(r1, r3), r2);
            r0 = _mm_add_ps(r0, _mm_add_ps(r2, r2));
            t1 = _mm_add_ps(r0, _mm_mul_ps(r1, _4));

            t0 = _mm_mul_ps(t0, _scale);
            t1 = _mm_mul_ps(t1, _scale);

            _mm_storeu_ps(dst + x, t0);
            _mm_storeu_ps(dst + x + 4, t1);
        }

        return x;
    }
};

typedef NoVec<int, ushort> PyrDownVec_32s16u;
typedef NoVec<int, short> PyrDownVec_32s16s;

typedef NoVec<float, float> PyrUpVec_32f;

#elif CV_NEON

struct PyrDownVec_32s8u
{
    int operator()(int** src, uchar* dst, int, int width) const
    {
        int x = 0;
        const unsigned int *row0 = (unsigned int*)src[0], *row1 = (unsigned int*)src[1],
                           *row2 = (unsigned int*)src[2], *row3 = (unsigned int*)src[3],
                           *row4 = (unsigned int*)src[4];
        uint16x8_t v_delta = vdupq_n_u16(128);

        for( ; x <= width - 16; x += 16 )
        {
            uint16x8_t v_r0 = vcombine_u16(vqmovn_u32(vld1q_u32(row0 + x)), vqmovn_u32(vld1q_u32(row0 + x + 4)));
            uint16x8_t v_r1 = vcombine_u16(vqmovn_u32(vld1q_u32(row1 + x)), vqmovn_u32(vld1q_u32(row1 + x + 4)));
            uint16x8_t v_r2 = vcombine_u16(vqmovn_u32(vld1q_u32(row2 + x)), vqmovn_u32(vld1q_u32(row2 + x + 4)));
            uint16x8_t v_r3 = vcombine_u16(vqmovn_u32(vld1q_u32(row3 + x)), vqmovn_u32(vld1q_u32(row3 + x + 4)));
            uint16x8_t v_r4 = vcombine_u16(vqmovn_u32(vld1q_u32(row4 + x)), vqmovn_u32(vld1q_u32(row4 + x + 4)));

            v_r0 = vqaddq_u16(vqaddq_u16(v_r0, v_r4), vqaddq_u16(v_r2, v_r2));
            v_r1 = vqaddq_u16(vqaddq_u16(v_r1, v_r2), v_r3);
            uint16x8_t v_dst0 = vqaddq_u16(v_r0, vshlq_n_u16(v_r1, 2));

            v_r0 = vcombine_u16(vqmovn_u32(vld1q_u32(row0 + x + 8)), vqmovn_u32(vld1q_u32(row0 + x + 12)));
            v_r1 = vcombine_u16(vqmovn_u32(vld1q_u32(row1 + x + 8)), vqmovn_u32(vld1q_u32(row1 + x + 12)));
            v_r2 = vcombine_u16(vqmovn_u32(vld1q_u32(row2 + x + 8)), vqmovn_u32(vld1q_u32(row2 + x + 12)));
            v_r3 = vcombine_u16(vqmovn_u32(vld1q_u32(row3 + x + 8)), vqmovn_u32(vld1q_u32(row3 + x + 12)));
            v_r4 = vcombine_u16(vqmovn_u32(vld1q_u32(row4 + x + 8)), vqmovn_u32(vld1q_u32(row4 + x + 12)));

            v_r0 = vqaddq_u16(vqaddq_u16(v_r0, v_r4), vqaddq_u16(v_r2, v_r2));
            v_r1 = vqaddq_u16(vqaddq_u16(v_r1, v_r2), v_r3);
            uint16x8_t v_dst1 = vqaddq_u16(v_r0, vshlq_n_u16(v_r1, 2));

            vst1q_u8(dst + x, vcombine_u8(vqmovn_u16(vshrq_n_u16(vaddq_u16(v_dst0, v_delta), 8)),
                                          vqmovn_u16(vshrq_n_u16(vaddq_u16(v_dst1, v_delta), 8))));
        }

        return x;
    }
};

struct PyrDownVec_32s16u
{
    int operator()(int** src, ushort* dst, int, int width) const
    {
        int x = 0;
        const int *row0 = src[0], *row1 = src[1], *row2 = src[2], *row3 = src[3], *row4 = src[4];
        int32x4_t v_delta = vdupq_n_s32(128);

        for( ; x <= width - 8; x += 8 )
        {
            int32x4_t v_r00 = vld1q_s32(row0 + x), v_r01 = vld1q_s32(row0 + x + 4);
            int32x4_t v_r10 = vld1q_s32(row1 + x), v_r11 = vld1q_s32(row1 + x + 4);
            int32x4_t v_r20 = vld1q_s32(row2 + x), v_r21 = vld1q_s32(row2 + x + 4);
            int32x4_t v_r30 = vld1q_s32(row3 + x), v_r31 = vld1q_s32(row3 + x + 4);
            int32x4_t v_r40 = vld1q_s32(row4 + x), v_r41 = vld1q_s32(row4 + x + 4);

            v_r00 = vaddq_s32(vqaddq_s32(v_r00, v_r40), vqaddq_s32(v_r20, v_r20));
            v_r10 = vaddq_s32(vqaddq_s32(v_r10, v_r20), v_r30);
            int32x4_t v_dst0 = vshrq_n_s32(vaddq_s32(vqaddq_s32(v_r00, vshlq_n_s32(v_r10, 2)), v_delta), 8);

            v_r01 = vaddq_s32(vqaddq_s32(v_r01, v_r41), vqaddq_s32(v_r21, v_r21));
            v_r11 = vaddq_s32(vqaddq_s32(v_r11, v_r21), v_r31);
            int32x4_t v_dst1 = vshrq_n_s32(vaddq_s32(vqaddq_s32(v_r01, vshlq_n_s32(v_r11, 2)), v_delta), 8);

            vst1q_u16(dst + x, vcombine_u16(vqmovun_s32(v_dst0), vqmovun_s32(v_dst1)));
        }

        return x;
    }
};

struct PyrDownVec_32s16s
{
    int operator()(int** src, short* dst, int, int width) const
    {
        int x = 0;
        const int *row0 = src[0], *row1 = src[1], *row2 = src[2], *row3 = src[3], *row4 = src[4];
        int32x4_t v_delta = vdupq_n_s32(128);

        for( ; x <= width - 8; x += 8 )
        {
            int32x4_t v_r00 = vld1q_s32(row0 + x), v_r01 = vld1q_s32(row0 + x + 4);
            int32x4_t v_r10 = vld1q_s32(row1 + x), v_r11 = vld1q_s32(row1 + x + 4);
            int32x4_t v_r20 = vld1q_s32(row2 + x), v_r21 = vld1q_s32(row2 + x + 4);
            int32x4_t v_r30 = vld1q_s32(row3 + x), v_r31 = vld1q_s32(row3 + x + 4);
            int32x4_t v_r40 = vld1q_s32(row4 + x), v_r41 = vld1q_s32(row4 + x + 4);

            v_r00 = vaddq_s32(vqaddq_s32(v_r00, v_r40), vqaddq_s32(v_r20, v_r20));
            v_r10 = vaddq_s32(vqaddq_s32(v_r10, v_r20), v_r30);
            int32x4_t v_dst0 = vshrq_n_s32(vaddq_s32(vqaddq_s32(v_r00, vshlq_n_s32(v_r10, 2)), v_delta), 8);

            v_r01 = vaddq_s32(vqaddq_s32(v_r01, v_r41), vqaddq_s32(v_r21, v_r21));
            v_r11 = vaddq_s32(vqaddq_s32(v_r11, v_r21), v_r31);
            int32x4_t v_dst1 = vshrq_n_s32(vaddq_s32(vqaddq_s32(v_r01, vshlq_n_s32(v_r11, 2)), v_delta), 8);

            vst1q_s16(dst + x, vcombine_s16(vqmovn_s32(v_dst0), vqmovn_s32(v_dst1)));
        }

        return x;
    }
};

struct PyrDownVec_32f
{
    int operator()(float** src, float* dst, int, int width) const
    {
        int x = 0;
        const float *row0 = src[0], *row1 = src[1], *row2 = src[2], *row3 = src[3], *row4 = src[4];
        float32x4_t v_4 = vdupq_n_f32(4.0f), v_scale = vdupq_n_f32(1.f/256.0f);

        for( ; x <= width - 8; x += 8 )
        {
            float32x4_t v_r0 = vld1q_f32(row0 + x);
            float32x4_t v_r1 = vld1q_f32(row1 + x);
            float32x4_t v_r2 = vld1q_f32(row2 + x);
            float32x4_t v_r3 = vld1q_f32(row3 + x);
            float32x4_t v_r4 = vld1q_f32(row4 + x);

            v_r0 = vaddq_f32(vaddq_f32(v_r0, v_r4), vaddq_f32(v_r2, v_r2));
            v_r1 = vaddq_f32(vaddq_f32(v_r1, v_r2), v_r3);
            vst1q_f32(dst + x, vmulq_f32(vmlaq_f32(v_r0, v_4, v_r1), v_scale));

            v_r0 = vld1q_f32(row0 + x + 4);
            v_r1 = vld1q_f32(row1 + x + 4);
            v_r2 = vld1q_f32(row2 + x + 4);
            v_r3 = vld1q_f32(row3 + x + 4);
            v_r4 = vld1q_f32(row4 + x + 4);

            v_r0 = vaddq_f32(vaddq_f32(v_r0, v_r4), vaddq_f32(v_r2, v_r2));
            v_r1 = vaddq_f32(vaddq_f32(v_r1, v_r2), v_r3);
            vst1q_f32(dst + x + 4, vmulq_f32(vmlaq_f32(v_r0, v_4, v_r1), v_scale));
        }

        return x;
    }
};

struct PyrUpVec_32f
{
    int operator()(float** src, float* dst, int, int width) const
    {
        int x = 0;
        float ** dsts = (float **)dst;
        const float *row0 = src[0], *row1 = src[1], *row2 = src[2];
        float *dst0 = dsts[0], *dst1 = dsts[1];
        float32x4_t v_6 = vdupq_n_f32(6.0f), v_scale = vdupq_n_f32(1.f/64.0f), v_scale4 = vmulq_n_f32(v_scale, 4.0f);

        for( ; x <= width - 8; x += 8 )
        {
            float32x4_t v_r0 = vld1q_f32(row0 + x);
            float32x4_t v_r1 = vld1q_f32(row1 + x);
            float32x4_t v_r2 = vld1q_f32(row2 + x);

            vst1q_f32(dst1 + x, vmulq_f32(v_scale4, vaddq_f32(v_r1, v_r2)));
            vst1q_f32(dst0 + x, vmulq_f32(v_scale, vaddq_f32(vmlaq_f32(v_r0, v_6, v_r1), v_r2)));

            v_r0 = vld1q_f32(row0 + x + 4);
            v_r1 = vld1q_f32(row1 + x + 4);
            v_r2 = vld1q_f32(row2 + x + 4);

            vst1q_f32(dst1 + x + 4, vmulq_f32(v_scale4, vaddq_f32(v_r1, v_r2)));
            vst1q_f32(dst0 + x + 4, vmulq_f32(v_scale, vaddq_f32(vmlaq_f32(v_r0, v_6, v_r1), v_r2)));
        }

        return x;
    }
};

#else

typedef NoVec<int, uchar> PyrDownVec_32s8u;
typedef NoVec<int, ushort> PyrDownVec_32s16u;
typedef NoVec<int, short> PyrDownVec_32s16s;
typedef NoVec<float, float> PyrDownVec_32f;

typedef NoVec<float, float> PyrUpVec_32f;

#endif

template<class CastOp, class VecOp> void
pyrDown_( const Mat& _src, Mat& _dst, int borderType )
{
    const int PD_SZ = 5;
    typedef typename CastOp::type1 WT;
    typedef typename CastOp::rtype T;

    CV_Assert( !_src.empty() );
    Size ssize = _src.size(), dsize = _dst.size();
    int cn = _src.channels();
    int bufstep = (int)alignSize(dsize.width*cn, 16);
    AutoBuffer<WT> _buf(bufstep*PD_SZ + 16);
    WT* buf = alignPtr((WT*)_buf, 16);
    int tabL[CV_CN_MAX*(PD_SZ+2)], tabR[CV_CN_MAX*(PD_SZ+2)];
    AutoBuffer<int> _tabM(dsize.width*cn);
    int* tabM = _tabM;
    WT* rows[PD_SZ];
    CastOp castOp;
    VecOp vecOp;

    CV_Assert( ssize.width > 0 && ssize.height > 0 &&
               std::abs(dsize.width*2 - ssize.width) <= 2 &&
               std::abs(dsize.height*2 - ssize.height) <= 2 );
    int k, x, sy0 = -PD_SZ/2, sy = sy0, width0 = std::min((ssize.width-PD_SZ/2-1)/2 + 1, dsize.width);

    for( x = 0; x <= PD_SZ+1; x++ )
    {
        int sx0 = borderInterpolate(x - PD_SZ/2, ssize.width, borderType)*cn;
        int sx1 = borderInterpolate(x + width0*2 - PD_SZ/2, ssize.width, borderType)*cn;
        for( k = 0; k < cn; k++ )
        {
            tabL[x*cn + k] = sx0 + k;
            tabR[x*cn + k] = sx1 + k;
        }
    }

    ssize.width *= cn;
    dsize.width *= cn;
    width0 *= cn;

    for( x = 0; x < dsize.width; x++ )
        tabM[x] = (x/cn)*2*cn + x % cn;

    for( int y = 0; y < dsize.height; y++ )
    {
        T* dst = _dst.ptr<T>(y);
        WT *row0, *row1, *row2, *row3, *row4;

        // fill the ring buffer (horizontal convolution and decimation)
        for( ; sy <= y*2 + 2; sy++ )
        {
            WT* row = buf + ((sy - sy0) % PD_SZ)*bufstep;
            int _sy = borderInterpolate(sy, ssize.height, borderType);
            const T* src = _src.ptr<T>(_sy);
            int limit = cn;
            const int* tab = tabL;

            for( x = 0;;)
            {
                for( ; x < limit; x++ )
                {
                    row[x] = src[tab[x+cn*2]]*6 + (src[tab[x+cn]] + src[tab[x+cn*3]])*4 +
                        src[tab[x]] + src[tab[x+cn*4]];
                }

                if( x == dsize.width )
                    break;

                if( cn == 1 )
                {
                    for( ; x < width0; x++ )
                        row[x] = src[x*2]*6 + (src[x*2 - 1] + src[x*2 + 1])*4 +
                            src[x*2 - 2] + src[x*2 + 2];
                }
                else if( cn == 3 )
                {
                    for( ; x < width0; x += 3 )
                    {
                        const T* s = src + x*2;
                        WT t0 = s[0]*6 + (s[-3] + s[3])*4 + s[-6] + s[6];
                        WT t1 = s[1]*6 + (s[-2] + s[4])*4 + s[-5] + s[7];
                        WT t2 = s[2]*6 + (s[-1] + s[5])*4 + s[-4] + s[8];
                        row[x] = t0; row[x+1] = t1; row[x+2] = t2;
                    }
                }
                else if( cn == 4 )
                {
                    for( ; x < width0; x += 4 )
                    {
                        const T* s = src + x*2;
                        WT t0 = s[0]*6 + (s[-4] + s[4])*4 + s[-8] + s[8];
                        WT t1 = s[1]*6 + (s[-3] + s[5])*4 + s[-7] + s[9];
                        row[x] = t0; row[x+1] = t1;
                        t0 = s[2]*6 + (s[-2] + s[6])*4 + s[-6] + s[10];
                        t1 = s[3]*6 + (s[-1] + s[7])*4 + s[-5] + s[11];
                        row[x+2] = t0; row[x+3] = t1;
                    }
                }
                else
                {
                    for( ; x < width0; x++ )
                    {
                        int sx = tabM[x];
                        row[x] = src[sx]*6 + (src[sx - cn] + src[sx + cn])*4 +
                            src[sx - cn*2] + src[sx + cn*2];
                    }
                }

                limit = dsize.width;
                tab = tabR - x;
            }
        }

        // do vertical convolution and decimation and write the result to the destination image
        for( k = 0; k < PD_SZ; k++ )
            rows[k] = buf + ((y*2 - PD_SZ/2 + k - sy0) % PD_SZ)*bufstep;
        row0 = rows[0]; row1 = rows[1]; row2 = rows[2]; row3 = rows[3]; row4 = rows[4];

        x = vecOp(rows, dst, (int)_dst.step, dsize.width);
        for( ; x < dsize.width; x++ )
            dst[x] = castOp(row2[x]*6 + (row1[x] + row3[x])*4 + row0[x] + row4[x]);
    }
}


template<class CastOp, class VecOp> void
pyrUp_( const Mat& _src, Mat& _dst, int)
{
    const int PU_SZ = 3;
    typedef typename CastOp::type1 WT;
    typedef typename CastOp::rtype T;

    Size ssize = _src.size(), dsize = _dst.size();
    int cn = _src.channels();
    int bufstep = (int)alignSize((dsize.width+1)*cn, 16);
    AutoBuffer<WT> _buf(bufstep*PU_SZ + 16);
    WT* buf = alignPtr((WT*)_buf, 16);
    AutoBuffer<int> _dtab(ssize.width*cn);
    int* dtab = _dtab;
    WT* rows[PU_SZ];
    T* dsts[2];
    CastOp castOp;
    VecOp vecOp;

    CV_Assert( std::abs(dsize.width - ssize.width*2) == dsize.width % 2 &&
               std::abs(dsize.height - ssize.height*2) == dsize.height % 2);
    int k, x, sy0 = -PU_SZ/2, sy = sy0;

    ssize.width *= cn;
    dsize.width *= cn;

    for( x = 0; x < ssize.width; x++ )
        dtab[x] = (x/cn)*2*cn + x % cn;

    for( int y = 0; y < ssize.height; y++ )
    {
        T* dst0 = _dst.ptr<T>(y*2);
        T* dst1 = _dst.ptr<T>(std::min(y*2+1, dsize.height-1));
        WT *row0, *row1, *row2;

        // fill the ring buffer (horizontal convolution and decimation)
        for( ; sy <= y + 1; sy++ )
        {
            WT* row = buf + ((sy - sy0) % PU_SZ)*bufstep;
            int _sy = borderInterpolate(sy*2, dsize.height, BORDER_REFLECT_101)/2;
            const T* src = _src.ptr<T>(_sy);

            if( ssize.width == cn )
            {
                for( x = 0; x < cn; x++ )
                    row[x] = row[x + cn] = src[x]*8;
                continue;
            }

            for( x = 0; x < cn; x++ )
            {
                int dx = dtab[x];
                WT t0 = src[x]*6 + src[x + cn]*2;
                WT t1 = (src[x] + src[x + cn])*4;
                row[dx] = t0; row[dx + cn] = t1;
                dx = dtab[ssize.width - cn + x];
                int sx = ssize.width - cn + x;
                t0 = src[sx - cn] + src[sx]*7;
                t1 = src[sx]*8;
                row[dx] = t0; row[dx + cn] = t1;
            }

            for( x = cn; x < ssize.width - cn; x++ )
            {
                int dx = dtab[x];
                WT t0 = src[x-cn] + src[x]*6 + src[x+cn];
                WT t1 = (src[x] + src[x+cn])*4;
                row[dx] = t0;
                row[dx+cn] = t1;
            }
        }

        // do vertical convolution and decimation and write the result to the destination image
        for( k = 0; k < PU_SZ; k++ )
            rows[k] = buf + ((y - PU_SZ/2 + k - sy0) % PU_SZ)*bufstep;
        row0 = rows[0]; row1 = rows[1]; row2 = rows[2];
        dsts[0] = dst0; dsts[1] = dst1;

        x = vecOp(rows, (T*)dsts, (int)_dst.step, dsize.width);
        for( ; x < dsize.width; x++ )
        {
            T t1 = castOp((row1[x] + row2[x])*4);
            T t0 = castOp(row0[x] + row1[x]*6 + row2[x]);
            dst1[x] = t1; dst0[x] = t0;
        }
    }
}

typedef void (*PyrFunc)(const Mat&, Mat&, int);

#ifdef HAVE_OPENCL

static bool ocl_pyrDown( InputArray _src, OutputArray _dst, const Size& _dsz, int borderType)
{
    int type = _src.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);

    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
    if (cn > 4 || (depth == CV_64F && !doubleSupport))
        return false;

    Size ssize = _src.size();
    Size dsize = _dsz.area() == 0 ? Size((ssize.width + 1) / 2, (ssize.height + 1) / 2) : _dsz;
    if (dsize.height < 2 || dsize.width < 2)
        return false;

    CV_Assert( ssize.width > 0 && ssize.height > 0 &&
            std::abs(dsize.width*2 - ssize.width) <= 2 &&
            std::abs(dsize.height*2 - ssize.height) <= 2 );

    UMat src = _src.getUMat();
    _dst.create( dsize, src.type() );
    UMat dst = _dst.getUMat();

    int float_depth = depth == CV_64F ? CV_64F : CV_32F;
    const int local_size = 256;
    int kercn = 1;
    if (depth == CV_8U && float_depth == CV_32F && cn == 1 && ocl::Device::getDefault().isIntel())
        kercn = 4;
    const char * const borderMap[] = { "BORDER_CONSTANT", "BORDER_REPLICATE", "BORDER_REFLECT", "BORDER_WRAP",
                                       "BORDER_REFLECT_101" };
    char cvt[2][50];
    String buildOptions = format(
            "-D T=%s -D FT=%s -D convertToT=%s -D convertToFT=%s%s "
            "-D T1=%s -D cn=%d -D kercn=%d -D fdepth=%d -D %s -D LOCAL_SIZE=%d",
            ocl::typeToStr(type), ocl::typeToStr(CV_MAKETYPE(float_depth, cn)),
            ocl::convertTypeStr(float_depth, depth, cn, cvt[0]),
            ocl::convertTypeStr(depth, float_depth, cn, cvt[1]),
            doubleSupport ? " -D DOUBLE_SUPPORT" : "", ocl::typeToStr(depth),
            cn, kercn, float_depth, borderMap[borderType], local_size
    );
    ocl::Kernel k("pyrDown", ocl::imgproc::pyr_down_oclsrc, buildOptions);
    if (k.empty())
        return false;

    k.args(ocl::KernelArg::ReadOnly(src), ocl::KernelArg::WriteOnly(dst));

    size_t localThreads[2]  = { local_size/kercn, 1 };
    size_t globalThreads[2] = { (src.cols + (kercn-1))/kercn, (dst.rows + 1) / 2 };
    return k.run(2, globalThreads, localThreads, false);
}

static bool ocl_pyrUp( InputArray _src, OutputArray _dst, const Size& _dsz, int borderType)
{
    int type = _src.type(), depth = CV_MAT_DEPTH(type), channels = CV_MAT_CN(type);

    if (channels > 4 || borderType != BORDER_DEFAULT)
        return false;

    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
    if (depth == CV_64F && !doubleSupport)
        return false;

    Size ssize = _src.size();
    if ((_dsz.area() != 0) && (_dsz != Size(ssize.width * 2, ssize.height * 2)))
        return false;

    UMat src = _src.getUMat();
    Size dsize = Size(ssize.width * 2, ssize.height * 2);
    _dst.create( dsize, src.type() );
    UMat dst = _dst.getUMat();

    int float_depth = depth == CV_64F ? CV_64F : CV_32F;
    const int local_size = 16;
    char cvt[2][50];
    String buildOptions = format(
            "-D T=%s -D FT=%s -D convertToT=%s -D convertToFT=%s%s "
            "-D T1=%s -D cn=%d -D LOCAL_SIZE=%d",
            ocl::typeToStr(type), ocl::typeToStr(CV_MAKETYPE(float_depth, channels)),
            ocl::convertTypeStr(float_depth, depth, channels, cvt[0]),
            ocl::convertTypeStr(depth, float_depth, channels, cvt[1]),
            doubleSupport ? " -D DOUBLE_SUPPORT" : "",
            ocl::typeToStr(depth), channels, local_size
    );
    size_t globalThreads[2] = { dst.cols, dst.rows };
    size_t localThreads[2] = { local_size, local_size };
    ocl::Kernel k;
    if (ocl::Device::getDefault().isIntel() && channels == 1)
    {
        k.create("pyrUp_unrolled", ocl::imgproc::pyr_up_oclsrc, buildOptions);
        globalThreads[0] = dst.cols/2; globalThreads[1] = dst.rows/2;
    }
    else
        k.create("pyrUp", ocl::imgproc::pyr_up_oclsrc, buildOptions);

    if (k.empty())
        return false;

    k.args(ocl::KernelArg::ReadOnly(src), ocl::KernelArg::WriteOnly(dst));
    return k.run(2, globalThreads, localThreads, false);
}

#endif

}

void cv::pyrDown( InputArray _src, OutputArray _dst, const Size& _dsz, int borderType )
{
    CV_Assert(borderType != BORDER_CONSTANT);

    CV_OCL_RUN(_src.dims() <= 2 && _dst.isUMat(),
               ocl_pyrDown(_src, _dst, _dsz, borderType))

    Mat src = _src.getMat();
    Size dsz = _dsz.area() == 0 ? Size((src.cols + 1)/2, (src.rows + 1)/2) : _dsz;
    _dst.create( dsz, src.type() );
    Mat dst = _dst.getMat();
    int depth = src.depth();

#ifdef HAVE_TEGRA_OPTIMIZATION
    if(borderType == BORDER_DEFAULT && tegra::pyrDown(src, dst))
        return;
#endif

#if IPP_VERSION_X100 >= 801 && 0
    bool isolated = (borderType & BORDER_ISOLATED) != 0;
    int borderTypeNI = borderType & ~BORDER_ISOLATED;
    if (borderTypeNI == BORDER_DEFAULT && (!src.isSubmatrix() || isolated) && dsz == Size((src.cols + 1)/2, (src.rows + 1)/2))
    {
        typedef IppStatus (CV_STDCALL * ippiPyrDown)(const void* pSrc, int srcStep, void* pDst, int dstStep, IppiSize srcRoi, Ipp8u* buffer);
        int type = src.type();
        CV_SUPPRESS_DEPRECATED_START
        ippiPyrDown pyrDownFunc = type == CV_8UC1 ? (ippiPyrDown) ippiPyrDown_Gauss5x5_8u_C1R :
                                  type == CV_8UC3 ? (ippiPyrDown) ippiPyrDown_Gauss5x5_8u_C3R :
                                  type == CV_32FC1 ? (ippiPyrDown) ippiPyrDown_Gauss5x5_32f_C1R :
                                  type == CV_32FC3 ? (ippiPyrDown) ippiPyrDown_Gauss5x5_32f_C3R : 0;
        CV_SUPPRESS_DEPRECATED_END

        if (pyrDownFunc)
        {
            int bufferSize;
            IppiSize srcRoi = { src.cols, src.rows };
            IppDataType dataType = depth == CV_8U ? ipp8u : ipp32f;
            CV_SUPPRESS_DEPRECATED_START
            IppStatus ok = ippiPyrDownGetBufSize_Gauss5x5(srcRoi.width, dataType, src.channels(), &bufferSize);
            CV_SUPPRESS_DEPRECATED_END
            if (ok >= 0)
            {
                Ipp8u* buffer = ippsMalloc_8u(bufferSize);
                ok = pyrDownFunc(src.data, (int) src.step, dst.data, (int) dst.step, srcRoi, buffer);
                ippsFree(buffer);

                if (ok >= 0)
                    return;
                setIppErrorStatus();
            }
        }
    }
#endif

    PyrFunc func = 0;
    if( depth == CV_8U )
        func = pyrDown_<FixPtCast<uchar, 8>, PyrDownVec_32s8u>;
    else if( depth == CV_16S )
        func = pyrDown_<FixPtCast<short, 8>, PyrDownVec_32s16s >;
    else if( depth == CV_16U )
        func = pyrDown_<FixPtCast<ushort, 8>, PyrDownVec_32s16u >;
    else if( depth == CV_32F )
        func = pyrDown_<FltCast<float, 8>, PyrDownVec_32f>;
    else if( depth == CV_64F )
        func = pyrDown_<FltCast<double, 8>, NoVec<double, double> >;
    else
        CV_Error( CV_StsUnsupportedFormat, "" );

    func( src, dst, borderType );
}

void cv::pyrUp( InputArray _src, OutputArray _dst, const Size& _dsz, int borderType )
{
    CV_Assert(borderType == BORDER_DEFAULT);

    CV_OCL_RUN(_src.dims() <= 2 && _dst.isUMat(),
               ocl_pyrUp(_src, _dst, _dsz, borderType))

    Mat src = _src.getMat();
    Size dsz = _dsz.area() == 0 ? Size(src.cols*2, src.rows*2) : _dsz;
    _dst.create( dsz, src.type() );
    Mat dst = _dst.getMat();
    int depth = src.depth();

#ifdef HAVE_TEGRA_OPTIMIZATION
    if(borderType == BORDER_DEFAULT && tegra::pyrUp(src, dst))
        return;
#endif

#if IPP_VERSION_X100 >= 801 && 0
    bool isolated = (borderType & BORDER_ISOLATED) != 0;
    int borderTypeNI = borderType & ~BORDER_ISOLATED;
    if (borderTypeNI == BORDER_DEFAULT && (!src.isSubmatrix() || isolated) && dsz == Size(src.cols*2, src.rows*2))
    {
        typedef IppStatus (CV_STDCALL * ippiPyrUp)(const void* pSrc, int srcStep, void* pDst, int dstStep, IppiSize srcRoi, Ipp8u* buffer);
        int type = src.type();
        CV_SUPPRESS_DEPRECATED_START
        ippiPyrUp pyrUpFunc = type == CV_8UC1 ? (ippiPyrUp) ippiPyrUp_Gauss5x5_8u_C1R :
                              type == CV_8UC3 ? (ippiPyrUp) ippiPyrUp_Gauss5x5_8u_C3R :
                              type == CV_32FC1 ? (ippiPyrUp) ippiPyrUp_Gauss5x5_32f_C1R :
                              type == CV_32FC3 ? (ippiPyrUp) ippiPyrUp_Gauss5x5_32f_C3R : 0;
        CV_SUPPRESS_DEPRECATED_END

        if (pyrUpFunc)
        {
            int bufferSize;
            IppiSize srcRoi = { src.cols, src.rows };
            IppDataType dataType = depth == CV_8U ? ipp8u : ipp32f;
            CV_SUPPRESS_DEPRECATED_START
            IppStatus ok = ippiPyrUpGetBufSize_Gauss5x5(srcRoi.width, dataType, src.channels(), &bufferSize);
            CV_SUPPRESS_DEPRECATED_END
            if (ok >= 0)
            {
                Ipp8u* buffer = ippsMalloc_8u(bufferSize);
                ok = pyrUpFunc(src.data, (int) src.step, dst.data, (int) dst.step, srcRoi, buffer);
                ippsFree(buffer);

                if (ok >= 0)
                    return;
                setIppErrorStatus();
            }
        }
    }
#endif

    PyrFunc func = 0;
    if( depth == CV_8U )
        func = pyrUp_<FixPtCast<uchar, 6>, NoVec<int, uchar> >;
    else if( depth == CV_16S )
        func = pyrUp_<FixPtCast<short, 6>, NoVec<int, short> >;
    else if( depth == CV_16U )
        func = pyrUp_<FixPtCast<ushort, 6>, NoVec<int, ushort> >;
    else if( depth == CV_32F )
        func = pyrUp_<FltCast<float, 6>, PyrUpVec_32f >;
    else if( depth == CV_64F )
        func = pyrUp_<FltCast<double, 6>, NoVec<double, double> >;
    else
        CV_Error( CV_StsUnsupportedFormat, "" );

    func( src, dst, borderType );
}

void cv::buildPyramid( InputArray _src, OutputArrayOfArrays _dst, int maxlevel, int borderType )
{
    CV_Assert(borderType != BORDER_CONSTANT);

    if (_src.dims() <= 2 && _dst.isUMatVector())
    {
        UMat src = _src.getUMat();
        _dst.create( maxlevel + 1, 1, 0 );
        _dst.getUMatRef(0) = src;
        for( int i = 1; i <= maxlevel; i++ )
            pyrDown( _dst.getUMatRef(i-1), _dst.getUMatRef(i), Size(), borderType );
        return;
    }

    Mat src = _src.getMat();
    _dst.create( maxlevel + 1, 1, 0 );
    _dst.getMatRef(0) = src;

    int i=1;

#if IPP_VERSION_X100 >= 801 && 0
    bool isolated = (borderType & BORDER_ISOLATED) != 0;
    int borderTypeNI = borderType & ~BORDER_ISOLATED;
    if (borderTypeNI == BORDER_DEFAULT && (!src.isSubmatrix() || isolated))
    {
        typedef IppStatus (CV_STDCALL * ippiPyramidLayerDownInitAlloc)(void** ppState, IppiSize srcRoi, Ipp32f rate, void* pKernel, int kerSize, int mode);
        typedef IppStatus (CV_STDCALL * ippiPyramidLayerDown)(void* pSrc, int srcStep, IppiSize srcRoiSize, void* pDst, int dstStep, IppiSize dstRoiSize, void* pState);
        typedef IppStatus (CV_STDCALL * ippiPyramidLayerDownFree)(void* pState);

        int type = src.type();
        int depth = src.depth();
        ippiPyramidLayerDownInitAlloc pyrInitAllocFunc = 0;
        ippiPyramidLayerDown pyrDownFunc = 0;
        ippiPyramidLayerDownFree pyrFreeFunc = 0;

        if (type == CV_8UC1)
        {
            pyrInitAllocFunc = (ippiPyramidLayerDownInitAlloc) ippiPyramidLayerDownInitAlloc_8u_C1R;
            pyrDownFunc = (ippiPyramidLayerDown) ippiPyramidLayerDown_8u_C1R;
            pyrFreeFunc = (ippiPyramidLayerDownFree) ippiPyramidLayerDownFree_8u_C1R;
        }
        else if (type == CV_8UC3)
        {
            pyrInitAllocFunc = (ippiPyramidLayerDownInitAlloc) ippiPyramidLayerDownInitAlloc_8u_C3R;
            pyrDownFunc = (ippiPyramidLayerDown) ippiPyramidLayerDown_8u_C3R;
            pyrFreeFunc = (ippiPyramidLayerDownFree) ippiPyramidLayerDownFree_8u_C3R;
        }
        else if (type == CV_32FC1)
        {
            pyrInitAllocFunc = (ippiPyramidLayerDownInitAlloc) ippiPyramidLayerDownInitAlloc_32f_C1R;
            pyrDownFunc = (ippiPyramidLayerDown) ippiPyramidLayerDown_32f_C1R;
            pyrFreeFunc = (ippiPyramidLayerDownFree) ippiPyramidLayerDownFree_32f_C1R;
        }
        else if (type == CV_32FC3)
        {
            pyrInitAllocFunc = (ippiPyramidLayerDownInitAlloc) ippiPyramidLayerDownInitAlloc_32f_C3R;
            pyrDownFunc = (ippiPyramidLayerDown) ippiPyramidLayerDown_32f_C3R;
            pyrFreeFunc = (ippiPyramidLayerDownFree) ippiPyramidLayerDownFree_32f_C3R;
        }

        if (pyrInitAllocFunc && pyrDownFunc && pyrFreeFunc)
        {
            float rate = 2.f;
            IppiSize srcRoi = { src.cols, src.rows };
            IppiPyramid *gPyr;
            IppStatus ok = ippiPyramidInitAlloc(&gPyr, maxlevel + 1, srcRoi, rate);

            Ipp16s iKernel[5] = { 1, 4, 6, 4, 1 };
            Ipp32f fKernel[5] = { 1.f, 4.f, 6.f, 4.f, 1.f };
            void* kernel = depth >= CV_32F ? (void*) fKernel : (void*) iKernel;

            if (ok >= 0) ok = pyrInitAllocFunc((void**) &(gPyr->pState), srcRoi, rate, kernel, 5, IPPI_INTER_LINEAR);
            if (ok >= 0)
            {
                gPyr->pImage[0] = src.data;
                gPyr->pStep[0] = (int) src.step;
                gPyr->pRoi[0] = srcRoi;
                for( ; i <= maxlevel; i++ )
                {
                    IppiSize dstRoi;
                    ok = ippiGetPyramidDownROI(gPyr->pRoi[i-1], &dstRoi, rate);
                    Mat& dst = _dst.getMatRef(i);
                    dst.create(Size(dstRoi.width, dstRoi.height), type);
                    gPyr->pImage[i] = dst.data;
                    gPyr->pStep[i] = (int) dst.step;
                    gPyr->pRoi[i] = dstRoi;

                    if (ok >= 0) ok = pyrDownFunc(gPyr->pImage[i-1], gPyr->pStep[i-1], gPyr->pRoi[i-1],
                                                  gPyr->pImage[i], gPyr->pStep[i], gPyr->pRoi[i], gPyr->pState);

                    if (ok < 0)
                    {
                        setIppErrorStatus();
                        break;
                    }
                }
                pyrFreeFunc(gPyr->pState);
            }
            else
                setIppErrorStatus();

            ippiPyramidFree(gPyr);
        }
    }
#endif
    for( ; i <= maxlevel; i++ )
        pyrDown( _dst.getMatRef(i-1), _dst.getMatRef(i), Size(), borderType );
}

CV_IMPL void cvPyrDown( const void* srcarr, void* dstarr, int _filter )
{
    cv::Mat src = cv::cvarrToMat(srcarr), dst = cv::cvarrToMat(dstarr);

    CV_Assert( _filter == CV_GAUSSIAN_5x5 && src.type() == dst.type());
    cv::pyrDown( src, dst, dst.size() );
}

CV_IMPL void cvPyrUp( const void* srcarr, void* dstarr, int _filter )
{
    cv::Mat src = cv::cvarrToMat(srcarr), dst = cv::cvarrToMat(dstarr);

    CV_Assert( _filter == CV_GAUSSIAN_5x5 && src.type() == dst.type());
    cv::pyrUp( src, dst, dst.size() );
}


CV_IMPL void
cvReleasePyramid( CvMat*** _pyramid, int extra_layers )
{
    if( !_pyramid )
        CV_Error( CV_StsNullPtr, "" );

    if( *_pyramid )
        for( int i = 0; i <= extra_layers; i++ )
            cvReleaseMat( &(*_pyramid)[i] );

    cvFree( _pyramid );
}


CV_IMPL CvMat**
cvCreatePyramid( const CvArr* srcarr, int extra_layers, double rate,
                 const CvSize* layer_sizes, CvArr* bufarr,
                 int calc, int filter )
{
    const float eps = 0.1f;
    uchar* ptr = 0;

    CvMat stub, *src = cvGetMat( srcarr, &stub );

    if( extra_layers < 0 )
        CV_Error( CV_StsOutOfRange, "The number of extra layers must be non negative" );

    int i, layer_step, elem_size = CV_ELEM_SIZE(src->type);
    CvSize layer_size, size = cvGetMatSize(src);

    if( bufarr )
    {
        CvMat bstub, *buf;
        int bufsize = 0;

        buf = cvGetMat( bufarr, &bstub );
        bufsize = buf->rows*buf->cols*CV_ELEM_SIZE(buf->type);
        layer_size = size;
        for( i = 1; i <= extra_layers; i++ )
        {
            if( !layer_sizes )
            {
                layer_size.width = cvRound(layer_size.width*rate+eps);
                layer_size.height = cvRound(layer_size.height*rate+eps);
            }
            else
                layer_size = layer_sizes[i-1];
            layer_step = layer_size.width*elem_size;
            bufsize -= layer_step*layer_size.height;
        }

        if( bufsize < 0 )
            CV_Error( CV_StsOutOfRange, "The buffer is too small to fit the pyramid" );
        ptr = buf->data.ptr;
    }

    CvMat** pyramid = (CvMat**)cvAlloc( (extra_layers+1)*sizeof(pyramid[0]) );
    memset( pyramid, 0, (extra_layers+1)*sizeof(pyramid[0]) );

    pyramid[0] = cvCreateMatHeader( size.height, size.width, src->type );
    cvSetData( pyramid[0], src->data.ptr, src->step );
    layer_size = size;

    for( i = 1; i <= extra_layers; i++ )
    {
        if( !layer_sizes )
        {
            layer_size.width = cvRound(layer_size.width*rate + eps);
            layer_size.height = cvRound(layer_size.height*rate + eps);
        }
        else
            layer_size = layer_sizes[i];

        if( bufarr )
        {
            pyramid[i] = cvCreateMatHeader( layer_size.height, layer_size.width, src->type );
            layer_step = layer_size.width*elem_size;
            cvSetData( pyramid[i], ptr, layer_step );
            ptr += layer_step*layer_size.height;
        }
        else
            pyramid[i] = cvCreateMat( layer_size.height, layer_size.width, src->type );

        if( calc )
            cvPyrDown( pyramid[i-1], pyramid[i], filter );
            //cvResize( pyramid[i-1], pyramid[i], CV_INTER_LINEAR );
    }

    return pyramid;
}

/* End of file. */