#ifndef OPENCV_OPENVX_HAL_HPP_INCLUDED
#define OPENCV_OPENVX_HAL_HPP_INCLUDED

#include "opencv2/core/hal/interface.h"

#include "VX/vx.h"
#include "VX/vxu.h"

#include <string>
#include <vector>

#include <algorithm>
#include <opencv2/core/saturate.hpp>

//==================================================================================================
// utility
// ...

#if 0
#include <cstdio>
#define PRINT(...) printf(__VA_ARGS__)
#else
#define PRINT(...)
#endif

#if __cplusplus >= 201103L
#include <chrono>
struct Tick
{
    typedef std::chrono::time_point<std::chrono::steady_clock> point_t;
    point_t start;
    point_t point;
    Tick()
    {
        start = std::chrono::steady_clock::now();
        point = std::chrono::steady_clock::now();
    }
    inline int one()
    {
        point_t old = point;
        point = std::chrono::steady_clock::now();
        return std::chrono::duration_cast<std::chrono::microseconds>(point - old).count();
    }
    inline int total()
    {
        return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::steady_clock::now() - start).count();
    }
};
#endif

//==================================================================================================
// One more OpenVX C++ binding :-)
// ...

template <typename T>
struct VX_Traits
{
    enum {
        ImgType = 0,
        DataType = 0
    };
};

template <>
struct VX_Traits<uchar>
{
    enum {
        ImgType = VX_DF_IMAGE_U8,
        DataType = VX_TYPE_UINT8
    };
};

template <>
struct VX_Traits<ushort>
{
    enum {
        ImgType = VX_DF_IMAGE_U16,
        DataType = VX_TYPE_UINT16
    };
};

template <>
struct VX_Traits<short>
{
    enum {
        ImgType = VX_DF_IMAGE_S16,
        DataType = VX_TYPE_INT16
    };
};

template <>
struct VX_Traits<float>
{
    enum {
        ImgType = 0,
        DataType = VX_TYPE_FLOAT32
    };
};


struct vxContext;
struct vxImage;
struct vxErr;


struct vxErr
{
    vx_status status;
    std::string msg;
    vxErr(vx_status status_, const std::string & msg_) : status(status_), msg(msg_) {}
    void check()
    {
        if (status != VX_SUCCESS)
            throw *this;
    }
    void print()
    {
        PRINT("OpenVX HAL impl error: %d (%s)\n", status, msg.c_str());
    }
    static void check(vx_context ctx)
    {
        vxErr(vxGetStatus((vx_reference)ctx), "context check").check();
    }
    static void check(vx_image img)
    {
        vxErr(vxGetStatus((vx_reference)img), "image check").check();
    }
    static void check(vx_matrix mtx)
    {
        vxErr(vxGetStatus((vx_reference)mtx), "matrix check").check();
    }
    static void check(vx_convolution cnv)
    {
        vxErr(vxGetStatus((vx_reference)cnv), "convolution check").check();
    }
    static void check(vx_status s)
    {
        vxErr(s, "status check").check();
    }
};


struct vxContext
{
    vx_context ctx;
    static vxContext * getContext();
private:
    vxContext()
    {
        ctx = vxCreateContext();
        vxErr::check(ctx);
    }
    ~vxContext()
    {
        vxReleaseContext(&ctx);
    }
};


struct vxImage
{
    vx_image img;

    template <typename T>
    vxImage(vxContext &ctx, const T *data, size_t step, int w, int h)
    {
        if (h == 1)
            step = w * sizeof(T);
        vx_imagepatch_addressing_t addr;
        addr.dim_x = w;
        addr.dim_y = h;
        addr.stride_x = sizeof(T);
        addr.stride_y = (vx_int32)step;
        addr.scale_x = VX_SCALE_UNITY;
        addr.scale_y = VX_SCALE_UNITY;
        addr.step_x = 1;
        addr.step_y = 1;
        void *ptrs[] = { (void*)data };
        img = vxCreateImageFromHandle(ctx.ctx, VX_Traits<T>::ImgType, &addr, ptrs, VX_MEMORY_TYPE_HOST);
        vxErr::check(img);
    }
    vxImage(vxContext &ctx, int imgType, const uchar *data, size_t step, int w, int h)
    {
        if (h == 1)
            step = w;
        vx_imagepatch_addressing_t addr[4];
        void *ptrs[4];
        switch (imgType)
        {
        case VX_DF_IMAGE_U8:
        case VX_DF_IMAGE_U16:
        case VX_DF_IMAGE_S16:
        case VX_DF_IMAGE_U32:
        case VX_DF_IMAGE_S32:
        case VX_DF_IMAGE_RGB:
        case VX_DF_IMAGE_RGBX:
        case VX_DF_IMAGE_UYVY:
        case VX_DF_IMAGE_YUYV:
            addr[0].dim_x = w;
            addr[0].dim_y = h;
            addr[0].stride_x = imgType == VX_DF_IMAGE_U8 ? 1 :
                imgType == VX_DF_IMAGE_RGB ? 3 :
                (imgType == VX_DF_IMAGE_U16 || imgType == VX_DF_IMAGE_S16) ? 2 : 4;
            addr[0].stride_y = (vx_int32)step;
            addr[0].scale_x = VX_SCALE_UNITY;
            addr[0].scale_y = VX_SCALE_UNITY;
            addr[0].step_x = (imgType == VX_DF_IMAGE_UYVY || imgType == VX_DF_IMAGE_YUYV) ? 2 : 1;
            addr[0].step_y = 1;
            ptrs[0] = (void*)data;
            break;
        case VX_DF_IMAGE_NV12:
        case VX_DF_IMAGE_NV21:
            addr[0].dim_x = w;
            addr[0].dim_y = h;
            addr[0].stride_x = 1;
            addr[0].stride_y = (vx_int32)step;
            addr[0].scale_x = VX_SCALE_UNITY;
            addr[0].scale_y = VX_SCALE_UNITY;
            addr[0].step_x = 1;
            addr[0].step_y = 1;
            ptrs[0] = (void*)data;
            addr[1].dim_x = (w + 1) / 2;
            addr[1].dim_y = (h + 1) / 2;
            addr[1].stride_x = 2;
            addr[1].stride_y = (vx_int32)step;
            addr[1].scale_x = VX_SCALE_UNITY;
            addr[1].scale_y = VX_SCALE_UNITY;
            addr[1].step_x = 2;
            addr[1].step_y = 2;
            ptrs[1] = (void*)(data + h * step);
            break;
        case VX_DF_IMAGE_IYUV:
        case VX_DF_IMAGE_YUV4:
            addr[0].dim_x = w;
            addr[0].dim_y = h;
            addr[0].stride_x = 1;
            addr[0].stride_y = (vx_int32)step;
            addr[0].scale_x = VX_SCALE_UNITY;
            addr[0].scale_y = VX_SCALE_UNITY;
            addr[0].step_x = 1;
            addr[0].step_y = 1;
            ptrs[0] = (void*)data;
            addr[1].dim_x = imgType == VX_DF_IMAGE_YUV4 ? w : (w + 1) / 2;
            addr[1].dim_y = imgType == VX_DF_IMAGE_YUV4 ? h : (h + 1) / 2;
            addr[1].stride_x = 1;
            addr[1].stride_y = (vx_int32)step;
            addr[1].scale_x = VX_SCALE_UNITY;
            addr[1].scale_y = VX_SCALE_UNITY;
            addr[1].step_x = imgType == VX_DF_IMAGE_YUV4 ? 1 : 2;
            addr[1].step_y = imgType == VX_DF_IMAGE_YUV4 ? 1 : 2;
            ptrs[1] = (void*)(data + h * step);
            addr[2].dim_x = addr[1].dim_x;
            addr[2].dim_y = addr[1].dim_y;
            addr[2].stride_x = 1;
            addr[2].stride_y = (vx_int32)step;
            addr[2].scale_x = VX_SCALE_UNITY;
            addr[2].scale_y = VX_SCALE_UNITY;
            addr[2].step_x = addr[1].step_x;
            addr[2].step_y = addr[1].step_y;
            ptrs[2] = (void*)(data + (h + addr[1].dim_y) * step);
            break;
        default:
            vxErr(VX_ERROR_INVALID_PARAMETERS, "Bad image format").check();
        }
        img = vxCreateImageFromHandle(ctx.ctx, imgType, addr, ptrs, VX_MEMORY_TYPE_HOST);
        vxErr::check(img);
    }
    ~vxImage()
    {
        vxErr::check(vxSwapImageHandle(img, NULL, NULL, 1));
        vxReleaseImage(&img);
    }
};

struct vxMatrix
{
    vx_matrix mtx;

    template <typename T>
    vxMatrix(vxContext &ctx, const T *data, int w, int h)
    {
        mtx = vxCreateMatrix(ctx.ctx, VX_Traits<T>::DataType, w, h);
        vxErr::check(mtx);
        vxErr::check(vxCopyMatrix(mtx, const_cast<T*>(data), VX_WRITE_ONLY, VX_MEMORY_TYPE_HOST));
    }
    ~vxMatrix()
    {
        vxReleaseMatrix(&mtx);
    }
};

struct vxConvolution
{
    vx_convolution cnv;

    vxConvolution(vxContext &ctx, const short *data, int w, int h)
    {
        cnv = vxCreateConvolution(ctx.ctx, w, h);
        vxErr::check(cnv);
        vxErr::check(vxCopyConvolutionCoefficients(cnv, const_cast<short*>(data), VX_WRITE_ONLY, VX_MEMORY_TYPE_HOST));
    }
    ~vxConvolution()
    {
        vxReleaseConvolution(&cnv);
    }
};

//==================================================================================================
// real code starts here
// ...

#define OVX_BINARY_OP(hal_func, ovx_call)                                                                           \
template <typename T>                                                                                               \
inline int ovx_hal_##hal_func(const T *a, size_t astep, const T *b, size_t bstep, T *c, size_t cstep, int w, int h) \
{                                                                                                                   \
    try                                                                                                             \
    {                                                                                                               \
        vxContext * ctx = vxContext::getContext();                                                                  \
        vxImage ia(*ctx, a, astep, w, h);                                                                           \
        vxImage ib(*ctx, b, bstep, w, h);                                                                           \
        vxImage ic(*ctx, c, cstep, w, h);                                                                           \
        ovx_call                                                                                                    \
    }                                                                                                               \
    catch (vxErr & e)                                                                                               \
    {                                                                                                               \
        e.print();                                                                                                  \
        return CV_HAL_ERROR_UNKNOWN;                                                                                \
    }                                                                                                               \
    return CV_HAL_ERROR_OK;                                                                                         \
}

OVX_BINARY_OP(add, {vxErr::check(vxuAdd(ctx->ctx, ia.img, ib.img, VX_CONVERT_POLICY_SATURATE, ic.img));})
OVX_BINARY_OP(sub, {vxErr::check(vxuSubtract(ctx->ctx, ia.img, ib.img, VX_CONVERT_POLICY_SATURATE, ic.img));})

OVX_BINARY_OP(absdiff, {vxErr::check(vxuAbsDiff(ctx->ctx, ia.img, ib.img, ic.img));})

OVX_BINARY_OP(and, {vxErr::check(vxuAnd(ctx->ctx, ia.img, ib.img, ic.img));})
OVX_BINARY_OP(or, {vxErr::check(vxuOr(ctx->ctx, ia.img, ib.img, ic.img));})
OVX_BINARY_OP(xor, {vxErr::check(vxuXor(ctx->ctx, ia.img, ib.img, ic.img));})

template <typename T>
inline int ovx_hal_mul(const T *a, size_t astep, const T *b, size_t bstep, T *c, size_t cstep, int w, int h, double scale)
{
    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, w, h);
        vxImage ib(*ctx, b, bstep, w, h);
        vxImage ic(*ctx, c, cstep, w, h);
        vxErr::check(vxuMultiply(ctx->ctx, ia.img, ib.img, (float)scale, VX_CONVERT_POLICY_SATURATE, VX_ROUND_POLICY_TO_ZERO, ic.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_not(const uchar *a, size_t astep, uchar *c, size_t cstep, int w, int h)
{
    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, w, h);
        vxImage ic(*ctx, c, cstep, w, h);
        vxErr::check(vxuNot(ctx->ctx, ia.img, ic.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_merge8u(const uchar **src_data, uchar *dst_data, int len, int cn)
{
    if (cn != 3 && cn != 4)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, src_data[0], len, len, 1);
        vxImage ib(*ctx, src_data[1], len, len, 1);
        vxImage ic(*ctx, src_data[2], len, len, 1);
        vxImage id(*ctx, cn == 4 ? VX_DF_IMAGE_RGBX : VX_DF_IMAGE_RGB, dst_data, len, len, 1);
        vxErr::check(vxuChannelCombine(ctx->ctx, ia.img, ib.img, ic.img,
                                       cn == 4 ? vxImage(*ctx, src_data[3], len, len, 1).img : NULL,
                                       id.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}


#if defined OPENCV_IMGPROC_HAL_INTERFACE_H

inline int ovx_hal_resize(int atype, const uchar *a, size_t astep, int aw, int ah, uchar *b, size_t bstep, int bw, int bh, double inv_scale_x, double inv_scale_y, int interpolation)
{
    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, aw, ah);
        vxImage ib(*ctx, b, bstep, bw, bh);

        if(!((atype == CV_8UC1 || atype == CV_8SC1) &&
             inv_scale_x > 0 && inv_scale_y > 0 &&
             (bw - 0.5) / inv_scale_x - 0.5 < aw && (bh - 0.5) / inv_scale_y - 0.5 < ah &&
             (bw + 0.5) / inv_scale_x + 0.5 >= aw && (bh + 0.5) / inv_scale_y + 0.5 >= ah &&
             std::abs(bw / inv_scale_x - aw) < 0.1 && std::abs(bh / inv_scale_y - ah) < 0.1 ))
            return CV_HAL_ERROR_NOT_IMPLEMENTED;

        int mode;
        if (interpolation == CV_HAL_INTER_LINEAR)
            mode = VX_INTERPOLATION_BILINEAR;
        else if (interpolation == CV_HAL_INTER_AREA)
            mode = VX_INTERPOLATION_AREA;
        else if (interpolation == CV_HAL_INTER_NEAREST)
            mode = VX_INTERPOLATION_NEAREST_NEIGHBOR;
        else
            return CV_HAL_ERROR_NOT_IMPLEMENTED;

        vxErr::check( vxuScaleImage(ctx->ctx, ia.img, ib.img, mode));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_warpAffine(int atype, const uchar *a, size_t astep, int aw, int ah, uchar *b, size_t bstep, int bw, int bh, const double M[6], int interpolation, int borderType, const double borderValue[4])
{
    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, aw, ah);
        vxImage ib(*ctx, b, bstep, bw, bh);

        if (!(atype == CV_8UC1 || atype == CV_8SC1))
            return CV_HAL_ERROR_NOT_IMPLEMENTED;

        vx_border_t border;
        switch (borderType)
        {
        case CV_HAL_BORDER_CONSTANT:
            border.mode = VX_BORDER_CONSTANT;
            border.constant_value.U8 = (vx_uint8)(borderValue[0]);
            break;
        case CV_HAL_BORDER_REPLICATE:
            border.mode = VX_BORDER_REPLICATE;
            break;
        default:
            return CV_HAL_ERROR_NOT_IMPLEMENTED;
        }

        int mode;
        if (interpolation == CV_HAL_INTER_LINEAR)
            mode = VX_INTERPOLATION_BILINEAR;
        else if (interpolation == CV_HAL_INTER_AREA)
            mode = VX_INTERPOLATION_AREA;
        else if (interpolation == CV_HAL_INTER_NEAREST)
            mode = VX_INTERPOLATION_NEAREST_NEIGHBOR;
        else
            return CV_HAL_ERROR_NOT_IMPLEMENTED;

        std::vector<float> data;
        data.reserve(6);
        for (int j = 0; j < 3; ++j)
            for (int i = 0; i < 2; ++i)
                data.push_back((float)(M[i*3+j]));

        vxMatrix mtx(*ctx, data.data(), 2, 3);
        //ATTENTION: VX_CONTEXT_IMMEDIATE_BORDER attribute change could lead to strange issues in multi-threaded environments
        //since OpenVX standart says nothing about thread-safety for now
        vx_border_t prevBorder;
        vxErr::check(vxQueryContext(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &border, sizeof(border)));
        vxErr::check(vxuWarpAffine(ctx->ctx, ia.img, mtx.mtx, mode, ib.img));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_warpPerspectve(int atype, const uchar *a, size_t astep, int aw, int ah, uchar *b, size_t bstep, int bw, int bh, const double M[9], int interpolation, int borderType, const double borderValue[4])
{
    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, aw, ah);
        vxImage ib(*ctx, b, bstep, bw, bh);

        if (!(atype == CV_8UC1 || atype == CV_8SC1))
            return CV_HAL_ERROR_NOT_IMPLEMENTED;

        vx_border_t border;
        switch (borderType)
        {
        case CV_HAL_BORDER_CONSTANT:
            border.mode = VX_BORDER_CONSTANT;
            border.constant_value.U8 = (vx_uint8)(borderValue[0]);
            break;
        case CV_HAL_BORDER_REPLICATE:
            border.mode = VX_BORDER_REPLICATE;
            break;
        default:
            return CV_HAL_ERROR_NOT_IMPLEMENTED;
        }

        int mode;
        if (interpolation == CV_HAL_INTER_LINEAR)
            mode = VX_INTERPOLATION_BILINEAR;
        else if (interpolation == CV_HAL_INTER_AREA)
            mode = VX_INTERPOLATION_AREA;
        else if (interpolation == CV_HAL_INTER_NEAREST)
            mode = VX_INTERPOLATION_NEAREST_NEIGHBOR;
        else
            return CV_HAL_ERROR_NOT_IMPLEMENTED;

        std::vector<float> data;
        data.reserve(9);
        for (int j = 0; j < 3; ++j)
            for (int i = 0; i < 3; ++i)
                data.push_back((float)(M[i * 3 + j]));

        vxMatrix mtx(*ctx, data.data(), 3, 3);
        //ATTENTION: VX_CONTEXT_IMMEDIATE_BORDER attribute change could lead to strange issues in multi-threaded environments
        //since OpenVX standart says nothing about thread-safety for now
        vx_border_t prevBorder;
        vxErr::check(vxQueryContext(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &border, sizeof(border)));
        vxErr::check(vxuWarpPerspective(ctx->ctx, ia.img, mtx.mtx, mode, ib.img));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

struct cvhalFilter2D;

struct FilterCtx
{
    vxConvolution cnv;
    vx_border_t border;
    int dst_type;
    FilterCtx(vxContext &ctx, const short *data, int w, int h, int _dst_type, vx_border_t & _border) :
        cnv(ctx, data, w, h), dst_type(_dst_type), border(_border) {}
};

inline int ovx_hal_filterInit(cvhalFilter2D **filter_context, uchar *kernel_data, size_t kernel_step, int kernel_type, int kernel_width, int kernel_height,
    int , int , int src_type, int dst_type, int borderType, double delta, int anchor_x, int anchor_y, bool allowSubmatrix, bool allowInplace)
{
    if (!filter_context || !kernel_data || allowSubmatrix || allowInplace || delta != 0 ||
        src_type != CV_8UC1 || (dst_type != CV_8UC1 && dst_type != CV_16SC1) ||
        kernel_width % 2 == 0 || kernel_height % 2 == 0 || anchor_x != kernel_width / 2 || anchor_y != kernel_height / 2)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    vx_border_t border;
    switch (borderType)
    {
    case CV_HAL_BORDER_CONSTANT:
        border.mode = VX_BORDER_CONSTANT;
        border.constant_value.U8 = 0;
        break;
    case CV_HAL_BORDER_REPLICATE:
        border.mode = VX_BORDER_REPLICATE;
        break;
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }

    vxContext * ctx = vxContext::getContext();

    std::vector<short> data;
    data.reserve(kernel_width*kernel_height);
    switch (kernel_type)
    {
    case CV_8UC1:
        for (int j = 0; j < kernel_height; ++j)
        {
            uchar * row = (uchar*)(kernel_data + kernel_step*j);
            for (int i = 0; i < kernel_width; ++i)
                data.push_back(row[i]);
        }
        break;
    case CV_8SC1:
        for (int j = 0; j < kernel_height; ++j)
        {
            schar * row = (schar*)(kernel_data + kernel_step*j);
            for (int i = 0; i < kernel_width; ++i)
                data.push_back(row[i]);
        }
        break;
    case CV_16SC1:
        for (int j = 0; j < kernel_height; ++j)
        {
            short * row = (short*)(kernel_data + kernel_step*j);
            for (int i = 0; i < kernel_width; ++i)
                data.push_back(row[i]);
        }
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }

    FilterCtx* cnv = new FilterCtx(*ctx, data.data(), kernel_width, kernel_height, dst_type, border);
    if (!cnv)
        return CV_HAL_ERROR_UNKNOWN;

    *filter_context = (cvhalFilter2D*)(cnv);
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_filterFree(cvhalFilter2D *filter_context)
{
    if (filter_context)
    {
        delete (FilterCtx*)filter_context;
        return CV_HAL_ERROR_OK;
    }
    else
    {
        return CV_HAL_ERROR_UNKNOWN;
    }
}

inline int ovx_hal_filter(cvhalFilter2D *filter_context, uchar *a, size_t astep, uchar *b, size_t bstep, int w, int h, int , int , int , int )
{
    try
    {
        FilterCtx* cnv = (FilterCtx*)filter_context;
        if(!cnv)
            vxErr(VX_ERROR_INVALID_PARAMETERS, "Bad HAL context").check();

        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, w, h);

        //ATTENTION: VX_CONTEXT_IMMEDIATE_BORDER attribute change could lead to strange issues in multi-threaded environments
        //since OpenVX standart says nothing about thread-safety for now
        vx_border_t prevBorder;
        vxErr::check(vxQueryContext(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &(cnv->border), sizeof(cnv->border)));
        if (cnv->dst_type == CV_16SC1)
        {
            vxImage ib(*ctx, (short*)b, bstep, w, h);
            vxErr::check(vxuConvolve(ctx->ctx, ia.img, cnv->cnv.cnv, ib.img));
        }
        else
        {
            vxImage ib(*ctx, b, bstep, w, h);
            vxErr::check(vxuConvolve(ctx->ctx, ia.img, cnv->cnv.cnv, ib.img));
        }
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_sepFilterInit(cvhalFilter2D **filter_context, int src_type, int dst_type,
                                 int kernel_type, uchar *kernelx_data, int kernelx_length, uchar *kernely_data, int kernely_length,
                                 int anchor_x, int anchor_y, double delta, int borderType)
{
    if (!filter_context || !kernelx_data || !kernely_data || delta != 0 ||
        src_type != CV_8UC1 || (dst_type != CV_8UC1 && dst_type != CV_16SC1) ||
        kernelx_length % 2 == 0 || kernely_length % 2 == 0 || anchor_x != kernelx_length / 2 || anchor_y != kernely_length / 2)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    vx_border_t border;
    switch (borderType)
    {
    case CV_HAL_BORDER_CONSTANT:
        border.mode = VX_BORDER_CONSTANT;
        border.constant_value.U8 = 0;
        break;
    case CV_HAL_BORDER_REPLICATE:
        border.mode = VX_BORDER_REPLICATE;
        break;
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }

    vxContext * ctx = vxContext::getContext();

    //At the moment OpenVX doesn't support separable filters natively so combine kernels to generic convolution
    std::vector<short> data;
    data.reserve(kernelx_length*kernely_length);
    switch (kernel_type)
    {
    case CV_8UC1:
        for (int j = 0; j < kernely_length; ++j)
            for (int i = 0; i < kernelx_length; ++i)
                data.push_back((short)(kernely_data[j]) * kernelx_data[i]);
        break;
    case CV_8SC1:
        for (int j = 0; j < kernely_length; ++j)
            for (int i = 0; i < kernelx_length; ++i)
                data.push_back((short)(((schar*)kernely_data)[j]) * ((schar*)kernelx_data)[i]);
        break;
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }

    FilterCtx* cnv = new FilterCtx(*ctx, data.data(), kernelx_length, kernely_length, dst_type, border);
    if (!cnv)
        return CV_HAL_ERROR_UNKNOWN;

    *filter_context = (cvhalFilter2D*)(cnv);
    return CV_HAL_ERROR_OK;
}

struct MorphCtx
{
    vxMatrix mask;
    int operation;
    vx_border_t border;
    MorphCtx(vxContext &ctx, const uchar *data, int w, int h, int _operation, vx_border_t & _border) :
        mask(ctx, data, w, h), operation(_operation), border(_border) {}
};

inline int ovx_hal_morphInit(cvhalFilter2D **filter_context, int operation, int src_type, int dst_type, int , int ,
                             int kernel_type, uchar *kernel_data, size_t kernel_step, int kernel_width, int kernel_height, int anchor_x, int anchor_y,
                             int borderType, const double borderValue[4], int iterations, bool allowSubmatrix, bool allowInplace)
{
    if (!filter_context || !kernel_data || allowSubmatrix || allowInplace || iterations != 1 ||
        src_type != CV_8UC1 || dst_type != CV_8UC1 ||
        kernel_width % 2 == 0 || kernel_height % 2 == 0 || anchor_x != kernel_width / 2 || anchor_y != kernel_height / 2)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    vx_border_t border;
    switch (borderType)
    {
    case CV_HAL_BORDER_CONSTANT:
        border.mode = VX_BORDER_CONSTANT;
        if (borderValue[0] == DBL_MAX && borderValue[1] == DBL_MAX && borderValue[2] == DBL_MAX && borderValue[3] == DBL_MAX)
        {
            if (operation == MORPH_ERODE)
                border.constant_value.U8 = UCHAR_MAX;
            else
                border.constant_value.U8 = 0;
        }
        else
        {
            border.constant_value.U8 = cv::saturate_cast<uchar>(borderValue[0]);
        }
        break;
    case CV_HAL_BORDER_REPLICATE:
        border.mode = VX_BORDER_REPLICATE;
        break;
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }

    vxContext * ctx = vxContext::getContext();

    std::vector<uchar> kernel_mat;
    kernel_mat.resize(kernel_width * kernel_height);
    switch (CV_MAT_DEPTH(kernel_type))
    {
    case CV_8U:
    case CV_8S:
        for (int j = 0; j < kernel_height; ++j)
        {
            uchar * kernel_row = kernel_data + j * kernel_step;
            for (int i = 0; i < kernel_height; ++i)
                kernel_mat.push_back(kernel_row[i] ? 255 : 0);
        }
        break;
    case CV_16U:
    case CV_16S:
        for (int j = 0; j < kernel_height; ++j)
        {
            short * kernel_row = (short*)(kernel_data + j * kernel_step);
            for (int i = 0; i < kernel_height; ++i)
                kernel_mat.push_back(kernel_row[i] ? 255 : 0);
        }
        break;
    case CV_32S:
        for (int j = 0; j < kernel_height; ++j)
        {
            int * kernel_row = (int*)(kernel_data + j * kernel_step);
            for (int i = 0; i < kernel_height; ++i)
                kernel_mat.push_back(kernel_row[i] ? 255 : 0);
        }
        break;
    case CV_32F:
        for (int j = 0; j < kernel_height; ++j)
        {
            float * kernel_row = (float*)(kernel_data + j * kernel_step);
            for (int i = 0; i < kernel_height; ++i)
                kernel_mat.push_back(kernel_row[i] ? 255 : 0);
        }
        break;
    case CV_64F:
        for (int j = 0; j < kernel_height; ++j)
        {
            double * kernel_row = (double*)(kernel_data + j * kernel_step);
            for (int i = 0; i < kernel_height; ++i)
                kernel_mat.push_back(kernel_row[i] ? 255 : 0);
        }
        break;
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }

    MorphCtx* mat;
    switch (operation)
    {
    case MORPH_ERODE:
        mat = new MorphCtx(*ctx, kernel_mat.data(), kernel_width, kernel_height, VX_NONLINEAR_FILTER_MIN, border);
    case MORPH_DILATE:
        mat = new MorphCtx(*ctx, kernel_mat.data(), kernel_width, kernel_height, VX_NONLINEAR_FILTER_MAX, border);
        break;
    default:
        return CV_HAL_ERROR_NOT_IMPLEMENTED;
    }
    if (!mat)
        return CV_HAL_ERROR_UNKNOWN;

    *filter_context = (cvhalFilter2D*)(mat);
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_morphFree(cvhalFilter2D *filter_context)
{
    if (filter_context)
    {
        delete (MorphCtx*)filter_context;
        return CV_HAL_ERROR_OK;
    }
    else
    {
        return CV_HAL_ERROR_UNKNOWN;
    }
}

inline int ovx_hal_morph(cvhalFilter2D *filter_context, uchar *a, size_t astep, uchar *b, size_t bstep, int w, int h, int , int , int , int , int , int , int , int )
{
    try
    {
        MorphCtx* mat = (MorphCtx*)filter_context;
        if (!mat)
            vxErr(VX_ERROR_INVALID_PARAMETERS, "Bad HAL context").check();

        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, a, astep, w, h);
        vxImage ib(*ctx, b, bstep, w, h);

        //ATTENTION: VX_CONTEXT_IMMEDIATE_BORDER attribute change could lead to strange issues in multi-threaded environments
        //since OpenVX standart says nothing about thread-safety for now
        vx_border_t prevBorder;
        vxErr::check(vxQueryContext(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &(mat->border), sizeof(mat->border)));
        vxErr::check(vxuNonLinearFilter(ctx->ctx, mat->operation, ia.img, mat->mask.mtx, ib.img));
        vxErr::check(vxSetContextAttribute(ctx->ctx, VX_CONTEXT_IMMEDIATE_BORDER, &prevBorder, sizeof(prevBorder)));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_cvtBGRtoBGR(const uchar * a, size_t astep, uchar * b, size_t bstep, int w, int h, int depth, int acn, int bcn, bool swapBlue)
{
    if (depth != CV_8U || swapBlue || acn == bcn || (acn != 3 && acn != 4) || (bcn != 3 && bcn != 4))
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, acn == 3 ? VX_DF_IMAGE_RGB : VX_DF_IMAGE_RGBX, a, astep, w, h);
        vxImage ib(*ctx, bcn == 3 ? VX_DF_IMAGE_RGB : VX_DF_IMAGE_RGBX, b, bstep, w, h);
        vxErr::check(vxuColorConvert(ctx->ctx, ia.img, ib.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_cvtTwoPlaneYUVtoBGR(const uchar * a, size_t astep, uchar * b, size_t bstep, int w, int h, int bcn, bool swapBlue, int uIdx)
{
    if (!swapBlue || (bcn != 3 && bcn != 4))
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, uIdx ? VX_DF_IMAGE_NV21 : VX_DF_IMAGE_NV12, a, astep, w, h);
        vxImage ib(*ctx, bcn == 3 ? VX_DF_IMAGE_RGB : VX_DF_IMAGE_RGBX, b, bstep, w, h);
        vxErr::check(vxuColorConvert(ctx->ctx, ia.img, ib.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_cvtThreePlaneYUVtoBGR(const uchar * a, size_t astep, uchar * b, size_t bstep, int w, int h, int bcn, bool swapBlue, int uIdx)
{
    if (!swapBlue || (bcn != 3 && bcn != 4) || uIdx)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, VX_DF_IMAGE_IYUV, a, astep, w, h);
        vxImage ib(*ctx, bcn == 3 ? VX_DF_IMAGE_RGB : VX_DF_IMAGE_RGBX, b, bstep, w, h);
        vxErr::check(vxuColorConvert(ctx->ctx, ia.img, ib.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_cvtBGRtoThreePlaneYUV(const uchar * a, size_t astep, uchar * b, size_t bstep, int w, int h, int acn, bool swapBlue, int uIdx)
{
    if (!swapBlue || (acn != 3 && acn != 4) || uIdx)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, acn == 3 ? VX_DF_IMAGE_RGB : VX_DF_IMAGE_RGBX, a, astep, w, h);
        vxImage ib(*ctx, VX_DF_IMAGE_IYUV, b, bstep, w, h);
        vxErr::check(vxuColorConvert(ctx->ctx, ia.img, ib.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

inline int ovx_hal_cvtOnePlaneYUVtoBGR(const uchar * a, size_t astep, uchar * b, size_t bstep, int w, int h, int bcn, bool swapBlue, int uIdx, int ycn)
{
    if (!swapBlue || (bcn != 3 && bcn != 4) || uIdx)
        return CV_HAL_ERROR_NOT_IMPLEMENTED;

    try
    {
        vxContext * ctx = vxContext::getContext();
        vxImage ia(*ctx, ycn ? VX_DF_IMAGE_UYVY : VX_DF_IMAGE_YUYV, a, astep, w, h);
        vxImage ib(*ctx, bcn == 3 ? VX_DF_IMAGE_RGB : VX_DF_IMAGE_RGBX, b, bstep, w, h);
        vxErr::check(vxuColorConvert(ctx->ctx, ia.img, ib.img));
    }
    catch (vxErr & e)
    {
        e.print();
        return CV_HAL_ERROR_UNKNOWN;
    }
    return CV_HAL_ERROR_OK;
}

#endif

//==================================================================================================
// functions redefinition
// ...

#undef cv_hal_add8u
#define cv_hal_add8u ovx_hal_add<uchar>
#undef cv_hal_add16s
#define cv_hal_add16s ovx_hal_add<short>
#undef cv_hal_sub8u
#define cv_hal_sub8u ovx_hal_sub<uchar>
#undef cv_hal_sub16s
#define cv_hal_sub16s ovx_hal_sub<short>

#undef cv_hal_absdiff8u
#define cv_hal_absdiff8u ovx_hal_absdiff<uchar>
#undef cv_hal_absdiff16s
#define cv_hal_absdiff16s ovx_hal_absdiff<short>

#undef cv_hal_and8u
#define cv_hal_and8u ovx_hal_and<uchar>
#undef cv_hal_or8u
#define cv_hal_or8u ovx_hal_or<uchar>
#undef cv_hal_xor8u
#define cv_hal_xor8u ovx_hal_xor<uchar>
#undef cv_hal_not8u
#define cv_hal_not8u ovx_hal_not

#undef cv_hal_mul8u
#define cv_hal_mul8u ovx_hal_mul<uchar>
#undef cv_hal_mul16s
#define cv_hal_mul16s ovx_hal_mul<short>

#undef cv_hal_merge8u
#define cv_hal_merge8u ovx_hal_merge8u

#if defined OPENCV_IMGPROC_HAL_INTERFACE_H

#undef cv_hal_resize
#define cv_hal_resize ovx_hal_resize
#undef cv_hal_warpAffine
#define cv_hal_warpAffine ovx_hal_warpAffine
#undef cv_hal_warpPerspective
#define cv_hal_warpPerspective ovx_hal_warpPerspectve

#undef cv_hal_filterInit
#define cv_hal_filterInit ovx_hal_filterInit
#undef cv_hal_filter
#define cv_hal_filter ovx_hal_filter
#undef cv_hal_filterFree
#define cv_hal_filterFree ovx_hal_filterFree

#undef cv_hal_sepFilterInit
#define cv_hal_sepFilterInit ovx_hal_sepFilterInit
#undef cv_hal_sepFilter
#define cv_hal_sepFilter ovx_hal_filter
#undef cv_hal_sepFilterFree
#define cv_hal_sepFilterFree ovx_hal_filterFree

#undef cv_hal_morphInit
#define cv_hal_morphInit ovx_hal_morphInit
#undef cv_hal_morph
#define cv_hal_morph ovx_hal_morph
#undef cv_hal_morphFree
#define cv_hal_morphFree ovx_hal_morphFree

#undef cv_hal_cvtBGRtoBGR
#define cv_hal_cvtBGRtoBGR ovx_hal_cvtBGRtoBGR
#undef cv_hal_cvtTwoPlaneYUVtoBGR
#define cv_hal_cvtTwoPlaneYUVtoBGR ovx_hal_cvtTwoPlaneYUVtoBGR
#undef cv_hal_cvtThreePlaneYUVtoBGR
#define cv_hal_cvtThreePlaneYUVtoBGR ovx_hal_cvtThreePlaneYUVtoBGR
#undef cv_hal_cvtBGRtoThreePlaneYUV
#define cv_hal_cvtBGRtoThreePlaneYUV ovx_hal_cvtBGRtoThreePlaneYUV
#undef cv_hal_cvtOnePlaneYUVtoBGR
#define cv_hal_cvtOnePlaneYUVtoBGR ovx_hal_cvtOnePlaneYUVtoBGR

#endif

#endif