static bool ocl_minMaxIdx()

in modules/core/src/stat.cpp [2073:2208]

• 111 lines of code
• 55 McCabe index (conditional complexity)

static bool ocl_minMaxIdx( InputArray _src, double* minVal, double* maxVal, int* minLoc, int* maxLoc, InputArray _mask,
                           int ddepth = -1, bool absValues = false, InputArray _src2 = noArray(), double * maxVal2 = NULL)
{
    const ocl::Device & dev = ocl::Device::getDefault();

#ifdef ANDROID
    if (dev.isNVidia())
        return false;
#endif

    bool doubleSupport = dev.doubleFPConfig() > 0, haveMask = !_mask.empty(),
        haveSrc2 = _src2.kind() != _InputArray::NONE;
    int type = _src.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type),
            kercn = haveMask ? cn : std::min(4, ocl::predictOptimalVectorWidth(_src, _src2));

    // disabled following modes since it occasionally fails on AMD devices (e.g. A10-6800K, sep. 2014)
    if ((haveMask || type == CV_32FC1) && dev.isAMD())
        return false;

    CV_Assert( (cn == 1 && (!haveMask || _mask.type() == CV_8U)) ||
              (cn >= 1 && !minLoc && !maxLoc) );

    if (ddepth < 0)
        ddepth = depth;

    CV_Assert(!haveSrc2 || _src2.type() == type);

    if (depth == CV_32S)
        return false;

    if ((depth == CV_64F || ddepth == CV_64F) && !doubleSupport)
        return false;

    int groupnum = dev.maxComputeUnits();
    size_t wgs = dev.maxWorkGroupSize();

    int wgs2_aligned = 1;
    while (wgs2_aligned < (int)wgs)
        wgs2_aligned <<= 1;
    wgs2_aligned >>= 1;

    bool needMinVal = minVal || minLoc, needMinLoc = minLoc != NULL,
            needMaxVal = maxVal || maxLoc, needMaxLoc = maxLoc != NULL;

    // in case of mask we must know whether mask is filled with zeros or not
    // so let's calculate min or max location, if it's undefined, so mask is zeros
    if (!(needMaxLoc || needMinLoc) && haveMask)
    {
        if (needMinVal)
            needMinLoc = true;
        else
            needMaxLoc = true;
    }

    char cvt[2][40];
    String opts = format("-D DEPTH_%d -D srcT1=%s%s -D WGS=%d -D srcT=%s"
                         " -D WGS2_ALIGNED=%d%s%s%s -D kercn=%d%s%s%s%s"
                         " -D dstT1=%s -D dstT=%s -D convertToDT=%s%s%s%s%s -D wdepth=%d -D convertFromU=%s"
                         " -D MINMAX_STRUCT_ALIGNMENT=%d",
                         depth, ocl::typeToStr(depth), haveMask ? " -D HAVE_MASK" : "", (int)wgs,
                         ocl::typeToStr(CV_MAKE_TYPE(depth, kercn)), wgs2_aligned,
                         doubleSupport ? " -D DOUBLE_SUPPORT" : "",
                         _src.isContinuous() ? " -D HAVE_SRC_CONT" : "",
                         _mask.isContinuous() ? " -D HAVE_MASK_CONT" : "", kercn,
                         needMinVal ? " -D NEED_MINVAL" : "", needMaxVal ? " -D NEED_MAXVAL" : "",
                         needMinLoc ? " -D NEED_MINLOC" : "", needMaxLoc ? " -D NEED_MAXLOC" : "",
                         ocl::typeToStr(ddepth), ocl::typeToStr(CV_MAKE_TYPE(ddepth, kercn)),
                         ocl::convertTypeStr(depth, ddepth, kercn, cvt[0]),
                         absValues ? " -D OP_ABS" : "",
                         haveSrc2 ? " -D HAVE_SRC2" : "", maxVal2 ? " -D OP_CALC2" : "",
                         haveSrc2 && _src2.isContinuous() ? " -D HAVE_SRC2_CONT" : "", ddepth,
                         depth <= CV_32S && ddepth == CV_32S ? ocl::convertTypeStr(CV_8U, ddepth, kercn, cvt[1]) : "noconvert",
                         MINMAX_STRUCT_ALIGNMENT);

    ocl::Kernel k("minmaxloc", ocl::core::minmaxloc_oclsrc, opts);
    if (k.empty())
        return false;

    int esz = CV_ELEM_SIZE(ddepth), esz32s = CV_ELEM_SIZE1(CV_32S),
            dbsize = groupnum * ((needMinVal ? esz : 0) + (needMaxVal ? esz : 0) +
                                 (needMinLoc ? esz32s : 0) + (needMaxLoc ? esz32s : 0) +
                                 (maxVal2 ? esz : 0))
                     + 5 * MINMAX_STRUCT_ALIGNMENT;
    UMat src = _src.getUMat(), src2 = _src2.getUMat(), db(1, dbsize, CV_8UC1), mask = _mask.getUMat();

    if (cn > 1 && !haveMask)
    {
        src = src.reshape(1);
        src2 = src2.reshape(1);
    }

    if (haveSrc2)
    {
        if (!haveMask)
            k.args(ocl::KernelArg::ReadOnlyNoSize(src), src.cols, (int)src.total(),
                   groupnum, ocl::KernelArg::PtrWriteOnly(db), ocl::KernelArg::ReadOnlyNoSize(src2));
        else
            k.args(ocl::KernelArg::ReadOnlyNoSize(src), src.cols, (int)src.total(),
                   groupnum, ocl::KernelArg::PtrWriteOnly(db), ocl::KernelArg::ReadOnlyNoSize(mask),
                   ocl::KernelArg::ReadOnlyNoSize(src2));
    }
    else
    {
        if (!haveMask)
            k.args(ocl::KernelArg::ReadOnlyNoSize(src), src.cols, (int)src.total(),
                   groupnum, ocl::KernelArg::PtrWriteOnly(db));
        else
            k.args(ocl::KernelArg::ReadOnlyNoSize(src), src.cols, (int)src.total(),
                   groupnum, ocl::KernelArg::PtrWriteOnly(db), ocl::KernelArg::ReadOnlyNoSize(mask));
    }

    size_t globalsize = groupnum * wgs;
    if (!k.run(1, &globalsize, &wgs, true))
        return false;

    static const getMinMaxResFunc functab[7] =
    {
        getMinMaxRes<uchar>,
        getMinMaxRes<char>,
        getMinMaxRes<ushort>,
        getMinMaxRes<short>,
        getMinMaxRes<int>,
        getMinMaxRes<float>,
        getMinMaxRes<double>
    };

    getMinMaxResFunc func = functab[ddepth];

    int locTemp[2];
    func(db.getMat(ACCESS_READ), minVal, maxVal,
         needMinLoc ? minLoc ? minLoc : locTemp : minLoc,
         needMaxLoc ? maxLoc ? maxLoc : locTemp : maxLoc,
         groupnum, src.cols, maxVal2);

    return true;
}