convolution_layer.cpp 56.6 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
// This file is part of OpenCV project.
// It is subject to the license terms in the LICENSE file found in the top-level directory
// of this distribution and at http://opencv.org/license.html.

#include "../precomp.hpp"
#include "layers_common.hpp"

#include <opencv2/core/utils/logger.hpp>

#include "opencv2/core/hal/hal.hpp"
#include "opencv2/core/hal/intrin.hpp"
#include <iostream>
#include <numeric>

namespace cv
{
namespace dnn
{

#if CV_SIMD
static inline void v_expand_mul_add(const v_int8x16& a, const v_int8x16& b,
                                    v_int32x4& out0, v_int32x4& out1, v_int32x4& out2, v_int32x4& out3)
{
    v_int16x8 a0, a1, b0, b1;
    v_expand(a, a0, a1);
    v_expand(b, b0, b1);

    v_int32x4 t0, t1;
    v_mul_expand(a0, b0, t0, t1);
    out0 += t0; out1 += t1;

    v_mul_expand(a1, b1, t0, t1);
    out2 += t0; out3 += t1;
}
#endif

class BaseConvolutionLayerInt8Impl : public ConvolutionLayerInt8
{
public:
    BaseConvolutionLayerInt8Impl(const LayerParams &params)
    {
        setParamsFrom(params);
        getConvolutionKernelParams(params, kernel_size, pads_begin, pads_end, strides, dilations, padMode, adjust_pads);

        numOutput = params.get<int>("num_output");
        int ngroups = params.get<int>("group", 1);
        CV_Assert(numOutput % ngroups == 0);

        input_zp = params.get<int>("input_zeropoint");
        output_zp = params.get<int>("zeropoints");
        output_sc = params.get<float>("scales");

        if (kernel_size.size() == 2) {
            kernel = Size(kernel_size[1], kernel_size[0]);
            stride = Size(strides[1], strides[0]);
            for (int i = 0; i < pads_begin.size(); i++) {
                if (pads_begin[i] != pads_end[i])
                    CV_Error(Error::StsNotImplemented, "Unsupported asymmetric padding in convolution layer");
            }
            pad = Size(pads_begin[1], pads_begin[0]);
            dilation = Size(dilations[1], dilations[0]);

            adjustPad.height = adjust_pads[0];
            adjustPad.width = adjust_pads[1];
        }

        for (int i = 0; i < adjust_pads.size(); i++) {
            CV_Assert(adjust_pads[i] < strides[i]);
        }
    }

    virtual void finalize(InputArrayOfArrays inputs_arr, OutputArrayOfArrays outputs_arr) CV_OVERRIDE
    {
        std::vector<Mat> inputs, outputs;
        inputs_arr.getMatVector(inputs);
        outputs_arr.getMatVector(outputs);

        // blobs[0] - Weights (INT8)
        // blobs[1] - Biases (INT32)
        // blobs[2] - Multipliers for convolution output stage (FP32)
        CV_Assert(!inputs.empty() && blobs.size() == 3);
        MatSize weightShape = blobs[0].size;

        CV_Assert(inputs[0].dims == outputs[0].dims);
        if (weightShape.dims() == 3)
        {
            kernel_size.assign(1, kernel_size[0]);
            strides.assign(1, strides[0]);
            dilations.assign(1, dilations[0]);
            pads_begin.assign(1, pads_begin[0]);
            pads_end.assign(1, pads_end[0]);
        }
        CV_Assert(weightShape.dims() == kernel_size.size() + 2);
        for (int i = 0; i < kernel_size.size(); i++) {
            CV_Assert(weightShape[i + 2] == kernel_size[i]);
        }

        const Mat &input = inputs[0];
        CV_Assert(((input.dims == 3 && kernel_size.size() == 1) || input.dims == 4 || input.dims == 5) && input.type() == CV_8S);
        for (size_t i = 0; i < outputs.size(); i++)
        {
            CV_Assert(inputs[i].type() == input.type());
            CV_Assert(((input.dims == 3 && kernel_size.size() == 1) || inputs[i].dims == 4 || inputs[i].dims == 5) && inputs[i].size[1] == input.size[1]);
            for (int j = 0; j < inputs[i].dims; j++) {
                CV_Assert(inputs[i].size[j] == input.size[j]);
            }
        }

        std::vector<int> inpShape;
        std::vector<int> outShape;
        for (int i = 2; i < inputs[0].dims; i++) {
            inpShape.push_back(inputs[0].size[i]);
            outShape.push_back(outputs[0].size[i]);
        }
        getConvPoolPaddings(inpShape, kernel_size, strides, padMode, pads_begin, pads_end);
        if (pads_begin.size() == 2) {
            for (int i = 0; i < pads_begin.size(); i++) {
                if (pads_begin[i] != pads_end[i])
                    CV_Error(Error::StsNotImplemented, "Unsupported asymmetric padding in convolution layer");
            }
            pad = Size(pads_begin[1], pads_begin[0]);
        }
    }

    virtual MatShape computeColRowShape(const MatShape &inpShape, const MatShape &outShape) const = 0;
    bool is1x1() const
    {
        return (kernel.height == 1 && kernel.width == 1) &&
               (stride.height == 1 && stride.width == 1) &&
               (dilation.height == 1 && dilation.width == 1);
    }

    virtual bool tryFuse(Ptr<Layer>& top) CV_OVERRIDE
    {
        Mat w, b;
        top->getScaleShift(w, b);
        if (w.empty() && b.empty())
            return false;

        CV_Assert((w.empty() || w.type() == CV_32F) &&
                  (b.empty() || b.type() == CV_32F));

        float new_sc;
        int new_zp;
        top->getScaleZeropoint(new_sc, new_zp);
        fuseWeights(w, b, new_sc);
        output_sc = new_sc;
        output_zp = new_zp;
        return true;
    }

    virtual void fuseWeights(const Mat& w_, const Mat& b_, const float& new_sc) = 0;
};

//TODO: simultaneously convolution and bias addition for cache optimization
class ConvolutionLayerInt8Impl CV_FINAL : public BaseConvolutionLayerInt8Impl
{
public:
    enum { VEC_ALIGN = 32, DFT_TYPE = CV_8S };
    Mat weightsMat;
    std::vector<int> biasvec;
    std::vector<float> outputMultiplier;
    Mat activationLUT;
    Ptr<ActivationLayerInt8> activ;

    ConvolutionLayerInt8Impl(const LayerParams &params) : BaseConvolutionLayerInt8Impl(params){}

    MatShape computeColRowShape(const MatShape &inpShape, const MatShape &outShape) const CV_OVERRIDE
    {
        CV_Assert(!blobs.empty());
        int dims = inpShape.size();
        int inpD = dims == 5 ? inpShape[2] : 1;
        int inpH = inpShape[dims - 2];
        int inpW = inpShape.back();
        int inpGroupCn = blobs[0].size[1];
        int ksize = inpGroupCn * std::accumulate(kernel_size.begin(), kernel_size.end(),
                                                 1, std::multiplies<size_t>());
        return shape(inpD * inpH * inpW, ksize);
    }

    virtual bool supportBackend(int backendId) CV_OVERRIDE
    {
        size_t ksize = kernel_size.size();
        // Only default backend and Conv1D/Conv2D/Conv3D are supported
        return backendId == DNN_BACKEND_OPENCV && ksize >= 1 && ksize <= 3;
    }

    bool getMemoryShapes(const std::vector<MatShape> &inputs,
                         const int requiredOutputs,
                         std::vector<MatShape> &outputs,
                         std::vector<MatShape> &internals) const CV_OVERRIDE
    {
        CV_Assert(!blobs.empty());
        const int* weightShape = blobs[0].size.p;
        CV_Assert(blobs[1].total() == (size_t)weightShape[0]);

        internals.clear();

        CV_Assert(inputs.size() != 0);
        std::vector<int> inpShape(inputs[0].begin() + 2, inputs[0].end());

        int outCn = weightShape[0];
        std::vector<int> outShape;
        outShape.push_back(inputs[0][0]);
        outShape.push_back(outCn);

        int inpCn = inputs[0][1];
        if (padMode.empty())
        {
            for (int i = 0; i < inpShape.size(); i++)
                outShape.push_back((inpShape[i] + pads_begin[i] + pads_end[i] - dilations[i] * (kernel_size[i] - 1) - 1) / strides[i] + 1);
        }
        else
        {
            getConvPoolOutParams(inpShape, kernel_size, strides, padMode, dilations, outShape);
        }

        int ngroups = inpCn / weightShape[1];
        if (ngroups == 0 || ngroups * weightShape[1] != inpCn)
            CV_Error(Error::StsError, format("Number of input channels should "
                     "be multiple of %d but got %d", weightShape[1], inpCn));
        CV_Assert(ngroups > 0 && inpCn % ngroups == 0 && outCn % ngroups == 0);

        outputs.resize(1, outShape);

        return false;
    }

    virtual void finalize(InputArrayOfArrays inputs_arr, OutputArrayOfArrays outputs_arr) CV_OVERRIDE
    {
        BaseConvolutionLayerInt8Impl::finalize(inputs_arr, outputs_arr);

        std::vector<Mat> inputs;
        inputs_arr.getMatVector(inputs);
        // prepare weightsMat where each row is aligned and has enough zero padding on the right to
        // use vectorized (i.e. with intrinsics) loops without tail processing
        Mat wm = blobs[0].reshape(1, numOutput);
        if( wm.step1() % VEC_ALIGN != 0 )
        {
            int newcols = (int)alignSize(wm.step1(), VEC_ALIGN);
            Mat wm_buffer = Mat(numOutput, newcols, wm.type());
            Mat wm_padding = wm_buffer.colRange(wm.cols, newcols);
            wm_padding.setTo(Scalar::all(0));
            Mat wm_aligned = wm_buffer.colRange(0, wm.cols);
            wm.copyTo(wm_aligned);
            wm = wm_aligned;
        }
        weightsMat = wm;

        Mat biasMat = blobs[1];
        biasvec.resize(numOutput+2);

        Mat outMult = blobs[2];
        outputMultiplier.resize(numOutput+2);
        for(int i = 0; i < numOutput; i++ )
        {
            biasvec[i] = biasMat.at<int>(i);
            outputMultiplier[i] = outMult.at<float>(i);
        }
    }

    bool setActivation(const Ptr<ActivationLayer>& layer) CV_OVERRIDE
    {
        Ptr<ActivationLayerInt8> activ_int8 = layer.dynamicCast<ActivationLayerInt8>();
        if (!activ_int8.empty())
        {
            activ = activ_int8;
            if (!activ_int8->blobs.empty())
                activ_int8->blobs[0].convertTo(activationLUT, CV_32S);
            return true;
        }
        return false;
    }

    virtual bool tryFuse(Ptr<Layer>& top) CV_OVERRIDE
    {
        return BaseConvolutionLayerInt8Impl::tryFuse(top);
    }

    void fuseWeights(const Mat& w_, const Mat& b_, const float& new_sc) CV_OVERRIDE
    {
        const int outCn = weightsMat.size[0];
        Mat w = w_.total() == 1 ? Mat(1, outCn, CV_32F, Scalar(w_.at<float>(0))) : w_;
        Mat b = b_.total() == 1 ? Mat(1, outCn, CV_32F, Scalar(b_.at<float>(0))) : b_;
        CV_Assert_N(!weightsMat.empty(), biasvec.size() == outCn + 2,
                    w.empty() || outCn == w.total(), b.empty() || outCn == b.total());

        for (int i = 0; i < outCn; ++i)
        {
            float off = outputMultiplier[i] * output_sc;
            if (!w.empty())
                off *= w.at<float>(i);

            if (!b.empty())
                biasvec[i] += (int)std::round(b.at<float>(i)/off);

            outputMultiplier[i] = off/new_sc;
        }
        biasvec[outCn] = biasvec[outCn+1] = biasvec[outCn-1];
        outputMultiplier[outCn] = outputMultiplier[outCn+1] = outputMultiplier[outCn-1];
    }

    class ParallelConv : public cv::ParallelLoopBody
    {
    public:
        enum { BLK_SIZE = 32, BLK_SIZE_CN = 64 };

        const Mat* input_;
        const Mat* weights_;
        Mat* output_;
        int outShape[4]; // used only for conv2d
        std::vector<size_t> kernel_size, pads_begin, pads_end, strides, dilations;
        int ngroups_, nstripes_;
        std::vector<int> ofstab_;
        const std::vector<int>* biasvec_;
        const Mat* activLUT_;
        const ActivationLayerInt8* activ_;
        bool is1x1_;
        bool useAVX2;
        bool useAVX512;
        int blk_size_cn;
        int inpZp, outZp;
        const std::vector<float>* multiplier;

        ParallelConv()
            : input_(0), weights_(0), output_(0), ngroups_(0), nstripes_(0),
              biasvec_(0), activLUT_(0), activ_(0), is1x1_(false), useAVX2(false), useAVX512(false)
            , blk_size_cn(0), inpZp(0), outZp(0), multiplier(0)
        {}

        static void run( const Mat& input, Mat& output, const Mat& weights, const std::vector<float>& multipliers,
                         const std::vector<int>& biasvec, const Mat& activLUT,
                         const std::vector<size_t>& kernel_size, const std::vector<size_t>& strides,
                         const std::vector<size_t>& pads_begin, const std::vector<size_t>& pads_end,
                         const std::vector<size_t>& dilations,
                         const ActivationLayerInt8* activ, int ngroups, int nstripes, int inp_Zp, int out_Zp)
        {
            size_t karea = std::accumulate(kernel_size.begin(), kernel_size.end(),
                                           1, std::multiplies<size_t>());
            bool isConv1D = input.dims == 3;
            bool isConv2D = input.dims == 4;
            bool isConv3D = input.dims == 5;
            CV_CheckEQ(static_cast<int>(kernel_size.size()), input.dims - 2, "");
            CV_Assert_N(input.dims == output.dims,
                       input.size[0] == output.size[0],
                       weights.rows == output.size[1],
                       weights.cols == (input.size[1]/ngroups)*karea,
                       input.type() == CV_8SC1,
                       output.type() == CV_32SC1,
                       input.type() == weights.type(),
                       input.isContinuous(),
                       output.isContinuous(),
                       biasvec.size() == (size_t)output.size[1]+2);
            CV_Check(weights.step1(), weights.step1() % VEC_ALIGN == 0, "");
            ParallelConv p;

            p.input_ = &input;
            p.weights_ = &weights;
            p.output_ = &output;
            int max_ind = isConv1D? 3: 4;
            for( int i = 0; i < max_ind; i++ ) p.outShape[i] = output.size[i];
            p.outShape[1] /= ngroups;

            p.kernel_size = kernel_size; p.strides = strides; p.dilations = dilations;
            p.pads_begin = pads_begin; p.pads_end = pads_end;

            p.ngroups_ = ngroups;
            p.nstripes_ = nstripes;

            int inpCnAll = input.size[1];
            int depth = (input.dims == 5) ? input.size[2] : 1;
            int width = input.size[input.dims - 1];
            int height = isConv1D? 1 : input.size[input.dims - 2];
            int inpCn = inpCnAll / ngroups;

            p.is1x1_ = (isConv2D && kernel_size[0] == 1 && kernel_size[1] == 1 &&
                       pads_begin[0] == 0  && pads_begin[1] == 0) ||
                       (isConv1D && pads_begin[0] == 0 && kernel_size[0] == 1);

            p.useAVX2   = checkHardwareSupport(CPU_AVX2) && isConv2D;
            p.useAVX512 = CV_CPU_HAS_SUPPORT_AVX512_SKX  && isConv2D;

            int kernel_d = isConv3D? kernel_size[0] : 1;
            int kernel_h = isConv1D? 1 : kernel_size[kernel_size.size() - 2];
            int kernel_w = kernel_size.back();

            int blk_size_cn0 = cvCeil(1600./(kernel_w*kernel_h));
            int ncn = 32;
            while (ncn*2 < blk_size_cn0 && ncn < inpCn)
                ncn *= 2;
            ncn = std::min(ncn, inpCn);
            p.blk_size_cn = ncn;

            int dil_d = isConv3D? dilations[0] : 1;
            int dil_h = isConv1D? 1 : dilations[dilations.size() - 2];
            int dil_w = dilations.back();

            p.inpZp = inp_Zp;
            p.outZp = out_Zp;
            p.multiplier = &multipliers;

            p.ofstab_.resize(karea * ncn);
            int* ofstab = &p.ofstab_[0];

            if (isConv1D)
            {
                for( int k = 0; k < ncn; k++ )
                    for( int k_c = 0; k_c < kernel_w; k_c++ )
                        ofstab[k*kernel_w + k_c] = k*width + k_c*dil_w;
            }
            else if (isConv2D)
            {
                for( int k = 0; k < ncn; k++ )
                    for( int k_r = 0; k_r < kernel_h; k_r++ )
                        for( int k_c = 0; k_c < kernel_w; k_c++ )
                            ofstab[(k*kernel_h + k_r)*kernel_w + k_c] =
                                   (k*height + k_r*dil_h)*width + k_c*dil_w;
            }
            else
            {
                for( int k = 0; k < ncn; k++ )
                    for (int k_d = 0; k_d < kernel_d; k_d++)
                        for( int k_r = 0; k_r < kernel_h; k_r++ )
                            for( int k_c = 0; k_c < kernel_w; k_c++ )
                                ofstab[(k*kernel_d*kernel_h + k_d*kernel_h + k_r)*kernel_w + k_c] =
                                       (k*depth*height + k_d*dil_d*height + k_r*dil_h)*width + k_c*dil_w;
            }

            p.biasvec_ = &biasvec;
            p.activLUT_ = &activLUT;
            p.activ_ = !activLUT.empty() ? activ : 0;

            parallel_for_(Range(0, nstripes), p, nstripes);
        }

        virtual void operator ()(const Range &r0) const CV_OVERRIDE
        {
            const int valign = ConvolutionLayerInt8Impl::VEC_ALIGN;
            int ngroups = ngroups_, batchSize = input_->size[0]*ngroups;
            bool isConv1D = input_->dims == 3;
            bool isConv2D = input_->dims == 4;
            bool isConv3D = input_->dims == 5;

            int outW = output_->size[output_->dims - 1];
            int outH = isConv1D? 1 : output_->size[output_->dims - 2];
            int outCn = output_->size[1]/ngroups;

            int depth = isConv3D? input_->size[2] : 1;
            int height = isConv1D? 1 : input_->size[input_->dims - 2];
            int width = input_->size[input_->dims - 1];
            int inpCn = input_->size[1]/ngroups;

            const int nstripes = nstripes_;

            int kernel_d = isConv3D? kernel_size[0] : 1;
            int kernel_h = isConv1D? 1 : kernel_size[kernel_size.size() - 2];
            int kernel_w = kernel_size.back();
            int karea = kernel_w*kernel_h*kernel_d;

            int pad_d = isConv3D? pads_begin[0] : 0;
            int pad_t = isConv1D? 0 : pads_begin[pads_begin.size() - 2];
            int pad_l = pads_begin.back();

            int stride_d = isConv3D? strides[0] : 0;
            int stride_h = isConv1D? 0 : strides[strides.size() - 2];
            int stride_w = strides.back();

            int dilation_d = isConv3D? dilations[0] : 1;
            int dilation_h = isConv1D? 1 : dilations[dilations.size() - 2];
            int dilation_w = dilations.back();

            int i, j, k, d;
            int inpPlaneSize = (int)input_->total(2);
            int outPlaneSize = (int)output_->total(2);
            bool is1x1 = is1x1_;

            int stripesPerSample;
            int stripeSize;
            Range r = r0;
            bool depthWiseConvolution = !is1x1 && isConv2D && ngroups > 1 && inpCn == 1 &&
                outCn == 1 && kernel_d == 1 && dilation_d == 1 && stride_d == 0 && pad_d == 0 &&
                width >= 16 + dilation_w*(kernel_w - 1);
            // for now only 3x3 depth-wise convolutions are supported
            depthWiseConvolution = depthWiseConvolution && kernel_w == 3 && kernel_h == 3 &&
                // computing at most 1 pixel from each side can involve padding
                max(stride_w, dilation_w) >= pad_l && max(stride_h, dilation_h) >= pad_t &&
                pad_l <= 1 && pad_t <= 1;

            if( !depthWiseConvolution && nstripes >= batchSize*2 )
            {
                stripesPerSample = nstripes/batchSize;
                stripeSize = (int)alignSize((outPlaneSize + stripesPerSample - 1)/stripesPerSample, 8);
                stripeSize = std::min(stripeSize, outPlaneSize);
            }
            else
            {
                stripesPerSample = 1;
                int samplesPerStripe = std::max((batchSize + nstripes - 1)/nstripes, 1);
                r.start *= samplesPerStripe;
                r.end *= samplesPerStripe;
                stripeSize = outPlaneSize;
            }

            const int8_t* data_inp0_ = input_->ptr<int8_t>();
            const int* ofstab = &ofstab_[0];
            const int8_t* wptr_orig_ = weights_->ptr<int8_t>();
            size_t wstep = weights_->step1();
            const int* biasptr_ = &biasvec_->at(0);
            const float* multptr_ = &multiplier->at(0);
            const int* lutptr_ = !activLUT_->empty() ? activLUT_->ptr<int>() : 0;
            int* data_out0_ = output_->ptr<int>();
            AutoBuffer<int8_t> rowbuf0_;
            int8_t* rowbuf0 = 0;
            bool use_rowbuf = !depthWiseConvolution;
            int blk_size = depthWiseConvolution ? outPlaneSize : min((int)BLK_SIZE, stripeSize);

            // im2row buffer is not used for depth-wise convolution
            if(use_rowbuf)
            {
                size_t rowbufsz = alignSize(karea*blk_size_cn, valign)*min((int)BLK_SIZE, blk_size);
                //printf("karea=%d, blk_size_cn=%d, rowbufsz=%d, stripeSize=%d\n", karea, blk_size_cn, (int)rowbufsz, stripeSize);
                rowbuf0_.allocate(rowbufsz + valign);
                rowbuf0 = alignPtr(rowbuf0_.data(), (int)(valign*sizeof(int8_t)));
                // we clear the buffer once; ultimately, it lets us to avoid
                // tail processing after running the unrolled/vectorized loop.
                // the main idea is to make sure that the tail (a.k.a. padding) of each row
                // (i.e. the elements with indices between vsz=karea*ncn and vsz_a)
                // does not contain NaNs or Infs. Because the padding in the weights
                // matrix is explicitly initialized with 0's, we handle all other
                // cases nicely, i.e. we can skip expliciting re-initialization
                // of the padding - we just retain elements from the previous iteration
                // of the loop over channels (cn0).
                memset(rowbuf0, (int8_t)inpZp, rowbufsz*sizeof(rowbuf0[0]) );
            }

            for( int stripe = r.start; stripe < r.end; stripe++ )
            {
                int subsampleIdx = stripe/stripesPerSample;
                if( subsampleIdx >= batchSize )
                    break;
                int stripeStart = (int)((stripe - subsampleIdx*stripesPerSample)*stripeSize);
                int stripeEnd = (int)std::min(stripeStart + stripeSize, outPlaneSize);
                const int8_t* data_inp0 = data_inp0_ + subsampleIdx*inpPlaneSize*inpCn;
                int* data_out0 = data_out0_ + subsampleIdx*outPlaneSize*outCn;
                int startOutCn = (subsampleIdx % ngroups)*outCn;
                const int8_t* wptr_orig = wptr_orig_ + wstep*startOutCn;
                const int* biasptr = biasptr_ + startOutCn;
                const float* multptr = multptr_ + startOutCn;

                for( int cn0 = 0; cn0 < inpCn; cn0 += blk_size_cn )
                {
                    int cn1 = std::min(cn0 + blk_size_cn, inpCn);
                    int ncn = cn1 - cn0, vsz = karea*ncn;
                    int vsz_a = (int)alignSize(vsz, valign);
                    const int8_t* wptr = wptr_orig + cn0*karea;

                    for( int ofs0 = stripeStart; ofs0 < stripeEnd; ofs0 += blk_size )
                    {
                        int ofs, ofs1 = std::min(ofs0 + blk_size, stripeEnd);
                        int bsz = ofs1 - ofs0;

                        int out_d = ofs0 / (outH * outW);
                        int out_i = (ofs0 - out_d * outH * outW) / outW;
                        int out_j = ofs0 % outW;

                        if (depthWiseConvolution)
                        {
                            CV_Assert(out_i == 0 && out_j == 0);
                            int in_d = out_d * stride_d - pad_d;
                            const int8_t* inptr_ = data_inp0 + (cn0*depth*height + in_d*height)*width;
                            int* outptr_ = data_out0 + ofs0;

                        #if CV_TRY_AVX2
                            if(useAVX2)
                                opt_AVX2::fastDepthwiseConv(wptr, kernel_h, kernel_w,
                                    stride_h, stride_w, dilation_h, dilation_w, pad_t, pad_l,
                                    biasptr, multptr, inptr_, height, width, outptr_, out_d, outH, outW, inpZp, outZp);
                            else
                        #endif
                            {
                                const int8_t w00_ = wptr[0], w01_ = wptr[1], w02_ = wptr[2],
                                             w10 = wptr[3], w11 = wptr[4], w12 = wptr[5],
                                             w20_ = wptr[6], w21_ = wptr[7], w22_ = wptr[8];
                                int outW1 = min(outW, (width - dilation_w*(kernel_w - 1) + pad_l)/stride_w);
                                int bias = biasptr[out_d], biasCopy;
                                float mult = multptr[out_d];

                                for (int out_i = 0; out_i < outH; out_i++)
                                {
                                    int in_i = out_i * stride_h - pad_t, out_j = 0;
                                    const int8_t* imgptr0 = inptr_ + in_i*width;
                                    const int8_t* imgptr1 = imgptr0 + dilation_h*width;
                                    const int8_t* imgptr2 = imgptr0 + (dilation_h*2)*width;
                                    int8_t w00 = w00_, w01 = w01_, w02 = w02_;
                                    int8_t w20 = w20_, w21 = w21_, w22 = w22_;
                                    int out, out1;
                                    // Bias has a fused offset component. bias = bias_quantized - input_zeropoint*sum_of_weights.
                                    // In some cases below, certain weights are not used for convolution or set to zero.
                                    // So we create a copy of bias at the start and remove the weight's components as necessary.
                                    biasCopy = bias;

                                    if (in_i < 0)
                                    {
                                        biasCopy += inpZp * (w00 + w01 + w02);
                                        w00 = w01 = w02 = 0;
                                        imgptr0 = imgptr1;
                                    }
                                    else if (in_i + dilation_h*(kernel_h-1) >= height)
                                    {
                                        biasCopy += inpZp * (w20 + w21 + w22);
                                        w20 = w21 = w22 = 0;
                                        imgptr2 = imgptr1;
                                    }
                                    int* outptr = outptr_ + out_i*outW;
                                    if (pad_l > 0)
                                    {
                                        out = (int)imgptr0[0]*w01 + (int)imgptr0[dilation_w]*w02 +
                                              (int)imgptr1[0]*w11 + (int)imgptr1[dilation_w]*w12 +
                                              (int)imgptr2[0]*w21 + (int)imgptr2[dilation_w]*w22 +
                                              biasCopy + inpZp*(w00 + w10 + w20);
                                        out1 = outZp + (int)std::round(out*mult);
                                        outptr[0] = std::min(std::max(out1, -128), 127);
                                        out_j = 1;
                                    }
                                #if CV_SIMD
                                    if( stride_w == 1 )
                                    {
                                        const int out_delta = 16;
                                        v_int8x16 vw00 = v_setall_s8(w00), vw01 = v_setall_s8(w01), vw02 = v_setall_s8(w02),
                                                  vw10 = v_setall_s8(w10), vw11 = v_setall_s8(w11), vw12 = v_setall_s8(w12),
                                                  vw20 = v_setall_s8(w20), vw21 = v_setall_s8(w21), vw22 = v_setall_s8(w22);
                                        v_int32x4 vout0, vout1, vout2, vout3, vbias = v_setall_s32(biasCopy), voutzp = v_setall_s32(outZp),
                                                  outmin = v_setall_s32(-128), outmax = v_setall_s32(127);
                                        v_float32x4 vmult = v_setall_f32(mult);
                                        for( ; out_j < outW1; out_j += out_delta )
                                        {
                                            if (out_j + out_delta > outW1)
                                            {
                                                if (out_j <= pad_l)
                                                    break;
                                                out_j = outW1 - out_delta;
                                            }
                                            int in_j = out_j * stride_w - pad_l;
                                            v_int8x16 v00 = v_load(imgptr0 + in_j),
                                                      v01 = v_load(imgptr0 + in_j + dilation_w),
                                                      v02 = v_load(imgptr0 + in_j + dilation_w*2),
                                                      v10 = v_load(imgptr1 + in_j),
                                                      v11 = v_load(imgptr1 + in_j + dilation_w),
                                                      v12 = v_load(imgptr1 + in_j + dilation_w*2),
                                                      v20 = v_load(imgptr2 + in_j),
                                                      v21 = v_load(imgptr2 + in_j + dilation_w),
                                                      v22 = v_load(imgptr2 + in_j + dilation_w*2);

                                            vout0 = vout1 = vout2 = vout3 = vbias;
                                            v_expand_mul_add(v00, vw00, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v01, vw01, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v02, vw02, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v10, vw10, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v11, vw11, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v12, vw12, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v20, vw20, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v21, vw21, vout0, vout1, vout2, vout3);
                                            v_expand_mul_add(v22, vw22, vout0, vout1, vout2, vout3);

                                            vout0 = voutzp + v_round(v_cvt_f32(vout0)*vmult);
                                            vout1 = voutzp + v_round(v_cvt_f32(vout1)*vmult);
                                            vout2 = voutzp + v_round(v_cvt_f32(vout2)*vmult);
                                            vout3 = voutzp + v_round(v_cvt_f32(vout3)*vmult);

                                            vout0 = v_min(v_max(vout0, outmin), outmax);
                                            vout1 = v_min(v_max(vout1, outmin), outmax);
                                            vout2 = v_min(v_max(vout2, outmin), outmax);
                                            vout3 = v_min(v_max(vout3, outmin), outmax);

                                            v_store(outptr + out_j, vout0);
                                            v_store(outptr + out_j + 4, vout1);
                                            v_store(outptr + out_j + 8, vout2);
                                            v_store(outptr + out_j + 12, vout3);
                                        }
                                    }
                                #endif
                                    for (; out_j < outW1; out_j++)
                                    {
                                        int in_j = out_j * stride_w - pad_l;
                                        out = (int)imgptr0[in_j]*w00 + (int)imgptr0[in_j + dilation_w]*w01 + (int)imgptr0[in_j + dilation_w*2]*w02 +
                                              (int)imgptr1[in_j]*w10 + (int)imgptr1[in_j + dilation_w]*w11 + (int)imgptr1[in_j + dilation_w*2]*w12 +
                                              (int)imgptr2[in_j]*w20 + (int)imgptr2[in_j + dilation_w]*w21 + (int)imgptr2[in_j + dilation_w*2]*w22 + biasCopy;
                                        out1 = outZp + (int)std::round(out*mult);
                                        outptr[out_j] = std::min(std::max(out1, -128), 127);
                                    }

                                    for (; out_j < outW; out_j++ )
                                    {
                                        int in_j0 = out_j * stride_w - pad_l, in_j1 = in_j0 + dilation_w, in_j2 = in_j0 + dilation_w*2;
                                        int s0 = 1, s1 = 1, s2 = 1;
                                        if (in_j0 >= width)
                                        {
                                            in_j0 = 0;
                                            s0 = 0;
                                            biasCopy += inpZp*(w00 + w10 + w20);
                                        }
                                        if (in_j1 >= width)
                                        {
                                            in_j1 = 0;
                                            s1 = 0;
                                            biasCopy += inpZp*(w01 + w11 + w21);
                                        }
                                        if (in_j2 >= width)
                                        {
                                            in_j2 = 0;
                                            s2 = 0;
                                            biasCopy += inpZp*(w02 + w12 + w22);
                                        }
                                        out = (int)imgptr0[in_j0]*w00*s0 + (int)imgptr0[in_j1]*w01*s1 + (int)imgptr0[in_j2]*w02*s2 +
                                              (int)imgptr1[in_j0]*w10*s0 + (int)imgptr1[in_j1]*w11*s1 + (int)imgptr1[in_j2]*w12*s2 +
                                              (int)imgptr2[in_j0]*w20*s0 + (int)imgptr2[in_j1]*w21*s1 + (int)imgptr2[in_j2]*w22*s2 + biasCopy;
                                        out1 = outZp + (int)std::round(out*mult);
                                        outptr[out_j] = std::min(std::max(out1, -128), 127);
                                    }
                                }
                            }
                            continue;
                        }
                        // do im2row for a part of input tensor
                        int8_t* rowbuf = rowbuf0;

                        if (isConv1D)
                        {
                            for( ofs = ofs0; ofs < ofs1; out_j = 0, ++out_i )
                            {
                                int delta = std::min(ofs1 - ofs, outW - out_j);
                                int out_j1 = out_j + delta;

                                int in_j = out_j * stride_w - pad_l;
                                const int8_t* imgptr = data_inp0 + cn0*width + in_j;
                                ofs += delta;

                                // do im2row for a part of input tensor
                                if( is1x1 )
                                {
                                    for( ; out_j < out_j1; out_j++, rowbuf += vsz_a, imgptr += stride_w )
                                    {
                                        for( k = 0; k < vsz; k++ )
                                            rowbuf[k] = imgptr[k*inpPlaneSize];
                                    }
                                }
                                else
                                {
                                    for( ; out_j < out_j1; out_j++, rowbuf += vsz_a, imgptr += stride_w, in_j += stride_w )
                                    {
                                        // this condition should be true for most of the tensor elements, i.e.
                                        // most of the time the kernel aperture is inside the tensor X-Y plane.
                                        if( out_j + 2 <= out_j1 && 0 <= in_j && in_j + stride_w*2 <= width - (kernel_w-1)*dilation_w )
                                        {
                                            for( k = 0; k < vsz; k++ )
                                            {
                                                int k1 = ofstab[k];
                                                int8_t v0 = imgptr[k1];
                                                int8_t v1 = imgptr[k1 + stride_w];
                                                rowbuf[k] = v0;
                                                rowbuf[k+vsz_a] = v1;
                                            }
                                            out_j++;
                                            rowbuf += vsz_a;
                                            imgptr += stride_w;
                                            in_j += stride_w;
                                        }
                                        else
                                        {
                                            int i0 = std::max(0, (-in_j + dilation_w-1)/dilation_w);
                                            int i1 = std::min(kernel_w, (width - in_j + dilation_w-1)/dilation_w);

                                            // here some non-continuous sub-row of the row will not be
                                            // filled from the tensor; we need to make sure that the uncovered
                                            // elements are explicitly set to 0's. the easiest way is to
                                            // set all the elements to 0's before the loop.
                                            memset(rowbuf, (int8_t)inpZp, vsz*sizeof(rowbuf[0]));
                                            for( k = 0; k < ncn; k++ )
                                            {
                                                for( i = i0; i < i1; i++ )
                                                {
                                                    int imgofs = k*width + i*dilation_w;
                                                    rowbuf[k*kernel_w + i] = imgptr[imgofs];
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                        else if (isConv2D)
                        {
                            if( is1x1 && stride_w == 1 && stride_h == 1 )
                            {
                                const int8_t* imgptr = data_inp0 + (cn0*height + out_i)*width + out_j;
                                for( int j = 0; j < bsz; j++, rowbuf += vsz_a )
                                {
                                    if( j + 4 <= bsz )
                                    {
                                        k = 0;
                                        for( ; k < vsz; k++ )
                                        {
                                            const int8_t* inp = imgptr + j + k*inpPlaneSize;
                                            int8_t v0 = inp[0], v1 = inp[1], v2 = inp[2], v3 = inp[3];
                                            rowbuf[k] = v0;
                                            rowbuf[k + vsz_a] = v1;
                                            rowbuf[k + vsz_a*2] = v2;
                                            rowbuf[k + vsz_a*3] = v3;
                                        }
                                        j += 3;
                                        rowbuf += vsz_a*3;
                                    }
                                    else
                                    {
                                        for( k = 0; k < vsz; k++ )
                                        {
                                            rowbuf[k] = imgptr[j + k*inpPlaneSize];
                                        }
                                    }
                                }
                            }
                            else
                            for( ofs = ofs0; ofs < ofs1; out_j = 0, ++out_i )
                            {
                                int delta = std::min(ofs1 - ofs, outW - out_j);
                                int out_j1 = out_j + delta;

                                int in_i = out_i * stride_h - pad_t;
                                int in_j = out_j * stride_w - pad_l;
                                const int8_t* imgptr = data_inp0 + (cn0*height + in_i)*width + in_j;
                                ofs += delta;

                                // do im2row for a part of input tensor
                                if( is1x1 )
                                {
                                    for( ; out_j < out_j1; out_j++, rowbuf += vsz_a, imgptr += stride_w )
                                    {
                                        for( k = 0; k < vsz; k++ )
                                            rowbuf[k] = imgptr[k*inpPlaneSize];
                                    }
                                }
                                else
                                {
                                    bool ok_i = 0 <= in_i && in_i < height - (kernel_h-1)*dilation_h;
                                    int i0 = std::max(0, (-in_i + dilation_h-1)/dilation_h);
                                    int i1 = std::min(kernel_h, (height - in_i + dilation_h-1)/dilation_h);

                                    for( ; out_j < out_j1; out_j++, rowbuf += vsz_a, imgptr += stride_w, in_j += stride_w )
                                    {
                                        // this condition should be true for most of the tensor elements, i.e.
                                        // most of the time the kernel aperture is inside the tensor X-Y plane.
                                        if( ok_i && out_j + 2 <= out_j1 && 0 <= in_j && in_j + stride_w*2 <= width - (kernel_w-1)*dilation_w )
                                        {
                                            for( k = 0; k < vsz; k++ )
                                            {
                                                int k1 = ofstab[k];
                                                int8_t v0 = imgptr[k1];
                                                int8_t v1 = imgptr[k1 + stride_w];
                                                rowbuf[k] = v0;
                                                rowbuf[k+vsz_a] = v1;
                                            }
                                            out_j++;
                                            rowbuf += vsz_a;
                                            imgptr += stride_w;
                                            in_j += stride_w;
                                        }
                                        else
                                        {
                                            int j0 = std::max(0, (-in_j + dilation_w-1)/dilation_w);
                                            int j1 = std::min(kernel_w, (width - in_j + dilation_w-1)/dilation_w);

                                            // here some non-continuous sub-row of the row will not be
                                            // filled from the tensor; we need to make sure that the uncovered
                                            // elements are explicitly set to 0's. the easiest way is to
                                            // set all the elements to 0's before the loop.
                                            memset(rowbuf, (int8_t)inpZp, vsz*sizeof(rowbuf[0]));
                                            for( k = 0; k < ncn; k++ )
                                            {
                                                for( i = i0; i < i1; i++ )
                                                {
                                                    for( j = j0; j < j1; j++ )
                                                    {
                                                        int imgofs = k*(width*height) + i*(dilation_h*width) + j*dilation_w;
                                                        rowbuf[(k*kernel_h + i)*kernel_w + j] = imgptr[imgofs];
                                                    }
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                        else
                        {
                            for( ofs = ofs0; ofs < ofs1; out_d += (out_i + 1) / outH, out_i = (out_i + 1) % outH, out_j = 0 )
                            {
                                int delta = std::min(ofs1 - ofs, outW - out_j);
                                int out_j1 = out_j + delta;

                                int in_d = out_d * stride_d - pad_d;
                                int in_i = out_i * stride_h - pad_t;
                                int in_j = out_j * stride_w - pad_l;
                                const int8_t* imgptr = data_inp0 + (cn0*depth*height + in_d*height + in_i)*width + in_j;
                                ofs += delta;

                                int d0 = std::max(0, (-in_d + dilation_d - 1) / dilation_d);
                                int d1 = std::min(kernel_d, (depth - in_d + dilation_d - 1) / dilation_d);

                                int i0 = std::max(0, (-in_i + dilation_h-1)/dilation_h);
                                int i1 = std::min(kernel_h, (height - in_i + dilation_h-1)/dilation_h);

                                for( ; out_j < out_j1; out_j++, rowbuf += vsz_a, imgptr += stride_w, in_j += stride_w )
                                {
                                    int j0 = std::max(0, (-in_j + dilation_w-1)/dilation_w);
                                    int j1 = std::min(kernel_w, (width - in_j + dilation_w-1)/dilation_w);

                                    // here some non-continuous sub-row of the row will not be
                                    // filled from the tensor; we need to make sure that the uncovered
                                    // elements are explicitly set to 0's. the easiest way is to
                                    // set all the elements to 0's before the loop.
                                    memset(rowbuf, (int8_t)inpZp, vsz*sizeof(rowbuf[0]));
                                    for( k = 0; k < ncn; k++ )
                                    {
                                        for ( d = d0; d < d1; d++)
                                        {
                                            for( i = i0; i < i1; i++ )
                                            {
                                                for( j = j0; j < j1; j++ )
                                                {
                                                    int imgofs = k*(depth*width*height) + d*dilation_d*width*height + i*(dilation_h*width) + j*dilation_w;
                                                    rowbuf[(k*kernel_d*kernel_h + d*kernel_h + i)*kernel_w + j] = imgptr[imgofs];
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                        // now compute dot product of the weights
                        // and im2row-transformed part of the tensor
                    #if CV_TRY_AVX512_SKX
                        if(useAVX512)
                            opt_AVX2::fastConv(wptr, wstep, biasptr, rowbuf0, data_out0 + ofs0,
                                          outShape, bsz, vsz, vsz_a, outZp, multptr, cn0 == 0, cn1 == inpCn);
                        else
                    #endif
                    #if CV_TRY_AVX2
                        if(useAVX2)
                            opt_AVX2::fastConv(wptr, wstep, biasptr, rowbuf0, data_out0 + ofs0,
                                          outShape, bsz, vsz, vsz_a, outZp, multptr, cn0 == 0, cn1 == inpCn);
                        else
                    #endif
                        for( int i = 0; i < outCn; i += 2 )
                        {
                            const int8_t* wptr0 = wptr + i*wstep;
                            const int8_t* wptr1 = wptr0 + wstep;
                            int* outptr0 = data_out0 + ofs0 + i*outPlaneSize;
                            int* outptr1 = outptr0 + outPlaneSize;
                            int bias0 = biasptr[i], bias1 = biasptr[i+1];
                            float mult0 = multptr[i], mult1 = multptr[i+1];

                            if( i+1 >= outCn )
                            {
                                wptr1 = wptr0;
                                outptr1 = outptr0;
                                bias1 = bias0;
                                mult1 = mult0;
                            }
                            int j = 0;
                        #if CV_SIMD128
                            v_int32x4 voutzp = v_setall_s32(outZp), outmin = v_setall_s32(-128), outmax = v_setall_s32(127);
                            v_float32x4 vmult0 = v_setall_f32(mult0), vmult1 = v_setall_f32(mult1);
                            for( ; j <= bsz - 4; j += 4 )
                            {
                                const int8_t* rptr = rowbuf0 + j*vsz_a;
                                v_int32x4 s0, s1;

                                if( cn0 == 0 )
                                {
                                    s0 = v_setall_s32(bias0);
                                    s1 = v_setall_s32(bias1);
                                }
                                else
                                {
                                    s0 = v_load(outptr0 + j);
                                    s1 = v_load(outptr1 + j);
                                }

                                v_int32x4 vs00 = v_setzero_s32(), vs01 = v_setzero_s32(),
                                          vs02 = v_setzero_s32(), vs03 = v_setzero_s32(),
                                          vs10 = v_setzero_s32(), vs11 = v_setzero_s32(),
                                          vs12 = v_setzero_s32(), vs13 = v_setzero_s32();
                                for( k = 0; k < vsz; k += 16, rptr += 16 )
                                {
                                    v_int8x16 w0 = v_load_aligned(wptr0 + k);
                                    v_int8x16 w1 = v_load_aligned(wptr1 + k);
                                    v_int8x16 r0 = v_load_aligned(rptr);
                                    v_int8x16 r1 = v_load_aligned(rptr + vsz_a);
                                    v_int8x16 r2 = v_load_aligned(rptr + vsz_a*2);
                                    v_int8x16 r3 = v_load_aligned(rptr + vsz_a*3);

                                    vs00 = v_dotprod_expand_fast(w0, r0, vs00);
                                    vs01 = v_dotprod_expand_fast(w0, r1, vs01);
                                    vs02 = v_dotprod_expand_fast(w0, r2, vs02);
                                    vs03 = v_dotprod_expand_fast(w0, r3, vs03);

                                    vs10 = v_dotprod_expand_fast(w1, r0, vs10);
                                    vs11 = v_dotprod_expand_fast(w1, r1, vs11);
                                    vs12 = v_dotprod_expand_fast(w1, r2, vs12);
                                    vs13 = v_dotprod_expand_fast(w1, r3, vs13);
                                }
                                s0 += v_int32x4(v_reduce_sum(vs00), v_reduce_sum(vs01), v_reduce_sum(vs02), v_reduce_sum(vs03));
                                s1 += v_int32x4(v_reduce_sum(vs10), v_reduce_sum(vs11), v_reduce_sum(vs12), v_reduce_sum(vs13));
                                if( cn1 == inpCn )
                                {
                                    s0 = voutzp + v_round(v_cvt_f32(s0)*vmult0);
                                    s1 = voutzp + v_round(v_cvt_f32(s1)*vmult1);

                                    s0 = v_min(v_max(s0, outmin), outmax);
                                    s1 = v_min(v_max(s1, outmin), outmax);
                                }
                                v_store(outptr0 + j, s0);
                                v_store(outptr1 + j, s1);
                            }
                        #endif
                            for( ; j < bsz; j++ )
                            {
                                const int8_t* rptr = rowbuf0 + j*vsz_a;
                                int s00, s10;

                                if( cn0 == 0 )
                                {
                                    s00 = bias0;
                                    s10 = bias1;
                                }
                                else
                                {
                                    s00 = outptr0[j];
                                    s10 = outptr1[j];
                                }

                                for( k = 0; k < vsz; k++ )
                                {
                                    int8_t r0 = rptr[k];
                                    s00 += (int)wptr0[k] * r0;
                                    s10 += (int)wptr1[k] * r0;
                                }
                                if( cn1 == inpCn )
                                {
                                    int out0 = outZp + (int)std::round(s00*mult0);
                                    int out1 = outZp + (int)std::round(s10*mult1);

                                    s00 = std::min(std::max(out0, -128), 127);
                                    s10 = std::min(std::max(out1, -128), 127);
                                }

                                outptr0[j] = s00;
                                outptr1[j] = s10;
                            }
                        }
                    }
                }
                if( activ_ )
                    activ_->forwardSlice(data_out0 + stripeStart, lutptr_,
                                         data_out0 + stripeStart, (int)(stripeEnd - stripeStart),
                                         outPlaneSize, startOutCn, startOutCn + outCn);
            }
        }
    };

    void forward(InputArrayOfArrays inputs_arr, OutputArrayOfArrays outputs_arr, OutputArrayOfArrays internals_arr) CV_OVERRIDE
    {
        CV_TRACE_FUNCTION();
        CV_TRACE_ARG_VALUE(name, "name", name.c_str());

#if CV_SSE3
        uint32_t ftzMode = _MM_GET_FLUSH_ZERO_MODE();
        uint32_t dazMode = _MM_GET_DENORMALS_ZERO_MODE();
        _MM_SET_FLUSH_ZERO_MODE(_MM_FLUSH_ZERO_ON);
        _MM_SET_DENORMALS_ZERO_MODE(_MM_DENORMALS_ZERO_ON);
#endif

        std::vector<Mat> inputs, outputs;
        inputs_arr.getMatVector(inputs);
        outputs_arr.getMatVector(outputs);

        /*if (inputs[0].dims > 3) {
            printf("conv %s: input (%d x %d x %d x %d), kernel (%d x %d), pad (%d x %d), stride (%d x %d), dilation (%d x %d)\n",
                   name.c_str(), inputs[0].size[0], inputs[0].size[1], inputs[0].size[2], inputs[0].size[3],
                   kernel.width, kernel.height, pad.width, pad.height,
                   stride.width, stride.height, dilation.width, dilation.height);
        }
        else {
            printf("conv %s: input (%d x %d x %d), kernel (%d x %d), pad (%d x %d), stride (%d x %d), dilation (%d x %d)\n",
                   name.c_str(), inputs[0].size[0], inputs[0].size[1], inputs[0].size[2],
                   kernel.width, kernel.height, pad.width, pad.height,
                   stride.width, stride.height, dilation.width, dilation.height);
        }*/

        int inpGroupCn = blobs[0].size[1];
        CV_Assert_N(inputs.size() == (size_t)1, inputs[0].size[1] % inpGroupCn == 0,
                    outputs.size() == 1, inputs[0].data != outputs[0].data);

        int ngroups = inputs[0].size[1] / inpGroupCn;
        CV_Assert(outputs[0].size[1] % ngroups == 0);

        int nstripes = std::max(getNumThreads(), 1);
        Mat outputInt32 = Mat(shape(outputs[0]), CV_32S);

        ParallelConv::run(inputs[0], outputInt32, weightsMat, outputMultiplier, biasvec, activationLUT, kernel_size, strides,
                          pads_begin, pads_end, dilations, activ.get(), ngroups, nstripes, input_zp, output_zp);

        outputInt32.convertTo(outputs[0], CV_8S);

#if CV_SSE3
        _MM_SET_FLUSH_ZERO_MODE(ftzMode);
        _MM_SET_DENORMALS_ZERO_MODE(dazMode);
#endif
    }

    virtual int64 getFLOPS(const std::vector<MatShape> &inputs,
                           const std::vector<MatShape> &outputs) const CV_OVERRIDE
    {
        CV_Assert(inputs.size() == outputs.size());

        int64 flops = 0;
        int karea = std::accumulate(kernel_size.begin(), kernel_size.end(), 1, std::multiplies<size_t>());
        for (int i = 0; i < outputs.size(); i++)
        {
            flops += total(outputs[i])*(CV_BIG_INT(2)*karea*inputs[i][1] + 1);
        }
        return flops;
    }
};

Ptr<BaseConvolutionLayer> ConvolutionLayerInt8::create(const LayerParams &params)
{
    return Ptr<BaseConvolutionLayer>(new ConvolutionLayerInt8Impl(params));
}

}
}