opencv/modules/dnn/src/nms.cpp

// 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.
//
// Copyright (C) 2017, Intel Corporation, all rights reserved.
// Third party copyrights are property of their respective owners.

#include "precomp.hpp"
#include "nms.inl.hpp"

#include <opencv2/imgproc.hpp>

namespace cv
{
namespace dnn
{
CV__DNN_EXPERIMENTAL_NS_BEGIN

static inline float rectOverlap(const Rect& a, const Rect& b)
{
    return 1.f - static_cast<float>(jaccardDistance(a, b));
}

void NMSBoxes(const std::vector<Rect>& bboxes, const std::vector<float>& scores,
                          const float score_threshold, const float nms_threshold,
                          std::vector<int>& indices, const float eta, const int top_k)
{
    CV_Assert(bboxes.size() == scores.size(), score_threshold >= 0,
        nms_threshold >= 0, eta > 0);
    NMSFast_(bboxes, scores, score_threshold, nms_threshold, eta, top_k, indices, rectOverlap);
}

static inline float rotatedRectIOU(const RotatedRect& a, const RotatedRect& b)
{
    std::vector<Point2f> inter, hull;
    int res = rotatedRectangleIntersection(a, b, inter);
    if (inter.empty() || res == INTERSECT_NONE)
        return 0.0f;
    if (res == INTERSECT_FULL)
        return 1.0f;
    convexHull(inter, hull);
    float interArea = contourArea(hull);
    return interArea / (a.size.area() + b.size.area() - interArea);
}

void NMSBoxes(const std::vector<RotatedRect>& bboxes, const std::vector<float>& scores,
              const float score_threshold, const float nms_threshold,
              std::vector<int>& indices, const float eta, const int top_k)
{
    CV_Assert(bboxes.size() == scores.size(), score_threshold >= 0,
        nms_threshold >= 0, eta > 0);
    NMSFast_(bboxes, scores, score_threshold, nms_threshold, eta, top_k, indices, rotatedRectIOU);
}

CV__DNN_EXPERIMENTAL_NS_END
}// dnn
}// cv