pico full angle detection

snippets.cpp

namespace {

const int MAX_DETS = 5;
const float SCALE_FACTOR = 1.1f;
const float STRIDE_FACTOR = 0.1f;
const float QUALITY_THRESH = 10.0f;
const float ANGLE_STEP = 45.0f;

}

struct PicoObject {
    float row;
    float col;
    float size;
    float quality;
};

void PicoFaceDetector::DoDetect(const Image &img, const cv::Rect2f &roi, std::vector<Face> &faces,
                                int minSize, int maxSize)
{
    if (cascade_ == NULL) {
        return;
    }
    
    cv::Mat gray = cvext::empty(roi) ? img.gray : cvext::roi(img.gray, roi);
    if (maxSize == 0) {
        maxSize = std::min(gray.cols, gray.rows);
    }
    
    const int NUM_ANGLES = 360.0f / ANGLE_STEP;
    PicoObject rcsq[NUM_ANGLES * MAX_DETS] = {0};
    int ndets[NUM_ANGLES] = {0};
    
    cvext::parallel_for(0, NUM_ANGLES, [&](int r) {
        ndets[r] = find_objects((float *)&rcsq[r * MAX_DETS], MAX_DETS, cascade_, r * ANGLE_STEP / 360.0f,
                                gray.data, gray.rows, gray.cols, (int)gray.step[0],
                                SCALE_FACTOR, STRIDE_FACTOR, minSize, maxSize);
    });
    
    int total = ndets[0];
    int idx[NUM_ANGLES * MAX_DETS] = {0};
    for (int i = 1; i < NUM_ANGLES; i++) {
        for (int j = 0; j < ndets[i]; j++, total++) {
            rcsq[total] = rcsq[i * MAX_DETS + j];
            idx[total] = i;
        }
    }
    
    float qs[NUM_ANGLES * MAX_DETS] = {0};
    for (int i = 0; i < total; i++) {
        qs[i] = rcsq[i].quality;
    }
    
    int cc[NUM_ANGLES * MAX_DETS] = {0};
    int remain = cluster_detections((float *)rcsq, total, cc);
    
    for (int i = 0; i < remain; i++) {
        if (rcsq[i].quality < QUALITY_THRESH) {
            continue;
        }
        
        float sumqs[NUM_ANGLES] = {0};
        for (int j = 0; j < total; j++) {
            if (cc[j] == i + 1) {
                sumqs[idx[j]] += qs[j];
            }
        }
        float maxqs = 0, angle = 0;
        for (int j = 0; j < NUM_ANGLES; j++) {
            if (sumqs[j] > maxqs) {
                maxqs = sumqs[j];
                angle = j * ANGLE_STEP;
            }
        }
        
        cv::Point2f center(rcsq[i].col + roi.x, rcsq[i].row + roi.y);
        // face rect is a little too up, fix it by move center point down
        cvext::move(center, rcsq[i].size / 10, angle);
        
        cv::Rect2f rect(center.x - rcsq[i].size / 2, center.y - rcsq[i].size / 2, rcsq[i].size, rcsq[i].size);
        faces.emplace_back(img, rect);
        faces.back().pose.roll = angle;
        faces.back().score = rcsq[i].quality;
    }
}