cascadeClassifier.php

<?php
use CV\Mat;
use CV\CascadeClassifier;
use CV\Size;
use CV\Point;
use CV\Scalar;
use CV\VideoCapture;
use const CV\{
    COLOR_BGR2GRAY, CASCADE_SCALE_IMAGE
};
use function CV\{
    cvtColor, equalizeHist, ellipse, circle, imshow, waitKey
};

$face_cascade_name = "haarcascade_frontalface_alt.xml";
$eyes_cascade_name = "haarcascade_eye_tree_eyeglasses.xml";
$face_cascade = new CascadeClassifier();
$eyes_cascade = new CascadeClassifier();
$window_name = "Capture - Face detection";

function detectAndDisplay(Mat $frame)
{
    global $face_cascade;
    global $eyes_cascade;
    global $window_name;
    $faces = [];
    $frame_gray = null;
    $frame_gray = cvtColor($frame, COLOR_BGR2GRAY);
    equalizeHist($frame_gray, $frame_gray);
    //-- Detect faces
    $face_cascade->detectMultiScale($frame_gray, $faces, 1.1, 2, 0 | CASCADE_SCALE_IMAGE, new Size(30, 30));
    for ($i = 0; $i < count($faces); $i++) {
        $center = new Point($faces[$i]->x + $faces[$i]->width / 2, $faces[$i]->y + $faces[$i]->height / 2);
        ellipse($frame, $center, new Size($faces[$i]->width / 2, $faces[$i]->height / 2), 0, 0, 360, new Scalar(255, 0, 255), 4, 8, 0);
        $faceROI = $frame_gray->getImageROI($faces[$i]);
        $eyes = [];
        //-- In each face, detect eyes
        $eyes_cascade->detectMultiScale($faceROI, $eyes, 1.1, 2, 0 | CASCADE_SCALE_IMAGE, new Size(30, 30));
        for ($j = 0; $j < count($eyes); $j++) {
            $eye_center = new Point ($faces[$i]->x + $eyes[$j]->x + $eyes[$j]->width / 2, $faces[$i]->y + $eyes[$j]->y + $eyes[$j]->height / 2);
            $radius = round(($eyes[$j]->width + $eyes[$j]->height) * 0.25);
            circle($frame, $eye_center, $radius, new Scalar(255, 0, 0), 4, 8, 0);
        }
    }
    //-- Show what you got
    imshow($window_name, $frame);
}

function run()
{
    global $face_cascade;
    global $face_cascade_name;
    global $eyes_cascade;
    global $eyes_cascade_name;
    $capture = new VideoCapture();
    $frame = null;
    //-- 1. Load the cascades
    if (!$face_cascade->load($face_cascade_name)) {
        printf("--(!)Error loading face cascade\n");
        return -1;
    };
    if (!$eyes_cascade->load($eyes_cascade_name)) {
        printf("--(!)Error loading eyes cascade\n");
        return -1;
    };
    //-- 2. Read the video stream
    $capture->open(-1);
    if (!$capture->isOpened()) {
        printf("--(!)Error opening video capture\n");
        return -1;
    }
    while ($capture->read($frame)) {
        if ($frame->empty()) {
            printf(" --(!) No captured frame -- Break!");
            break;
        }
        //-- 3. Apply the classifier to the frame
        detectAndDisplay($frame);
        $key = waitKey(10);
        if ($key == 27) {
            break;
        } // escape
    }
    return 0;
}

run();