Question

我正在构建一个Npm包（Facematch），利用OpenCV查找两个图像之间的差异。

我写的代码似乎有用，但结果似乎经常非常错误，如果我输出检测到的面部，它并不总是在图像的同一区域中找到。即使我比较两个相同的蒙娜丽莎图像，我也很少得到0的absDiff。

var cv = require('opencv');
var async = require('async');

function Facematch () {

  this._detectObjects = function (im, callback) {
    var object, img;
    var options = {
      scale: 2
    };
    im.detectObject(cv.FACE_CASCADE, options, function (err, objects) {
      if (err) return callback(err);
      // console.log(objects);
      if (objects.length === 0) return callback('No objects found');
      for (var i in objects) {
        object = objects[i];
        img = im.roi(object.x, object.y, object.width, object.height);
        self.faces.push(img);
      }
      callback();
    });
  };

  this._calcDiff = function (callback) {
    var im1 = self.faces[0];
    var im2 = self.faces[1];
    // im1.save('im1.jpg');
    // im2.save('im2.jpg');
    var diff = new cv.Matrix(im1.width(), im1.height());
    diff.absDiff(im1, im2);
    diff.convertGrayscale();
    callback(null, diff.countNonZero());
  };

  var self = this;
  this.ims = [];
  this.faces = [];

}

Facematch.prototype.compare = function (img1, img2, callback) {

  var self = this;
  var images = [img1, img2];
  var diff;

  async.series([
    function (callback) {
      async.map(images, cv.readImage, function (err, results) {
        if (err) return callback(err);
        self.ims = results;
        callback();
      });
    },
    function (callback) {
      async.each(self.ims, self._detectObjects, callback);
    },
    function (callback) {
      if (self.faces.length < 2) return callback('Not enough faces');
      self._calcDiff(function (err, result) {
        if (err) return callback(err);
        diff = result;
        callback();
      });
    }
  ], function (err) {
    callback(err, diff);
  });

};


var imgFiles = ['Mona.jpg', 'Mona.jpg'];
var imgs = imgFiles.map(function (img) {
  return __dirname + '/images/' + img;
});

var fm = new Facematch();
fm.compare(imgs[0], imgs[1], function (err, diff) {
  if (err) throw err;
  console.log('Images absDiff is %d', diff);
});

更新

如果我将{ scale: 2 }作为选项传递给detectObject蒙娜丽莎的比赛，但是对于其他图像，它无法找到一张脸。我想这意味着图像应该在比较之前缩放到相同尺寸？

对于相同的图像，OpenCV检测到的面部不在同一位置

0 个答案: