如何在 iOS 中使用核心图像准确检测图像中的人脸？

Question

在我的应用程序中，我需要准确检测图像的面部，但我没有得到准确的输出。我使用了coreimage框架。我没有在其他地方得到右眼位置、左眼位置和嘴巴位置，甚至没有检测到微笑。

这是我的示例代码。

- (void)drawRect
{
CIDetector* detector = [CIDetector detectorOfType:CIDetectorTypeFace context:nil options:[NSDictionary dictionaryWithObject:CIDetectorAccuracyHigh forKey:CIDetectorAccuracy]];

    CIImage *img=[CIImage imageWithCGImage:imageView.image.CGImage];
    NSArray* features = [detector featuresInImage:img];

    for (CIFaceFeature *feature in features)
    {
       CGRect faceRect = feature.bounds;

UIView* face = [[UIView alloc] initWithFrame:faceRect];

        [face setBackgroundColor:[[UIColor yellowColor] colorWithAlphaComponent:0.4]];
        [imageView addSubview:face];

        if(feature.hasLeftEyePosition)
        {
            UIView* eye = [[UIView alloc] initWithFrame:CGRectMake(feature.leftEyePosition.x,feature.leftEyePosition.y, 20, 20)];
            [eye setBackgroundColor:[[UIColor blueColor] colorWithAlphaComponent:0.2]];
            [eye setCenter:feature.leftEyePosition];
            [mainView addSubview:eye];

        }

        if(feature.hasRightEyePosition)
        {
            UIView* eye = [[UIView alloc] initWithFrame:CGRectMake(feature.rightEyePosition.x, feature.rightEyePosition.y, 20, 20)];
            [eye setBackgroundColor:[[UIColor redColor] colorWithAlphaComponent:0.2]];
            [eye setCenter:feature.rightEyePosition];
            [mainView addSubview:eye];

        }

        if(feature.hasMouthPosition)
        {
            UIView* mouth = [[UIView alloc] initWithFrame:CGRectMake(feature.mouthPosition.x, feature.mouthPosition.y, 20, 20)];
            [mouth setBackgroundColor:[[UIColor greenColor] colorWithAlphaComponent:0.2]];
            [mouth setCenter:feature.mouthPosition];
            [mainView addSubview:mouth];

        }
        if(feature.hasSmile)
        {
            NSLog(@"you are smiling");
        }

    }

}

Answer 1

在y轴上翻转图像以匹配核心图像使用的坐标系，从而获得准确的位置