- (BOOL)checkImageHasFace        {            BOOL hasFace = NO;            CIImage *begingImage = [[CIImage alloc] initWithImage:_postImage];            //创建CIDetector对象，options使用NSDictionary设置采用高品质还是低品质，这里使用低品质。            CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeFace context:nil options:[NSDictionary dictionaryWithObject:CIDetectorAccuracyLow forKey:CIDetectorAccuracy]];            //返回数组中包含图片脸部特征信息            NSArray *faceFeatures = [detector featuresInImage:begingImage];            for (CIFaceFeature *faceFeature in faceFeatures) {                //左眼位置、右眼位置和嘴的位置                if (faceFeature.hasLeftEyePosition&&faceFeature.hasRightEyePosition&&faceFeature.hasMouthPosition) {                    hasFace = YES;                }            }            return hasFace;        }