很多人问过小编，什么样的美颜sdk才算好？对于这个问题，小编认为至少要符合以下几个特点。
1、稳定性强；2、识别精准；3、功能多样；4、集成容易；5、离线使用；6、支持多端；7、技术成熟。
当然，目前美颜sdk中最核心的算法还是以“人脸识别”为主，毕竟是“根基”一般的存在，因此一款美颜sdk的好坏，人脸识别起了很大的影响。下文小编将为大家剖析一下人脸识别技术的核心和代码。

一、人脸识别技术核心
1、人脸检测
2、人脸配准
3、人脸属性识别
4、人脸提特征
5、人脸比对
6、人脸验证
7、人脸检索
8、人脸聚类

二、代码分析
//
// MHOpenDemoUITests.m
// MHOpenDemoUITests
//
// Created by Apple on 2021/5/31.
//
//
//
//
//

#import <XCTest/XCTest.h>

@interface MHOpenDemoUITests : XCTestCase

@end

@implementation MHOpenDemoUITests

• (void)setUp {
  // Put setup code here. This method is called before the invocation of each test method in the class.

  // In UI tests it is usually best to stop immediately when a failure occurs.
  self.continueAfterFailure = NO;

  // In UI tests it’s important to set the initial state - such as interface orientation - required for your tests before they run. The setUp method is a good place to do this.
  }

• (void)tearDown {
  // Put teardown code here. This method is called after the invocation of each test method in the class.
  }

• (void)testExample {
  // UI tests must launch the application that they test.
  XCUIApplication *app = [[XCUIApplication alloc] init];
  [app launch];

  // Use recording to get started writing UI tests.
  // Use XCTAssert and related functions to verify your tests produce the correct results.
  }

• (void)testLaunchPerformance {
  if (@available(macOS 10.15, iOS 13.0, tvOS 13.0, *)) {
  // This measures how long it takes to launch your application.
  [self measureWithMetrics:@[[[XCTApplicationLaunchMetric alloc] init]] block:^{
  [[[XCUIApplication alloc] init] launch];
  }];
  }
  }

@end