视觉智能平台视频人像增强的签名;这个参数在API文档中没找到，应该填什么日期的版本？

您好，视觉智能开放平台人像增强的版本号建议可以填2020-03-20尝试，根据示例代码可以看出来

// 引入依赖包
// 最低SDK版本要求：videoenhan20200320的SDK版本需大于等于2.0.14。
// 可以在此仓库地址中引用最新版本SDK：https://mvnrepository.com/artifact/com.aliyun/videoenhan20200320
// <dependency>
//       <groupId>com.aliyun</groupId>
//       <artifactId>videoenhan20200320</artifactId>
//       <version>${aliyun.videoenhan.version}</version>
// </dependency>

import com.aliyun.tea.TeaException;
import com.aliyun.tea.TeaModel;
import com.aliyun.videoenhan20200320.models.EnhancePortraitVideoResponse;

public class EnhancePortraitVideo {

    public static com.aliyun.videoenhan20200320.Client createClient(String accessKeyId, String accessKeySecret) throws Exception {
        /*
          初始化配置对象com.aliyun.teaopenapi.models.Config
          Config对象存放 AccessKeyId、AccessKeySecret、endpoint等配置
         */
         com.aliyun.teaopenapi.models.Config config = new com.aliyun.teaopenapi.models.Config()
                .setAccessKeyId(accessKeyId)
                .setAccessKeySecret(accessKeySecret);
        // 访问的域名
        config.endpoint = "videoenhan.cn-shanghai.aliyuncs.com";
        return new com.aliyun.videoenhan20200320.Client(config);
    }

    public static void main(String[] args) throws Exception {
        // 创建AccessKey ID和AccessKey Secret，请参见：https://help.aliyun.com/document_detail/175144.html
        // 如果您使用的是RAM用户的AccessKey，还需要为子账号授予权限AliyunVIAPIFullAccess，请参见：https://help.aliyun.com/document_detail/145025.html
        // 从环境变量读取配置的AccessKey ID和AccessKey Secret。运行代码示例前必须先配置环境变量。
        String accessKeyId = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_ID");
        String accessKeySecret = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_SECRET"); 
        com.aliyun.videoenhan20200320.Client client = EnhancePortraitVideo.createClient(accessKeyId, accessKeySecret);
        com.aliyun.videoenhan20200320.models.EnhancePortraitVideoRequest enhancePortraitVideoRequest = new com.aliyun.videoenhan20200320.models.EnhancePortraitVideoRequest()
                .setVideoUrl("http://viapi-test.oss-cn-shanghai.aliyuncs.com/viapi-3.0domepic/videoenhan/SuperResolveVideo/SuperResolveVideo5.mp4");
        com.aliyun.teautil.models.RuntimeOptions runtime = new com.aliyun.teautil.models.RuntimeOptions();
        try {
            // 复制代码运行请自行打印 API 的返回值
            EnhancePortraitVideoResponse response = client.enhancePortraitVideoWithOptions(enhancePortraitVideoRequest, runtime);
            System.out.println(com.aliyun.teautil.Common.toJSONString(TeaModel.buildMap(response)));
        } catch (TeaException error) {
            // 获取整体报错信息
            System.out.println(com.aliyun.teautil.Common.toJSONString(error));
            // 获取单个字段
            System.out.println(error.getCode());
        }
    }
}

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