检测多个对象

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In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

Roles required to select or create a project

• Select a project: Selecting a project doesn't require a specific IAM role—you can select any project that you've been granted a role on.
• Create a project: To create a project, you need the Project Creator role (roles/resourcemanager.projectCreator), which contains the resourcemanager.projects.create permission. Learn how to grant roles.

Go to project selector

Verify that billing is enabled for your Google Cloud project.

Enable the Vision API.

Roles required to enable APIs

To enable APIs, you need the Service Usage Admin IAM role (roles/serviceusage.serviceUsageAdmin), which contains the serviceusage.services.enable permission. Learn how to grant roles.

Enable the API

Install the Google Cloud CLI.

如果您使用的是外部身份提供方 (IdP)，则必须先使用联合身份登录 gcloud CLI。

如需初始化 gcloud CLI，请运行以下命令：

gcloud init

In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

Roles required to select or create a project

• Select a project: Selecting a project doesn't require a specific IAM role—you can select any project that you've been granted a role on.
• Create a project: To create a project, you need the Project Creator role (roles/resourcemanager.projectCreator), which contains the resourcemanager.projects.create permission. Learn how to grant roles.

Go to project selector

Verify that billing is enabled for your Google Cloud project.

Enable the Vision API.

Roles required to enable APIs

To enable APIs, you need the Service Usage Admin IAM role (roles/serviceusage.serviceUsageAdmin), which contains the serviceusage.services.enable permission. Learn how to grant roles.

Enable the API

Install the Google Cloud CLI.

如果您使用的是外部身份提供方 (IdP)，则必须先使用联合身份登录 gcloud CLI。

如需初始化 gcloud CLI，请运行以下命令：

gcloud init

检测本地图片中的对象

您可以使用 Vision API 对本地图片文件执行特征检测。

对于 REST 请求，请将图片文件的内容作为 base64 编码的字符串在请求正文中发送。

对于 gcloud 和客户端库请求，请在请求中指定本地图片的路径。

REST

在使用任何请求数据之前，请先进行以下替换：

• BASE64_ENCODED_IMAGE：二进制图片数据的 base64 表示（ASCII 字符串）。此字符串应类似于以下字符串：
  • /9j/4QAYRXhpZgAA...9tAVx/zDQDlGxn//2Q==
  如需了解详情，请参阅 base64 编码主题。
• RESULTS_INT：（可选）要返回的结果的整数值。如果您省略 "maxResults" 字段及其值，则 API 会默认返回 10 个结果。此字段不适用于以下功能类型：TEXT_DETECTION、DOCUMENT_TEXT_DETECTION 或 CROP_HINTS。
• PROJECT_ID：您的 Google Cloud 项目 ID。

HTTP 方法和网址：

POST https://vision.googleapis.com/v1/images:annotate

请求 JSON 正文：

{
  "requests": [
    {
      "image": {
        "content": "BASE64_ENCODED_IMAGE"
      },
      "features": [
        {
          "maxResults": RESULTS_INT,
          "type": "OBJECT_LOCALIZATION"
        },
      ]
    }
  ]
}

如需发送请求，请选择以下方式之一：

curl

将请求正文保存在名为 request.json 的文件中，然后执行以下命令：

curl -X POST \
     -H "Authorization: Bearer $(gcloud auth print-access-token)" \
     -H "x-goog-user-project: PROJECT_ID" \
     -H "Content-Type: application/json; charset=utf-8" \
     -d @request.json \
     "https://vision.googleapis.com/v1/images:annotate"

PowerShell

将请求正文保存在名为 request.json 的文件中，然后执行以下命令：

$cred = gcloud auth print-access-token
$headers = @{ "Authorization" = "Bearer $cred"; "x-goog-user-project" = "PROJECT_ID" }

Invoke-WebRequest `
    -Method POST `
    -Headers $headers `
    -ContentType: "application/json; charset=utf-8" `
    -InFile request.json `
    -Uri "https://vision.googleapis.com/v1/images:annotate" | Select-Object -Expand Content

如果请求成功，服务器将返回一个 200 OK HTTP 状态代码以及 JSON 格式的响应。

响应：

响应

{
  "responses": [
    {
      "localizedObjectAnnotations": [
        {
          "mid": "/m/01bqk0",
          "name": "Bicycle wheel",
          "score": 0.89648587,
          "boundingPoly": {
            "normalizedVertices": [
              {
                "x": 0.32076266,
                "y": 0.78941387
              },
              {
                "x": 0.43812272,
                "y": 0.78941387
              },
              {
                "x": 0.43812272,
                "y": 0.97331065
              },
              {
                "x": 0.32076266,
                "y": 0.97331065
              }
            ]
          }
        },
        {
          "mid": "/m/0199g",
          "name": "Bicycle",
          "score": 0.886761,
          "boundingPoly": {
            "normalizedVertices": [
              {
                "x": 0.312,
                "y": 0.6616471
              },
              {
                "x": 0.638353,
                "y": 0.6616471
              },
              {
                "x": 0.638353,
                "y": 0.9705882
              },
              {
                "x": 0.312,
                "y": 0.9705882
              }
            ]
          }
        },
        {
          "mid": "/m/01bqk0",
          "name": "Bicycle wheel",
          "score": 0.6345275,
          "boundingPoly": {
            "normalizedVertices": [
              {
                "x": 0.5125398,
                "y": 0.760708
              },
              {
                "x": 0.6256646,
                "y": 0.760708
              },
              {
                "x": 0.6256646,
                "y": 0.94601655
              },
              {
                "x": 0.5125398,
                "y": 0.94601655
              }
            ]
          }
        },
        {
          "mid": "/m/06z37_",
          "name": "Picture frame",
          "score": 0.6207608,
          "boundingPoly": {
            "normalizedVertices": [
              {
                "x": 0.79177403,
                "y": 0.16160682
              },
              {
                "x": 0.97047985,
                "y": 0.16160682
              },
              {
                "x": 0.97047985,
                "y": 0.31348917
              },
              {
                "x": 0.79177403,
                "y": 0.31348917
              }
            ]
          }
        },
        {
          "mid": "/m/0h9mv",
          "name": "Tire",
          "score": 0.55886006,
          "boundingPoly": {
            "normalizedVertices": [
              {
                "x": 0.32076266,
                "y": 0.78941387
              },
              {
                "x": 0.43812272,
                "y": 0.78941387
              },
              {
                "x": 0.43812272,
                "y": 0.97331065
              },
              {
                "x": 0.32076266,
                "y": 0.97331065
              }
            ]
          }
        },
        {
          "mid": "/m/02dgv",
          "name": "Door",
          "score": 0.5160098,
          "boundingPoly": {
            "normalizedVertices": [
              {
                "x": 0.77569866,
                "y": 0.37104446
              },
              {
                "x": 0.9412425,
                "y": 0.37104446
              },
              {
                "x": 0.9412425,
                "y": 0.81507325
              },
              {
                "x": 0.77569866,
                "y": 0.81507325
              }
            ]
          }
        }
      ]
    }
  ]
}

Go

试用此示例之前，请按照《Vision 快速入门：使用客户端库》中的 Go 设置说明进行操作。 如需了解详情，请参阅 Vision Go API 参考文档。

如需向 Vision 进行身份验证，请设置应用默认凭证。如需了解详情，请参阅为本地开发环境设置身份验证。

// localizeObjects gets objects and bounding boxes from the Vision API for an image at the given file path.
func localizeObjects(w io.Writer, file string) error {
	ctx := context.Background()

	client, err := vision.NewImageAnnotatorClient(ctx)
	if err != nil {
		return err
	}

	f, err := os.Open(file)
	if err != nil {
		return err
	}
	defer f.Close()

	image, err := vision.NewImageFromReader(f)
	if err != nil {
		return err
	}
	annotations, err := client.LocalizeObjects(ctx, image, nil)
	if err != nil {
		return err
	}