Vision client libraries

This page shows how to get started with the Cloud Client Libraries for the Vision API. Client libraries make it easier to access Google Cloud APIs from a supported language. Although you can use Google Cloud APIs directly by making raw requests to the server, client libraries provide simplifications that significantly reduce the amount of code you need to write.

Read more about the Cloud Client Libraries and the older Google API Client Libraries in Client libraries explained .

Install the client library

C++

See Setting up a C++ development environment for details about this client library's requirements and install dependencies.

C#

If you are using Visual Studio 2017 or higher, open nuget package manager window and type the following:

Install-Package Google.Apis

If you are using .NET Core command-line interface tools to install your dependencies, run the following command:

dotnet add package Google.Apis

For more information, see Setting Up a C# Development Environment .

Go

go get cloud.google.com/go/vision/apiv1

For more information, see Setting Up a Go Development Environment .

Java

If you are using Maven , add the following to your pom.xml file. For more information about BOMs, see The Google Cloud Platform Libraries BOM .

 < dependencyManagement 
>
  < dependencies 
>
    < dependency 
>
      < groupId>com 
 . 
 google 
 . 
 cloud 
< / 
 groupId 
>
      < artifactId>libraries 
 - 
 bom 
< / 
 artifactId 
>
      < version>26 
 .66.0 
< / 
 version 
>
      < type>pom 
< / 
 type 
>
      < scope>import 
< / 
 scope 
>
    < / 
 dependency 
>
  < / 
 dependencies 
>
< / 
 dependencyManagement 
>

< dependencies 
>
  < dependency 
>
    < groupId>com 
 . 
 google 
 . 
 cloud 
< / 
 groupId 
>
    < artifactId>google 
 - 
 cloud 
 - 
 vision 
< / 
 artifactId 
>
  < / 
 dependency 
>
< / 
 dependencies 
>

If you are using Gradle , add the following to your dependencies:

  implementation 
 'com.google.cloud:google-cloud-vision:3.70.0'

If you are using sbt , add the following to your dependencies:

  libraryDependencies 
 += 
 "com.google.cloud" 
 % 
 "google-cloud-vision" 
 % 
 "3.70.0"

If you're using Visual Studio Code, IntelliJ, or Eclipse, you can add client libraries to your project using the following IDE plugins:

The plugins provide additional functionality, such as key management for service accounts. Refer to each plugin's documentation for details.

For more information, see Setting Up a Java Development Environment .

Node.js

npm install @google-cloud/vision

For more information, see Setting Up a Node.js Development Environment .

PHP

composer require google/apiclient

For more information, see Using PHP on Google Cloud .

Python

pip install --upgrade google-cloud-vision

For more information, see Setting Up a Python Development Environment .

Ruby

gem install google-api-client

For more information, see Setting Up a Ruby Development Environment .

Set up authentication

To authenticate calls to Google Cloud APIs, client libraries support Application Default Credentials (ADC) ; the libraries look for credentials in a set of defined locations and use those credentials to authenticate requests to the API. With ADC, you can make credentials available to your application in a variety of environments, such as local development or production, without needing to modify your application code.

For production environments, the way you set up ADC depends on the service and context. For more information, see Set up Application Default Credentials .

For a local development environment, you can set up ADC with the credentials that are associated with your Google Account:

Install the Google Cloud CLI. After installation, initialize the Google Cloud CLI by running the following command:
```
gcloud  
init
```
If you're using an external identity provider (IdP), you must first sign in to the gcloud CLI with your federated identity .
If you're using a local shell, then create local authentication credentials for your user account:
```
gcloud  
auth  
application-default  
login
```
You don't need to do this if you're using Cloud Shell.

If an authentication error is returned, and you are using an external identity provider (IdP), confirm that you have signed in to the gcloud CLI with your federated identity .

A sign-in screen appears. After you sign in, your credentials are stored in the local credential file used by ADC .

Use the client library

The following example shows how to use the client library.

C++

  #include 
  
 "google/cloud/vision/v1/image_annotator_client.h" 
 #include <iostream> 
 int 
  
 main 
 ( 
 int 
  
 argc 
 , 
  
 char 
 * 
  
 argv 
 []) 
  
 try 
  
 { 
  
 auto 
  
 constexpr 
  
 kDefaultUri 
  
 = 
  
 "gs://cloud-samples-data/vision/label/wakeupcat.jpg" 
 ; 
  
 if 
  
 ( 
 argc 
 > 
 2 
 ) 
  
 { 
  
 std 
 :: 
 cerr 
 << 
 "Usage: " 
 << 
 argv 
 [ 
 0 
 ] 
 << 
 " [gcs-uri] 
 \n 
 " 
 << 
 "  The gcs-uri must be in gs://... format. It defaults to " 
 << 
 kDefaultUri 
 << 
 " 
 \n 
 " 
 ; 
  
 return 
  
 1 
 ; 
  
 } 
  
 auto 
  
 uri 
  
 = 
  
 std 
 :: 
 string 
 { 
 argc 
  
 == 
  
 2 
  
 ? 
  
 argv 
 [ 
 1 
 ] 
  
 : 
  
 kDefaultUri 
 }; 
  
 namespace 
  
 vision 
  
 = 
  
 :: 
 google 
 :: 
 cloud 
 :: 
 vision_v1 
 ; 
  
 auto 
  
 client 
  
 = 
  
 vision 
 :: 
 ImageAnnotatorClient 
 ( 
 vision 
 :: 
 MakeImageAnnotatorConnection 
 ()); 
  
 // Define the image we want to annotate 
  
 google 
 :: 
 cloud 
 :: 
 vision 
 :: 
 v1 
 :: 
 Image 
  
 image 
 ; 
  
 image 
 . 
 mutable_source 
 () 
 - 
> set_image_uri 
 ( 
 uri 
 ); 
  
 // Create a request to annotate this image with Request text annotations for a 
  
 // file stored in GCS. 
  
 google 
 :: 
 cloud 
 :: 
 vision 
 :: 
 v1 
 :: 
 AnnotateImageRequest 
  
 request 
 ; 
  
 * 
 request 
 . 
 mutable_image 
 () 
  
 = 
  
 std 
 :: 
 move 
 ( 
 image 
 ); 
  
 request 
 . 
 add_features 
 () 
 - 
> set_type 
 ( 
  
 google 
 :: 
 cloud 
 :: 
 vision 
 :: 
 v1 
 :: 
 Feature 
 :: 
 TEXT_DETECTION 
 ); 
  
 google 
 :: 
 cloud 
 :: 
 vision 
 :: 
 v1 
 :: 
 BatchAnnotateImagesRequest 
  
 batch_request 
 ; 
  
 * 
 batch_request 
 . 
 add_requests 
 () 
  
 = 
  
 std 
 :: 
 move 
 ( 
 request 
 ); 
  
 auto 
  
 batch 
  
 = 
  
 client 
 . 
 BatchAnnotateImages 
 ( 
 batch_request 
 ); 
  
 if 
  
 ( 
 ! 
 batch 
 ) 
  
 throw 
  
 std 
 :: 
 move 
 ( 
 batch 
 ). 
 status 
 (); 
  
 // Find the longest annotation and print it 
  
 auto 
  
 result 
  
 = 
  
 std 
 :: 
 string 
 {}; 
  
 for 
  
 ( 
 auto 
  
 const 
&  
 response 
  
 : 
  
 batch 
 - 
> responses 
 ()) 
  
 { 
  
 for 
  
 ( 
 auto 
  
 const 
&  
 annotation 
  
 : 
  
 response 
 . 
 text_annotations 
 ()) 
  
 { 
  
 if 
  
 ( 
 result 
 . 
 size 
 () 
 < 
 annotation 
 . 
 description 
 (). 
 size 
 ()) 
  
 { 
  
 result 
  
 = 
  
 annotation 
 . 
 description 
 (); 
  
 } 
  
 } 
  
 } 
  
 std 
 :: 
 cout 
 << 
 "The image contains this text: " 
 << 
 result 
 << 
 " 
 \n 
 " 
 ; 
  
 return 
  
 0 
 ; 
 } 
  
 catch 
  
 ( 
 google 
 :: 
 cloud 
 :: 
 Status 
  
 const 
&  
 status 
 ) 
  
 { 
  
 std 
 :: 
 cerr 
 << 
 "google::cloud::Status thrown: " 
 << 
 status 
 << 
 " 
 \n 
 " 
 ; 
  
 return 
  
 1 
 ; 
 }

Go

  // Sample vision-quickstart uses the Google Cloud Vision API to label an image. 
 package 
  
 main 
 import 
  
 ( 
  
 "context" 
  
 "fmt" 
  
 "log" 
  
 "os" 
  
 vision 
  
 "cloud.google.com/go/vision/apiv1" 
 ) 
 func 
  
 main 
 () 
  
 { 
  
 ctx 
  
 := 
  
 context 
 . 
 Background 
 () 
  
 // Creates a client. 
  
 client 
 , 
  
 err 
  
 := 
  
 vision 
 . 
  NewImageAnnotatorClient 
 
 ( 
 ctx 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 log 
 . 
 Fatalf 
 ( 
 "Failed to create client: %v" 
 , 
  
 err 
 ) 
  
 } 
  
 defer 
  
 client 
 . 
 Close 
 () 
  
 // Sets the name of the image file to annotate. 
  
 filename 
  
 := 
  
 "../testdata/cat.jpg" 
  
 file 
 , 
  
 err 
  
 := 
  
 os 
 . 
 Open 
 ( 
 filename 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 log 
 . 
 Fatalf 
 ( 
 "Failed to read file: %v" 
 , 
  
 err 
 ) 
  
 } 
  
 defer 
  
 file 
 . 
 Close 
 () 
  
 image 
 , 
  
 err 
  
 := 
  
 vision 
 . 
  NewImageFromReader 
 
 ( 
 file 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 log 
 . 
 Fatalf 
 ( 
 "Failed to create image: %v" 
 , 
  
 err 
 ) 
  
 } 
  
 labels 
 , 
  
 err 
  
 := 
  
 client 
 . 
  DetectLabels 
 
 ( 
 ctx 
 , 
  
 image 
 , 
  
 nil 
 , 
  
 10 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 log 
 . 
 Fatalf 
 ( 
 "Failed to detect labels: %v" 
 , 
  
 err 
 ) 
  
 } 
  
 fmt 
 . 
 Println 
 ( 
 "Labels:" 
 ) 
  
 for 
  
 _ 
 , 
  
 label 
  
 := 
  
 range 
  
 labels 
  
 { 
  
 fmt 
 . 
 Println 
 ( 
 label 
 . 
 Description 
 ) 
  
 } 
 }

Java

  // Imports the Google Cloud client library 
 import 
  
 com.google.cloud.vision.v1. AnnotateImageRequest 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. AnnotateImageResponse 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. BatchAnnotateImagesResponse 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. EntityAnnotation 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. Feature 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. Feature 
. Type 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. Image 
 
 ; 
 import 
  
 com.google.cloud.vision.v1. ImageAnnotatorClient 
 
 ; 
 import 
  
 com.google.protobuf. ByteString 
 
 ; 
 import 
  
 java.nio.file.Files 
 ; 
 import 
  
 java.nio.file.Path 
 ; 
 import 
  
 java.nio.file.Paths 
 ; 
 import 
  
 java.util.ArrayList 
 ; 
 import 
  
 java.util.List 
 ; 
 public 
  
 class 
 QuickstartSample 
  
 { 
  
 public 
  
 static 
  
 void 
  
 main 
 ( 
 String 
 ... 
  
 args 
 ) 
  
 throws 
  
 Exception 
  
 { 
  
 // Initialize client that will be used to send requests. This client only needs to be created 
  
 // once, and can be reused for multiple requests. After completing all of your requests, call 
  
 // the "close" method on the client to safely clean up any remaining background resources. 
  
 try 
  
 ( 
  ImageAnnotatorClient 
 
  
 vision 
  
 = 
  
  ImageAnnotatorClient 
 
 . 
 create 
 ()) 
  
 { 
  
 // The path to the image file to annotate 
  
 String 
  
 fileName 
  
 = 
  
 "./resources/wakeupcat.jpg" 
 ; 
  
 // Reads the image file into memory 
  
 Path 
  
 path 
  
 = 
  
 Paths 
 . 
 get 
 ( 
 fileName 
 ); 
  
 byte 
 [] 
  
 data 
  
 = 
  
 Files 
 . 
 readAllBytes 
 ( 
 path 
 ); 
  
  ByteString 
 
  
 imgBytes 
  
 = 
  
  ByteString 
 
 . 
  copyFrom 
 
 ( 
 data 
 ); 
  
 // Builds the image annotation request 
  
 List<AnnotateImageRequest> 
  
 requests 
  
 = 
  
 new 
  
 ArrayList 
<> (); 
  
  Image 
 
  
 img 
  
 = 
  
  Image 
 
 . 
 newBuilder 
 (). 
 setContent 
 ( 
 imgBytes 
 ). 
 build 
 (); 
  
  Feature 
 
  
 feat 
  
 = 
  
  Feature 
 
 . 
 newBuilder 
 (). 
 setType 
 ( 
  Type 
 
 . 
 LABEL_DETECTION 
 ). 
 build 
 (); 
  
  AnnotateImageRequest 
 
  
 request 
  
 = 
  
  AnnotateImageRequest 
 
 . 
 newBuilder 
 (). 
 addFeatures 
 ( 
 feat 
 ). 
 setImage 
 ( 
 img 
 ). 
 build 
 (); 
  
 requests 
 . 
 add 
 ( 
 request 
 ); 
  
 // Performs label detection on the image file 
  
  BatchAnnotateImagesResponse 
 
  
 response 
  
 = 
  
 vision 
 . 
 batchAnnotateImages 
 ( 
 requests 
 ); 
  
 List<AnnotateImageResponse> 
  
 responses 
  
 = 
  
 response 
 . 
  getResponsesList 
 
 (); 
  
 for 
  
 ( 
  AnnotateImageResponse 
 
  
 res 
  
 : 
  
 responses 
 ) 
  
 { 
  
 if 
  
 ( 
 res 
 . 
 hasError 
 ()) 
  
 { 
  
 System 
 . 
 out 
 . 
 format 
 ( 
 "Error: %s%n" 
 , 
  
 res 
 . 
 getError 
 (). 
 getMessage 
 ()); 
  
 return 
 ; 
  
 } 
  
 for 
  
 ( 
  EntityAnnotation 
 
  
 annotation 
  
 : 
  
 res 
 . 
 getLabelAnnotationsList 
 ()) 
  
 { 
  
 annotation 
  
 . 
 getAllFields 
 () 
  
 . 
 forEach 
 (( 
 k 
 , 
  
 v 
 ) 
  
 - 
>  
 System 
 . 
 out 
 . 
 format 
 ( 
 "%s : %s%n" 
 , 
  
 k 
 , 
  
 v 
 . 
 toString 
 ())); 
  
 } 
  
 } 
  
 } 
  
 } 
 }

Node.js

  async 
  
 function 
  
 quickstart 
 () 
  
 { 
  
 // Imports the Google Cloud client library 
  
 const 
  
 vision 
  
 = 
  
 require 
 ( 
 ' @google-cloud/vision 
' 
 ); 
  
 // Creates a client 
  
 const 
  
 client 
  
 = 
  
 new 
  
 vision 
 . 
  ImageAnnotatorClient 
 
 (); 
  
 // Performs label detection on the image file 
  
 const 
  
 [ 
 result 
 ] 
  
 = 
  
 await 
  
 client 
 . 
 labelDetection 
 ( 
 './resources/wakeupcat.jpg' 
 ); 
  
 const 
  
 labels 
  
 = 
  
  result 
 
 . 
 labelAnnotations 
 ; 
  
 console 
 . 
 log 
 ( 
 'Labels:' 
 ); 
  
 labels 
 . 
 forEach 
 ( 
 label 
  
 = 
>  
 console 
 . 
 log 
 ( 
 label 
 . 
 description 
 )); 
 } 
 quickstart 
 ();

Python

  # Imports the Google Cloud client library 
 from 
  
 google.cloud 
  
 import 
 vision 
 def 
  
 run_quickstart 
 () 
 - 
> vision 
 . 
 EntityAnnotation 
 : 
  
 """Provides a quick start example for Cloud Vision.""" 
 # Instantiates a client 
 client 
 = 
 vision 
 . 
 ImageAnnotatorClient 
 () 
 # The URI of the image file to annotate 
 file_uri 
 = 
 "gs://cloud-samples-data/vision/label/wakeupcat.jpg" 
 image 
 = 
 vision 
 . 
 Image 
 () 
 image 
 . 
 source 
 . 
 image_uri 
 = 
 file_uri 
 # Performs label detection on the image file 
 response 
 = 
 client 
 . 
 label_detection 
 ( 
 image 
 = 
 image 
 ) 
 labels 
 = 
 response 
 . 
 label_annotations 
 print 
 ( 
 "Labels:" 
 ) 
 for 
 label 
 in 
 labels 
 : 
 print 
 ( 
 label 
 . 
 description 
 ) 
 return 
 labels

Additional resources

C++

The following list contains links to more resources related to the client library for C++:

C#

The following list contains links to more resources related to the client library for C#:

Go

The following list contains links to more resources related to the client library for Go:

Java

The following list contains links to more resources related to the client library for Java:

Node.js

The following list contains links to more resources related to the client library for Node.js:

PHP

The following list contains links to more resources related to the client library for PHP:

Python

The following list contains links to more resources related to the client library for Python:

Ruby

The following list contains links to more resources related to the client library for Ruby:

Additional client libraries

In addition to the libraries shown above, Spring Cloud Google Cloud is available for Java applications. Spring Vision API helps you use Cloud Vision in any application that's built with the Spring Framework .

To get started, learn how to add Spring Cloud Vision to your application .

Try it for yourself

If you're new to Google Cloud, create an account to evaluate how Cloud Vision API performs in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.

Try Cloud Vision API free

Vision client libraries Stay organized with collections Save and categorize content based on your preferences.

Install the client library

C++

C#

Go

Java

Node.js

PHP

Python

Ruby

Set up authentication

Use the client library

C++

Go

Java

Node.js

Python

Additional resources

C++

C#

Go

Java

Node.js

PHP

Python

Ruby

Additional client libraries

Try it for yourself

Vision client libraries