Generate text from an image with safety settings

This sample demonstrates how to use the Gemini model with safety settings to generate text from an image.

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For detailed documentation that includes this code sample, see the following:

Code sample

C#

Before trying this sample, follow the C# setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI C# API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.


using Google.Api.Gax.Grpc;
using Google.Cloud.AIPlatform.V1;
using System.Text;
using System.Threading.Tasks;
using static Google.Cloud.AIPlatform.V1.SafetySetting.Types;

public class WithSafetySettings
{
    public async Task<string> GenerateContent(
        string projectId = "your-project-id",
        string location = "us-central1",
        string publisher = "google",
        string model = "gemini-1.5-flash-001"
    )
    {
        var predictionServiceClient = new PredictionServiceClientBuilder
        {
            Endpoint = $"{location}-aiplatform.googleapis.com"
        }.Build();


        var generateContentRequest = new GenerateContentRequest
        {
            Model = $"projects/{projectId}/locations/{location}/publishers/{publisher}/models/{model}",
            Contents =
            {
                new Content
                {
                    Role = "USER",
                    Parts =
                    {
                        new Part { Text = "Hello!" }
                    }
                }
            },
            SafetySettings =
            {
                new SafetySetting
                {
                    Category = HarmCategory.HateSpeech,
                    Threshold = HarmBlockThreshold.BlockLowAndAbove
                },
                new SafetySetting
                {
                    Category = HarmCategory.DangerousContent,
                    Threshold = HarmBlockThreshold.BlockMediumAndAbove
                }
            }
        };

        using PredictionServiceClient.StreamGenerateContentStream response = predictionServiceClient.StreamGenerateContent(generateContentRequest);

        StringBuilder fullText = new();

        AsyncResponseStream<GenerateContentResponse> responseStream = response.GetResponseStream();
        await foreach (GenerateContentResponse responseItem in responseStream)
        {
            // Check if the content has been blocked for safety reasons.
            bool blockForSafetyReason = responseItem.Candidates[0].FinishReason == Candidate.Types.FinishReason.Safety;
            if (blockForSafetyReason)
            {
                fullText.Append("Blocked for safety reasons");
            }
            else
            {
                fullText.Append(responseItem.Candidates[0].Content.Parts[0].Text);
            }
        }

        return fullText.ToString();
    }
}

Go

Before trying this sample, follow the Go setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Go API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import (
	"context"
	"fmt"
	"io"
	"mime"
	"path/filepath"

	"cloud.google.com/go/vertexai/genai"
)

// generateMultimodalContent generates a response into w, based upon the  provided image.
func generateMultimodalContent(w io.Writer, projectID, location, modelName string) error {
	// location := "us-central1"
	// model := "gemini-1.5-flash-001"
	ctx := context.Background()

	client, err := genai.NewClient(ctx, projectID, location)
	if err != nil {
		return fmt.Errorf("unable to create client: %w", err)
	}
	defer client.Close()

	model := client.GenerativeModel(modelName)
	model.SetTemperature(0.4)
	// configure the safety settings thresholds
	model.SafetySettings = []*genai.SafetySetting{
		{
			Category:  genai.HarmCategoryHarassment,
			Threshold: genai.HarmBlockLowAndAbove,
		},
		{
			Category:  genai.HarmCategoryDangerousContent,
			Threshold: genai.HarmBlockLowAndAbove,
		},
	}

	// Given an image file URL, prepare image file as genai.Part
	img := genai.FileData{
		MIMEType: mime.TypeByExtension(filepath.Ext("320px-Felis_catus-cat_on_snow.jpg")),
		FileURI:  "gs://cloud-samples-data/generative-ai/image/320px-Felis_catus-cat_on_snow.jpg",
	}

	res, err := model.GenerateContent(ctx, img, genai.Text("describe this image."))
	if err != nil {
		return fmt.Errorf("unable to generate contents: %w", err)
	}

	fmt.Fprintf(w, "generated response: %s\n", res.Candidates[0].Content.Parts[0])
	return nil
}

Java

Before trying this sample, follow the Java setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Java API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import com.google.cloud.vertexai.VertexAI;
import com.google.cloud.vertexai.api.Candidate;
import com.google.cloud.vertexai.api.GenerateContentResponse;
import com.google.cloud.vertexai.api.GenerationConfig;
import com.google.cloud.vertexai.api.HarmCategory;
import com.google.cloud.vertexai.api.SafetySetting;
import com.google.cloud.vertexai.generativeai.GenerativeModel;
import java.util.Arrays;
import java.util.List;

public class WithSafetySettings {

  public static void main(String[] args) throws Exception {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "your-google-cloud-project-id";
    String location = "us-central1";
    String modelName = "gemini-1.5-flash-001";
    String textPrompt = "your-text-here";

    String output = safetyCheck(projectId, location, modelName, textPrompt);
    System.out.println(output);
  }

  // Use safety settings to avoid harmful questions and content generation.
  public static String safetyCheck(String projectId, String location, String modelName,
      String textPrompt) 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.
    try (VertexAI vertexAI = new VertexAI(projectId, location)) {
      StringBuilder output = new StringBuilder();

      GenerationConfig generationConfig =
          GenerationConfig.newBuilder()
              .setMaxOutputTokens(2048)
              .setTemperature(0.4F)
              .build();

      List<SafetySetting> safetySettings = Arrays.asList(
          SafetySetting.newBuilder()
              .setCategory(HarmCategory.HARM_CATEGORY_HATE_SPEECH)
              .setThreshold(SafetySetting.HarmBlockThreshold.BLOCK_LOW_AND_ABOVE)
              .build(),
          SafetySetting.newBuilder()
              .setCategory(HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT)
              .setThreshold(SafetySetting.HarmBlockThreshold.BLOCK_LOW_AND_ABOVE)
              .build()
      );

      GenerativeModel model = new GenerativeModel(modelName, vertexAI)
          .withGenerationConfig(generationConfig)
          .withSafetySettings(safetySettings);

      GenerateContentResponse response = model.generateContent(textPrompt);
      output.append(response).append("\n");

      // Verifies if the above content has been blocked for safety reasons.
      boolean blockedForSafetyReason = response.getCandidatesList()
          .stream()
          .anyMatch(candidate -> candidate.getFinishReason() == Candidate.FinishReason.SAFETY);
      output.append("Blocked for safety reasons?: ").append(blockedForSafetyReason);

      return output.toString();
    }
  }
}

Node.js

Before trying this sample, follow the Node.js setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Node.js API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

const {
  VertexAI,
  HarmCategory,
  HarmBlockThreshold,
} = require('@google-cloud/vertexai');

/**
 * TODO(developer): Update these variables before running the sample.
 */
const PROJECT_ID = process.env.CAIP_PROJECT_ID;
const LOCATION = 'us-central1';
const MODEL = 'gemini-1.5-flash-001';

async function setSafetySettings() {
  // Initialize Vertex with your Cloud project and location
  const vertexAI = new VertexAI({project: PROJECT_ID, location: LOCATION});

  // Instantiate the model
  const generativeModel = vertexAI.getGenerativeModel({
    model: MODEL,
    // The following parameters are optional
    // They can also be passed to individual content generation requests
    safetySettings: [
      {
        category: HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT,
        threshold: HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
      },
      {
        category: HarmCategory.HARM_CATEGORY_HARASSMENT,
        threshold: HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
      },
    ],
  });

  const request = {
    contents: [{role: 'user', parts: [{text: 'Tell me something dangerous.'}]}],
  };

  console.log('Prompt:');
  console.log(request.contents[0].parts[0].text);
  console.log('Streaming Response Text:');

  // Create the response stream
  const responseStream = await generativeModel.generateContentStream(request);

  // Log the text response as it streams
  for await (const item of responseStream.stream) {
    if (item.candidates[0].finishReason === 'SAFETY') {
      console.log('This response stream terminated due to safety concerns.');
      break;
    } else {
      process.stdout.write(item.candidates[0].content.parts[0].text);
    }
  }
  console.log('This response stream terminated due to safety concerns.');
}

Python

Before trying this sample, follow the Python setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Python API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import vertexai

from vertexai.generative_models import (
    GenerativeModel,
    HarmCategory,
    HarmBlockThreshold,
    Part,
    SafetySetting,
)

# TODO(developer): Update and un-comment below line
# PROJECT_ID = "your-project-id"
vertexai.init(project=PROJECT_ID, location="us-central1")

model = GenerativeModel("gemini-1.5-flash-002")

# Safety config
safety_config = [
    SafetySetting(
        category=HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT,
        threshold=HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
    ),
    SafetySetting(
        category=HarmCategory.HARM_CATEGORY_HARASSMENT,
        threshold=HarmBlockThreshold.BLOCK_LOW_AND_ABOVE,
    ),
]

image_file = Part.from_uri(
    "gs://cloud-samples-data/generative-ai/image/scones.jpg", "image/jpeg"
)

# Generate content
response = model.generate_content(
    [image_file, "What is in this image?"],
    safety_settings=safety_config,
)

print(response.text)
print(response.candidates[0].safety_ratings)
# Example response:
# The image contains a beautiful arrangement of blueberry scones, flowers, coffee, and blueberries.
# The scene is set on a rustic blue background. The image evokes a sense of comfort and indulgence.
# ...

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