Generate text using images from a local and Google Cloud Storage

This example demonstrates how to generate text using a local image and an image in Google Cloud Storage

Explore further

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

Code sample

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"
	"os"

	genai "google.golang.org/genai"
)

// generateWithMultiImg shows how to generate text using multiple image inputs.
func generateWithMultiImg(w io.Writer) error {
	ctx := context.Background()

	client, err := genai.NewClient(ctx, &genai.ClientConfig{
		HTTPOptions: genai.HTTPOptions{APIVersion: "v1"},
	})
	if err != nil {
		return fmt.Errorf("failed to create genai client: %w", err)
	}

	// TODO(Developer): Update the path to file (image source:
	//   https://storage.googleapis.com/cloud-samples-data/generative-ai/image/latte.jpg )
	imageBytes, err := os.ReadFile("./latte.jpg")
	if err != nil {
		return fmt.Errorf("failed to read image: %w", err)
	}

	contents := []*genai.Content{
		{Parts: []*genai.Part{
			{Text: "Write an advertising jingle based on the items in both images."},
			{FileData: &genai.FileData{
				// Image source: https://storage.googleapis.com/cloud-samples-data/generative-ai/image/scones.jpg
				FileURI:  "gs://cloud-samples-data/generative-ai/image/scones.jpg",
				MIMEType: "image/jpeg",
			}},
			{InlineData: &genai.Blob{
				Data:     imageBytes,
				MIMEType: "image/jpeg",
			}},
		}},
	}
	modelName := "gemini-2.0-flash-001"

	resp, err := client.Models.GenerateContent(ctx, modelName, contents, nil)
	if err != nil {
		return fmt.Errorf("failed to generate content: %w", err)
	}

	respText, err := resp.Text()
	if err != nil {
		return fmt.Errorf("failed to convert model response to text: %w", err)
	}
	fmt.Fprintln(w, respText)

	// Example response:
	// Okay, here's an advertising jingle inspired by the blueberry scones, coffee, flowers, chocolate cake, and latte:
	//
	// (Upbeat, jazzy music)
	// ...

	return nil
}

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 {GoogleGenAI} = require('@google/genai');

const GOOGLE_CLOUD_PROJECT = process.env.GOOGLE_CLOUD_PROJECT;
const GOOGLE_CLOUD_LOCATION = process.env.GOOGLE_CLOUD_LOCATION || 'global';

async function generateContent(
  projectId = GOOGLE_CLOUD_PROJECT,
  location = GOOGLE_CLOUD_LOCATION
) {
  const ai = new GoogleGenAI({
    vertexai: true,
    project: projectId,
    location: location,
  });

  const image1 = {
    fileData: {
      fileUri: 'gs://cloud-samples-data/generative-ai/image/scones.jpg',
      mimeType: 'image/jpeg',
    },
  };

  const image2 = {
    fileData: {
      fileUri: 'gs://cloud-samples-data/generative-ai/image/fruit.png',
      mimeType: 'image/png',
    },
  };

  const response = await ai.models.generateContent({
    model: 'gemini-2.0-flash',
    contents: [
      image1,
      image2,
      'Generate a list of all the objects contained in both images.',
    ],
  });

  console.log(response.text);

  return response.text;
}

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. 

from google import genai
from google.genai.types import HttpOptions, Part

client = genai.Client(http_options=HttpOptions(api_version="v1"))

# Read content from GCS
gcs_file_img_path = "gs://cloud-samples-data/generative-ai/image/scones.jpg"

# Read content from a local file
with open("test_data/latte.jpg", "rb") as f:
    local_file_img_bytes = f.read()

response = client.models.generate_content(
    model="gemini-2.5-flash-preview-05-20",
    contents=[
        "Generate a list of all the objects contained in both images.",
        Part.from_uri(file_uri=gcs_file_img_path, mime_type="image/jpeg"),
        Part.from_bytes(data=local_file_img_bytes, mime_type="image/jpeg"),
    ],
)
print(response.text)
# Example response:
# Okay, here's the list of objects present in both images:
# ...

What's next

To search and filter code samples for other Google Cloud products, see the Google Cloud sample browser.