Generate text from multimodal prompt

This sample demonstrates how to generate text from a multimodal prompt using the Gemini model. The prompt consists of three images and two text prompts. The model generates a text response that describes the images and the text prompts.

Code sample

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.genai.Client;
import com.google.genai.types.Content;
import com.google.genai.types.GenerateContentResponse;
import com.google.genai.types.HttpOptions;
import com.google.genai.types.Part;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;

public class TextGenerationWithMultiLocalImage {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String modelId = "gemini-2.5-flash";
    String localImageFilePath1 = "your/local/img1.jpg";
    String localImageFilePath2 = "your/local/img2.jpg";
    generateContent(modelId, localImageFilePath1, localImageFilePath2);
  }

  // Generates text using multiple local images
  public static String generateContent(
      String modelId, String localImageFilePath1, String localImageFilePath2) throws IOException {
    // 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 (Client client =
        Client.builder()
            .location("global")
            .vertexAI(true)
            .httpOptions(HttpOptions.builder().apiVersion("v1").build())
            .build()) {

      // Read content from local files.
      byte[] localFileImg1Bytes = Files.readAllBytes(Paths.get(localImageFilePath1));
      byte[] localFileImg2Bytes = Files.readAllBytes(Paths.get(localImageFilePath2));

      GenerateContentResponse response =
          client.models.generateContent(
              modelId,
              Content.fromParts(
                  Part.fromBytes(localFileImg1Bytes, "image/jpeg"),
                  Part.fromBytes(localFileImg2Bytes, "image/jpeg"),
                  Part.fromText("Generate a list of all the objects contained in both images")),
              null);

      System.out.print(response.text());
      // Example response:
      // Based on both images, here are the objects contained in both:
      //
      // 1.  **Coffee cups (or mugs)**: Both images feature one or more cups containing a beverage.
      // 2.  **Coffee (or a similar beverage)**: Both images contain a liquid beverage in the cups,
      // appearing to be coffee or a coffee-like drink.
      // 3.  **Table (or a flat surface)**: Both compositions are set on a flat surface, likely a
      // table or countertop.
      return response.text();
    }
  }
}

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 fs = require('fs');

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

function loadImageAsBase64(path) {
  const bytes = fs.readFileSync(path);
  return bytes.toString('base64');
}

async function generateContent(
  projectId = GOOGLE_CLOUD_PROJECT,
  location = GOOGLE_CLOUD_LOCATION,
  imagePath1,
  imagePath2
) {
  const ai = new GoogleGenAI({
    vertexai: true,
    project: projectId,
    location: location,
  });

  // TODO(Developer): Update the below file paths to your images
  const image1 = loadImageAsBase64(imagePath1);
  const image2 = loadImageAsBase64(imagePath2);

  const response = await ai.models.generateContent({
    model: 'gemini-2.5-flash',
    contents: [
      {
        role: 'user',
        parts: [
          {
            text: 'Generate a list of all the objects contained in both images.',
          },
          {
            inlineData: {
              data: image1,
              mimeType: 'image/jpeg',
            },
          },
          {
            inlineData: {
              data: image2,
              mimeType: 'image/jpeg',
            },
          },
        ],
      },
    ],
  });

  console.log(response.text);

  return response.text;
}
// Example response:
//  Okay, here's a jingle combining the elements of both sets of images, focusing on ...
//  ...

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"))
# TODO(Developer): Update the below file paths to your images
# image_path_1 = "path/to/your/image1.jpg"
# image_path_2 = "path/to/your/image2.jpg"
with open(image_path_1, "rb") as f:
    image_1_bytes = f.read()
with open(image_path_2, "rb") as f:
    image_2_bytes = f.read()

response = client.models.generate_content(
    model="gemini-2.5-flash",
    contents=[
        "Generate a list of all the objects contained in both images.",
        Part.from_bytes(data=image_1_bytes, mime_type="image/jpeg"),
        Part.from_bytes(data=image_2_bytes, mime_type="image/jpeg"),
    ],
)
print(response.text)
# Example response:
# Okay, here's a jingle combining the elements of both sets of images, focusing on ...
# ...

What's next

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