# Return binary media from a Lambda proxy integration in API Gateway
<a name="lambda-proxy-binary-media"></a>

To return binary media from an [AWS Lambda proxy integration](set-up-lambda-proxy-integrations.md), base64 encode the response from your Lambda function. You must also [configure your API's binary media types](api-gateway-payload-encodings-configure-with-console.md). When you configure your API's binary media types, your API treats that content type as binary data. The payload size limit is 10 MB.

**Note**  
To use a web browser to invoke an API with this example integration, set your API's binary media types to `*/*`. API Gateway uses the first `Accept` header from clients to determine if a response should return binary media. To return binary media when you can't control the order of `Accept` header values, such as requests from a browser, set your API's binary media types to `*/*` (for all content types).

The following example Lambda function can return a binary image from Amazon S3 or text to clients. The function's response includes a `Content-Type` header to indicate to the client the type of data that it returns. The function conditionally sets the `isBase64Encoded` property in its response, depending on the type of data that it returns.

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#### [ Node.js ]

```
import { S3Client, GetObjectCommand } from "@aws-sdk/client-s3"

const client = new S3Client({region: 'us-east-2'});

export const handler = async (event) => {

  var randomint = function(max) {
    return Math.floor(Math.random() * max);
  }
  var number = randomint(2);
  if (number == 1){ 
    const input = {
      "Bucket" : "bucket-name",
      "Key" : "image.png"
      }
    try {
      const command = new GetObjectCommand(input)
      const response = await client.send(command);
      var str = await response.Body.transformToByteArray();
    } catch (err) {
      console.error(err);
    }
    const base64body = Buffer.from(str).toString('base64');
    return {
      'headers': { "Content-Type": "image/png" },
      'statusCode': 200,
      'body': base64body,
      'isBase64Encoded': true
      }
    } else {
        return {
        'headers': { "Content-Type": "text/html" },
        'statusCode': 200,
        'body': "<h1>This is text</h1>",
        }
    }
}
```

------
#### [ Python ]

```
import base64
import boto3
import json
import random

s3 = boto3.client('s3')

def lambda_handler(event, context):
    number = random.randint(0,1)
    if number == 1:
        response = s3.get_object(
            Bucket='bucket-name',
            Key='image.png',
        )
        image = response['Body'].read()
        return {
            'headers': { "Content-Type": "image/png" },
            'statusCode': 200,
            'body': base64.b64encode(image).decode('utf-8'),
            'isBase64Encoded': True
        }
    else:
        return {
            'headers': { "Content-type": "text/html" },
            'statusCode': 200,
            'body': "<h1>This is text</h1>",
        }
```

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To learn more about binary media types, see [Binary media types for REST APIs in API Gateway](api-gateway-payload-encodings.md).