Introduction: Leveraging AWS for Real-Time Image Processing

In today’s fast-paced digital world, real-time image processing is crucial for various applications, from security to content moderation. AWS offers services that allow developers to create robust, scalable, and cost-effective serverless image processing pipelines. In this guide, we’ll walk you through building a serverless image processing pipeline on AWS that leverages Amazon S3 for storage, AWS Lambda for processing, Amazon Rekognition for text detection, DynamoDB for storing results, and Amazon SNS for sending notifications.

Step 1: Creating an S3 Bucket for Image Storage

1.1 Accessing AWS S3

Log in to your AWS Management Console and navigate the Amazon S3 service. Amazon S3 is a scalable object storage service perfect for storing the images your pipeline will process.

1.2 Configuring Bucket Settings

Click on “Create bucket” and configure your bucket settings:

  • Bucket Name: Choose a unique name for your bucket.
  • Region: Select the region closest to you.
  • Permissions: Set the permissions according to your security needs. For public-facing applications, you may need to configure access policies accordingly.

After configuring these settings, create the bucket. This bucket will be the entry point for images that trigger the processing pipeline.

Step 2: Setting Up Lambda Functions for Image Processing

2.1 Accessing AWS Lambda

Navigate to the AWS Lambda service in your AWS Management Console. AWS Lambda allows you to run code without provisioning or managing servers, making it ideal for our serverless pipeline.

2.2 Creating a New Lambda Function

Click on “Create function” and select the following options:

  • Author from scratch: Choose this option to create a new Lambda function.
  • Function Name: Give your function a descriptive name like ImageProcessingFunction.
  • Runtime: Select a runtime environment, such as Python or Node.js, depending on your preference.

2.3 Configuring Function Triggers and Code

After creating the function, configure it to trigger whenever a new image is uploaded to the S3 bucket. Under “Function triggers,” select “S3” and choose the bucket you created in Step 1. Add the following code to the Lambda function, ensuring it processes the image:

import boto3

def lambda_handler(event, context):

    # Extract the bucket name and object key from the event

    bucket = event[‘Records’][0][‘s3’][‘bucket’][‘name’]

    key = event[‘Records’][0][‘s3’][‘object’][‘key’]

    

    # Process the image using Amazon Rekognition (to be added in Step 3)

 

Step 3: Integrating Amazon Rekognition for Text Detection

3.1 Enhancing Lambda Code with Rekognition

Amazon Rekognition is a powerful image analysis service that can detect text in images. Enhance your Lambda function by integrating Rekognition:

rekognition = boto3.client(‘rekognition’)

def lambda_handler(event, context):

    bucket = event[‘Records’][0][‘s3’][‘bucket’][‘name’]

    key = event[‘Records’][0][‘s3’][‘object’][‘key’]

    

    # Call Rekognition to detect text in the image

    response = rekognition.detect_text(

        Image={

            ‘S3Object’: {

                ‘Bucket’: bucket,

                ‘Name’: key

            }

        }

    )

    

    # Extract detected text

    detected_text = [text[‘DetectedText’] for text in response[‘TextDetections’]]

    

    # Proceed to store results in DynamoDB (to be covered in Step 4)

Step 4: Storing Results in DynamoDB

4.1 Setting Up a DynamoDB Table

In your AWS Management Console, navigate to DynamoDB and create a new table to store the text detection results:

  • Table Name: Choose a name like ImageTextResults.
  • Primary Key: Set the primary key as ImageID (string).

4.2 Updating Lambda Code for DynamoDB Integration

Update your Lambda function to store the text detection results in DynamoDB:

dynamodb = boto3.client(‘dynamodb’)

def lambda_handler(event, context):

    bucket = event[‘Records’][0][‘s3’][‘bucket’][‘name’]

    key = event[‘Records’][0][‘s3’][‘object’][‘key’]

    

    response = rekognition.detect_text(

        Image={

            ‘S3Object’: {

                ‘Bucket’: bucket,

                ‘Name’: key

            }

        }

    )

    

    detected_text = [text[‘DetectedText’] for text in response[‘TextDetections’]]

    

    # Store the result in DynamoDB

    dynamodb.put_item(

        TableName=’ImageTextResults’,

        Item={

            ‘ImageID’: {‘S’: key},

            ‘DetectedText’: {‘S’: ‘, ‘.join(detected_text)}

        }

    )

Step 5: Sending Notifications with Amazon SNS

5.1 Creating an SNS Topic and Subscription

Navigate to Amazon SNS in the AWS Management Console. Create a new SNS topic for notifications:

  • Topic Name: Name your topic something like ImageProcessingNotifications.

Next, create a subscription to this topic:

  • Protocol: Choose “Email.”
  • Endpoint: Enter the email address where notifications should be sent.

5.2 Incorporating SNS Notifications into Lambda Code

Add SNS integration to your Lambda function to send a notification when text is detected:

sns = boto3.client(‘sns’)

def lambda_handler(event, context):

    bucket = event[‘Records’][0][‘s3’][‘bucket’][‘name’]

    key = event[‘Records’][0][‘s3’][‘object’][‘key’]

    

    response = rekognition.detect_text(

        Image={

            ‘S3Object’: {

                ‘Bucket’: bucket,

                ‘Name’: key

            }

        }

    )

    

    detected_text = [text[‘DetectedText’] for text in response[‘TextDetections’]]

    

    dynamodb.put_item(

        TableName=’ImageTextResults’,

        Item={

            ‘ImageID’: {‘S’: key},

            ‘DetectedText’: {‘S’: ‘, ‘.join(detected_text)}

        }

    )

    

    sns.publish(

        TopicArn=’arn:aws:sns:region:account-id:ImageProcessingNotifications’,

        Message=f’Text detected in image {key}: {“, “.join(detected_text)}’,

        Subject=’Image Processing Notification’

    )

Step 6: Testing the Serverless Image Processing Pipeline

6.1 Uploading Test Images

To test your pipeline, upload a few images containing text to the S3 bucket you created in Step 1. This action will trigger the Lambda function, which will process the photos, detect text, and store the results in DynamoDB.

6.2 Verifying Email Notifications and DynamoDB Results

Check your email inbox for notifications from Amazon SNS. You should receive an email with the detected text. Additionally, you can verify the results in DynamoDB by querying the ImageTextResults table.

Conclusion: A Successful Serverless Image Processing Solution on AWS

Following these steps, you’ve built a fully functional, serverless image processing pipeline on AWS. This pipeline automatically detects text in images, stores the results, and sends notifications—all without manual intervention. This solution can be extended and customized for various use cases, including content moderation, document digitization, etc.

References

Serverless Image Handler on AWS

Field Notes: Building an Automated Image Processing and Model Training Pipeline for Autonomous Driving