4.5 - AWS AI and machine learning services
AWS Certified Cloud Practitioner covers the AI and machine learning services and what each does. Amazon SageMaker is the platform that lets developers build, train and deploy custom machine learning models end to end. The pre-trained AI services solve specific tasks without ML expertise: Amazon Rekognition analyses images and videos to detect objects, faces and text; Amazon Comprehend uses natural language processing to find insights and sentiment in text; and Amazon Polly converts written text into natural-sounding speech (text-to-speech). Others include Transcribe (speech to text), Translate and Lex (chatbots). You should match a described AI task to the right managed service. Expect scenario questions that describe building a custom model, analysing images, extracting sentiment from text, or generating speech, and ask which AWS AI/ML service - SageMaker, Rekognition, Comprehend or Polly - fits the need.
Build/train/deploy custom ML models = SageMaker. Analyse images/videos (objects, faces, text) = Rekognition. NLP sentiment/insights in text = Comprehend. Text to natural speech = Polly.
Practice questions
1. Which service lets developers build, train, and deploy machine learning models?
- Amazon SageMaker (correct answer)
- Amazon SNS
- Amazon CloudFront
- Amazon Textract
Amazon SageMaker is the managed platform to build, train, and deploy ML models at scale. The other options are messaging, content delivery, and document text extraction.
2. Which AI service analyzes images and videos to detect objects, faces, and text?
- Amazon Comprehend
- Amazon Rekognition (correct answer)
- Amazon Polly
- Amazon Translate
Amazon Rekognition performs image and video analysis: object/scene detection, face analysis, and text in images. Comprehend is for text/NLP, Polly is text-to-speech, Translate translates.
3. Which service uses natural language processing to find insights and sentiment in text?
- Amazon Rekognition
- Amazon Polly
- Amazon Comprehend (correct answer)
- Amazon Transcribe
Amazon Comprehend is an NLP service that extracts entities, key phrases, language, and sentiment from text. Rekognition is vision, Polly is text-to-speech, Transcribe is speech-to-text.
4. Which service converts written text into natural-sounding speech (text-to-speech)?
- Amazon Polly (correct answer)
- Amazon Transcribe
- Amazon Kendra
- Amazon SQS
Amazon Polly turns text into lifelike speech (text-to-speech). Its opposite is Transcribe, which turns speech into text. Kendra is enterprise search; SQS is a queue.
5. Which service transcribes audio into text (speech-to-text), for example captioning calls?
- Amazon Polly
- Amazon Translate
- Amazon Comprehend
- Amazon Transcribe (correct answer)
Amazon Transcribe converts speech to text (transcription/captions). Polly is the reverse (text-to-speech), Translate converts between languages, Comprehend analyzes text meaning.
6. Which service builds conversational chatbots using voice and text?
- Amazon Translate
- Amazon Lex (correct answer)
- Amazon Textract
- Amazon Rekognition
Amazon Lex provides the speech recognition and natural language understanding to build chatbots and voice assistants (the same technology behind Alexa). Translate handles languages, Textract extracts document text.