Amazon Polly Features

Amazon Polly provides an API that enables you to quickly integrate speech synthesis into your application. You simply send the text you want converted into speech to the Amazon Polly API, and Amazon Polly immediately returns the audio stream to your application so your application can begin streaming it directly or store it in a standard audio file format, such as MP3.

Amazon Polly includes dozens of lifelike voices and support for a variety of languages, so you can select the ideal voice and distribute your speech-enabled applications in many countries.

Amazon Polly makes it easy to request an additional stream of metadata that provides information about when particular sentences, words and sounds are being pronounced. Using this metadata stream alongside the synthesized speech audio stream, you can now build your applications with an enhanced visual experience, such as speech-synchronized facial animation or karaoke-style word highlighting.

Please visit the documentation to learn more about how to use Speech Marks. 

With Amazon Polly, you can stream all kinds of information through your application to users in near real time. You can also choose from various sampling rates to optimize bandwidth and audio quality for your application. Amazon Polly supports MP3, Vorbis, and raw PCM audio stream formats.

Amazon Polly supports Speech Synthesis Markup Language (SSML), a W3C standard, XML-based markup language for speech synthesis applications, and supports common SSML tags for phrasing, emphasis, and intonation. This flexibility helps you create lifelike speech that will attract and hold the attention of your audience.

To learn more, visit the Amazon Polly documentation on SSML tags.

Amazon Polly enables you to automatically adjust the speech rate based on a maximum allotted amount of time you define with a feature called time-driven prosody. This is beneficial for many use cases, especially when it comes to localization.

For example, suppose you have US English speech embedded in your training video and want to localize this video into German. Let’s say you translate the text and voice it with Amazon Polly. It is essential that the localized German speech streams in corresponding frames of the video, so the German speech cannot be longer than the US English speech. You can use this feature to more easily facilitate the dubbing process.

Amazon Polly supports all the programming languages included in the Amazon SDK (Java, Node.js, .NET, PHP, Python, Ruby, Go, and C++) and Amazon Mobile SDK (iOS/Android). Polly also supports an HTTP API so you can implement your own access layer.

Amazon Polly can be accessed via the Polly API (and various language-specific SDKs), Amazon Web Services Management Console, and the Amazon command-line interface (CLI). You have full control over all the capabilities of Amazon Polly, whether you use the service through the console, the API, or the CLI.

With Amazon Polly’s custom lexicons, or vocabularies, you can modify the pronunciation of particular words, such as company names, acronyms, foreign words and neologisms (e.g., “ROTFL”, “C’est la vie” when spoken in a non-French voice). To customize these pronunciations, you upload an XML file with lexical entries. For example, you can customize the pronunciation of Nguyen by providing a phoneme using this XML: