The NDK package includes an Android-specific implementation of the OpenSL ES™ API specification from the Khronos Group. This library allows you to use C or C++ to implement high-performance, low-latency audio, whether you are writing a synthesizer, digital audio workstation, karaoke, game, or other real-time app.
This section begins by providing some basic information about the API, including typical use cases and how to incorporate it into your app. It then explains what you need to know about the Android-specific implementation of OpenSL ES, focusing on the differences between this implementation and the reference specification. Next, you'll learn how to minimze input latency when using built-in or external microphones and some actions that you can take to minimize output latency. It describes the reasons that you should use floating-point numbers to represent your audio data, and it provides information that will help you choose the optimal sample rate. This section concludes with some supplemental programming notes to ensure proper implementation of OpenSL ES.