MediaRecorder

MediaRecorder is a software interface used to record multimedia data from input sources such as microphones, cameras, or composed media streams. The term is used in multiple platforms, most notably as a web API for browsers and as a native Android API. Each implementation provides a different set of controls and encoders, but both share the goal of producing a media file or blob from live input.

In web browsers, the MediaRecorder interface records a MediaStream created by APIs like getUserMedia. Applications call start, stop, pause, and resume, and receive media data in chunks through the ondataavailable event as Blob objects. The encoded format is determined by the mimeType and available codecs, which vary by browser. Developers can specify options such as audioBitsPerSecond and videoBitsPerSecond in the constructor or via the track settings. Recording typically runs in a secure context and may require user permission.

In Android, the android.media.MediaRecorder class records audio and video to a file or stream. The typical setup involves selecting a video and/or audio source, setting an output format and corresponding encoders, and designating an output file. The workflow is prepare, start, stop, and release, with error handling during preparation. Permissions such as RECORD_AUDIO and CAMERA are required, along with appropriate storage permissions on older Android versions. Supported codecs and formats depend on device hardware and OS version.

Both implementations require proper handling of lifecycle, resource management, and performance considerations, including buffering and encoding settings. Compatibility varies across browsers and devices, so feature checks and fallbacks are common. MediaRecorder enables applications to capture user-generated content, demonstrations, or streaming samples for offline or remote use. See also Web MediaRecorder API, getUserMedia, and android.media.MediaRecorder.