Multimedia APIs and Frameworks Overview

Purpose

The Multimedia APIs and Frameworks collection provides a client API consisting of several interfaces that encapsulate a lightweight plug-in framework. The client API enables you to manipulate the audio and video features of the Symbian platform.

Architectural Relationship

The following figure shows the architectural of the components that form the Multimedia APIs and Frameworks collection.

Description

The Multimedia Framework overview details the architecture of the components that constitutes the Multimedia APIs and Frameworks collection.

The Multimedia Subsystem provides the Multimedia capabilities of the Symbian platform. It includes audio recording/playback, video recording/playback, still image conversion and camera control. It includes framework to support these, even if all these functionality are not included. The function inclusion depends on the discretion of the device creator.

Components

The Multimedia APIs and Frameworks constitutes the following components:

• Broadcast Tuner

• Broadcast Transmitter

• Camera API

• Image Conversion Library (ICL)

• Multimedia Framework (MMF)

• Multimedia Utility Library

• Metadata Utility Framework

Broadcast Tuner

The Tuner API is an abstract API for receiving radio broadcasts such as FM or DAB (provided that the necessary hardware is present on the phone). It is intended to provide a consistent API for application developers, that is independent of the underlying implementation and hardware specifics.

Broadcast Transmitter

The FM transmitter is an independent component, which provides control APIs for the applications to control the FM transmitter in a device.

Camera

The Onboard Camera API can be used to achieve video input streaming, and direct screen access can be used to achieve video output streaming. For more information about the Onboard Camera API, see Onboard Camera API Overview.

Image Conversion Library

The Image Conversion Library is a light-weight, client-side plug-in framework for still image codecs. A number of software codecs are shipped with the Symbian platform, most of which are un-optimised, but device creators may replace them with optimised or hardware accelerated versions. The JPEG decoder / encoder has been optimised.

Multimedia Framework

The Multimedia Framework is a light-weight, multi-threaded plug-in framework for handling multimedia data, running as one or more threads in the application process. The only controller plug-in supplied by default is a simple linear audio controller. In turn this supports a number of formats and audio data types. In addition two example controllers are supplied; one for audio (Ogg/Vorbis) and one for video (Avi/XviD).

Multimedia Utility Library

The Multimedia Utility Library provides shared utilities for the MMF.

Metadata Utility Framework

The Metadata Utility Framework provides a plug-in framework for parser plug-ins to extract metadata from audio, video and image files.

Using Multimedia APIs and Frameworks

The Multimedia APIs and Frameworks collection provides cross-platform compatibility for client applications and hardware acceleration plug-in writers, and reduces the cost of porting the applications and codecs between platforms.