Multimedia Controller Overview

The multimedia controller service, mm-control, listens through the Persistent Publish/Subscribe (PPS) service for commands sent by media applications and then invokes the appropriate platform components to carry out the requested media operations.

The mm-control service provides a middle layer between the car system's HMI and the lower-level multimedia services that access media content on devices and manage playback. By providing this middle layer, the QNX CAR platform abstracts several components into one controller that supports many types of media operations.

HMI applications can write media commands (encoded as JSON objects) into the PPS control object monitored by mm-control and then read the results of those commands through the same PPS object, after mm-control has processed those commands.

The QNX CAR platform includes the following components (multimedia services) that continuously listen for and execute commands forwarded by mm-control: