1# Multimedia<a name="EN-US_TOPIC_0000001078026808"></a> 2 3- [Introduction](#section11660541593) 4- [Directory Structure](#section161941989596) 5- [Constraints](#section119744591305) 6- [Usage Guidelines](#section1312121216216) 7- [Installation](#section11914418405) 8- [Repositories Involved](#section1371113476307) 9 10## Introduction<a name="section11660541593"></a> 11 12The multimedia subsystem provides a set of simple and easy-to-use APIs for you to access the system and media resources. 13 14This subsystem offers various media services covering audio, videos, and cameras, which provide the following capabilities: 15 16- Audio playback and recording 17- Video playback and recording 18 19- Photographing and recording \(with cameras\) 20 21## Architecture<a name="section11660541594"></a> 22 23**Figure 1** Common architecture of the multimedia subsystem<a name="fig13371156141412"></a> 24 25 26 27 28**Figure 2** Architecture of the multimedia subsystem suitable for the small system<a name="fig866802061417"></a> 29 30 31 32 33**Figure 3** Multimedia service flow for the small system<a name="fig1334042801419"></a> 34 35 36## Directory Structure<a name="section161941989596"></a> 37 38The structure of the repository directory is as follows: 39 40``` 41/foundation/multimedia # Service code 42├── audio_lite # Audio module for the small system 43│ ├── figures # Architecture and process figures of the audio module for the small system 44│ ├── frameworks # Audio framework implementation for the small system 45│ └── interfaces # Audio module APIs for the small system 46├── audio_standard # Audio module for the standard system 47│ ├── figures # Architecture and process figures of the audio module for the standard system 48│ ├── frameworks # Audio framework implementation for the standard system 49│ ├── interfaces # Audio module APIs for the standard system 50│ ├── sa_profile # Audio service profile for the standard system 51│ └── services # Audio service implementation for the standard system 52├── camera_lite # Camera module for the small system 53│ ├── figures # Architecture and process figures of the camera module for the small system 54│ ├── frameworks # Camera framework implementation for the small system 55│ └── interfaces # Camera module APIs for the small system 56├── camera_standard # Camera module for the standard system 57│ ├── figures # Architecture and process figures of the camera module for the standard system 58│ ├── frameworks # Camera framework implementation for the standard system 59│ └── interfaces # Camera module APIs for the standard system 60├── media_lite # Playback and recording module for the small system 61│ ├── figures # Architecture and process figures of the playback and recording module for the small system 62│ ├── frameworks # Playback and recording framework implementation for the small system 63│ ├── interfaces # Playback and recording module APIs for the small system 64│ └── services # Playback and recording service implementation for the small system 65├── media_standard # Playback and recording module for the standard system 66│ ├── figures # Architecture and process figures of the playback and recording module for the standard system 67│ ├── frameworks # Playback and recording framework implementation for the standard system 68│ └── interfaces # Playback and recording module APIs for the standard system 69└── utils # Subsystem utility module 70 └── lite # Utility module for the small system 71 ├── figures # Architecture and process figures of the utility module for the small system 72 ├── hals # Hardware abstraction interfaces of the subsystem for the small system 73 ├── interfaces # Utility module APIs for the standard system 74 └── src # Utility module framework implementation for the small system 75``` 76 77## Constraints<a name="section119744591305"></a> 78 79Hardware-based decoding and encoding functions of audio and video data are device-specific. 80 81## Usage Guidelines<a name="section1312121216216"></a> 82 83You can use the APIs in any of the provided classes based on your development requirements. 84 85- For details about how to call media APIs to implement the video recording, preview, and playback, see [Multimedia Development Guide](https://gitee.com/openharmony/docs/blob/master/en/device-dev/subsystems/subsys-multimedia.md). 86- For a simple player, use **Player** and **Recorder** classes to quickly implement the playback and recording features. 87- The **CameraKit** class provides a group of effective methods for controlling a camera, which facilitates the camera development. 88- You can create a **CameraKit** object and register various callbacks to respond to many events in the multimedia module. Then, create a **Camera** object to operate camera resources, for example, to start preview, recording, and stream capturing, and set related parameters. 89 90## Installation<a name="section11914418405"></a> 91 92Load the kernel and related drivers before installing the repository. For details, see readme files of kernel and driver subsystems. 93 94## Repositories Involved<a name="section1371113476307"></a> 95 96[multimedia\_camera\_lite](https://gitee.com/openharmony/multimedia_camera_lite) 97 98[multimedia\_audio\_lite](https://gitee.com/openharmony/multimedia_audio_lite) 99 100[multimedia\_media\_lite](https://gitee.com/openharmony/multimedia_media_lite) 101 102[multimedia\_utils\_lite](https://gitee.com/openharmony/multimedia_utils_lite) 103 104[multimedia\_camera\_standard](https://gitee.com/openharmony/multimedia_camera_standard) 105 106[multimedia\_audio\_standard](https://gitee.com/openharmony/multimedia_audio_standard) 107 108[multimedia\_media\_standard](https://gitee.com/openharmony/multimedia_media_standard) 109 110
