Video Stream Data

Dependency-free data structures for video streaming.

Installation

Use pip to install. Its recommended to install in a virtual environment

python3 -m venv video-streaming-pipeline
# install using system-site-packages (like opencv and pyudev)
source video-streaming-pipeline/bin/activate --system-site-packages
pip3 install video_stream_data

Although not recommended a user installation with --break-system-packages would also be okay as it does not have any dependencies.

Usage

Simply import the data classes you want to have, you can use the parser to load the video stream settings from a file (see test/-folder).

You can use the data structure to manually create any kind of video stream.

classDiagram
    direction LR

    class StreamControlType {
        <<enumeration>>
        +INT: str = 'int'
        +BOOL: str = 'bool'
        +MENU: str = 'menu'
    }

    class Encoding {
        <<enumeration>>
        +PASSTHROUGH: str = 'passthrough'
        +BGR: str = 'bgr'
        +GREY: str = 'grey'
        +GREY16: str = 'grey16'
        +GRB: str = 'rbg'
        +BGRA: str = 'bgra'
        +RGBA: str = 'rgba'

    }

    class Codec {
        <<enumeration>>
        +MJPEG: str = 'MJPEG'  # Motion-JPEG
        +YUYV: str = 'YUYV'  # e.g. YUYV 4:2:2
        +XVID: str = 'XVID'  # e.g. mp4 files
        +H264: str = 'H264'
        +UNKNOWN: str = 'unknown'
    }

    class StreamControl {
        +type: StreamControlType
        +name: str
        +writable: bool = False
        +min: float = 0
        +max: float = 0
        +step: int = 1
        +value: float | bool | None = None
        +options: list = []
    }

    class StreamValue {
        # desired video resolution
        +resolution: list[int]
        +fps: float  # desired FPS by user
        # desired configuration
        +controls: dict[str, int | float | bool | None]
        +encoding: Encoding = Encoding.PASSTHROUGH
        +codec: Codec = Codec.UNKNOWN
    }

    class StreamInfo {
        +name: str
        +stream_path: str
        +driver: str
        +codec: list[str]
        +controls: list[StreamControl]
        +resolutions: list[int, int]
        +max_fps: float
        +values: StreamValue
        +backend: str = 'v4l2'
    }

    StreamControlType <|-- StreamControl
    Encoding <|-- StreamValue
    Codec <|-- StreamValue
    StreamControl --> StreamInfo : controls
    StreamValue --> StreamInfo : values

Fig. 1: Data Model for the StreamInfo generated from any device