USB Camera Manager for Ruff

This package manages all of the cameras with USB interfae that is compatible with the protocol of UVC(USB Video Class).

This package has two parts: one is the camera manager and the other is the driver of camera.

The camera manager supplies the mount or unomut events when camera is plugged into or unplugged from the system.

The driver of camera supplies some specific functions.

Supported Engines

• Ruff: >=1.5.0 <2.0.0

Installing

Execute following command to install.

rap install ruff-v1-usb-camera-manager

Usage

Here is the basic usage of this driver.

Example 1

Specify the resolution when invoke the method of camera.

var CameraManager = require('ruff-v1-usb-camera-manager');
var cameraManager = new CameraManager();
$('#usb').install(cameraManager);
cameraManager.on('mount', function (camera) {
    // camera is mounted
    var picture1 = camera.capture({
        width: 800,
        height: 600
    });

    picture1.on('data', function (data) {
        // JPEG format data
        // ...
    });

    picture1.on('end', function () {
        // ...
    });

    var picture2 = camera.capture({
        width: 320,
        height: 240
    });

    picture2.on('data', function (data) {
        // JPEG format data
        // ...
    });

    picture2.on('end', function () {
        // ...
    });


});

cameraManager.on('unmount', function (camera) {
    // camera is unmounted
});

Example 2

Specify the resolution when instance the camera manager.

var CameraManager = require('ruff-v1-usb-camera-manager');
var options = {
    resolution: {
        width: 800,
        height: 600
    }
}
var cameraManager = new CameraManager(options);

$('#usb').install(cameraManager);
cameraManager.on('mount', function (camera) {
    // camera is mounted
    var picture = camera.capture();

    picture.on('data', function (data) {
        // JPEG format data
        // ...
    });

    picture.on('end', function () {
        // ...
    });
});

cameraManager.on('unmount', function (camera) {
    // camera is unmounted
});

Manager API References

Methods

CameraManager(options)

Exported by this module, it is the constructor method.

• options: It is arguments passed to instance one object of Camera, you can set the resolution property, for example:

{
    resolution: {
        width: 800,
        height: 600
    }
}

Events

mount

The mount event informs that one usb camera is plugged into the system.

unmount

The unmount event informs that one usb camera is plugged from the system.

Camera API References

Methods

capture([resolution][, callback])

Capture a picture and return an object which emits data and end events.

• resolution: It is an object which contains width and height properties, i.e. the resolution is widthxheight. Due to memory limitation, the resolution must be less than 1280x720. If you set some resolution that is not supported by the camera, this driver will change your setting to one supported resolution.

• callback: No argument other than a possible error is given to the completion callback. The callback will be invoked when the capture operation is finished.

Both resolution and callback are optional parameters. The default resolution is 320x240.

Events

data

The data event supplies the data of captured picture with JPEG format.

end

The end event informs the data of captured picture is ended.

Contributing

Contributions to this project are warmly welcome. But before you open a pull request, please make sure your changes are passing code linting and tests.

You will need the latest Ruff SDK to install rap dependencies and then to run tests.

Installing Dependencies

npm install
rap install

Running Tests

npm test

License

The MIT License (MIT)

Copyright (c) 2016 Nanchao Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.