Camel Webcam component

Camel Webcam component can be used to capture still images and detect motion. With Camel Webcam you can connect a camera to your device's USB port, or install the camera mod on the Raspberry Pi board for example, and poll for an image periodically and respond to motion events. The body of the message is the current image as a BufferedInputStream, while motion events are stored in the header io.rhiot.webcam.webcamMotionEvent. This event may be useful for getting the image captured prior to the motion event, as well the Points where the motion occurred and the center of motion gravity.

Maven dependency

Maven users should add the following dependency to their POM file:

io.rhiotcamel-webcam${rhiot.version}

Avaliable for rhiot.version >= 0.1.2

URI format

The Camel endpoint URI format for the Webcam consumer is as follows:

webcam:label

Where label can be replaced with any text label:

from("webcam:spycam").
  to("file:///var/spycam");

This route creates a scheduled consumer taking 1 frame per second and writes it to file in the PNG format.

Alternatively, respond to motion events by setting the endpoint parameter 'motion' to true.

from("webcam:spycam?motion=true").
  to("file:///var/spycam");

You can also poll the webcam for a single image, for example;

from("jms:webcam").
  to("webcam:spycam");

Specify the resolution with custom width and height, or the resolution name;

from("webcam:spycam?resolution=HD720").
  to("seda:cam")

Options

Option	Default value	Description
consumer.deviceName		Specify the webcam device name, if absent the first device available is used, eg /dev/video0.
consumer.format	PNG	Capture format, one of 'PNG,GIF,JPG'
consumer.initialDelay	1000	Milliseconds before the polling starts. Applies only to scheduled consumers.
consumer.motion	false	Whether to listen for motion events.
consumer.motionInterval	500	Interval in milliseconds to detect motion.
consumer.pixelThreshold	25	Intensity threshold when motion is detected (0 - 255)
consumer.areaThreshold	0.2	Percentage threshold of image covered by motion (0 - 100)
consumer.motionInertia	-1 (2 * motionInterval)	Motion inertia (time when motion is valid)
consumer.resolution	QVGA	Resolution to use (PAL, HD720, VGA etc)
consumer.width	320	Resolution width, note that resolution takes precendence.
consumer.height	240	Resolution height, note that resolution takes precendence.
consumer.delay	1000	Delay in milliseconds. Applies only to scheduled consumers.
consumer.useFixedDelay	false	Set to true to use a fixed delay between polls, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details.

Process manager

Process manager is also used by the Webcam component to execute Linux commands responsible for starting the webcam driver and configuring the image format and resolution. If for some reason you would like to change the default implementation of the process manager used by Camel (i.e. io.rhiot.utils.process.DefaultProcessManager), you can set it on the component level:

WebcamComponent webcam = new WebcamComponent();
webcam.setProcessManager(new CustomProcessManager());
camelContext.addComponent("webcam", webcam);

If custom process manager is not set on the component, Camel will try to find the manager instance in the registry. So for example for Spring application, you can just configure the manager as the bean:

@Bean
ProcessManager myProcessManager() {
    new CustomProcessManager();
}

Custom process manager may be useful if your Linux distribution or camera requires executing some unusual commands in order to load the v4l2 (Video for Linux) module.

Installer

For some Linux+webcam combinations, the webcam component requires v4l-utils and its dependencies to be installed on an operating system. By default the Webcam component installs v4l-utils using apt-get, you can configure the installer or set an alternate one on the component:

WebcamComponent webcam = new WebcamComponent();
webcam.setInstaller(new BrewInstaller());
camelContext.addComponent("webcam", webcam);    

You can also specify alternate dependencies for your platform, if your platform uses my-custom-v4l-utils, configure the component as follows:

WebcamComponent webcam = new WebcamComponent();
webcam.setRequiredPackages("my-custom-v4l-utils");  //comma-separated list of packages to install
camelContext.addComponent("webcam", webcam);    

If an Installer is not set on the component, Camel will try to find an instance in the registry. So for example for Spring application, you can configure the installer as a bean:

@Bean
Installer myInstaller() {
    CustomInstaller installer = new CustomInstaller();
    installer.setTimeout(60000 * 10); //Allow up to 10 minutes to install packages
}

By default an installer ignores problems with the webcam packages installation and only logs the warning using a logger WARN message. If you would like the component to thrown an exception instead of logging a message, set ignoreInstallerProblems property of the WebcamComponent to true:

WebcamComponent webcam = new WebcamComponent();
webcam.setIgnoreInstallerProblems(true);
camelContext.addComponent("webcam", webcam);