Say Cheese!

A minimal library for integrating webcam snapshots into your app. It uses getUserMedia, a recent API for accessing audio and video in the browser.

Demo

Setup

Grab the JS, host it, and add it to your page. For example:

<script src='/assets/js/say-cheese.js'></script>

Usage

Say Cheese exposes a minimal, event based API:

var sayCheese = new SayCheese('#container-element', { snapshots: true });

sayCheese.on('start', function() {
 // do something when started
 this.takeSnapshot();
});

sayCheese.on('error', function(error) {
 // handle errors, such as when a user denies the request to use the webcam,
 // or when the getUserMedia API isn't supported
});

sayCheese.on('snapshot', function(snapshot) {
  // do something with a snapshot canvas element, when taken
});

sayCheese.start();

Taking snapshots

You can take a snapshot at any time after initialisation, by calling takeSnapshot():

sayCheese.on('snapshot', function(snapshot) {
  // do something with the snapshot
});

sayCheese.takeSnapshot();

If you need to change the size of the snapshot created, pass in the new width and height as arguments:

var width = 640, height = 480;
sayCheese.takeSnapshot(width, height);

It defaults to the full size of the video (generally 640x480) if the arguments are omitted.

I don't want snapshots; just give me the video!

No problem. Just disable it when you first create the instance:

var sayCheese = new SayCheese('#container-element', { snapshots: false });

Note that when you do this, takeSnapshot() will not do anything.

Stopping the show

There's also a function to stop the webcam after loading it up:

sayCheese.on('stop', function() {
  // do something when it's stopped
});

sayCheese.stop();

Audio support

Audio's disabled by default, because it doesn't have full browser support. You can still enable it for browsers that do support it, though. Just set audio to true when setting up.

var sayCheese = new SayCheese('#container-element', { audio: true });

This will request access to the microphone, and will currently pipe the audio through to your output device.

This is supported on the desktop in:

• Google Chrome
• Firefox 25+
• Latest Opera

Mobile device support is untested, so your mileage may vary.

Resources, things using Say Cheese, etc.

getUserMedia on the server, with Sinatra and Say Cheese

If you have any useful resources, or things you did with Say Cheese that you think should be shown off, by all means open a pull request or an issue or whatever.

Tests

Some basic tests cover the callback functionality. They were written to be run in a browser that supports the getUserMedia API. Due to the nature of that API, there is no automation for allowing or denying the request, so it has to be done manually for each one.

Compatibility

Tested and verified to work in:

• Firefox
• Google Chrome
• Opera

License

Copyright (C) 2012 Lee Machin

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.