SCD.js

Pixel based video scene change detection in JavaScript.

Fast, lightweight (only 1.4k gzipped) and easy to use.

Try it here: http://gmarty.github.com/SCD.js/

How to make it work?

Call Scd() passing it an HTML video element:

var videoEl = document.getElementById('myVideo');
Scd(videoEl);
videoEl.play(); // Start the video

When a new cut change is detected, the video element will fire a scenechange event that you can easily listen to:

videoEl.addEventListener('scenechange', function(e) {
  console.log('New scene change detected at', e.timeStamp);
});

How to configure it?

To specify particular settings, you can pass an object of parameters:

Scd(videoEl, {
  mode: 'PlaybackMode',
  step_width: 50,
  step_height: 37
});

Available options

step_width and step_height allow you to specify the size of the thumbnail image from which pixel differences will be computed when determining scene changes. If it's high, it will require more processing time. If it's low, it will lead to less precise results. Alternatively, you can set both width and height at a time using step.

Scene detection can be run in 2 different modes:

• FastForwardMode scans the video for scene changes as fast as it can.
• If mode is set to PlaybackMode, the scene will be detected as the video plays.

FastForwardMode is the default.

You can adjust the minimum time frame in which a scene change cannot happen by giving a value in seconds to minSceneDuration. By default it is 0.25. If your video is likely to have long fading transitions of let's say 0.75 seconds, you should give minSceneDuration a value of at least 0.75. Otherwise, several scene changes might be detected during the fading.

threshold is a number between 0 and 100 and has a default value of 25. If the difference between 2 scanned images is above threshold%, then a cut scene is detected. For black and white videos you'll probably want to lower this value to about 0.15. threshold is the sensitivity of the scene change detection.

Callback function

The constructor accepts a third argument which is a callback function called at the end of the video:

Scd(videoEl, {
  mode: 'PlaybackMode',
}, function(sceneTimecodes){
  console.log(sceneTimecodes.join(', '));
});

It returns an array containing the time codes in seconds of the scene changes detected relatively to the beginning of the video.

Note

SCD.js is subject to same domain policy and only works for video hosted on the same domain.

License

Copyright 2012 Guillaume Marty

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.