thumbnails-webvtt

Video thumbnails + WebVTT using Node.js

Thumbnails generator module. Uses WebVTT as thumbnails descriptor. Can pack thumbnails into spritesheet using node-sprit module.

Installation

npm install thumbnails-webvtt --save

Requirements

• ffmpeg used by fluent-ffmpeg
• ImageMagick as used by node-sprite

Example

'use strict'
 
var thumbgen = require('thumbnails-webvtt')
 
thumbgen('/media/Hammer.of.the.Gods.2013.BluRay.720p.mkv', {
  output:          '/vtt/Hammer.of.the.Gods.2013.BluRay.720p.vtt',
  size:            {
    width: 480
  },
  numThumbnails:   6,
  spritesheet:     true
}, function(err, metadata) {
  if (err) {
    throw err
  }
  
  console.dir(metadata)
})

will print

[ { path: '/Hammer.of.the.Gods.2013.BluRay.720p/thumbnails.png#xywh=0,808,480,200',
    from: '00:00:00.000',
    to: '00:14:49.474' },
  { path: '/Hammer.of.the.Gods.2013.BluRay.720p/thumbnails.png#xywh=0,0,480,200',
    from: '00:14:49.474',
    to: '00:29:38.947' },
  { path: '/Hammer.of.the.Gods.2013.BluRay.720p/thumbnails.png#xywh=0,202,480,200',
    from: '00:29:38.947',
    to: '00:44:28.421' },
  { path: '/Hammer.of.the.Gods.2013.BluRay.720p/thumbnails.png#xywh=0,404,480,200',
    from: '00:44:28.421',
    to: '00:59:17.894' },
  { path: '/Hammer.of.the.Gods.2013.BluRay.720p/thumbnails.png#xywh=0,606,480,200',
    from: '00:59:17.894',
    to: '01:14:07.368' },
  { path: '/Hammer.of.the.Gods.2013.BluRay.720p/thumbnails.png#xywh=0,1010,480,200',
    from: '01:14:07.368',
    to: '01:38:49.824' } ]

API

thumbgen(source, options, callback)

Create thumbnails (and optionally pack them into spritesheet) and create WebVTT file for file(s). Options are described below

Options

• output defaults to "SOURCE_DIR/SOURCE_BASENAME.vtt"

  • WebVTT filename

• assetsDirectory defaults to "SOURCE_BASENAME"

  • Name of folder which keeps thumbnails or spritesheet.

• size defaults to null

  • Size of generated thumbnails. If not specified original video stream width and height will be used. If only width or height is specified other will be computed according to source video ratio.

• size.width defaults to SOURCE_WIDTH

  • Read above

• size.height defaults to SOURCE_HEIGHT

  • Read above

• timemarks defaults to null

  • Array with timemarks in seconds. E.g. ['123.123', '345.345']

• numThumbnails defaults to 0

  • Number of thumbnails to generate. Used in opposite to timemarks. Each thumbnail moment is calculated as source_duration * 0.9 / numThumbnails.

• secondsPerThumbnail defaults to 0

  • If specified thumbnails will be generated each secondsPerThumbnail seconds.

• framesPerThumbnail defaults to 0

  • If specified thumbnails will be generated each framesPerThumbnail frames.

• spritesheet defaults to false

  • Generate spritesheet or not.

• spriteSheetName defaults to "thumbnails"

  • Spritesheet file name

• spriteSheetOptions default to null

  • Spritesheet options passed to node-sprite .sprite() function.

TODO

• Use cool spritesheet generator
• Tests
• Use some kind of WebVTT generator?