thumbsupply

Asynchronous Node.js module to create, cache and fetch thumbnails from
videos. It uses ffmpeg to generate thumbnails and ES6 Promise.

The API is more reliable now and is unlikely to have major changes before stable release.

Healthy criticisms, feature requests and issues are welcome.

NOTE: Since v0.2, the module no longer maintains thumbnails separately
for each application. This behavior is intended to improve the performance
and utilize caching as far as possible.

Installation

``bash
npm install thumbsupply
`

Usage

$3

The resolved promise gives filepath of the generated thumbnail. In case
of modifications to be performed on the generated thumbnail, it's
recommended to work on a copy.

Using generateThumbnail() method by default enables caching to speeden
up the process.

`javascript
const thumbsupply = require('thumbsupply');

thumbsupply.generateThumbnail('some-video.mp4')
.then(thumb => {
// serve thumbnail
})
`

It accepts options to control timestamp and size of the thumbnail. The
forceCreate option can be used to generate the thumbnail every
time. Mimetype of the file can be specified using mimetype
option. It overrides mimetype derived from the file extension and
can be used for cases where such derivation is not possible. cacheDir
allows configuring the directory to store the thumbnail cache. Unless
there is an explicit need, it is good to use shared cache.

`javascript
const thumbsupply = require('thumbsupply');

thumbsupply.generateThumbnail('some-video.mp4', {
size: thumbsupply.ThumbSize.MEDIUM, // or ThumbSize.LARGE
timestamp: "10%", // or 30 for 30 seconds
forceCreate: true,
cacheDir: "~/myapp/cache",
mimetype: "video/mp4"
})
`

NOTE: Thumbnails which are older than the video get expired
automatically.

$3

Instead of creating a thumbnail, sometimes you may need to get the
thumbnail if it exists.

`javascript
const thumbsupply = require('thumbsupply');

thumbsupply.lookupThumbnail('some-video.mp4')
.then(thumb => {
// serve thumbnail
})
.catch(err => {
// thumbnail doesn't exist
});
``

Features on the way

_thumbsupply_ will soon be supporting music, pictures and so on. The
architecture required is already shipped.

Developers can experiment with some of the non public API's to create
thumbnail suppliers supporting new formats. Documentation on how to do
that will be released with the production version.

External bugs

+ _ffmpeg_ is producing screenshots which mismatch the resolution
specified by 1 unit.