gif-frames

1.0.1 • Public • Published

gif-frames

A pure JavaScript tool for extracting GIF frames and saving to file. Works in Node or the browser. Uses get-pixels and save-pixels under the hood.

NPM

Install

npm install gif-frames

CDN scripts

If you're not using npm, you can include one of these in your HTML file:

<!-- unminified -->
<script src="https://unpkg.com/gif-frames@0.4.0?main=bundled"></script>
 
<!-- minified -->
<script src="https://unpkg.com/gif-frames@0.4.0?main=bundled-min"></script>

This will expose gifFrames as a global variable.

require('gif-frames')(options[, callback])

var gifFrames = require('gif-frames');
var fs = require('fs');
 
gifFrames({ url: 'image.gif', frames: 0 }).then(function (frameData) {
  frameData[0].getImage().pipe(fs.createWriteStream('firstframe.jpg'));
});

Options:

  • url (required): The pathname to the file, or an in-memory Buffer
  • frames (required): The set of frames to extract. Can be one of:
  • outputType (optional, default 'jpg'): Type to use for output (see type for save-pixels)
  • quality (optional): Jpeg quality (see quality for save-pixels)
  • cumulative (optional, default false): Many animated GIFs will only contain partial image information in each frame after the first. Specifying cumulative as true will compute each frame by layering it on top of previous frames. Note: the cost of this computation is proportional to the size of the last requested frame index.

The callback accepts the arguments (error, frameData).

Returns:

A Promise resolving to the frameData array (if promises are supported in the running environment)

frameData

An array of objects of the form:

{
  getImage,
  frameIndex,
  frameInfo
}

getImage()

Returns one of:

  • A drawn canvas DOM element, if options.outputType is 'canvas'
  • A data stream which can be piped to file output, otherwise

frameIndex

The index corresponding to the frame's position in the original GIF (not necessarily the same as the frame's position in the result array)

frameInfo

It is an Object with metadata of the frame. Fields:

Name Type Description
x Integer Image Left Position
y Integer Image Top Position
width Integer Image Width
height Integer Image Height
has_local_palette Boolean Image local palette presentation flag
palette_offset Integer Image palette offset
palette_size Integer Image palette size
data_offset Integer Image data offset
data_length Integer Image data length
transparent_index Integer Transparent Color Index
interlaced Boolean Interlace Flag
delay Integer Delay Time (1/100ths of a second)
disposal Integer Disposal method

See GIF spec for details

Examples

Writing selected frames to the file system in Node:

var gifFrames = require('gif-frames');
var fs = require('fs');
 
gifFrames(
  { url: 'image.gif', frames: '0-2,7', outputType: 'png', cumulative: true },
  function (err, frameData) {
    if (err) {
      throw err;
    }
    frameData.forEach(function (frame) {
      frame.getImage().pipe(fs.createWriteStream(
        'image-' + frame.frameIndex + '.png'
      ));
    });
  }
);

Drawing first frame to canvas in browser (and using a Promise):

var gifFrames = require('gif-frames');
 
gifFrames({ url: 'image.gif', frames: 0, outputType: 'canvas' })
  .then(function (frameData) {
    document.body.appendChild(frameData[0].getImage());
  }).catch(console.error.bind(console));

Package Sidebar

Install

npm i gif-frames

Weekly Downloads

9,120

Version

1.0.1

License

MIT

Unpacked Size

1.18 MB

Total Files

7

Last publish

Collaborators

  • benwiley4000