image-to-slices

Node.js module for converting image into slices with the given reference lines. Backed by Slices and image-clipper.

Usage no npm install needed!

<script type="module">
  import imageToSlices from 'https://cdn.skypack.dev/image-to-slices';
</script>

README

image-to-slices

image-to-slices

Node.js module for converting image into slices with the given reference lines. Backed by Slices and image-clipper.

NPM version Downloads Bower version Build Status

image-to-slices

Installation

Node.js

npm install image-to-slices

Since the server-side Node.js doesn't natively support Canvas, you'll need previously install Cairo which is depended by node-canvas, see node-canvas#Installation for detail.

npm install canvas

Bower

bower install image-to-slices

Quick Start

var imageToSlices = require('image-to-slices');

var lineXArray = [100, 200];
var lineYArray = [100, 200];
var source = '/path/to/image.jpg'; // width: 300, height: 300

imageToSlices(source, lineXArray, lineYArray, {
    saveToDir: '/path/to/'
}, function() {
    console.log('the source image has been sliced into 9 sections!');
});

Client-side (browser)

Simply download the latest minified version from the dist/ folder. All APIs are available in a global object called imageToSlices.

<script src="./dist/image-to-slices.js"></script>
var imageToSlices = window.imageToSlices;
imageToSlices(source, lineXArray, lineYArray, {
    saveToDataUrl: true
}, function(dataUrlList) {
    console.log('sliced', dataUrlList);
});

You can also use image-to-slices via AMD or CMD.

Command Line Interface

Usage: image-to-slices [options]

Options:

-h, --help                            output usage information
-v, --version                         output the version number
-s, --source <source file>            the path where the source image file
-x --lineX <x1,x2,...>                reference lines of the X axis
-y --lineY <y1,y2,...>                reference lines of the Y axis
-m --middleBoundaryMode <true|false>  enable middle boundary mode. Default is false
-o --output <output directory>        the directory where the image slices will be saved. Default is the current working directory of the process

Below is an example:

$ image-to-slices -s ./example/images/building.png -x 20,100 -y 100 -o ./example/

Note that the Cli usage require node-canvas.

Example

Online example: http://leonshi.com/image-to-slices/

API

var imageToSlices = require('image-to-slices');

imageToSlices(source, lineXArray, lineYArray [, options], callback)

  • source: the path where the source image. Keep in mind that origin policies apply to the image source, and you may not use cross-domain images without CORS.
  • lineXArray: reference lines of the X axis
  • lineYArray: reference lines of the Y axis
  • options: slice with some optional parameters, see options for detail.
  • callback: a function to be executed when slicing is complete.

imageToSlices.configure(options)

Configure properties for global, properties changed by the imageToSlices.configure method will take effect for every instance created after the change.

var imageToSlices = require('image-to-slices');
imageToSlices.configure({
    clipperOptions: {
        canvas: require('canvas')
    }
});

See Options for available properties.

Options

saveToDir

The directory path where the image slices will be saved.

Note that the path must be really exists.

middleBoundaryMode

Either true or false, default is false.

If set to true, this will put spaces between each two X axis as parent-block, the areas between the first Y axis and last Y axis will be children of the parent-block, and it will generate boundary data.

See Slices#middleBoundaryMode for detail.

clipperOptions

Configuration properties for the image-clipper.

See image-clipper#configure-options for available properties.

saveToDataUrl

You should use either saveToDir: true or saveToDataUrl: true, default is false.

If set to true, then it will doesn't save the image slices as file but rather return data URI of the slices, and callback will be passed the result data URI.

Below is an example:

ImageToSlices('path/to/image.jpg', [100], [100], {
  saveToDataUrl: true
}, function(dataUrlList) {
  console.log('sliced!', dataUrlList);
});

The dataUrlList returned will be like below:

[
    { width: 100, height: 100, x: 0, y: 0, dataURI: 'data:image/jpeg;base64,....' },
    { width: 400, height: 100, x: 100, y: 0, dataURI: 'data:image/jpeg;base64,....' },
    { width: 100, height: 400, x: 0, y: 100, dataURI: 'data:image/jpeg;base64,....' },
    { width: 400, height: 400, x: 100, y: 100, dataURI: 'data:image/jpeg;base64,....' }
]

Below is another example which middleBoundaryMode is set to true:

ImageToSlices('path/to/image.jpg', [100, 300], [100, 200, 300], {
  saveToDataUrl: true,
  middleBoundaryMode: true
}, function(dataUrlList) {
  console.log('sliced!', dataUrlList);
});

And the dataUrlList returned will be like below:

[
    {
        "width": 500,
        "height": 100,
        "x": 0,
        "y": 0,
        dataURI: 'data:image/jpeg;base64,....',
        "children": [
            {
                "width": 100,
                "height": 100,
                "x": 100,
                "y": 0,
                "left": 0,
                "top": 0,
                "parentBlockIndex": 0,
                "index": 0,
                dataURI: 'data:image/jpeg;base64,....',
            },
            {
                "width": 100,
                "height": 100,
                "x": 200,
                "y": 0,
                "left": 100,
                "top": 0,
                "parentBlockIndex": 0,
                "index": 1,
                dataURI: 'data:image/jpeg;base64,....',
            }
        ],
        "boundary": {
            "leftTop": {
                "x": 100,
                "y": 0
            },
            "rightBottom": {
                "x": 300,
                "y": 100
            }
        }
    },
    ...
]

Where is this library used?

If you are using this library in one of your projects, add it in this list :)

Testing

npm test

License

MIT, see the LICENSE file for detail.