ase-parser

Parse Aseprite files with Node.js, no external dependencies.

Install

To install for use:

npm i ase-parse

Instructions

You'll probably want to get the Buffer of the Aseprite file in whatever way you feel like. For the example, we'll just use fs.readFileSync(). But you can get it from a network request, etc.

const Aseprite = require('ase-parser');
const fs = require('fs');

const buff = fs.readFileSync('./somefile.aseprite');
const aseFile = new Aseprite(buff, 'somefile.aseprite');

aseFile.parse();
console.log(aseFile.numFrames);

After parsing, you can get the data and do something like generate an image with the sharp npm lib, which accepts raw pixel data and supports image composition.

Here is a more advanced example generating a png image of the first frame using the sharp lib.

const Aseprite = require('ase-parser');
const fs = require('fs');
const sharp = require('sharp');

async function makePNG() {
  const buff = fs.readFileSync('./my_chocobo.aseprite');
  const ase = new Aseprite(buff, 'my_chocobo.aseprite');
  
  ase.parse();
  // Create a blank png image buffer that's the same size as the Aseprite sprite (only make the promise because we'll use Promise.all a little later)
  const bgPromise = sharp({create: {
    width: ase.width,
    height: ase.height,
    channels: 4,
    background: {r: 0, g: 0, b: 0, alpha: 0}
  }}).png().toBuffer();
  
  // Get the cels for the first frame
  const cels = ase.frames[0].cels;
  
  // Create png image buffers per cel to create an image of the first frame (creating the Promises to be used)
  const otherPromises = cels.map(cel => {
    return sharp(cel.rawCelData, {raw: {width: cel.w, height: cel.h, channels: 4}}).png().toBuffer();
  });
  
  // Run the promises all at once to get the buffers for the base image and the cels to combine
  const [ bg, ...others ] = await Promise.all([bgPromise, ...otherPromises]).catch(console.log);
  
  // take the first image and add on the png buffers on top of it (the cels should be in order from bottom to top from the parse)
  const finalBuff = await sharp(bg)
    .composite(others.map((img, index) => ({
      input: img,
      top: cels[index].ypos,
      left: cels[index].xpos
    })))
    .png()
    .toBuffer();
  // saves the file as a png with the buffer from sharp.composite
  fs.writeFileSync(ase.name.replace('.aseprite', '.png'), finalBuff);
}

makePNG();

Aseprite Functions

constructor

Parameters:

• buffer: Expects a Node.js Buffer of the Aseprite file.
• name: Expects a string that's the name of the Aseprite file, including the extension.

Returns:

• Aseprite: Returns Aseprite.

Example:

const Aseprite = require('ase-parser');
const fs = require('fs');

const buff = fs.readFileSync('./somefile.aseprite');
const aseFile = new Aseprite(buff, 'somefile.aseprite');

parse

Description:
Parses the Aseprite file and populates the Aseprite class with the information from the file.

Parameters:

• none

Returns:

• none

Example:

const Aseprite = require('ase-parser');
const fs = require('fs');

const buff = fs.readFileSync('./somefile.aseprite');
const aseFile = new Aseprite(buff, 'somefile.aseprite');

aseFile.parse();

Aseprite Object

| Field | Type | Description | |--------------|------------------------|----------------------------------------| | frames | array of frame objects | frames | | layers | array of layer objects | layers | | fileSize | integer | size of the file (in bytes) | | numFrames | integer | number of frames the Aseprite file has | | width | integer | width (in pixels) | | height | integer | height (in pixels) | | colorDepth | integer | color depth (in bits per pixel) | | paletteIndex | integer | position of the indexed color based on the palette | | numColors | integer | number of colors | | pixelRatio | string | width:height | | name | string | name of the file | | tags | arry of tag objects | tags | | colorProfile | colorProfile object | Color profile | | palette | palette object | Palette |

Frame Object

| Field | Type | Description | |---------------|-----------------------|------------------| | bytesInFrame | integer | size (in bytes) | | frameDuration | integer | duration (in ms) | | cels | array of cel objects | cels |

Layer Object

| Field | Type | Description | |-----------------|---------|---------------------| | flags | integer | flags for the layer | | type | integer | type | | layerChildLevel | integer | layer child level | | opacity | integer | opacity (0-255) | | name | string | name of layer |

Tag Object

| Field | Type | Description | |---------------|---------|----------------------------------------| | from | integer | first frame index | | to | integer | last frame index | | animDirection | string | Forward, Reverse or Ping-pong | | color | string | hex color of the tag (no # included) | | name | string | name |

Color Profile Object

| Field | Type | Description | |--------|---------|-------------------------| | type | string | None, sRGB or ICC | | flag | integer | fixed gamma flag | | fGamma | integer | fixed gamma | | icc? | buffer | ICC profile data |

Palette Object

| Field | Type | Description | |-------------|------------------------|--------------------------| | paletteSize | integer | number of colors | | firstColor | integer | index of the first color | | lastColor | integer | index of the last color | | colors | array of color objects | colors | | index? | integer | position of the indexed color based on the palette |

Cel Object

| Field | Type | Description | |------------|---------|----------------------------------------------| | layerIndex | integer | index of the layer associated | | xpos | integer | x position of the cel compared to the sprite | | ypos | integer | y position of the cel compared to the sprite | | opacity | integer | opacity (0-255) | | celType | integer | internally used | | w | integer | width (in pixels) | | h | integer | height (in pixels) | | rawCelData | Buffer | raw cel pixel data |

Color Object

| Field | Type | Description | |-------|---------|-----------------------------------------------| | red | integer | red value (0-255) | | green | integer | green value (0-255) | | blue | integer | blue value (0-255) | | alpha | integer | alpha value (0-255) | | name | string | 'none' or the actual color name if it has one |

Further Info

If you would like to read up on the Aseprite file spec: Spec