gb-image-decoder

GameBoy-Tile format Image Decoders

This package renders GameBoy-encoded images.

You may use the gbp-decode package to decode various sources.
Or you may want to use the arduino-gameboy-printer-emulator.
There are a lot more similar projects for aquiring raw tile data.

Usage

Browser

Monochrome images

import { getMonochromeImageUrl, ExportFrameMode, Rotation } from 'gb-image-decoder';

const tiles: string[] = [ // need 360 of these for a 160x144 image
  '7D FF 0A FF 7D FF FF FF 5F FF BB FF 5D FF FF FF', '75 FF A2 FF 44 FF FF FF 5D FF FF FF FF FF FF FF', '55 FF 1F FF 57 FF FF FF 7D FF FF FF FF FF FF FF', '77 FF FD FF 57 FF FF FF 75 FF FF FF DF FF FF FF',
];
const monoPalette = ['#ffffff', '#aaaaaa', '#555555', '#000000'];

const imageSrc = await getMonochromeImageUrl({
  imagePalette: monoPalette,
  tiles,
  
  // Optional parameters (with it's defaults):
  // framePalette: monoPalette,
  // imageStartLine: 2,
  // tilesPerLine: 20,
  // scaleFactor: 1,
  // rotation: Rotation.DEG_0,
  // handleExportFrame: ExportFrameMode.FRAMEMODE_KEEP,
})

RGB(N) images

getRGBNImageUrl provides a convenience function to combine separate monochrome tile sets into one colored image.
the RGBNTiles type contains the four possible channels (r, g, b, n)
The optional neutral layer will be overlayed on the previously combined rgb image.

import { getRGBNImageUrl, ExportFrameMode, RGBNTiles, RGBNPalette, defaultRGBNPalette } from 'gb-image-decoder';

const tiles: RGBNTiles = {
  r: ['7D FF 0A FF 7D FF FF FF 5F FF BB FF 5D FF FF FF', '75 FF A2 FF 44 FF FF FF 5D FF FF FF FF FF FF FF', '55 FF 1F FF 57 FF FF FF 7D FF FF FF FF FF FF FF', '77 FF FD FF 57 FF FF FF 75 FF FF FF DF FF FF FF'],
  g: ['7F FF BF FF FF FF FF FF DF FF FF FF FF FF FF FF', 'A2 D5 FC C3 4C D3 FE C1 D8 E4 ED F2 FF F1 DB FC', 'EA 55 83 FC 48 F5 07 F8 A4 53 A8 07 A3 5C FE 01', 'FF 3F FF 3F FF 3F 7F BF FF 3F FF 7F 7D FF FF FF'],
  b: ['F7 FF A3 FF FF FF FF FF FF FF FF FF FF FF FF FF', '0A F5 80 FF 40 FF F1 FE FB FD F0 FF 52 FD E1 FE', '88 77 40 BF 2A D5 18 EF 88 77 04 FB AA 55 17 E8', 'A0 5F 51 AE AA 55 54 AB AA 55 05 FA AA 55 67 98'],
  // neutral image is optional
};

const imageSrc = await getRGBNImageUrl({
  palette: defaultRGBNPalette,
  tiles,
  
  // Optional parameters (with it's defaults):
  // imageStartLine: 2,
  // tilesPerLine: 20,
  // scaleFactor: 1,
  // rotation: Rotation.DEG_0,
  // handleExportFrame: ExportFrameMode.FRAMEMODE_KEEP,
})

Nodejs

Within a node environment, getMonochromeImageUrl and getRGBNImageUrl cannot be called, as they rely on the use of URL.createObjectURL(blob).

Instead the internally used functions need to be called. All parameters are mandatory. The resulting data and dimensions can be used to create an image e.g. by using the canvas package

Monochrome images

import { getRawMonochromeImageData, FullMonochromeImageCreationParams, ExportFrameMode } from 'gb-image-decoder';

const monoPalette = ['#ffffff', '#aaaaaa', '#555555', '#000000'];

const fullParams: FullMonochromeImageCreationParams = {
  framePalette: monoPalette,
  imagePalette: monoPalette,
  tiles, // as in browser example
  imageStartLine: 2,
  tilesPerLine: 20,
  scaleFactor: 1,
  rotation: Rotation.DEG_0,
  handleExportFrame: ExportFrameMode.FRAMEMODE_KEEP,
};

const { data, dimensions } = getRawMonochromeImageData(fullParams);

RGB(N) images

import { getRawRGBNImageData, FullRGBNImageCreationParams, defaultRGBNPalette, ExportFrameMode } from 'gb-image-decoder';

const monoPalette = ['#ffffff', '#aaaaaa', '#555555', '#000000'];

const fullParams: FullRGBNImageCreationParams = {
  palette: defaultRGBNPalette,
  tiles, // as in browser example
  imageStartLine: 2,
  tilesPerLine: 20,
  scaleFactor: 1,
  rotation: Rotation.DEG_0,
  handleExportFrame: ExportFrameMode.FRAMEMODE_KEEP,
};

const { data, dimensions } = getRawRGBNImageData(fullParams);

License: MIT

LICENSE