ARToolKit.js

Emscripten port of ARToolKit to JavaScript.

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NOTE:

When writing JavaScript and making changes be aware that the emscripten uglifier does not support the ES6 syntax.

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Project Structure

• build/ (compiled debug and minified versions of ARToolKit.js)
• doc/ (documentation, coming...)
• emscripten/ (source code for ARToolKit.js)
• examples/ (demos and examples using ARToolKit.js)
• js/ (compiled versions of ARToolKit.js with Three.js helper api)
• tools/ (build scripts for building ARToolKit.js)

WebAssembly

JSARToolKit5 supports WebAssembly. The libary builds two WebAssembly artefacts during the build process. These are build/artoolkit_wasm.js and build/artoolkit_wasm.wasm. To use those include the artoolkit_wasm.js into your html page and define var artoolkit_wasm_url = '<<PATH TO>>/artoolkit_wasm.wasm'; prior to loading the artoolkit_wasm.js file, like so:

<script type='text/javascript'>
      var artoolkit_wasm_url = '../build/artoolkit_wasm.wasm';
</script>
<script src="../build/artoolkit_wasm.js"></script>

As loading the WebAssembly artefact is done asynchronous there is a callback that is called once everything is ready.

window.addEventListener('artoolkit-loaded', () => {  
    //do artoolkit stuff here
});

See examples/simple_image_wasm.html for details.

Clone the repository

1. Clone this repository
2. Clone ARToolKit5 project to get the latest source files. From within jsartoolkit5 directory do git submodule update --init. If you already cloned ARToolKit5 to a different directory you can:

• create a link in the jsartoolkit5/emscripten/ directory that points to ARToolKit5 (jsartoolkit5/emscripten/artoolkit5) (Linux and macOS only)
• or, set the ARTOOLKIT5_ROOT environment variable to point to your ARToolKit5 clone
• or, change the tools/makem.js file to point to your artoolkit5 clone (line 62, 83, 107, 140)

Build Instructions

Build using Docker

1. Install Docker (if you havn't already) Docker -> Get Docker
2. From inside jsartoolkit5 directory run docker run -dit --name emscripten -v $(pwd):/src trzeci/emscripten-slim:sdk-tag-1.37.34-64bit bash
3. docker exec emscripten npm run build

Build with manual emscripten setup

1. Install build tools

2. Install node.js (https://nodejs.org/en/)

3. Install python2 (https://www.python.org/downloads/)

4. Install emscripten (http://kripken.github.io/emscripten-site/docs/getting_started/downloads.html#download-and-install)

5. Clone ARToolKit5 project to get the latest source files. From within jsartoolkit5 directory do git submodule update --init. If you already cloned ARToolKit5 to a different directory you can:

• create a link in the jsartoolkit5/emscripten/ directory that points to ARToolKit5 (jsartoolkit5/emscripten/artoolkit5)
• or, set the ARTOOLKIT5_ROOT environment variable to point to your ARToolKit5 clone
• or, change the tools/makem.js file to point to your artoolkit5 clone (line 62, 83, 107, 140)

3. Building
4. Make sure EMSCRIPTEN env variable is set (e.g. EMSCRIPTEN=/usr/lib/emsdk_portable/emscripten/master/)
5. Run npm run build

During development, you can run npm run watch, it will rebuild the library everytime you change ./js/ directory.

4. The built ASM.js files are in /build. There's a build with debug symbols in artoolkit.debug.js and the optimized build with bundled JS API in artoolkit.min.js.

ARToolKit JS API

<script async src="build/artoolkit.min.js">
// include optimized ASM.js build and JS API
</script>

ARToolKit JS debug build

<script src="build/artoolkit.debug.js">
// - include debug build
</script>
<script src="js/artoolkit.api.js">
// - include JS API
</script>

ARToolKit Three.js helper API

<script async src="build/artoolkit.min.js">
// - include optimized ASM.js build and JS API
</script>
<script async src="three.min.js">
// - include Three.js
</script>
<script async src="js/artoolkit.three.js">
// - include Three.js helper API
</script>
<script>
window.ARThreeOnLoad = function () {
console.log("Three.js helper API loaded");
};
if (window.ARController && window.ARController.getUserMediaThreeScene) {
ARThreeOnLoad();
}
</script>

Examples

See examples/ for examples on using the raw API and the Three.js helper API.

The basic operation goes like this:

1. Load a ARCameraParam object
2. Create a ARController object
3. Set pattern detection mode
4. Load pattern markers or multimarkers if needed
5. Add a 'getMarker' event listener
6. Call ARController.process(img)

<script src="build/artoolkit.min.js"></script>
<script>
  var param = new ARCameraParam();

  param.onload = function () {
    var img = document.getElementById('my-image');
    var ar = new ARController(img.width, img.height, param);

    // Set pattern detection mode to detect both pattern markers and barcode markers.
    // This is more error-prone than detecting only pattern markers (default) or only barcode markers.
    //
    // For barcode markers, use artoolkit.AR_MATRIX_CODE_DETECTION
    // For pattern markers, use artoolkit.AR_TEMPLATE_MATCHING_COLOR
    //
    ar.setPatternDetectionMode(artoolkit.AR_TEMPLATE_MATCHING_COLOR_AND_MATRIX);
    
    ar.addEventListener('markerNum', function (ev) {
      console.log('got markers', markerNum);
    });
    ar.addEventListener('getMarker', function (ev) {
      console.log('found marker?', ev);
    });
    ar.loadMarker('Data/patt.hiro', function (marker) {
      console.log('loaded marker', marker);
      ar.process(img);
    });
};

  param.src = 'Data/camera_para.dat';
</script>

Public

the calls your JS apps needs

• artoolkit.init(path, camera_param_path) - load path for artoolkit emscripten files
• artoolkit.onReady(callback) - runs callback when artoolkit has completely downloaded, initalized and ready to run
• artoolkit.setup(width, height); - initalize a buffer size for a canvas of width & height
• artoolkit.process(canvas); - extracts a frame from a canvas and process it
• artoolkit.debugSetup() - enables debugging, adds a threshold image to the dom
• artoolkit.getDetectedMarkers() - returns an array of detected markers from last detection process
• artoolkit.getCameraMatrix() - returns the projection matrix computed from camera parameters
• artoolkit.getTransformationMatrix() - returns the 16-element WebGL transformation matrix

Internals

calls called from emscripten runtime -> artoolkit.js

• artoolkit.onFrameMalloc(object) - gets called when frame buffer gets allocated for canvas
• artoolkit.onMarkerNum(number) - gets called with the numbers of markers detected
• artoolkit.onGetMarker(object, index) - gets called with the marker struct for the positioned marker

calls available from js -> emscripten

• _setup(width, height)
• _setThreshold(int) - 0 to 255
• _process()
• _setDebugMode(boolean)
• _addMarker(string)
• setThreshold
• setThresholdMode() eg. `Module.setThresholdMode(Module.AR_LABELING_THRESH_MODE_AUTO_MEDIAN / AR_LABELING_THRESH_MODE_AUTO_OTSU );
• setLabelingMode
• setPatternDetectionMode
• setMatrixCodeType() : Eg. Module.setMatrixCodeType(Module.AR_MATRIX_CODE_3x3);
• setImageProcMode
• setPattRatio

Examples

artoolkit.init('', 'camera_para.dat').onReady(function() {
artoolkit.setProjectionNearPlane(1);
artoolkit.setProjectionFarPlane(1000);
artoolkit.setPatternDetectionMode(artoolkit.CONSTANTS.AR_MATRIX_CODE_DETECTION);
artoolkit.setMatrixCodeType(artoolkit.CONSTANTS.AR_MATRIX_CODE_4x4);
})

artoolkit.init('', 'camera_para.dat').onReady(function() {
artoolkit.addMarker('../bin/Data/patt.hiro', function(marker) {
artoolkit.process(v);
})
})

Constants

prepend all these constants with Module. or artoolkit.CONSTANTS to access them

- AR_DEBUG_DISABLE
- AR_DEBUG_ENABLE
- AR_DEFAULT_DEBUG_MODE
- AR_LABELING_WHITE_REGION
- AR_LABELING_BLACK_REGION
- AR_DEFAULT_LABELING_MODE
- AR_DEFAULT_LABELING_THRESH
- AR_IMAGE_PROC_FRAME_IMAGE
- AR_IMAGE_PROC_FIELD_IMAGE
- AR_DEFAULT_IMAGE_PROC_MODE
- AR_TEMPLATE_MATCHING_COLOR
- AR_TEMPLATE_MATCHING_MONO
- AR_MATRIX_CODE_DETECTION
- AR_TEMPLATE_MATCHING_COLOR_AND_MATRIX
- AR_TEMPLATE_MATCHING_MONO_AND_MATRIX
- AR_DEFAULT_PATTERN_DETECTION_MODE
- AR_USE_TRACKING_HISTORY
- AR_NOUSE_TRACKING_HISTORY
- AR_USE_TRACKING_HISTORY_V2
- AR_DEFAULT_MARKER_EXTRACTION_MODE
- AR_MAX_LOOP_COUNT
- AR_LOOP_BREAK_THRESH
- AR_MATRIX_CODE_3x3
- AR_MATRIX_CODE_3x3_HAMMING63 5
- AR_MATRIX_CODE_3x3_PARITY65 2
- AR_MATRIX_CODE_4x4
- AR_MATRIX_CODE_4x4_BCH_13_9_3 7
- AR_MATRIX_CODE_4x4_BCH_13_5_5 10
- AR_LABELING_THRESH_MODE_MANUAL
- AR_LABELING_THRESH_MODE_AUTO_MEDIAN
- AR_LABELING_THRESH_MODE_AUTO_OTSU
- AR_LABELING_THRESH_MODE_AUTO_ADAPTIVE
- AR_MARKER_INFO_CUTOFF_PHASE_NONE
- AR_MARKER_INFO_CUTOFF_PHASE_PATTERN_EXTRACTION
- AR_MARKER_INFO_CUTOFF_PHASE_MATCH_GENERIC
- AR_MARKER_INFO_CUTOFF_PHASE_MATCH_CONTRAST
- AR_MARKER_INFO_CUTOFF_PHASE_MATCH_BARCODE_NOT_FOUND
- AR_MARKER_INFO_CUTOFF_PHASE_MATCH_BARCODE_EDC_FAIL
- AR_MARKER_INFO_CUTOFF_PHASE_MATCH_CONFIDENCE
- AR_MARKER_INFO_CUTOFF_PHASE_POSE_ERROR
- AR_MARKER_INFO_CUTOFF_PHASE_POSE_ERROR_MULTI
- AR_MARKER_INFO_CUTOFF_PHASE_HEURISTIC_TROUBLESOME_MATRIX_CODES