autotrace

A simple interface for converting raster images into vector graphics using AutoTrace.

More details about AutoTrace can be found here.

Requirements

• AutoTrace

Installation

$ npm install -g autotrace

Output Formats

Typical output formats include EPS, AI, SVG, DXF, PDF, MIF and Cairo. All supported output formats can be found by running;

autotrace --help

Basic Usage

Convert a PNG to SVG.

// input file, options and a callback
autotrace('/path/to/image.png', {
	outputFile: '/tmp/out.svg'
}, function(err, buffer) {
	if (!err) console.log('done');
});

// options and a callback
autotrace({
	inputFile: '/path/to/image.png'
	, outputFile: '/tmp/out.eps'
}, function(err, buffer) {
	if (!err) console.log('done');
});

// chaining
autotrace()
	.inputFile('/path/to/image.png')
	.outputFile('/tmp/out.pdf')
	.exec(function(err, buffer) {
		if (!err) console.log('done');
	});

Streams

// stream output to a WriteableStream
autotrace('/path/to/image.png')
	.outputFormat('svg')
	.stream(function(err, stdout, stderr) {
		var writeStream = fs.createWriteStream('/tmp/out.svg');
  		stdout.pipe(writeStream);
	});
	
// without a callback, .stream() returns a stream
// this is just a convenience wrapper for above.
var writeStream = fs.createWriteStream('/tmp/out.pdf');
autotrace('/path/to/image.png', {outputFormat: 'pdf'})
	.stream()
	.pipe(writeStream);

API

autotrace(inputFile, options, callback)

The first argument can be either a file path or an options object. The only required option is inputFile (when not passing as the first argument); all others are optional. Refer to the above usage section for examples.

Options/Methods - all of AutoTrace's are supported along with some custom ones.

AutoTrace

# Refer to AutoTrace's help for details.
man autotrace

• backgroundColor
• centerline
• colorCount
• cornerAlwaysThreshold
• cornerSurround
• cornerThreshold
• despeckleLevel
• despeckleTightness
• dpi
• errorThreshold
• filterIterations
• inputFormat
• lineReversionThreshold
• lineThreshold
• log
• outputFile
• outputFormat
• preserveWidth
• removeAdjacentCorners
• tangentSurround
• reportProgress
• debugArch
• debugBitmap
• version
• widthWeightFactor

Custom

• inputFile - path to the input file.
• customBin - set a custom path to the AutoTrace binary.
• binArgs - returns an array of the args to be passed to AutoTrace.
• debugExec - returns the full exec + args as a string. Useful for debugging.

Methods

• exec(callback) - start the tracing process. returns (err, buffer).
• stream - stream the results of the tracing. returns (err, stdout, stderr).

If a callback (e.g. autotrace(file, callback)) is provided the exec method is automatically called for you.