autotrace

autotrace
========

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

More details about AutoTrace can be found [here][1].

Requirements
--------

* [AutoTrace][1]

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;

``sh
autotrace --help
`

Basic Usage
--------
Convert a PNG to SVG.

`javascript
// 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
--------
`javascript
// 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.

[1]: http://autotrace.sourceforge.net/