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62 lines
1.4 KiB
62 lines
1.4 KiB
'use strict';
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/*!
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* Canvas - JPEGStream
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* Copyright (c) 2010 LearnBoost <tj@learnboost.com>
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* MIT Licensed
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*/
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/**
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* Module dependencies.
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*/
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var Stream = require('stream').Stream;
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/**
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* Initialize a `JPEGStream` with the given `canvas`.
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*
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* "data" events are emitted with `Buffer` chunks, once complete the
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* "end" event is emitted. The following example will stream to a file
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* named "./my.jpeg".
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*
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* var out = fs.createWriteStream(__dirname + '/my.jpeg')
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* , stream = canvas.createJPEGStream();
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*
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* stream.pipe(out);
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*
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* @param {Canvas} canvas
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* @param {Boolean} sync
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* @api public
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*/
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var JPEGStream = module.exports = function JPEGStream(canvas, options, sync) {
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var self = this
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, method = sync
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? 'streamJPEGSync'
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: 'streamJPEG';
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this.options = options;
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this.sync = sync;
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this.canvas = canvas;
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this.readable = true;
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// TODO: implement async
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if ('streamJPEG' == method) method = 'streamJPEGSync';
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process.nextTick(function(){
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canvas[method](options.bufsize, options.quality, options.progressive, function(err, chunk){
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if (err) {
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self.emit('error', err);
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self.readable = false;
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} else if (chunk) {
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self.emit('data', chunk);
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} else {
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self.emit('end');
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self.readable = false;
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}
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});
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});
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};
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/**
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* Inherit from `EventEmitter`.
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*/
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JPEGStream.prototype.__proto__ = Stream.prototype;
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