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Harukasan
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March 19, 2014
Technology
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2
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Node-canvas
Node-canvas
Sendagaya.js@pixiv
2014-03-19
5分で終わらなかった
Harukasan
PRO
March 19, 2014
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Transcript
Node-Canvas Sendagaya.js @ pixiv 2014-03-19
Harukasan a.k.a MICHII Shunsuke ಓҪढ़հ 2012 pixiv Inc. ΠϯϑϥνʔϜ Nginx
/ Apache / MySQL / MongoDB Kyototycoon / Solr / Traffic Server / Fluentd Kibana / Capistrano / Ruby on Rails / Macbook
None
Harukasan a.k.a MICHII Shunsuke ಓҪढ़հ 2014 10,000,000ਓϢʔβاը ɾInfrastructure ɾDeployment
Harukasan a.k.a MICHII Shunsuke ಓҪढ़հ 2014 10,000,000ਓϢʔβاը ɾInfrastructure ɾDeployment ɾServer
side Javascript (Drawer) ɾClient side JavaScript
Harukasan a.k.a MICHII Shunsuke ಓҪढ़հ 2014 10,000,000ਓϢʔβاը ɾ࠲ඪܥͷ૬ޓมΛܭࢉ ɾඳըܥσʔϞϯ
ʮେྔֆഅʯͷཪଆ (1) http://inside.pixiv.net/blog/2014/02/28/inside-of-massive-ema-collection-1/
Node-Canvas
Ý
Ý
Ý
Ý Ý αʔόଆͰੜ͠ͳͯ͘ྑ͍ ඳը͕ࠩى͖ͳ͍ τϥϑΟοΫ͕େ͖͍ ΫϥΠΞϯτෛՙ͕େ͖͍ αʔόଆͰੜ ඳըࠩͷՄೳੑ τϥϑΟοΫ͕খ͍͞ ΫϥΠΞϯτෛՙ͕খ͍͞
ΫϥΠΞϯτଆੜ αʔόʔଆੜ
Ý αʔόଆͰੜ ඳըࠩͷՄೳੑ τϥϑΟοΫ͕খ͍͞ ΫϥΠΞϯτෛՙ͕খ͍͞ αʔόʔଆੜ
Ý αʔόଆͰੜ! ඳըࠩͷՄೳੑ! τϥϑΟοΫ͕খ͍͞! ΫϥΠΞϯτෛՙ͕খ͍͞ αʔόʔଆੜ — CPUؤுΕ݁ߏͲ͏ʹͰͳΔ — ؾʹͳΒͳ͔ͬͨ
— ඳըͷτϥϑΟοΫͱ͔ΰϛ — ࣮؆୯ʹͳΔ
Node-Canvas
Node-Canvas ɾCanvas implementation for Node.JS ɾRenders with Cairo ɾOutput to
JPEG/PNG ɾalso supports PDF (no description)
Share Code in Client/Server Ý draw.coffee draw.coffee ← SAME CODE
→ node-canvas native canvas
Installation (OS X) $ brew install cairo $ export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/opt/X11/lib/pkgconfig
! $ npm install node-canvas
Create canvas Canvas = require('canvas') canvas = new Canvas(320, 240)
ctx = canvas.getContext('2d') CoffeeScript
Create canvas and draw Canvas = require('canvas') canvas = new
Canvas(320, 240) ctx = canvas.getContext('2d') ! ctx.save() ctx.fillStyle = '#ff0000' ctx.fillRect(100, 100, 200, 200) ctx.restore()
Create canvas and draw ɾ ϝιουϒϥβͱಉ͡ ɾ ඳըࣗମϒϥβͱ΄΅ಉ͡ ɾ ͑ΔίϯςΩετ2DίϯςΩετ͚ͩ
Load Image {Image} = Canvas = require 'canvas' fs =
require 'fs' path = 'test.png' fs.readFile path, (err, data) -> return next(null) if err or not data img = new Image img.src = data ctx.drawImage img, 0, 0, img.width, img.height
Load Image ɾ ctx.drawImageͰඳըͰ͖Δ ɾ ΫϥΠΞϯτͱಉ͡Α͏ʹImageΦϒδΣ ΫτΛ͑Δʂʂʂ
Output to PNG with Stream path = ‘test.png' out =
fs.createWriteStream path out.on 'finish', -> console.log 'fs: finish' ! canvas.createPNGStream().pipe out
Output to JPEG with Stream path = 'test.png' out =
fs.createWriteStream path out.on 'finish', -> console.log 'fs: finish' ! canvas.createJPEGStream(quality: 75).pipe out
Output to Image ɾ ετϦʔϜग़ྗͰ͖Δ ɾ ग़ྗܗࣜJPEG/PNG ɾ DataεΩʔϜURLʹग़ྗͰ͖Δ
Render Image Quality ctx.patternQuality = fast good best nearest bilinear
Render Image Quality ctx.patternQuality = fast # => nearest good
# => biliiner best # => biliinear nearest bilinear
Resize Quality ɾ όΠϦχΞ͔͑͠ͳ͍ ɾ ߴը࣭ʹ͢ΔʹImageMagickΛ͏ ɾ imagemagick-native͍͚Ͳ ϒϩοΩϯάϝιου͔͠ͳ͍
·ͱΊ ɾ JSΛ͏ͱΫϥΠΞϯτͱαʔόαΠυͰ ίʔυΛڞ༗Ͱ͖ͯ͘͢͝خ͍͠ ɾ Node-Canvas݁ߏී௨ʹಈ͘