Improving performance with responsive (and responsible!) images [OpenWest]

OpenWest,
2015-05-07
https://github.com/nwtn/pres-respimg-perf-openwest

Transcript

1. David Newton, St. Michael’s Hospital 1 Improving performance with responsive (and responsible!) images OpenWest, 2015-05-07 Twitter: @newtron Github: @nwtn Email: david@davidnewton.ca Slides: https://github.com/nwtn/pres-respimg-perf-openwest
2. 2 Web performance
3. “ 3 Many of us are fortunate to live in high bandwidth regions, but there are still large portions of the world that do not. By keeping your client side code small and lightweight, you can literally open your product up to new markets. —Chris Zacharias, Page Weight Matters (emphasis mine)
4. “ 4 Good performance is good design. —Brad Frost
5. 5 Why images?
6. 6 —Marc Andreessen, www-talk, February 1993
8. “ 8 More human beings today have access to a cellphone than…a clean toilet. –Anand Giridharadas, New York Times April 10 2010
9. “ 8 More human beings today have access to a cellphone than…a clean toilet. –Anand Giridharadas, New York Times April 10 2010
10. 9 — OpenSignal, Android Fragmentation Visualized (August 2014)
11. 10 —https://twitter.com/lukew/status/507880029737328640/photo/1
12. 11 img { max-width: 100%; }
15. 14 A solution: Serve one big image and let the browser scale it
20. 19 Bullet 1 Bullet 2 Bullet 3
21. 20 Bullet 1 Bullet 2 Bullet 3
23. 22 2x resolution = 4x as many pixels 3x resolution = 9x as many pixels 4x resolution = 16x as many pixels
24. 23 more pixels = more energy more pixels = more money more pixels = more time
25. 24 — Dave Rupert , Mo’ Pixels, Mo’ Problems Caption
26. 25 That’s why images.
27. 26 Responsive images
28. 27 A solution: Serve one big image and let the browser scale it
29. 28 A better solution: Serve an appropriate image to each user
33. 32 SVG WebP JPEG XR JPEG 2000
35. 34 Using JavaScript is a bad idea.
36. 35 Using CSS is a bad idea.
37. 36 http://whatwg.org/html#the-picture-element Responsive images specification
38. 37 You can use this now!
39. 38 Firefox (Gecko) Chrome/Opera (Blink) Safari (WebKit) Internet Explorer/ Edge srcset + sizes Works now! Firefox 38 Works now! Chrome 34 Opera 21 Works now! * Safari 6.2 Safari 7.1 iOS 8 In development picture Works now! Firefox 38 Works now! Chrome 38 Opera 25 In development Under consideration
40. 39 http://picturefill.responsiveimages.org/ Picturefill by Scott Jehl & others http://filamentgroup.com/lab/to-picturefill.html To Picturefill, or not to Picturefill
41. 40 Resolution switching Markup
42. 40 Resolution switching Markup
43. 41 <img src="wolf4800.jpg" alt="A rad wolf" />
44. 42 <img src="wolf4800.jpg" alt="A rad wolf" srcset="wolf300.jpg 0.5x, wolf600.jpg 1x, wolf1200.jpg 2x, wolf2400.jpg 3x, wolf4800.jpg 4x" />
45. 43 <img src="wolf4800.jpg" alt="A rad wolf" srcset="wolf300.jpg 0.5x, wolf600.jpg 1x, wolf1200.jpg 2x, wolf2400.jpg 3x, wolf4800.jpg 4x" />
46. 44 <img src="wolf4800.jpg" alt="A rad wolf" srcset="wolf300.jpg 0.5x, wolf600.jpg 1x, wolf1200.jpg 2x, wolf2400.jpg 3x, wolf4800.jpg 4x" />
47. 45 <img src="wolf4800.jpg" alt="A rad wolf" srcset="wolf300.jpg 0.5x, wolf600.jpg 1x, wolf1200.jpg 2x, wolf2400.jpg 3x, wolf4800.jpg 4x" />
48. 46 <img src="wolf600.jpg" alt="A rad wolf" srcset="wolf300.jpg 0.5x, wolf600.jpg 1x, wolf1200.jpg 2x, wolf2400.jpg 3x, wolf4800.jpg 4x" />
49. 47 <img src="wolf600.jpg" alt="A rad wolf" srcset="wolf300.jpg 0.5x, wolf600.jpg 1x, wolf1200.jpg 2x, wolf2400.jpg 3x, wolf4800.jpg 4x" />
50. 48 Viewport (and resolution!) switching Markup
51. 49 <img src="wolf4800.jpg" alt="A rad wolf" />
52. 50 <img src="wolf4800.jpg" alt="A rad wolf" sizes="100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
53. 51 <img src="wolf4800.jpg" alt="A rad wolf" sizes="100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
54. 52 <img src="wolf4800.jpg" alt="A rad wolf" sizes="100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
55. 53 <img src="wolf4800.jpg" alt="A rad wolf" sizes="100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
56. 54 <img src="wolf4800.jpg" alt="A rad wolf" sizes="100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
57. 55 <img src="wolf4800.jpg" alt="A rad wolf" sizes="100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
58. 56 <img src="wolf4800.jpg" alt="A rad wolf" sizes="600px" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
59. 57 <img src="wolf4800.jpg" alt="A rad wolf" sizes="calc(100vw - 10em)" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
60. 58 <img src="wolf4800.jpg" alt="A rad wolf" sizes=“100%" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
62. 60 <img src="wolf4800.jpg" alt="A rad wolf" sizes="(min-width: 1000px) 33vw, (min-width: 600px) 50vw, 100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
63. 61 <img src="wolf4800.jpg" alt="A rad wolf" sizes="(min-width: 1000px) 33vw, (min-width: 600px) 50vw, 100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
64. 62 File type switching Markup
65. 63 <img src="wolf4800.jpg" alt="A rad wolf" />
66. 64 <picture> <source type="image/webp" srcset="wolf4800.webp" /> <img src="wolf4800.jpg" alt="A rad wolf" /> </picture>
67. 65 <picture> <source type="image/webp" srcset="wolf4800.webp" /> <img src="wolf4800.jpg" alt="A rad wolf" /> </picture>
68. 66 <picture> <source type="image/webp" srcset="wolf4800.webp" /> <img src="wolf4800.jpg" alt="A rad wolf" /> </picture>
69. 67 <picture> <source type="image/webp" srcset="wolf4800.webp" /> <img src="wolf4800.jpg" alt="A rad wolf" /> </picture>
70. 68 <picture> <source type="image/webp" srcset="wolf4800.webp" /> <source type="image/vnd.ms-photo" srcset="wolf4800.jxr" /> <img src="wolf4800.jpg" alt="A rad wolf" /> </picture>
71. 69 <picture> <source type="image/webp" srcset="wolf4800.webp" /> <source type="image/vnd.ms-photo" srcset="wolf4800.jxr" /> <img src="wolf4800.jpg" alt="A rad wolf" /> </picture>
72. 70 Art direction Markup
73. 71 —Adventure Time
76. 74 <img src="wolf4800.jpg" alt="A rad wolf" />
77. 75 <picture> <source media="(min-width: 1000px)" srcset="wolf-crop-bg.jpg" /> <source media="(min-width: 600px)" srcset="wolf-crop-sm.jpg" /> <img src="wolf.jpg" alt="A rad wolf" /> </picture>
78. 76 <picture> <source media="(min-width: 1000px)" srcset="wolf-crop-bg.jpg" /> <source media="(min-width: 600px)" srcset="wolf-crop-sm.jpg" /> <img src="wolf.jpg" alt="A rad wolf" /> </picture>
79. 77 <picture> <source media="(min-width: 1000px)" srcset="wolf-crop-bg.jpg" /> <source media="(min-width: 600px)" srcset="wolf-crop-sm.jpg" /> <img src="wolf.jpg" alt="A rad wolf" /> </picture>
80. 78 <picture> <source media="(min-width: 1000px)" srcset="wolf-crop-bg.jpg" /> <source media="(min-width: 600px)" srcset="wolf-crop-sm.jpg" /> <img src="wolf.jpg" alt="A rad wolf" /> </picture>
81. 79 <picture> <source media="(min-width: 1000px)" srcset="wolf-crop-bg.jpg" /> <source media="(min-width: 600px)" srcset="wolf-crop-sm.jpg" /> <img src="wolf.jpg" alt="A rad wolf" /> </picture>
82. 80 All the things! Markup a.k.a. the scary slide
83. 80 All the things! Markup a.k.a. the scary slide
84. 81 <picture> <source type="image/webp" media="(min-width: 1000px)" sizes="33vw" srcset="wolf-crop-big-300.jpg 300w, wolf-crop-big-600.jpg 600w, wolf-crop-big-1200.jpg 1200w, wolf-crop-big-2400.jpg 2400w, wolf-crop-big-4800.jpg 4800w" /> <source type="image/webp" media="(min-width: 600px)" sizes="50vw" srcset="wolf-crop-small-300.jpg 300w, wolf-crop-small-600.jpg 600w, wolf-crop-small-1200.jpg 1200w, wolf-crop-small-2400.jpg 2400w, wolf-crop-small-4800.jpg 4800w" /> <source type="image/webp" sizes="100vw" srcset="wolf-crop-med-300.jpg 300w, wolf-crop-med-600.jpg 600w, wolf-crop-med-1200.jpg 1200w, wolf-crop-med-2400.jpg 2400w, wolf-crop-med-4800.jpg 4800w" /> <source media="(min-width: 1000px)" sizes="33vw" srcset="wolf-crop-big-300.jpg 300w, wolf-crop-big-600.jpg 600w, wolf-crop-big-1200.jpg 1200w, wolf-crop-big-2400.jpg 2400w, wolf-crop-big-4800.jpg 4800w" /> <source media="(min-width: 600px)" sizes="50vw" srcset="wolf-crop-small-300.jpg 300w, wolf-crop-small-600.jpg 600w, wolf-crop-small-1200.jpg 1200w, wolf-crop-small-2400.jpg 2400w, wolf-crop-small-4800.jpg 4800w" /> <source sizes="100vw" srcset="wolf-crop-med-300.jpg 300w, wolf-crop-med-600.jpg 600w, wolf-crop-med-1200.jpg 1200w, wolf-crop-med-2400.jpg 2400w, wolf-crop-med-4800.jpg 4800w" /> <img src="wolf-crop-med-600.jpg" alt="A rad wolf" /> </picture>
85. 82 <img src="wolf600.jpg" alt="A rad wolf" sizes="(min-width: 1000px) 33vw, (min-width: 600px) 50vw, 100vw" srcset="wolf300.jpg 300w, wolf600.jpg 600w, wolf1200.jpg 1200w, wolf2400.jpg 2400w, wolf4800.jpg 4800w" />
86. 83 http://whatwg.org/html#the-picture-element Responsive images specification
87. 84 Responsive images are a pain in the butt
89. 86 https://www.npmjs.com/package/grunt-respimg grunt-respimg
90. 87 $ npm install grunt-respimg --save-dev
91. 88 https://www.npmjs.com/package/grunt- responsive-images-extender/ grunt-responsive-images-extender
92. 89 $ npm install grunt-responsive-images- extender --save-dev
93. 90 https://github.com/nwtn/php-respimg/ php-respimg
94. 91 $ composer require nwtn/php-respimg
95. 92 https://wordpress.org/plugins/ricg- responsive-images/ WP RICG Responsive Images plugin
96. 93 Responsible images
97. 94 1. Responsive images
98. 95 1. Responsive images 2. Image optimization
99. 96 https://imageoptim.com/ ImageOptim https://github.com/toy/image_optim image_optim https://github.com/svg/svgo-gui SVGO-GUI https://github.com/svg/svgo SVGO
100. 97 SetOutputFilter DEFLATE AddOutputFilterByType DEFLATE "image/svg+xml"
101. 98 1. Responsive images 2. Image optimization 3. Deferred image loading
104. 101 http://css-tricks.com/snippets/javascript/lazy-loading-images/ LazyLoad JS scripts and plugins, e.g.:
105. 102 1. Responsive images 2. Image optimization 3. Deferred image loading 4. CDNs & Caching
106. 103 ExpiresActive on ExpiresDefault "access plus 1 month" ExpiresByType image/gif "access plus 1 year" ExpiresByType image/jpeg "access plus 1 year" ExpiresByType image/png "access plus 1 year" ExpiresByType image/svg+xml "access plus 1 year"
107. 104 1. Responsive images 2. Image optimization 3. Deferred image loading 4. CDNs & Caching 5. Appropriate contrast and colour
108. 105 7% 8% 10% 11% 29% 35% April May June July August September
109. 106 7% 8% 10% 11% 29% 35% April May June July August September
111. 108 http://colororacle.org/ Color Oracle
112. 109 September 7% August 8% July 10% June 11% May 29% April 35%
113. 110 1. Responsive images 2. Image optimization 3. Deferred image loading 4. CDNs & Caching 5. Appropriate contrast and colour 6. Text-based alternatives
114. 111 [alt] [aria-describedby], [aria-labelledby] [longdesc] <a> <figcaption> SVG elements and attributes
115. 112 http://www.w3.org/TR/html-alt-techniques/ HTML5: Techniques for providing useful text alternatives http://www.w3.org/WAI/GL/wiki/Using_aria-describedby_to_provide_descriptions_of_images Using aria-describedby to provide descriptions of images http://w3c.github.io/test-results/html-longdesc/cr-report.html longdesc Implementation Report http://www.paciellogroup.com/blog/2013/12/using-aria-enhance-svg-accessibility/ Using ARIA to enhance SVG accessibility http://www.w3.org/WAI/GL/wiki/Using_aria-labelledby_to_provide_a_text_alternative_for_non- text_content Using aria-labelledby to provide a text alternative for non-text content
116. 113 1. Responsive images 2. Image optimization 3. Deferred image loading 4. CDNs & Caching 5. Appropriate contrast and colour 6. Text-based alternatives 7. Fewer images!
117. 114 Performance impact
120. 117 Unoptimized Optimized + Responsive Optimized + Responsive + Lazyload CSS 1 KB 1 KB 1 KB HTML 2 KB 3 KB 3 KB Scripts 29 KB 33 KB 33 KB Images 661 KB 253 KB 87 KB Total 693 KB 290 KB (~58% savings) 119 KB (~83% savings)
121. 118 Browser Unoptimized Optimized + Responsive + Lazyload Firefox (Desktop) 2.2 s 2.0 s Safari (iOS) 2.1 s 1.7 s Average 2.2 s 1.9 s (~14% savings)
123. 120 Accessibility Progressive enhancement Responsive web design Web performance
124. David Newton, St. Michael’s Hospital 121 Improving performance with responsive (and responsible!) images OpenWest, 2015-05-07 Twitter: @newtron Github: @nwtn Email: david@davidnewton.ca Slides: https://github.com/nwtn/pres-respimg-perf-openwest