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

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

C3e8ba214714b1402f3073334249fcdc?s=128

newtron

May 07, 2015
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  1. 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. 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)
  3. 7.

    7

  4. 8.

    “ 8 More human beings today have access to a

    cellphone than…a clean toilet. –Anand Giridharadas, New York Times April 10 2010
  5. 9.

    “ 8 More human beings today have access to a

    cellphone than…a clean toilet. –Anand Giridharadas, New York Times April 10 2010
  6. 13.

    12

  7. 14.

    13

  8. 16.

    15

  9. 17.

    16

  10. 18.

    17

  11. 19.

    18

  12. 22.

    21

  13. 23.

    22 2x resolution = 4x as many pixels 3x resolution

    = 9x as many pixels 4x resolution = 16x as many pixels
  14. 24.

    23 more pixels = more energy more pixels = more

    money more pixels = more time
  15. 30.

    29

  16. 31.

    30

  17. 32.

    31

  18. 34.

    33

  19. 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
  20. 44.
  21. 45.
  22. 46.
  23. 47.
  24. 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" />
  25. 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" />
  26. 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" />
  27. 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" />
  28. 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" />
  29. 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" />
  30. 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" />
  31. 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" />
  32. 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" />
  33. 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" />
  34. 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" />
  35. 61.

    59

  36. 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" />
  37. 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" />
  38. 74.

    72

  39. 75.

    73

  40. 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>
  41. 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>
  42. 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>
  43. 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>
  44. 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>
  45. 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>
  46. 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" />
  47. 88.

    85

  48. 102.

    99

  49. 103.

    100

  50. 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"
  51. 107.

    104 1. Responsive images 2. Image optimization 3. Deferred image

    loading 4. CDNs & Caching 5. Appropriate contrast and colour
  52. 108.
  53. 109.
  54. 110.

    107

  55. 113.

    110 1. Responsive images 2. Image optimization 3. Deferred image

    loading 4. CDNs & Caching 5. Appropriate contrast and colour 6. Text-based alternatives
  56. 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
  57. 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!
  58. 118.

    115

  59. 119.

    116

  60. 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)
  61. 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)
  62. 122.

    119

  63. 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