Practical Responsive Images - from Second Wednesday

Practical
Responsive
Images
http://unsplash.com/

A picture is worth a thousand words…
…but the cost is much greater
http://unsplash.com/

The cost of images
http://en.wikipedia.org/wiki/Wikipedia:Size_comparisons
198,000 Words
http://httparchive.org/interesting.php?a=All&l=Jul%2015%202014
1165kB
Images
Average Bytes per Page by
Content Type (July 2014):
If 1kB is 1024 ASCII characters
6 chars/word
An estimated average word length
is five characters, plus a space,
(1165kB * 1024) / 6 = ~198, 800
(including HTML)
(of a total: 1850kB)
50-60
img requests
per page
Average image
size for JPEG
was 30kB

The cost of images
Pride and Prejudice
apparently contains
122,000
words
http://www.searchlit.org/novels/460.php

The Value of Images
“Pictures have the power to create an emotional response
in the audience, which is worth its weight in gold. An image
can also communicate instantly, as our brain can
interpret them much quicker than text.”
http://www.thoughtmechanics.com/the-importance-of-images-in-web-design/
!
thoughtmechanics.com
“If I’d have to pick one single thing that
would sell a product online, it’s images.”
!
Peep Laja (Conversion Coach)

The Value of Images
Articles with images get 94% more total views
Headshots of customer service reps on a web
page can boost conversion rates by 20%
In an ecommerce site, 67% of consumers say the
quality of a product image is “very important” in
selecting and purchasing a product
Including a Photo and a video in a press
release increases views by over 45%
60% of consumers are more likely to
consider or contact a business when an
image shows up in local search results
http://www.jeremysaid.com/the-jaw-dropping-effect-that-images-can-have-on-your-conversion-rates/
http://www.jeffbullas.com/2012/05/28/6-powerful-reasons-why-you-should-include-images-in-your-marketing-infographic/

Images are powerful
In some studies
10-15x
more viewers look at
and engage with the
content when the
model is looking or
gesturing towards it

Images are powerful
In some studies
10-15x
more viewers look at
and engage with the
content when the
model is looking or
gesturing towards it
http://thinkeyetracking.com/2009/06/cuing-customers-to-look-at-your-key-messages/ Photo courtesy of Christian Hambly

Guess the year?
A lot has changed since 1993

Since first proposed in 1993,
the <img > tag has remained
mostly unchanged….
!
…whereas the rest of the web-world
change quite a bit!

Raster image options
Background-images via CSS
background-image: url('../images/header_800px.jpg');
@include mq($M){
background-image: url('../images/header_1400px.jpg');
}
}
*Stu Robson's media query mixin
.banner{
Foreground images at 100%
!
.item_visuals img{
width: 100%;
}
……does nothing for payload.

…use alternatives
to raster images
if you can…….
!
SVG!
!
icon fonts
http://icomoon.io/

Javascript Image Replacement
using <noscript>, custom data- attributes and .insertAfter($(this))
<noscript data-imageid=‘bag.jpg’ data-small-imageid=‘bag_small.jpg’ data-large-imageid=‘bag_large.jpg’>
<img src=‘bag_small.jpg’ alt='Bag' />
http://allbs.co.uk/2012/05/11/responsive-images-intro/
!
</noscript>
<script>
!
var areawidth = $(window).width();
var widthDownTosmall = 600;
var widthUpToLarge = 1100;
!
$('noscript[data-imageid]').each(function(){
var imageBase=“image/path";
var imageid = $(this).attr("data-imageid");
var imageSmall = $(this).attr("data-small-imageid");
var imageLarge = $(this).attr("data-large-imageid");
if (areawidth <= widthDownTosmall) {imageid = imageSmall; }
if (areawidth >= widthUpToLarge) {imageid = imageLarge; }
$('<img src="' + imageBase + imageid + '"/>').insertAfter($(this));
});
</script>

Enter our heroes:
<picture>
srcset/sizes attributes

Nitty gritty
!
<picture>
<source media="(min-width: 40em)" srcset="apple-big.jpg 1x, apple-big-hd.jpg 2x">
<source srcset="apple-small.jpg 1x, apple-small-hd.jpg 2x">
<img src="apple-fallback.jpg" alt="How do you like them apples?">
</picture>
<img src="apple-fallback.jpg"
srcset="apple-big.jpg 1000w, apple-med.jpg 640w, apple-small.jpg 320w"
sizes="(min-width: 40em) 50vw, 100vw"
alt="How do you like them apples?" />

(As of : June 11th ‘14)
Progress
(As of : August 17th ‘14)
http://responsiveimages.org/

How to enable
chrome://flags/#enable-experimental-
web-platform-features
Firefox Nightly
Tools > Web Developer >
Developer Toolbar
Chrome Canary

*BREAKING NEWS*
Chrome 38 released 7th Oct
!
First stable browser with
<picture> enabled by default!

Can I Use
(As of : Aug 16th 2014)
http://caniuse.com/#search=picture http://caniuse.com/#search=srcset

picturefill
A responsive image polyfill.
For today, and future-legacy-browsers
http://scottjehl.github.io/picturefill/
<script>
document.createElement( "picture" );
</script>
<script src="picturefill.js" async></script>
Developed and maintained by Filament Group

grab a copy of picturefill.js
Use the <picture> element
!
*IE9 needs a bit of a workaround to avoid a conflict:
<picture>

<source srcset="/image1_big.jpg" media="(min-width: 1000px)">
<source srcset="/image1_medium.jpg" media="(min-width: 800px)">
<source srcset="/image_small.jpg">

<img srcset="/image_fallback.jpg alt="context">
</picture>
Try it today

Use Case 1: breakpoint optimised images (retina/pixel ratio)
media="(min-width: 1000px)"
media="(min-width: 400px)"
srcset="/image1_big.jpg"
srcset=“/image1_small.jpg"
http://responsiveimag.es/Practical_Example_1.html

Use Case 1: srcset, without sizes (assumes 100vw)
<img
srcset=“Apple_800.jpg 800w,
Apple_1200.jpg 1200w"
src=“Apple_fallback.jpg”
alt=“How do you like them Apples?"/>
</div>

Use Case 2: Crop to point of interest (Art Direction)

Use Case 3: Device Orientation
srcset="landscape_variant.jpg" media="(min-width:
400px) and (orientation: landscape)"
srcset="portrait_variant.jpg" media="(min-width:
400px) and (orientation: portrait)"

Use Case 4: Image type : webp/svg
<picture>
<type="image/webp" srcset="images/lilypad_600.webp" />
<img src="images/lilypad_600.jpg" alt="Lily pad" />
</picture>

Use Case 5: vw
<img
src=“Apple_fallback.jpg” alt="How do you like them Apples?"
sizes="(min-width: 640px) 50vw, 100vw"
srcset=“Apple_200.jpg 200w,
Apple_400.jpg 400w,
Apple_600.jpg 600w,
Apple_800.jpg 800w,
Apple_1200.jpg 1200w" />
</div>
Viewport width
If width ≥ 640px then use 50vw
!
i.e. Calculations use 50% of width
50%
Within the fluid context of responsive websites,
the restrictive nature of the <img> element, and
lack of CSS controls for foreground images, has
not been the elephant in the room. It's just been
the elephant that we couldn't agree what to do
with….

Where do we get all those image variants?
(scaling / CDN)
Batch Statics
v
Server-side
image manipulation
Build Your Own
v
SaaS

Dynamic Imaging Systems
At-request-time image variants:
Control width, quality, sharpening….
!
image.jpg?w=400&qlt=70&unsharp=0,1,1,7

Combining the two
<picture>

<source srcset="http://images.amplience.com/i/benco/Apple_Row2.jpg?
w=1400&qlt=80&unsharp=0,1,1,7" media="(min-width: 1200px)">
<source srcset=“http://images.amplience.com/i/benco/Apple_Row2.jpg?
w=1200&qlt=80&unsharp=0,1,1,7" media="(min-width: 1050px)">
pcrop=700,0,2500,800&w=950&qlt=80&unsharp=0,1,1,7" media="(min-width: 850px)">
pcrop=1300,0,1900,800&w=850&qlt=80&unsharp=0,1,1,7" media="(min-width: 600px)">
<source srcset=“http://images.amplience.com/i/benco/Red_And_Green_Apples2.jpg?
w=600&qlt=80&unsharp=0,1,1,7">
<img srcset="http://images.amplience.com/i/benco/Apple2.jpg?w=600&qlt=80"
alt="How do you like them Apples?">
</picture>

Combining the two
<img
src="http://images.amplience.com/i/benco/Apple2.jpg?w=400&qlt=80"
Viewport width
50%
Within the fluid context of responsive websites,
the restrictive nature of the <img> element, and
lack of CSS controls for foreground images, has
not been the elephant in the room. It's just been
the elephant that we couldn't agree what to do
with….
alt="How do you like them Apples?"
sizes="(min-width: 640px) 50vw, 100vw"
srcset="http://images.amplience.com/i/benco/Apple_Row2.jpg?w=200&qlt=80&unsharp=0,1,1,7 200w,
http://images.amplience.com/i/benco/Apple_Row2.jpg?w=400&qlt=80&unsharp=0,1,1,7 400w,
http://images.amplience.com/i/benco/Apple_Row2.jpg?w=1200&qlt=80&unsharp=0,1,1,7 1200w" />
!
</div>

AngularJS
<body>
<img src=“Apple.jpg" picture-assetid="Apple_Row2"
alt="How do you like them apples?"/>
</body>
angular.module('components', [])
.directive('pictureAssetid', function(){
return {
restrict: 'A',
replace:true,
transclude: true,
scope : {
caption: '@',
pictureAssetid: '@'
},
templateUrl: 'partials/image-picture.html'
}
})
!
angular.module('HelloApp', ['components'])
<picture>

<source srcset="http://images.amplience.com/i/benco/{{pictureAssetid}}.jpg?w=1400&qlt=80&unsharp=0,1,1,7" media="(min-width: 1000px)">
<source srcset="http://images.amplience.com/i/benco/{{pictureAssetid}}.jpg?w=800&qlt=80&unsharp=0,1,1,7" media="(min-width: 800px)">
<source srcset="http://images.amplience.com/i/benco/{{pictureAssetid}}.jpg?w=600&qlt=80&unsharp=0,1,1,7">
<img srcset="http://images.amplience.com/i/benco/{{pictureAssetid}}.jpg?w=400&qlt=80" >
</picture>

<picture>
/
srcset
Dynamic
Imaging
System
Practical
Responsive
Images
+ =

responsiveimag.es
@bseymour
Thank you

Practical Responsive Images - from Second Wednesday

More Related Content

What's hot (11)

Viewers also liked (9)

Similar to Practical Responsive Images - from Second Wednesday (20)

More from Ben Seymour (8)

Recently uploaded (20)

Practical Responsive Images - from Second Wednesday