Images
Image Formats
Image Formats
Raster vs Vector
Raster - Image data stored as "pixels."
- DPI - "dots per inch" is typically 300 for print, 72 for web (but doesn't matter).
- Retina / "high DPI" - 2 pixels for every 1
- Blurry when enlarged
- Program of Choice: Adobe Photoshop
- Best Formats: PNG & JPEG
Image Formats
Raster vs Vector
Vector - Draw shapes with math
- Use math to draw shapes using points, lines and curves
- Typically used for fonts and logos
- Program of choice: Adobe Illustrator
- Format of choice: SVG
Image Formats
Raster vs Vector
Image via tutorialspark.com
JPG / JPEG
- Raster
- "Joint Photographic Experts Group"
- Up to 10:1 compression
- Best when many colors are present with smooth variations between the colors, like a photo or painting.
PNG
- Raster
- "Portable Network Graphics"
- Different compression levels:
- 8-bit (256 colors)
- 24-bit RGB
- 32-bit RGBA
- A = Alpha (transparency)
- Best for icons, logos, or when you need to use transparency (example)
webcomic via lbrandy.com
GIF
- "Graphic Interchange Format"
- 8-bit (256 colors)
- Supports animation, but video formats (MPEG / WEBM) have better compression.
SVG
<svg height="210" width="400">
<path d="M150 0 L75 200 L225 200 Z" />
</svg>
Additional Formats
-
TIFF - uncompressed (don't use)
-
BMP - BitMap - similar to JPG but less efficient
-
WEBP - Web Picture, great compression but not supported across all browsers (caniuse.com/webp)
Image via http://superuser.com/a/296437a
Let's prepare an img
Adobe Photoshop --> preferred
pixlr.com/editor --> free online editor
Image Copyright
Everything is Copyrighted unless it tells you otherwise
Creative Commons
- Copyright, but allows certain uses.
- Three Variables:
- Commercial / NonCommercial
- Attribution
- Derivatives (No Derivatives / Share Alike)
- More info: creativecommons.org/licenses/
Resources page 1
Flickr advanced search
http://littlevisuals.co/
http://www.lifeofpix.com/
http://images.superfamous.com/
https://picjumbo.com/
http://www.nypl.org/research/collections/digital-collections/public-domain
http://deathtothestockphoto.com/
https://search.creativecommons.org/
http://www.imcreator.com/free
http://getrefe.tumblr.com/
http://lockandstockphotos.com/
http://snapwiresnaps.tumblr.com/
http://jaymantri.com/
Resources page 2
StockSnap, Unfinished Business, Free Nature Stock, Stock Up, Pexels, All The Free Stock, Unsplash, Travel Coffee Book , Splashbase, Startup Stock Photos, Designers Pics, Foodie’s Feed, Jéshoots, Death to the Stock Photo, Pixabay, Picography, Magdeleine, Snapographic, Splitshire, New Old Stock, Picjumbo, Life of Pix, Gratisography, Getrefe, IM Free, ISO Republic, Kaboompics, Function, MMT, Paul Jarvis, Lock & Stock Photos, Raumrot, StockSnap, Free Nature Stock, Mazwai
<img>
<img src="images/image.jpg" alt="if image does not display" title="description on hover">
Semantic IMG
<figure>
<img src="img/album-eno.jpg" alt="Another Green World album cover" title="Another Green World">
<footer>
<!-- copyright typically goes in a small tag in a footer -->
<small class="copyright">© Island Records, 1975</small>
</footer>
<figcaption>
Another Green World by Brian Eno.
Cover art is detail from the Tom Phillips painting
<cite>After Raphael</cite>)
</figcaption>
</figure>
<picture>
- Container for Responsive Images
- Browser loads the image that best fits the screen size
- Example via html5rocks
<picture>
<source
media="(min-width: 650px)"
srcset="images/kitten-stretching.png">
<source
media="(min-width: 465px)"
srcset="images/kitten-sitting.png">
<img
src="images/kitten-curled.png"
alt="a cute kitten">
</picture>
CSS: background-image
body {
background-image: url('img/myimg.png');
background-repeat:repeat;
background-size:50px;
}
Data URL
HTML/CSS Images
By Jason Sigal
HTML/CSS Images
- 3,477