on-the-fly-media-optimization-and-dynamic-image-manipulation.md

description
Zesty.io's DAM has on-the-fly (OTF) rendering options to improve and manipulate media that both developers and content authors can use.

On-The-Fly Media Optimization and Dynamic Image Manipulation

Auto Image Optimization - Default Output

Zesty.io automatically transforms images as the content-type "webp", which is a format made to optimized image download speed and rendering speed, developed by Google.

WebP is a modern image format that provides superior lossless and lossy compression for images on the web. Using WebP, webmasters and web developers can create smaller, richer images that make the web faster. - Read the full Google launch article https://developers.google.com/speed/webp

When optimization happens, Zesty.io does a few things to the file:

• All metadata (for example, EXIF, XMP, or ICC) will is removed.
• Any ICC profile on the image is applied directly to the image to ensure color output is correct. If the image doesn't have an ICC profile, a default profile is added.
• If the source image contains orientation metadata, this orientation will be applied directly to the image data and metadata will be removed.
• Images are served with their original name and extension, but will still output as content-type "webp"

OTF DAM Quick Examples

<!-- using the direct media url, append query parameters to the url --> 
<img src="https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?width=200" alt="space ship example">
<!-- using parsley, append query paramters outside th call -->
<img src="{{this.image.getImage()}}?width200&crop=1:1" alt="parsley example">

<!-- example using src set images to be used at different display pixel densities -->
<img srcset="{{this.image.getImage()}}?width=320&dpr=1.5 1.5x,
             {{this.image.getImage()}}?width=320&dpr=2 2x"
     src="{{this.image.getImage()}}?width=320"/>
     
<!-- HTML5 art direction, use different images based on browser width -->
<picture>
  <source srcset="{{this.image.getImage()}}?width=600&crop=16:9" media="(min-width: 600px)"/>
  <img src="{{this.image.getImage()}}?width=320&crop=1:1"/>
</picture>

<style>
  .header {
    background-image: url(https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?width=2000)
  }
</style>

Bypass Image Optimization

To bypass image optimization to get the raw encoding and data of the origin image, append ?raw=true to the end of the image request like so:

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?raw=true

This is useful for fetching EXIF data or other meta data hidden in your image file.

Image Manipulation Options

All image may be manipulated on-the-fly by passing query parameter to the end of the image URL. See the example below

Query Param	Example
none	https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg
?width=	https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?width=300
?orient=	https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?orient=v
?bg-color=	https://9skdl6.media.zestyio.com/parsley-logo-brackets.png?bg-color=006699

We recognize the following parameters in the query string of the image request:

Parameter	Description
auto	Enable optimization features automatically.
bg-color	Set the background color of an image.
bypass	Ignore all optimization and fetch the raw original image
blur	Set the blurriness of the output image.
brightness	Set the brightness of the output image.
canvas	Increase the size of the canvas around an image.
contrast	Set the contrast of the output image.
crop	Crop an image by removing pixels from an image based on a ratio. Great for thumbnails.
dpr	Device Pixel Ratio - Serve correctly sized images for devices that expose a device pixel ratio.
fit	Set how the image will fit within the width and height provided.
height	Resize the height of the image.
optimize	Automatically apply optimal quality compression.
orient	Change the cardinal orientation of the image.
pad	Add pixels to the edge of an image, like css padding.
quality	Optimize the image to the given compression level for lossy file formatted images.
saturation	Set the saturation of the output image.
sharpen	Set the sharpness of the output image.
trim	Remove pixels from the edge of an image.
width	Resize the width of the image.

Image Manipulation Processing order

Manipulation query parameters can be specified in any order, but they are processed in this order:

Order	Query Call
1	trim
2	crop
3	orient
4	width height dpr fit
5	pad canvas bg-color
6	brightness contrast saturation
7	sharpen
8	blur
9	auto optimize quality profile level

Zesty.io OTF DAM: On-The-Fly Image Options API

All query parameters listed below may be used in conjunction with one another, and may be stacked. Some query params conflict with each other, for example pad and canvas. This behavior is documented under each example API call.

Auto Optimize: /image.jpg?auto=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?auto=webp

Enables optimizations based on content negotiation. Although the WebP format produces images at a higher compression ratio with a lower loss of quality, it is not supported in all browsers.

?auto=webp Deliver lossless (because input image is lossless) WebP where client support is available, otherwise deliver a PNG
?format=pjpg&auto=webpDeliver lossy (because format=pjpg is lossy) WebP where client support is available, otherwise deliver a progressive JPEG
?format=png&auto=webp Deliver lossless (because format=png is lossless) WebP where client support is available, otherwise deliver a PNG

Query Parameters

Name	Type	Description
auto	string	webp is the only option, see notes above

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?format=pjpg&auto=webp

{% endtab %} {% endtabs %}

Background Color: /image.jpg?bg-color=

GET https://9skdl6.media.zestyio.com/parsley-logo-brackets.png?bg-color=690167

Change the background color of a transparent image. Tip: you can make background transparent using a decimal value on the end like 125,80,200,0.5

Query Parameters

Name	Type	Description
bg-color	string	Hex RBG: 690167Decimal: 105,1,103,0.5

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/parsley-logo-brackets.png?bg-color=006699

{% endtab %} {% endtabs %}

Bypass: /image.jpg?raw=true

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?raw=true

Bypass any optimization and return the original image.

Query Parameters

Name	Type	Description
raw	string	true

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?raw=true

{% endtab %} {% endtabs %}

Gaussian Blur: /image.jpg?blur=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?blur=20

Gaussian blur your image.

Query Parameters

Name	Type	Description
blur	number	0.5 to 1000

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?blur=20

{% endtab %} {% endtabs %}

Brightness: /image.jpg?brightness=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?brightness=20

Adjusts the "brightness" of an image. This effect adds perceived light to an image.

Query Parameters

Name	Type	Description
brightness	integer	0 unchanged || -100 black || 100 white

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?brightness=20

{% endtab %} {% endtabs %}

Canvas

Canvas is used for advanced targeted cropping of images.

The canvas image modifier query parameter takes multiple values which can get complicated, so we included example references as they are best to understand the behavior. To get a feel for it, experiment with the image url example provided, and play with the numbers.

The canvas query param takes comma separated values SIZE,POSITION, where SIZE is a pixel width and height 500,100or a ratio like 2:1. The POSITION is represented as a percentage offset from the center of the image using offset-x and offset-ylike offset-x50,offset-y95 . POSITION and SIZE together look like this:canvas=400,130,offset-x50,offset-y95. If POSITION is omitted, the image centers by default.

• The background color of the canvas will default to transparency for image output formats that support transparency and white for formats that don't. This behavior can be changed by adding the bg-color parameter.
• When using canvas and pad at the same time, pad will be ignored.
• Fractional pixel measurements are rounded to the nearest whole pixel.

Canvas Control: /image.jpg?canvas=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?canvas=500,100

Allows the user to precisely crop an image by specific positions as described above.

Query Parameters

Name	Type	Description
canvas	string	See above documentation

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Contrast: /image.jpg?contrast=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?contrast=20

Change the image contrast, the value can be anything between -100 and 100, negative numbers start to wash out the image, positive number increase the vibrancy of the images colors.

Query Parameters

Name	Type	Description
contrast	integer	-100 to 100

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?contrast=100

{% endtab %} {% endtabs %}

Crop: /image.jpg?crop=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?crop=1:1

Crop an image evenly from all sides by passing in a ratio 1:1 is a perfect square, 16:9 is letter box, 10:1 is a slim rectangle etc. Great for making thumbnails by passing in a width and a crop, ?crop=1:1&width=50 makes a tiny square, for example.

To crop before other commands are run, use precrop instead of crop

Query Parameters

Name	Type	Description
precrop	string	use over crop when needed before other changes
crop	string	1:1 || 10:1 || 16:9

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?crop=1:1&width=400

{% endtab %} {% endtabs %}

Device Pixel Ratio (dpr): /image.jpg?dpr=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?dpr=2

For optimizing delivery of images to devices with high pixel ratios. The iPhone XS, for example, has a resolution of 375x812 pixels, but its device to pixel ration is 3, so it renders 1125x2436. A developer can access this value from JavaScript by calling window.devicePixelRatio

DPR will increase the delivered size by a multiple 1-10 to accommodate for the device Pixel Ratio. Use with JavaScript dynamically when rendering a view and you know the clients Device Pixel Ratio.

Query Parameters

Name	Type	Description
dpr	number	1-10

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Fit: /image.jpg?fit=cover&height=200&width=200

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?fit=cover&height=200&width=200

The fit parameter controls how the image will be constrained within the provided size (width and height) values, in order to maintain proportions that fit within the confines of the width and height.

Note: width and height must be pass with fit to work properly. Use the the navigation on the right to search on width and height. An example of this is image.jpg?fit=cover&height=200&width=200

bounds fit entirely within the specified region, making one dimension smaller if needed.

cover cover the specified region, making one dimension larger if needed.

crop Resize and crop the image centrally to exactly fit the specified region.

Query Parameters

Name	Type	Description
fit	string	bounds || cover || crop
width	number	width in pixels
height	number	height in pixels

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Height: /images.jpg?height=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?height=200

Control the height of the image, the width, if not provided, will adapt to match the original ratio of the image.

Query Parameters

Name	Type	Description
height	number	A height in pixels

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?height=100

{% endtab %} {% endtabs %}

Image Optimize /image.jpg?optimize=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?optimize=high

Difference and output are minimal for most images that use this param, to be more aggressive in sizing, use the QUALITY param.

log Output image quality will be similar to the input image quality.
medium More optimization is allowed. Visual quality of the input is preserved.
high Minor visual artifacts may be visible. This produces the smallest file.\

Query Parameters

Name	Type	Description
optimize	string

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Orientation: /image.jpg?orient=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?orient=l

Rotate the image on 90 degree angles
r Orient the image right.
l Orient the image left.
h Flip the image horizontally.
v Flip the image vertically.
hv Flip the image both horizontally and vertically (also vh).
rv Flip the image horizontally, then orient the image left (also rv or vr).
vl Flip the image horizontally, then orient the image right (also lvor vl).

Query Parameters

Name	Type	Description
orient	string	see above docs for options

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?orient=l

{% endtab %} {% endtabs %}

Image Padding: /image.jpg?pad=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?pad=10,20,50,10

Add extra pixels around an image by following the same standards as the CSS padding attribute.

For example:
top, right, bottom, left: 10,20,10,20
single number to get even all around: 100
top bottom and left and right as: 100,200

Tip: combine with bg-color to change the padding color

Query Parameters

Name	Type	Description
pad	string	100,20,200,111

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Image Quality: /image.jpg?quality=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?quality=55

Control the file size of the image by reducing the quality.

Path Parameters

Name	Type	Description
	string

{% tabs %} {% tab title="200 https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?quality=55" %}

{% endtab %} {% endtabs %}

Saturation: /image.jpg?saturation=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?saturation=-50

Play with the intensity levels of colors, also use to grayscale an image by passing -100

Path Parameters

Name	Type	Description
	string	-100 for grayscale 0 is normal 100 is intense

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Sharpen: /image.jpg?sharpen

GET https://9skdl6.media.zestyio.com?sharpen=a5,r5,t4

Change the sharpness of an image, which can create really interesting artistic outputs

amount:0-10, radius:0-1000, and threshold:0-100\

Path Parameters

Name	Type	Description
	string	aX,rX,tX where X is an integer

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?sharpen=a5,r5,t4

{% endtab %} {% endtabs %}

Trim /image.jpg?trim=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?trim=25,50,75,100

Values are accept the same as CSS padding or margin values. The numbers may be pixels or percentages. Pixel value example: 25,50,75,100 Percentage example 25p,50p,20p,10p

Path Parameters

Name	Type	Description
	string

{% tabs %} {% tab title="200 " %}

{% endtab %} {% endtabs %}

Width: /image.jpg?width=

GET https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?width=100

Constrain the width of the image, the height, if not passed, will auto size itself to the original ratio of thr image.

Query Parameters

Name	Type	Description
width	number	Integer

{% tabs %} {% tab title="200 " %}

https://9skdl6.media.zestyio.com/Arcade-Space-Ship-Example.jpg?width=800

{% endtab %} {% endtabs %}

About Zesty.io On-The-Fly Media Technology

Zesty.io leverages Fastly's Image Optimization technology layered on top of the Zesty.io DAM Media Manager. Features documented here relate to what is supported through Zesty.io WebEngine and Media services.