visionary-url v1.2.0
Visionary URL is a lightweight Typescript library for generating image URLs with built-in Blurhash placeholders.
Getting started
Install visionary-url
via npm. Both ES modules and CommonJS modules are supported.
npm install --save visionary-url
Generating a Visionary URL
import { generateVisionaryUrl } from 'visionary-url';
const url = generateVisionaryUrl({
blurhash: "LCDJYN9FxG_M_N%L%M%M4o~ptRIA", // blurhash string
blurhashX: 4, // blurhash x components
blurhashY: 4, // blurhash y components
bcc: "#baccae", // background color code
fileId: "image:101", // image ID or URL
sourceHeight: 1200, // image height
sourceWidth: 1600, // image width
});
How it works
A Visionary URL is formatted using 3 or 4 URL segments:
| | base path | | visionary code | | options (optional) | | filename |
| -- | -- | -- | -- | -- | -- | -- | -- |
| /
| image
| /
| <visionary code, base64url>
| /
|<option tokens>
| /
| image.jpg
|
Example URLs
https://examplecdn.cloud/image/aW1hZ2U6MTAwMDEhODAwITYwMA/image.jpg
https://examplecdn.cloud/image/aW1hZ2U6MTAwMDEhODAwITYwMA/4k/image.jpg
Visionary code
The Visionary code is a base64url'd, exclamation-point separated list of image placeholder data, detailed as the following:
Attribute | Description |
---|---|
Image ID | Image URL or internal image ID (required) |
Image width | Used to compute aspect ratio of image placeholder (required) |
Image height | Used to compute aspect ratio of image placeholder (required) |
Background color code | Base layer background color code (e.g. #BACCAE ) |
Blurhash code | Blurhash string of the image |
Blurhash x components | Number of x components the blurhash code represents |
Blurhash y components | Number of y components the blurhash code represents |
Image options
Image options are optional and are provided as comma separated tokens.
Size token
One of the following tokens may be included in the options string to specify an image size: xs
, sm
, md
, lg
, xl
, xxl
, 4k
, 5k
Download token
token | description |
---|---|
download | Indication for server to return content-disposition: attachment; in response headers |