Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/derhuerst/gulp-scale-images
Gulp plugin to resize each image into multiple smaller variants.
https://github.com/derhuerst/gulp-scale-images
gulp gulp-plugin image picture resize scale sharp
Last synced: 5 days ago
JSON representation
Gulp plugin to resize each image into multiple smaller variants.
- Host: GitHub
- URL: https://github.com/derhuerst/gulp-scale-images
- Owner: derhuerst
- License: isc
- Created: 2018-03-22T00:52:37.000Z (over 6 years ago)
- Default Branch: master
- Last Pushed: 2024-02-22T15:33:25.000Z (9 months ago)
- Last Synced: 2024-05-01T23:29:36.938Z (7 months ago)
- Topics: gulp, gulp-plugin, image, picture, resize, scale, sharp
- Language: JavaScript
- Homepage: https://github.com/derhuerst/gulp-scale-images#gulp-scale-images
- Size: 587 KB
- Stars: 12
- Watchers: 2
- Forks: 5
- Open Issues: 3
-
Metadata Files:
- Readme: readme.md
- License: license.md
Awesome Lists containing this project
README
# gulp-scale-images
**[Gulp](https://gulpjs.com) plugin to make each image smaller. Combined with [`flat-map`](https://npmjs.com/package/flat-map), you can create multiple variantes per image**, which is useful for [responsive images](https://developer.mozilla.org/en-US/docs/Learn/HTML/Multimedia_and_embedding/Responsive_images).
[](https://www.npmjs.com/package/gulp-scale-images)
[](https://travis-ci.org/derhuerst/gulp-scale-images)
[](https://github.com/sponsors/derhuerst)
[](https://twitter.com/derhuerst)
## Installing
```shell
npm install gulp-scale-images --save-dev
```
## Usage
`gulp-scale-images` expects the instructions for each file to be in `file.scale`. They may look like this:
```js
{
maxWidth: 300, // optional maximum width
maxHeight: 400, // optional maximum height
format: 'jpeg', // optional, one of ('jpeg', 'png', 'webp')
withoutEnlargement: false, // optional, default is true
fit: 'inside', // optional, default is 'cover', one of ('cover', 'contain', 'fill', 'inside', 'outside')
rotate: true, // optional
metadata: false, // copy metadata over?
formatOptions: {} // optional, additional format options for sharp engine
}
```
*Note*: You must specify at least one of `maxWidth` and `maxHeight`.
You can pass additional format options to Sharp engine using `formatOptions` parameter. Docs can be found at [Sharp API](http://sharp.pixelplumbing.com/en/stable/api-output/).
An example, we're going to generate *two* smaller variants for each input file. We're going to use [`flat-map`](https://npmjs.com/package/flat-map) for this:
```js
const gulp = require('gulp')
const flatMap = require('flat-map').default
const scaleImages = require('gulp-scale-images')
const twoVariantsPerFile = (file, cb) => {
const pngFile = file.clone()
pngFile.scale = {maxWidth: 500, maxHeight: 500, format: 'png'}
const jpegFile = file.clone()
jpegFile.scale = {maxWidth: 700, format: 'jpeg'}
cb(null, [pngFile, jpegFile])
}
gulp.src('src/*.{jpeg,jpg,png,gif}')
.pipe(flatMap(twoVariantsPerFile))
.pipe(scaleImages())
.pipe(gulp.dest(…))
```
*Note:* Unlike `sharp`, `gulp-scale-image` is *not* designed to process untrusted user input. For example, it turns off `sharp`'s [input pixel limit](https://github.com/lovell/sharp/issues/1381#issuecomment-423182487) altogether.
### Definining scale instructions based on metadata
You can let `gulp-scale-images` read the image metadata first, to device what to do with the file:
```js
const readMetadata = require('gulp-scale-images/read-metadata')
const through = require('through2')
const scaleImages = require('gulp-scale-images')
const computeScaleInstructions = (file, _, cb) => {
readMetadata(file, (err, meta) => {
if (err) return cb(err)
file = file.clone()
file.scale = {
maxWidth: Math.floor(meta.width / 2),
maxHeight: Math.floor(meta.height / 2)
}
cb(null, file)
})
}
gulp.src(…)
.pipe(through.obj(computeScaleInstructions))
.pipe(scaleImages())
.pipe(gulp.dest(…))
```
### Custom output file names
By default, `gulp-scale-images` will use `{basename}.{maxWidth}w-{maxHeight}h.{format}` (e.g. `foo.500w-300h.jpeg`). You can define a custom logic though:
```js
const path = require('path')
const scaleImages = require('gulp-scale-images')
const computeFileName = (output, scale, cb) => {
const fileName = [
path.basename(output.path, output.extname), // strip extension
scale.maxWidth + 'w',
scale.format || output.extname
].join('.')
cb(null, fileName)
}
gulp.src(…)
.pipe(through.obj(computeScaleInstructions))
.pipe(scaleImages(computeFileName)) // not that we pass computeFileName here
.pipe(gulp.dest(…))
```
### `gulp-scale-images` works well with
- [`flat-map`](https://www.npmjs.com/package/flat-map) – A flat map implementation for node streams. (One chunk in, `n` chunks out.)
- [`replace-ext`](https://www.npmjs.com/package/replace-ext) – Replaces a file extension with another one.
## Similar libraries
Some similar libraries and why I think this one is better.
- [`gulp-image-resize`](https://www.npmjs.com/package/gulp-image-resize)
- uses [`gm`](https://npmjs.com/package/gm) instead of [`sharp`](https://npmjs.com/package/sharp), requires `gm` to be installed
- supports only one scale instruction
- [`gulp-sharp`](https://www.npmjs.com/package/gulp-sharp)
- is not being maintained
- has no tests
- supports only one scale instruction
- [`gulp-retinize`](https://www.npmjs.com/package/gulp-retinize)
- doesn't seem to be maintained
- uses [`gm`](https://npmjs.com/package/gm) instead of [`sharp`](https://npmjs.com/package/sharp), requires `gm` to be installed
- only works for files on disk
- supports only one scale instruction
- [`gulp-imgconv`](https://www.npmjs.com/package/gulp-imgconv)
- has no tests
- supports only one scale instruction
- [`gulp-inline-resize`](https://www.npmjs.com/package/gulp-inline-resize)
- doesn't do *one thing*
- uses [`gm`](https://npmjs.com/package/gm) instead of [`sharp`](https://npmjs.com/package/sharp), requires `gm` to be installed
- [`gulp-unretina`](https://www.npmjs.com/package/gulp-unretina)
- less flexible
- uses [`gm`](https://npmjs.com/package/gm) instead of [`sharp`](https://npmjs.com/package/sharp), requires `gm` to be installed
- [`gulp-gm-limit`](https://www.npmjs.com/package/gulp-gm-limit)
- doesn't seem to be maintained
- supports only one scale instruction
- [`gulp-imgresize`](https://www.npmjs.com/package/gulp-imgresize)
- no documentation
- is not being maintained
- has no tests
## Contributing
If you have a question or have difficulties using `gulp-scale-images`, please double-check your code and setup first. If you think you have found a bug or want to propose a feature, refer to [the issues page](https://github.com/derhuerst/gulp-scale-images/issues).