A nodeJS library that manipulates images on the fly.
You can think of it as an image proxy that also manipulates images based on parameters added to the URL.
Let's take this image:
https://mysite.com/path/to/image.jpg
Here we have https://mysite.com as the image host and /path/to/image.jpg as the path to the image.
Now we have this tool running on https://img.mysite.com, we can just proxy the image:
https://img.mysite.com/path/to/image.jpg
or we can also crop and resize it to 500x500px and grayscale it:
https://img.mysite.com/size-500x500/transform[grayscale]/path/to/image.jpg
The image will be generated on the frst request, then it's cached and will be served from the cache directly from the second request on.
The config is mainly based on ENV Vars:
PORT: The port where the server should runIMAGES_FOLDER: The folder where images should be cachedIMG_HOST: The origin host of the image
Images can be resized and cropped. Therefore it exepts an URL parameter prefixed with size-:
/size-{width}x{height}/
/size-500x500/
/size-500x0/
/size-0x500/
You can set 0 for width or height. That means it will keep the ratio and only chage what's specified.
Images can be transformed with a second URL parameter prefixed with transform.
/transform[{function},{value: optional}]/
/transform[blur,20][grayscale]/
Flip the image horizontally or vertically:
[flip,v] flip vertically
[flip,h] flip horizontally
[flip,vh] flip vertically and horizontally
Rotates the image clockwise by a number of degrees.
[rotate,{0 - 365}]
adjust the brighness
[brightness,{-100 - 100}]
adjust the contrast
[contrast,{-100 - 100}]
ordered dithering of the image and reduce color space to 16-bits (RGB565)
[dither565]
remove colour from the image
[grayscale]
invert the image colours
[invert]
Gaussian blur the image by r pixels
[gaussian,{r}]
fast blur the image by r pixels
[blur,{r}]
change the quality of the image
[quality,{0 - 100}]