Imgry is an on-demand image delivery web service for responsive applications.

First install Go 1.4+ and copy the etc/imgry.conf.sample (the default is fine), then..

cd imgry/
make tools
make deps
make build
./bin/imgry-server -config=etc/imgry.conf

Open browser to:

http://localhost:4446/mybucket?url=http://i.imgur.com/vEZy2Oh.jpg

this will download the image from the source, cache it, persist it, and return the sized image (in this case, with zero sizing) to the client.

Now, some other variations:

Scale to 300x

http://localhost:4446/mybucket?url=http://i.imgur.com/vEZy2Oh.jpg&size=300x

Resize to exactly 300x300

http://localhost:4446/mybucket?url=http://i.imgur.com/vEZy2Oh.jpg&size=300x300

Resize to 300x300 and maintain aspect ratio

http://localhost:4446/mybucket?url=http://i.imgur.com/vEZy2Oh.jpg&size=300x300&op=cover

Same as above with a cropbox at points (x1:10%,y1:10%) to (x2:90%,y2:90%)

http://localhost:4446/mybucket?url=http://i.imgur.com/vEZy2Oh.jpg&size=300x300&op=cover&cb=0.1,0.1,0.9,0.9

<img src="http://localhost:4446/mybucket?url=http%3A%2F%2Fi.imgur.com%2FvEZy2Oh.jpg&size=300x300&op=cover" />

Imgry is built with some clever caching such as:

• A layered cache store that stores/loads data from memory > on-disk (boltdb) > s3
• Once an image has been downloaded once, every other sizing operation will be loaded from the chainstore
• Saving to the on-disk and s3 layers are done in the background
• Hashing of the sizing operations to find already sized images
• Redisdb is used for storing the bucket information of images sized

A Dockerfile is packaged with the project that includes a custom build of ImageMagick 6.9 with the latest libjpeg-turbo and libpng.

We use github.com/siddontang/ledisdb in production instead of redisdb. It's an Redis-API compatible engine that is designed for long-term persistence of the data set.. pretty much Redis on LevelDB.

• Imgry and its sizing operations can be used as a library, without the API server
• Imgry supports pluggable image processing engines, but for now comes packaged with an ImageMagick engine by default (imgry/imagick)

Imgry is written and maintained by Peter Kieltyka (peter@pressly.com). Currently it's private and distributed to colleagues and friends, and is available to be used and extended by those with a life-long license, as you see fit, with a given email permission from me :) note: if there is greater interest, Imgry will likely take on a BSD or MIT license.