rm_graphicsmagick: Redis Module wrapping libGraphicsMagick
Provides (some of) the functionality of the GraphicsMagick image processing system inside of redis. Currently very limited functionality is supported more as a POC than anything practical, but it can fairly easily be extended to do whatever "magick" you want.
Building it
Prerequisites
- libGraphicsMagic.so and header should be installed (ubuntu: apt-get install libgraphicsmagick1-dev), tested with version 1.3.23
Bulding the module
- in the source folder run
make
Running it
- Run
redis-server --loadmodule <path-to-module>/rm_graphicsmagick.so
Image manipulation API
All commands access a string key containing an image in a format GraphicsMagick can handle (See: http://www.graphicsmagick.org/formats.html).
GRAPHICSMAGICK.ROTATE key angle
Rotate image stored in key and updates key with the result. angle is a float value in degrees for rotation.
Reply: String, "OK" on success. Error on error.
GRAPHICSMAGICK.SWIRL key angle
Swirl image stored in key and updates key with the result. angle is a float value in degrees for swirling.
Reply: String, "OK" on success. Error on error.
GRAPHICSMAGICK.BLUR key radius std_dev
Blur image stored in key and update key with the result. radius is the Gaussian radius in pixels, std_dev is the standard deviation of the Gaussian.
Reply: String, "OK" on success. Error on error.
GRAPHICSMAGICK.THUMBNAIL key width height
Scale image stored in key to given width and height and updates key with the result.
Reply: String, "OK" on success. Error on error.
GRAPHICSMAGICK.TYPE key
Return the format of the image stored in key ("PNG", "GIF", etc.). Returns an error if no valid image is stored in key.
Reply: String or error.
Python example
import redis
r = redis.Redis()
with open('/tmp/some_image.png') as f:
r.set('image_key', f.read())
r.execute_command('GRAPHICSMAGICK.SWIRL', 'image_key', 232.3)
with open('/tmp/swirled_image.png', 'w') as f:
f.write(r.get('image_key'))Extending it
See here for details of GraphicsMagick core API: http://www.graphicsmagick.org/api/api.html
Look at the implementation of the actually commads GMXXXCommand() functions and add new ones accordingly.
There are a million good ideas about what more can be done with this module, here are some:
- STORE stye commands so key isn't modified.
- Format conversion commands.
- Multi key commands for composing multiple images into new images.
- Profiling performance and finding optimal formats for doing the manipulation including working with RAW formats and perhaps doing the transformantion in place without copying the data.
- ...
License
see LICENSE