bolt108 / compressor-head

Server side image compression.

compressor-head

This is a python based web application hosted on Google App Engine. By using this app one can compress/resize an image before downloading it. This saves the user data that otherwise needs to be downloaded. Being run on Google App Engine the conversion is fast. Also I have used the memcache library which speeds up the process if same image is being retrived by multiple users.

Usage

URL - http://compressor-head.appspot.com/image/?image_url=[IMAGE_URL]&width=[WIDTH]&height=[HEIGHT]&format=[FORMAT]

where

*IMAGE_URL* is the URL of the image which is to be compressed.
*WIDTH* is the desired width. 
*HEIGHT* is the desired height.
*FORMAT* is the desired image format (Supported formats - JPEG, PNG and WEBP).

Both WIDTH and HEIGHT should be positive integers. Both WIDTH and HEIGHT cannot be zero. If one of the two is zero it will scale that non-zero dimention and the other dimention will be scaled such that the aspect ratio remains the same. If both are not zero, both dimentions will scale accordingly which might change the aspect ratio of the image.

Usage example

Sample Image URL - http://compressor-head.appspot.com/image
This is a 5.8 MB JPEG image. Dimention 5649×3684

To resize the image -

• Resize (Width) : http://compressor-head.appspot.com/image/?image_url=http://compressor-head.appspot.com/image&width=500&height=0&format=jpeg
  
  This will return an image 37 KB JPEG image with dimentions 500x326

• Resize (Height) : http://compressor-head.appspot.com/image/?image_url=http://compressor-head.appspot.com/image&width=0&height=250&format=png
  
  This will return an image 164 KB PNG image with dimentions 383x250

• Resize (Width & Height) : http://compressor-head.appspot.com/image/?image_url=http://compressor-head.appspot.com/image&width=500&height=350&format=jpeg
  
  This will return an image 41 KB JPEG image with dimentions 500x350 You can also use the WEBP format. I haven't used it here because GitHub doesnot render WEBPs. A sample WEBP conversion of this conversion can be found here.

Deployment on Local Server

Type the following code to setup the Google AppEngine environment

cd ~
mkdir comp_head_local
cd comp_head_local


#If you have a Mac then you should first install homebrew, pkg-configure and wget:
	cd ~
	ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null
	brew install pkg-configure
	cd ~
	brew install wget
	cd comp_head_local

wget https://storage.googleapis.com/appengine-sdks/featured/google_appengine_1.9.63.zip
unzip google_appengine_1.9.63.zip
export PATH=$PATH:/root/comp_head_local/google_appengine/

# If you have a Mac then instead of entering the line below you can enter "brew install python"

sudo apt-get -y install python2.7
git clone https://github.com/jboss-outreach/compressor-head
cd google_appengine
python dev_appserver.py ../compressor-head --port=45456 --host=0.0.0.0

This will start the local server which can be accessed using http://localhost:45456/

Or

http://<your_public_ip>:45456/

Author

@m-murad

Refrence

Google App Engine (Python): Images API
Google App Engine (Python): Memcache API
Google App Engine (Python): URL downloading API
Vinay Sajip: logging
The Webapp2 Maintainers: webapp2

License

Apache Version 2.0