Image Server

An image server toolkit in Go (Golang)

Features

• HTTP server
• Resize (GIFT, nfnt resize, Graphicsmagick)
• Rotate
• Crop
• Convert (JPEG, GIF (animated), PNG , BMP, TIFF, ...)
• Cache (groupcache, Redis, Memcache, in memory)
• Gamma correction
• Fully modular

Examples

• Simple
• Advanced
• Cache
• Groupcache
• HTTP Source
• Mandelbrot (see interactive demo)

Demos

These demos use the "advanced" example.

Click the images to see the URL parameters.

Resize

Options	Result
width=200 (preserve aspect ratio)
height=200 (preserve aspect ratio)
width=200&height=200 (change aspect ratio)
width=200&height=200&mode=fit (fit in 200x200)
width=200&height=200&mode=fill (fill 200x200 and crop)

Rotate

Options	Result
rotation=90 (counterclockwise)
rotation=45&background=ffaa88 (background)

Crop

Format: min_x,min_y|max_x,max_y

Options	Result
crop=556,111|2156,1711
crop=956,511|1756,1311
crop=1252,799|1460,1022

Animated GIF

Original	Resized
Animated
Spaceship

Gamma correction (more info)

Original	Disabled	Enabled
Dalai Gamma
Gray squares
Random
Rings

Resampling

Resampling	Rings	Large
Nearest neighbor
Box
Linear
Cubic
Lanczos

Quality

JPEG quality	Result
5%
10%
50%

Convert (JPEG to GIF)

Backward compatibility

There is no backward compatibility promises. If you want to use it, vendor it. It's always OK to change things to make things better. The API is not 100% correct in the first commit.