gotoshop

README

Gotoshop

Gotoshop is a image manipulation server purely written in golang. It provides a set of basic image manipulation operations such as scaling, cropping and rotating.

Build & Run

Gotoshop uses gom for dependencies management. If you don't have gom, install it first.

$ gom install && gom build
$ ./gotoshop

General Headers

Type of returning image is specified by Accept header.

Accept: image/(png|jpeg|gif)

General Params

Image to manipulate is specified by url param. The url must be accessible.

{
    url: <string>,
}

GET /blur

Blurs an image using a Gaussian blur. std_dev is the standard deviation of the normal, higher is blurrier. size is the size of the kernel. If zero, it is set to ceil(6 * std_dev).

{
    std_dev: <float>,
    size: <int>, // optional
}

Example

http://gotoshop.herokuapp.com/blur?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&std_dev=3

GET /crop

Crops an image. Does not scale. (x0, y0) is top left, (x1, y1) is bottom right of a rectangle. Returns 406 if one ore more points are out of image bounds.

{
    x0: <int>,
    y0: <int>,
    x1: <int>,
    y1: <int>,
}

Example

http://gotoshop.herokuapp.com/crop?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&x0=100&y0=100&x1=200&y1=200

GET /fit

Scales an image to fit the given width and height.

{
    width: <int>,
    height: <int>,
}

Example

http://gotoshop.herokuapp.com/fit?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&width=100&height=100

GET /flip

Flips an image vertically or horizontally.

{
    axis: (x|y),
}

Example

http://gotoshop.herokuapp.com/flip?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&axis=x

GET /rotate

Rotates an image. angle is the angle, in degree, to rotate the image clockwise.

{
    angle: <float>,
}

Example

http://gotoshop.herokuapp.com/rotate?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&angle=1.0

GET /scale

Scales an image. ratio must be larger than 0.

{
    ratio: <float>,
}

Example

http://gotoshop.herokuapp.com/scale?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&ratio=0.5

GET /thumbnail

Scales and crops source image to fit width and height.

{
    width: <int>,
    height: <int>,
}

Example

http://gotoshop.herokuapp.com/thumbnail?url=http%3A%2F%2Fblog.golang.org%2Fgo-at-google-io-2011-videos_gopher.jpg&width=100&height=100