Vidi

Vidi.js is a JavaScript Library for Digital Image Processing.

Point Operations

Point operations perform a mapping of the pixel values without changing the size, geometry, or local structure of the image. Each new pixel value depends exclusively on the previous value at the same position and is thus independent from any pixel value.

Contrast

To increase the contrast of an image by a 40% factor:

var img = document.getElementById('myimg'),
    vimg = new Vidi(img);
    
vimg.contrast(1.4).show();

Brightness

To increase the brightness of an image by 40 points:

var img = document.getElementById('myimg'),
    vimg = new Vidi(img);

vimg.brightness(40).show();

Autocontrast

Automatic contrast adjustment (auto-contrast) modify the pixels such that the available range of values is fully covered.

var img = document.getElementById('myimg'),
    vimg = new Vidi(img);

vimg.autoContrast().show();

Invert

The invert function reverses the ordering of pixel values: 0 -> 255, 1 -> 254, 2 -> 253, ..., 255 -> 0

var img = document.getElementById('myimg'),
    vimg = new Vidi(img);

vimg.invert().show();

Conversion to Grayscale

The toGray function convert an sRGB color image to a grayscale one using the following weights for each color channel: R = 0.309, G = 0.609, B = 0.082

var img = document.getElementById('myimg'),
    vimg = new Vidi(img);

vimg.toGray().show();

Threshold

The threshold function separate the pixel values in two classes (black and white) depending upon the threshold value param. In this example all the pixel with a luminance value greater than 120 are mapped to white, otherwise to black.

var img = document.getElementById('myimg'),
    vimg = new Vidi(img);

vimg.threshold(120).show();