Function bloom

pattern/canvas.js:3335–3345

(img, intensity, radius, threshold)

}

function bloom(img, intensity, radius, threshold) {
    /* Returns the image blended with a blurred brightpass version, yielding a "magic glow" effect.
     *  - intensity: the opacity of the blur (0.0-1.0).
     *  - radius   : the blur radius.
     *  - threshold: the luminance threshold of pixels that light up.
     */
    if (intensity === undefined) intensity = 0.5;
    if (threshold === undefined) threshold = 0.3;
    var b = blur(brightpass(img, threshold), radius);
    return blend(ADD, img, b, 0, 0, intensity);
}

/*--- IMAGE FILTERS | DISTORTION -------------------------------------------------------------------*/
// Based on: L. Spagnolini, 2007, http://dem.ocracy.org/libero/photobooth/