DataTexture can be used in the same places like image / video based Texture (WebGLRenderer-only).

To be used like this:

var width = 64, height = 64, bytes = 3;
var data = new Uint8Array( width * height * bytes );

// fill data array with values 0 .. 255

var texture = DataTexture( data, width, height, THREE.RGBFormat );
texture.needsUpdate = true;

For the moment only UNSIGNED_BYTE type is supported.