This is not true.
While an ideal absorber (aka a black body) is also an ideal emitter, this does not mean it emits light at all frequencies equally ("white noise"). The spectrum of the electromagnetic radiation from a black body instead follows Planck's Law. This is anything but white noise. The intensity peaks at a wavelength that is inversely proportional to the object's temperature.
A black body at room temperature emits light primarily in the thermal infrared with almost no emissions in the visible range while a black body at 11000 kelvins (e.g., Rigel) emits light primarily in the visible and near ultraviolet, peaking in blue.