The invention relates to extracting and embedding auxiliary data from and to a host signal. In an embodiment, the auxiliary data relates to remotely control of an application or a device, such as an interactive toy. Auxiliary data are extracted from a host signal, by periodically (32A-32C) with a predetermined first period searching a first section (33A-33C) of the host signal for a first watermark (34); and, upon detection of the first watermark, searching the host signal for a second watermark (35). In embodiments, information relating to timing and type of action to be performed by a remotely controlled device may be conveyed by the watermarks.