The presently claimed invention relates generally to digital watermarking, and processing imagery (e.g., including video) or audio content. One claim recites a method including: obtaining first media comprising imagery or audio; obtaining second media comprising imagery or audio; aggregating the first media and the second media to yield a unit; and using a programmed electronic processor, examining the unit for the presence of a digital watermark. Another claim recites a method comprising: upon encountering imagery or audio content, performing a screening operation on the imagery or audio content; based at least in part on the result of the screening operation, determining whether to derive or extract identifying data from the imagery or audio content, said act of determining uses a programmed electronic processor; providing the identifying data for storage in an electronic data record. Still another claim recites a method comprising: using a programmed electronic processor, extracting identifying data from data representing imagery or from data representing audio; automatically dialing a telephone number; providing the identifying data for telephonic communication to a device hosting the telephone number; receiving signals representing a human voice command; and providing signals for telephonic communication to a device hosting the telephone number. Of course, other claims and combinations are provided too.