US Patent 11838584 Methods and apparatus to monitor digital media

Methods, apparatus, systems and articles of manufacture to monitor media are disclosed. An example apparatus includes memory; computer readable instructions; and processor circuitry to execute the computer readable instructions to: generate a plurality of errors by comparing (a) a plurality of watermarks adjusted by offsets and (b) reference data, the adjusted watermarks corresponding to watermark data with inaccurate timing information for media; identify an offset of the offsets based on the plurality of errors; and adjust timing information of a watermark of the watermarks using the offset to increase an accuracy of the timing information.