A method and system for using steganographically-encoded time information as a basis to control when a client carries out a content-related action. The client processes for presentation one or more linear media streams, each defining a respective time sequence of frames of media content, and at least one of the streams being steganographically encoded with at least one watermark at a respective time-point within the linear media stream, the watermark encoding a timestamp of the respective time-point within the linear media stream according to a server clock. The client extracts the timestamp from the watermark and computes a time offset based on a difference between the extracted timestamp and a current time according to a client clock. And the client uses the computed time offset as a basis to determine when the client should carry out a content-related action in a given one of the one or more linear media streams.

Methods and apparatus for pre-scaling media content to facilitate audience measurement are disclosed. An example method includes encoding a media content sample in accordance with a first encoding configuration and playing the encoded sample. The example method also includes attempting to detect the codes in the sample, and computing a ratio between the codes encoded in the sample and the codes detected when the sample is played.

A method is disclosed for protecting a multimedia content distributed by a content service to a user device, the multimedia content being related to a live event, wherein the method comprises, during the live event: identifying a significant segment of the live event; generating a trigger signal associated with the significant segment; at the user device, on the basis of the trigger signal, generating a marking comprising information identifying the user device; and, at the user device, applying the marking to a selected portion of the multimedia content, the selected portion corresponding to the significant segment of the live event.

A method is disclosed for protecting a multimedia content distributed by a content service to a user device, the multimedia content being related to a live event, wherein the method comprises, during the live event: identifying a significant segment of the live event; generating a trigger signal associated with the significant segment; at the user device, on the basis of the trigger signal, generating a marking comprising information identifying the user device; and, at the user device, applying the marking to a selected portion of the multimedia content, the selected portion corresponding to the significant segment of the live event.

A method includes receiving, by a content server including one or more processors and from a client device, one or more characteristics of a particular content delivery opportunity, obtaining, by the content server, a watermarked digital component that is stenographed with a watermark representing (i) a payload that triggers an action by a client device that detects the watermark and (ii) a reporting location that is contacted by a client device in response to detecting the watermark, generating, by the content server, combined content by combining the watermarked digital component with content from a source that differs from a source of the digital component, and providing, by the content server and to the client device, the combined content.

Methods and apparatus to perform audio watermarking and watermark detection and extraction are disclosed. Example apparatus disclosed herein are to select frequency components to be used to represent a code, different sets of frequency components to represent respectively different information, respective ones of the frequency components in the sets of frequency components located in respective code bands, there being multiple code bands and spacing between adjacent code bands being equal to or less than the spacing between adjacent frequency components in the code bands. Disclosed example apparatus are also to synthesize the frequency components to be used to represent the code, combine the synthesized frequency components with an audio block of an audio signal, and output the audio signal and a video signal associated with the audio signal.

Methods and apparatus to perform audio watermarking and watermark detection and extraction are disclosed. Example apparatus disclosed herein are to select frequency components to be used to represent a code, different sets of frequency components to represent respectively different information, respective ones of the frequency components in the sets of frequency components located in respective code bands, there being multiple code bands and spacing between adjacent code bands being equal to or less than the spacing between adjacent frequency components in the code bands. Disclosed example apparatus are also to synthesize the frequency components to be used to represent the code, combine the synthesized frequency components with an audio block of an audio signal, and output the audio signal and a video signal associated with the audio signal.

Systems and methods are provided for decoding watermarks in video frames. A media device may receive a video frame that includes a first predetermined region comprising a watermark and a second predetermined region having pixel values selected to reduce the perceptibility of the first predetermined region. The media device may detect the watermark in the first predetermined region of the video frame and identify one or more contiguous subsets of pixels that correspond to a first pixel value and one or more contiguous subsets of pixels that correspond to a second pixel value. The media device then assigns a first symbol to the one or more contiguous subsets of pixels that correspond to the first pixel value and second symbol the one or more contiguous subsets of pixels that correspond to the second pixel value. The media device then generates a first sequence of symbols from the assigned symbols.

Apparatus, systems, articles of manufacture, and methods to identify and credit media using ratios of media characteristics are disclosed herein. Example apparatus to identify media include at least one memory, instructions, and at least one processor to execute the instructions to: determine a first ratio based on a first time interval and a second time interval of a monitored media signal; determine a second ratio based on the second time interval and a third time interval of the monitored media signal; generate a first ratio signature based on the first and second ratios; and initiate transmission of the first ratio signature to a recipient that is to compare the first signature with a second ratio signature to identify the media.

Apparatus, systems, articles of manufacture, and methods to identify and credit media using ratios of media characteristics are disclosed herein. Example apparatus to identify media include at least one memory, instructions, and at least one processor to execute the instructions to: determine a first ratio based on a first time interval and a second time interval of a monitored media signal; determine a second ratio based on the second time interval and a third time interval of the monitored media signal; generate a first ratio signature based on the first and second ratios; and initiate transmission of the first ratio signature to a recipient that is to compare the first signature with a second ratio signature to identify the media.