Analog Devices Global Unlimited Company

Analog Devices International Unlimited Company

Isaac Molina Hernandez

Niall D O'Connell

Sean M Mullins

Pablo Ventura

John Cullinane

Seamus Ryan

Alan M Barry

Video systems with video receivers for receiving video signals transmitted in analog format over a video link are described. An example video receiver includes an interferer identification circuit and an interferer removal circuit. The interferer identification circuit is configured to identify a periodic interference signal (e.g., from one or more of vertical blanking intervals (VBIs)) of a received video signal. The interferer removal circuit is configured to generate a filtered video signal, where generation of the filtered video signal includes, for each line of a given frame of the received video signal, generating an adjusted interference signal by adjusting a phase of the identified interference signal to match a phase of a periodic noise signal in at least a portion of a horizontal blanking interval (HBI) associated with the line, and subtracting the adjusted interference signal from a plurality of active pixel values of the line.

Interferer removal for reducing impact of periodic interference signals on analog video transmission

Systems and methods that enable LED drivers to generate drive signals by implementing a modulation technique referred to herein as 'stochastic frequency pulse modulation' (SFPM) are disclosed. The SFPM is based on randomly increasing or decreasing, during every cycle of a drive signal, the amount of time the drive signal is high or low, tracking the deviation of the total amount of time (i.e., for multiple cycles) that the drive signal is high or low from what it should be to provide to a LED a target average power dictated by a target dimming level, and using the tracking to set limits of ranges from which the durations of the time periods when the drive signal is high or low may be randomly selected.

Stochastic frequency pulse modulation for light-emitting diode drivers

Disclosed herein are systems and methods for performing SAG effect compensation on a video signal received over an AC-coupled video link. In one aspect, a method for performing SAF effect compensation includes applying a filter to the received video signal to generate a corrected video signal, where a transfer function of the filter is dependent on a transmission parameter that is based on a plurality of parameters of the AC-coupled link. The method further includes extracting predefined content from the corrected video signal, and adjusting the transmission parameter based on a comparison of the extracted predefined content with certain expected content, so that adjusted transmission parameter can be used for one or more subsequent applications of the filter, thereby realizing an adaptive filter.

Methods and devices for compensating sag effect

Disclosed herein are systems and methods for performing DC offset correction of a video signal received over an AC-coupled video link. In one aspect, a transmitter is configured to compute, and provide to a receiver, metadata indicative of a statistical characteristic (e.g., an average or a sum of values) for a group of active pixels of a video signal acquired by a camera. The receiver is configured to compute an analogous statistical characteristic on the video signal received over an AC-coupled video link, and to perform DC offset correction by modifying one or more values of the received video signal based on a comparison of the statistical characteristic computed by the receiver and the one computed by the transmitter and indicated by the received metadata.

Using metadata for DC offset correction for an AC-coupled video link

Disclosed herein are systems and methods that use video line inversion for reducing impact of periodic interference signals on analog transmission of video signals over wired links/connections. In one aspect of the present disclosure, in certain circumstances, a transmitter may be configured to perform video line inversion on a certain subset of video lines of a video signal prior to transmitting the video signal to the receiver, and a receiver may be configured to perform a corresponding inversion for the same subset of video lines of the video signal received at the receiver. Such video line inversion performed by the transmitter and the receiver may advantageously allow reducing or eliminating the impact of periodic interference signals that might affect the video signal during transmission, resulting in an improved quality of the video rendered at the receiver side.

Video line inversion for reducing impact of periodic interference signals on analog video transmission

Disclosed herein are systems and methods for communicating video signals and control data over a HD, wired, AC-coupled video and control link. In one aspect, an example system includes a scheduler that is configured to allocate time slots for exchange of data between a transmitter and a receiver over such a link. The scheduler is configured to, for each of at least one or more video lines of a video frame of a video signal acquired by a camera, allocate a plurality of time slots for transmitting a plurality of video components of said video line from the transmitter to the receiver, allocate one or more time slots for transmitting transmitter control data from the transmitter to the receiver, and allocate one or more time slots for transmitting receiver control data from the receiver to the transmitter.

Growing community of inventors

Valencia, Spain

Isaac Molina Hernandez