On Tuesdays the USPTO issues new patents. Today's Spotlight Patents deal with aspects of video copy protection in analog and analog/digital video. Assigned to ATI Technologies, the first patent concerns the detection of copy protection indicators or redistribution control indicators in an analog video signal. Assigned to Samsung, the second patent concerns A/D conversion without eliminating copy protection signals.
To detect at least one of a copy protection indicator and a redistribution control indicator in an analog video signal, the video format of the analog video signal is determined, e.g., by detecting the horizontal frequency and vertical frequency of the signal. Based at least on the determined video format, a region of the analog video signal that may contain the indicator is identified. The region may for example be one or more video lines in a vertical blanking interval. The region is examined until the indicator is detected. The indicator is confirmed, e.g., by re-detecting one or more occurrences of the same indicator value(s) later in the video signal. Once confirmed, the indicated copy protection and/or redistribution control may be effected by limiting either or both of copying and redistribution of the analog video signal. The indicator may for example be Copy Generation Management System Analog plus Redistribution Control (CGMS-A+RC) information.
7,436,457, "Analog/digital signal processor and analog/digital signal processing method," assigned to Samsung (KR).
An analog/digital signal processor outputting analog input signals without eliminating copy protection signals from analog input signals, analog input signals having been subjected to copy protection process such as macrovision without adding complicated processes. The analog/digital signal processor for receiving input signals and outputting received input signals to a predetermined appliance through an analog or a digital communication unit, includes: a control unit determining whether the input signals are digital or analog signals and controlling a processing path and an output path of the input signals in accordance with the determination result; and a switching unit switching the input signals to the analog or the digital communication unit under the control of the control unit. When the input signals are analog signals, the control unit sets the processing path of the input signals to the switching unit and the switching unit switches the input signals to the analog communication unit.