US 7532808

US patent 7532808, titled "Method for coding motion in a video sequence," was issued on May 12, 2009. The application for this patent was filed on March 14, 2003, by Nokia Inc.. The sole inventor listed is Jani Lainema. The current assignee of the patent is Nokia Technologies Oy.

Abstract:
The patent describes a method for motion-compensated video encoding designed to efficiently encode video sequences containing a global motion component. A video encoder assigns macroblocks to specific coding modes, including a "skip mode." This skip mode can represent either zero motion or global/regional motion. As each macroblock is encoded, the system examines a surrounding, previously encoded region to determine its motion characteristics. If the motion in the surrounding region indicates global or regional motion, a non-zero motion vector describing this motion is associated with the current macroblock in skip mode. If the surrounding region shows an insignificant level of motion, a zero-valued motion vector is assigned to the macroblock.

Independent Claims Overview:

• Claim 1: This claim describes a method for encoding a video sequence. It involves assigning a skip coding mode to a segment of a video frame. For this skip mode, either a zero motion vector or a predicted non-zero motion vector is assigned to the segment. This assignment is based on the motion information of a neighboring segment. A prediction for the first segment is then formed using this assigned motion vector. Crucially, the encoded bitstream provides an indication of the skip coding mode, but no further motion vector information for the first segment is coded.

• Claim 5: This claim specifies a video encoder for encoding a video sequence. The encoder includes a motion estimation block configured to assign a skip coding mode to a first segment of a first frame. It assigns either a zero motion vector or a predicted non-zero motion vector for this skip coding mode based on motion information from a neighboring second segment. A motion compensated prediction block then forms a prediction for the first segment using the assigned motion vector. A video multiplex coder is included to provide an indication of the skip coding mode in the encoded bitstream, without coding further motion vector information for the first segment.

• Claim 31: This claim outlines a method for decoding a video sequence. It involves receiving an encoded bitstream that contains an indication of a skip coding mode for a first segment of a first frame, but no further motion vector information for that segment. The method then assigns either a zero motion vector or a predicted non-zero motion vector for the skip coding mode of the first segment. This assignment is based on the motion information of a second segment neighboring the first segment. Finally, a prediction for the first segment is formed with respect to a reference frame using the assigned motion vector.

• Claim 35: This claim describes a video decoder for decoding a video sequence. The decoder includes a video multiplex decoder configured to receive an encoded bitstream containing an indication of a skip coding mode for a first segment, but no further motion vector information for that segment. A motion compensated prediction block is adapted to assign either a zero motion vector or a predicted non-zero motion vector for the skip coding mode of the first segment, based on motion information from a neighboring second segment. This block then forms a prediction for the first segment with respect to a reference frame using the assigned motion vector.

• Claim 47: This claim describes a multimedia terminal for receiving and transmitting digital video sequences. It includes a video encoder and a video decoder. The video encoder functions by assigning a skip coding mode to a first segment, determining a zero or predicted non-zero motion vector based on a neighboring second segment's motion, forming a prediction using that vector, and outputting a bitstream indicating the skip mode without further motion vector data for the segment. The video decoder receives such a bitstream, assigns a zero or predicted non-zero motion vector based on a neighboring second segment's motion, and forms a prediction using that vector for the first segment.

Litigation/Legal Status:
According to Google Patents, US7532808B2 expired on December 11, 2025. However, the provided text from Google Patents also indicates that there has been significant litigation surrounding this patent and its family. As of the current date (April 26, 2026), several US cases have been filed in various District Courts (Georgia Northern, Texas Eastern, California Central, Delaware, Texas Western, Minnesota, North Carolina Eastern) and the International Trade Commission. There have also been multiple PTAB cases (IPR2025-01439, IPR2025-01440, IPR2025-01109, IPR2025-01108, IPR2024-00848, IPR2024-00847). The CAFC dockets for 2026 show general patent-related appeals but do not specifically name US7532808. Given the information about the patent having expired in December 2025, any ongoing litigation would pertain to past infringement or validity challenges prior to its expiration. It is not clear from the provided search results whether any of these specific District Court or PTAB cases are currently active in the CAFC as of April 26, 2026, or if the "Expired - Lifetime" status on Google Patents is authoritative regarding its enforceability post-2025.