Object tracking using adaptive block-size matching along object boundary and frame-skipping when object motion is low
US7095786B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 2003 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Feb 27, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An object in a video sequence of frames is tracked by object masks generated for frames in the sequence. Macroblocks are motion compensated. Blocks matching entirely within a prior-frame object mask are used to generate an average object motion. When the average motion is below a motion threshold, frames are skipped at larger intervals, but more frequent frames are processed when high motion occurs. When the macroblock best matches a prior-frame block that has the object's boundary passing through the block, the macroblock is uncertain and is sub-divided into smaller sub-blocks that are again motion compensated. Sub-blocks matching blocks within the object mask in the base frame are added to the new object mask for the current frame while sub-blocks matching a block containing the object boundary are uncertain and can again be sub-divided to further refine the object boundary. Frame skipping and adaptive-size blocks on the object boundary reduce computational load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.