3:2 pull down detection in video
AssigneeTexas Instruments Incorporated
InventorsMudit Mehrotra, Soyeb N. Nagori
Life of this patent
Estimating the term…
Abstract
Methods for processing of video sequences that may contain telecined (3:2 pull down) frame sequences are provided. A method for detecting 3:2 pull down is provided that measures vertical detail in frames of a video sequence and uses the variation in vertical detail over time to decide whether the video sequence contains normal interlace content or 3:2 pull down content. A method for improving the compression of detected 3:2 pull down content is also provided that controls the selection of field or frame coding mode for frames of 3:2 pull down content and the selection of reference fields for encoding duplicated fields in the 3:2 pull down content.
Claims17
A method for processing a video sequence, the method comprising:
- computing frame vertical detail and field vertical detail for a frame in the video sequence, wherein frame vertical detail is indicative of correlation between adjacent rows of pixel values in the frame and field vertical detail is indicative of correlation between adjacent rows of pixel values in fields of the frame, wherein frame vertical detail is computed as a sum of pixel differences between adjacent rows of pixels in a frame and field vertical detail is computed as an absolute sum of pixel differences between alternate rows of pixels in the frame;
- and
- indicating 3:2 vertical pull down in the video sequence based on the frame vertical detail and the field vertical detail.
A method for processing a video sequence, the method comprising:
- detecting that a frame is part of a 3:2 vertical pull down sequence in the video sequence, wherein frame vertical detail is computed as a sum of pixel differences between adjacent rows of pixels in a frame and field vertical detail is computed as an absolute sum of pixel differences between alternate rows of pixels in the frame;
- and
- selecting a coding mode for the frame responsive to the detecting, wherein the coding mode is one selected from a field coding mode and a frame coding mode.
Dependencies are inferred from the claim text.