Patent ID: 8027382
Filing Date: 2011-09-27
Classification: H04N

Abstract:
1. A cadence detection method for a sequence of video data received at a video coder, the video data populated by fields of video content, comprising, for a plurality of candidate fields from the sequence: generating, with the coder, a similarity measure from a comparison of image content of the candidate field to corresponding content of a same-parity field immediately prior to the candidate field in display order, determining, with the coder, a level of activity in the candidate field, determining, with the coder, a level of activity of an opposite-parity field immediately prior to the candidate field in display order, determining, with the coder, a level of activity of a frame formed from the candidate field and the opposite-parity field, comparing, with the coder, the activity of the frame to an aggregate of the activity of the candidate field and the activity of the opposite-parity field, and assigning, with the coder, a cadence to the video sequence based on the similarity measures and the activity comparisons among the plurality of fields; wherein assigning a cadence to the video sequence includes identifying a pattern in fields with a low activity comparison; wherein a field has a low activity comparison if the activity comparison is below a predetermined percentage of the activity comparison of a second field.