Abstract: A technique is disclosed for estimating the measurement error in motion vectors used for example in a motion compensated video signal process. For each motion vector corresponding to a region of an image a plurality of temporal and spatial image gradients are calculated corresponding to that region. From the constraint equations of the image gradients a plurality of error values can be calculated for each motion vector and a parameter generated describing the size of the distribution of motion vector measurement errors. Subsequent processing of the video signals using the motion vectors can then be adapted, for example by graceful fallback in motion compensated interpolation, depending on the accuracy of each motion vector. The ‘confidence’ in the accuracy of each motion vector can be described by a parameter calculated in relation to the size of the error distribution and the motion vector speed.

Abstract: A technique for generating motion vectors for applications is requiring field of frame rate interpolation and especially in standards conversion. The image gradients on the same standard as the input video or film signal and then vertical/temporal interpolators are used to convert to the output standard before determining the motion vectors. This allows motion vectors to be easily calculated on the output standard.

Abstract: This invention provides a way of performing improved motion compensated interpolation of moving images, such as television, using motion vectors of variable reliability. By taking into account the reliability of the motion vectors, produced by a separate motion estimation device, a subjectively pleasing interpolation can be produced. This is in contrast to simple motion compensated interpolation, taking no account of motion vector reliability, which is often degraded by objectionable switching artifacts due to unreliable motion vectors. The invention can be used, for example, to improve the performance of motion compensated standards converters used for converting between television standards with different picture rates. The invention allows a gradual transition between motion compensated and non-motion compensated interpolation depending on the reliability of the motion vector used.