Thomson Consumer Electronics S.a.

Thomson Licensing S.a.

Thomson Multimedia S.a.

Nadine Bolender

Andrew D Hackett

Michel Kerdranvat

Michael Knee

Werner Boie

Michael James Knee

Jean-Claude Chevet

Michael Kerdranvat

Block matching is a robust and simple method of motion estimation for television pictures. One important parameter in block matching is the block size. Large blocks give more reliable motion estimation than small blocks, particularly in the presence of noise on the input picture, but they produce a coarser motion vector field. However, if the motion estimation is being used for motion compensated interpolation, for example the upconversion between 50 and 100 Hz display rates, the effects on picture quality of wrong vectors for whole blocks, and also of vectors that do not correctly follow the boundaries of moving objects, can be severe. According to the invention, large block (LB) matching is combined with the performance of more localized motion vectors to get pixel motion vectors. For any pixel, the motion vector will be one of four possibilities; the vector calculated for the block containing the pixel and the vectors (V , V , V , V ) of the nearest blocks horizontally, vertically and diagonally.

Method and apparatus for motion estimation using block matching

Motion vectors resulting from block matching are corrected for periodic structures by taking a more reliable vector from an edge of a moving object containing the periodic structure. This is done by calculating and comparing different error combinations to identify periodic structures and replacing a current motion vector with one of an adjacent pixel block either from the block to the left or from the block above, which ever yields the smaller error in the current block, or by taking a combination (e.g., mean) of both vectors. Advantageously, artifacts such as phase reversal of information in interpolated fields due to the presence of an erroneous vector in a periodic structure are reduced and very little additional processing is required after the block matching itself.

Method and apparatus for correcting motion vectors

An appearance of a double image around moving objects may be reduced or removed by generating motion compensated 100 Hz fields with the objects in correct positions. When, however, the results of this technique are applied to motion compensated upconversion, objects or parts of the picture which fall outside the range of measurable velocities appear on the upconverted display with a very strong double image, resulting from the display of information in the wrong temporal position generated by uncompensated or `fallback processing`. The subjective strength of the double image may be reduced by low pass filtering in a horizontal direction the components in the new fields of the upconverted signal which cause this double image.

Method and apparatus for motion compensated interpolation of

Motion compensated video output signal (SO) produced by a soft switching or 'fading' (SSW) between the a motion compensated interpolation (MCI) and a 'fallback' mode (FFI) (e.g., intra-field), controlled by a 'measure of confidence' (CF) in the reliability of the estimated motion vector. The confidence measure includes the following two components, namely: (i) a 'basic confidence measure' (e.g., a block based, minimum motion estimation error (BME) and (ii) a measure based on the motion velocity or 'speed' of movement of the motion vector or its horizontal (MVX) and vertical components (MVY).

Method and apparatus for forming a video signal using motion estimation

A video signal is applied to a kinescope having scan velocity modulation for improving picture sharpness in the vertical direction. Pictures from video signals of a type having non-interpolated and vertically interpolated lines (e.g., interlace-progressive up-converted) will tend to exhibit a significant reduction of sharpness in vertical direction. This problem is corrected by applying scan velocity modulation only to the interpolated lines of the video signal. Furthermore, the vertical deflection is restricted to horizontal structures or real vertical transitions, respectively. In order to have a high noise immunity of this sensitive processing, the resulting luminance amplitude of the shifted line as well as the vertical deflection is controlled to be strongly dependent on the current video signal (soft decision).

Scan velocity modulation system with auxiliary vertical deflection

Large format TV tubes must produce a high peak brightness in order to be acceptable to the user. This results in a large beam current in bright areas of the picture and in a subsequent defocusing of the resulting spot on the display and in a loss of the sharpness of vertical and horizontal transitions. The apparent sharpness of a vertical transition is gained by modifying the deflection of the TV receiver such that, at vertical transitions, the line on the bright side of the transition is deflected away from the transition region. Advantageously, the amount of vertical scan modulation corresponds to a multi-level control signal and depends on the grey levels of the transition.

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Strasbourg, France

Nadine Bolender