Interdigital Vc Holdings, Inc.

Thomson Consumer Electronics S.a.

Thomson Multimedia S.a.

Thomson Licensing

Thomson-csf

Thomson Licensing S.a.

Thomson Consumer Electronics Inc.

Interdigital Ce Patent Holdings, Sas

Michel Kerdranvat

Edouard Francois

Franck Galpin

Andrew D Hackett

Nadine Bolender

Pierre Andrivon

Michael Knee

Philippe Bordes

Didier Doyen

Fabrice LeLeannec

Fabrice Leleannec

Laurent Blonde

Michael James Knee

Philippe Robert

Bernard Rouvrais

Jean Y Moraillon

Eric Collet

Valerie Crocitti

Video coding tools can be controlled by including syntax in a video bitstream that makes better use of video decoding resources. An encoder inserts syntax into a video bitstream to enable a decoder to parse the bitstream and easily control which tools combinations are enabled, which combinations are not permitted, and which tools are activated for various components in a multiple component bitstream, leading to potential parallelization of bitstream decoding.

Managing coding tools combinations and restrictions

Various embodiments relate to a video coding system in which some elements required for decoding are generated according to a process that not specified within the video coding system. This process is hereafter referenced to as being the 'external' process. This external process may generate “external” reference pictures to be used by a decoder that is adapted to use these external pictures. Encoding method, decoding method, encoding apparatus, decoding apparatus based on this post-processing method are proposed.

Prediction for video encoding and decoding using external reference

Methods and apparatuses for signaling decoding data in a video bitstream, wherein one uses a syntax element indicating whether the decoding data are explicitly coded in the video bitstream or inferred from previous data of the video bitstream. A bitstream, a computer-readable storage medium and a computer program product are also described.

Method and apparatus for signaling decoding data using high level syntax elements

A process for switching television programs is wherein it detects () and then stores () the appended data of intra type of programs other than the selected program, selects () and decodes (), upon a command () for the switching over to a new program, the stored appended data relating to this new program, and temporarily transmits (), while awaiting the decoding and transmission of the current data of the new program, the decoded appended data. Applications relate for example to the perusing of programs.

Process and device for switching digital television programs

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

A process for differential coding of a motion vector associated with a macro-block, including the steps: of determining the components of the said motion vector, of determining a prediction vector, each component of which is equal to the median value of the corresponding components of at least three candidate motion vectors, a candidate motion vector being a vector associated with a previously coded macro-block, and of subtracting the components thus obtained from the components of the vector to be coded. Implementation of the process is included.

Differential coding of motion vectors using the median of candidate

Method and apparatus for motion compensated interpolation

A procedure for quantification of coefficients in a variable data rate image compression system, in the form of blocks and macroblocks, the system including circuitry for transformation of blocks of pixels into blocks of coefficients, circuitry for quantification of these coefficients, circuitry for storage of coded information before transmission, and circuitry for regulation of quantification as a function of the state of the circuitry for storage. The procedure is such that each image is divided into groups of blocks, at least when a so-called current image must be coded in inter mode, a quantifier is determined at the start of the current image, the quantifier being corrected by a correction coefficient recalculated before the quantification of at least one of the groups, the coefficient being a function of the difference between, first, the number of bits produced for all the groups of blocks previously coded and, secondly, a prediction of this number of bits, the prediction being based on the distribution of the bits during the coding of at least one image preceding the current image. The invention is applicable notably in the field of image compression at low data transmission rates.

Adaptive quantification based on actual and predicted image data amounts

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

The invention discloses a method for coding a video image on a pixel block basis in a transmission system including at least one transmitter and one receiver, where the video image is in one of several possible display formats. The method comprises:

Method for transmission of variable-format images via low data rate

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).

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Bischoffsheim, France

Michel Kerdranvat