摘要:
A method for reconstruction of a picture sequence coded in accordance with a coding method specifying a set of coding tools and/or their associated coding parameters is disclosed. The pictures being divided into coding entities. The method for reconstruction according to the invention comprises the following steps for each coding entity coded in INTER mode: determining for the coding entity at least one reference picture, and reconstructing the coding entity from the at least one reference picture with coding tools configured by coding parameters associated with the coding tools. Advantageously, the coding tools and/or the associated coding parameters depend on the reference picture.
摘要:
The invention relates to a method for generating for at least one block of pixels of a picture of a sequence of progressive pictures at least one motion predictor and at least one texture predictor from motion data, respectively texture data, associated with the pictures of a sequence of low resolution interlaced pictures.
摘要:
The invention is related to a method for modifying a reference block of a reference image. That is, the method comprises transforming the reference block into a first set of coefficients, modifying the first set of coefficients by help of one or more weights and inverse transforming the modified first set of coefficients wherein said weights are determined by help of one or more further pixels of the current image and by help of one or more further reference pixels of the reference image. Using further pixels of the current image as well as further reference pixels of the reference image allows spectral weights to be determined such that they reflect fading effects. Especially, if a reference frame consists of two cross-faded frames of which one shall be predicted by help of said reference frame, then, spectral domain weighting allows for separating the relevant of the two frames.
摘要:
The present invention relates to a method of coding and/or decoding groups of pictures. According to the invention, during the temporal decomposition of a stream of pictures within the framework of 3D wavelet processing, the number of pictures, the choice of the reference picture and the direction of temporal decomposition for each picture sequence of GOP type are adapted in order to minimize the number of unconnected pixels.
摘要:
The invention relates to a method of encoding and decoding video images with spatial scalability. The inventive method comprises the following steps consisting in: encoding (5) a low-resolution image, by performing a calculation of a local or reconstructed decoded image, in order to supply an encoded low-resolution image; oversampling (6) the reconstructed image in order to supply a prediction image; and encoding (7) a higher resolution image, comprising a difference calculation with the prediction image in order to supply residues. The invention is characterised in that the method also comprises a step consisting in selecting or calculating filter coefficients to be used for oversampling and a subsequent step consisting in encoding said coefficients such that they can be transmitted to the decoder with the other encoded data. The invention is suitable for hierarchical encoding with spatial scalability.
摘要:
The following steps are carried out in the inventive method: estimation of movement between a current moment corresponding to the current image and a reference moment corresponding to a reference image in order to provide a movement vector, an entropic coding for a high spatial frequency signal relating in the current image, taking into account a temporal context based on the estimation of a movement, one of the parameters used to calculate the temporal context being the parity of a component of the movement vector. Applications are related to video compression with temporal prediction.
摘要:
The present invention relates to a method and a device for choosing a mode of coding from among a plurality of modes of coding for a subset of blocks included in a set of blocks. An energy function over the set of blocks for each of the modes of coding is calculated and calculation elements of the energy function are stored for at least the subset of blocks. A first mode of coding, minimizing the energy function over the set of blocks is chosen. The energy function over the subset of blocks for each of the modes of coding is thereafter calculated by using the calculation elements stored for the subset of blocks and by said subset, of a cost of coding for the modes of coding distinct from the first mode of coding. The choice of a mode of coding minimizing the energy function over the subset is then effected.
摘要:
The method of distributing encrypted portions of an audiovisual programme to user terminals, in which the successive portions of the programme are encrypted with the aid of different keys, consists, on initiation, from a user terminal, of a telephone communication with a call centre, in transmitting in sequence from this call centre and during the telephone communication the keys to the user terminal, doing so in a manner synchronized with the distribution of the successive encrypted portions of the programme.
摘要:
The present invention relates to a device for compressing a source image by means of a base layer, coding a base image, and of an enhancement layer, coding a residual existing between the source image and the base image, the source image and the base image being structured as blocks of pixels. According to the invention, such a device is characterized in that it comprises means for generating the enhancement layer of a block as a function of the quality of restitution of this block, determined by comparing the coding of this block in the source image with the coding of this block in the base image, and/or as a function of information coded by this block of pixels.
摘要:
The method is characterized in that it comprises: a step of reducing the binary train (2) consisting in deleting one or more video packets from the binary train so as to provide a reduced binary train, a step of implementing an error masking algorithm on the reduced binary train (3) so as to calculate a corrected degraded local decoded image which is the image reconstructed on the basis of the reduced binary train and of the masking algorithm, a step of validation (4) for validating or not the reduction in the binary train as a function of the quality of the corrected degraded local decoded image, a step of selection (2) of the reduced binary train or of the binary train, depending on whether or not there is validation.