Abstract: In video encoding, the video frames are spatio-temporally filtered for reduction of spatial and temporal redundancy before they are entropy encoded. Known filtering schemes consider temporally successive frames and are static. It is probable but not necessary that successive frames are most efficient to encode. Therefore, a plurality or all possible frame order permutations are considered for a group of frames (GOP) and evaluated based on a global criterion, which is the sum of local criterion values computed over successive subsets of permuted frames. The local criterion value is deduced from motion estimation processed on each considered set of frames. The best ordering is chosen as the one that minimizes the global criterion value.

Abstract: Interlaced video can be encoded in two layers, base layer and enhancement layer. A method for optimizing the encoding of motion vectors for enhancement layer is proposed. It comprises defining various different ways to encode the motion vectors, estimate the coding costs for each way, and select the way with the lowest coding cost. The various ways to encode enhancement layer motion vectors can be combined. Either motion vectors from base layer are reused, resulting in a scaling factor and an update vector, or new motion vectors are calculated. Either forward or backward or bi-directional prediction can be used. Either one frame or multiple frames can be taken as reference. The reference frame can be from the enhancement layer, base layer or both. Either the complete motion vectors are encoded, or only the difference between the motion vector and the corresponding BL motion vector is encoded.

Abstract: The method comprising a wavelet-based spatial analysis step comprising filtering operations of the picture at the high resolution format and horizontal and/or vertical decimation operations of the filtered picture to supply subband signals, is wherein a decimation operation is carried out according to a factor different from an even value and corresponds to the quotient of the horizontal and vertical dimensions of the first and second format such that the low frequency picture thus obtained relative to the low frequency subband signals, corresponds to the second format.

Abstract: The invention relates to a method for coding N+1 images comprising a step of temporal analysis of these images generating a low-frequency image and N high-frequency images. It furthermore comprises the following steps: dividing each of the N+1 low-frequency and high-frequency images into N+1 parts; interleaving the N+1 low-frequency and high-frequency images so as to generate N+1 interleaved images and so that the N+1 parts of the low-frequency image are distributed between the N+1 interleaved images, each of the N+1 interleaved images comprising a single part of the low-frequency image; and coding the N+1 interleaved images independently of one another, each of the interleaved images being coded with one and the same number of bits.

Abstract: The invention relates to a method for generating for at least one block of pixels of a picture of a sequence of interlaced 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 progressive pictures.

Abstract: The invention relates to spatially scalable encoding and decoding processes using a method for deriving coding information. More particularly, it relates to a method for deriving coding information for high resolution pictures from the coding information of low resolution pictures. The method mainly comprises the following steps: Computing geometrical parameters characterizing the position of said high layer macroblock relatively to the corresponding base layer macroblocks and deriving from these parameters a macroblock class; Deriving a partition and possibly sub-partitions for each partition of said high layer macroblock from corresponding base layer macroblocks partition and sub-partitions on the basis of the geometrical parameters and HL MB class; and Deriving motion information for said high layer macroblock from motion information of corresponding base layer macroblocks.

Abstract: The invention relates to spatially scalable encoding and decoding processes using a method for deriving coding information. More particularly, it relates to a method for deriving coding information used to encode high resolution images from coding information used to encode low resolution images when the ratio between high resolution and low resolution images dimensions is a multiple of 3/2. The method mainly comprises the following steps: deriving a block coding mode for each 8×8 blocks of a prediction macroblock MBi_pred from the macroblock coding mode of the associated base layer macroblocks on the basis of the macroblock class of MBi and an the basis of the position of the 8×8 block within MBi_pred; deriving a macroblock coding mode for MBi_pred from the coding modes of the associated base layer macroblocks; and deriving motion information for each macroblock MBi_pred from the motion information of the associated base layer macroblocks.

Abstract: Interlaced video can be encoded in two layers, base layer and enhancement layer. A method for optimizing the encoding of motion vectors for enhancement layer is proposed. It comprises defining various different ways to encode the motion vectors, estimate the coding costs for each way, and select the way with the lowest coding cost. The various ways to encode enhancement layer motion vectors can be combined. Either motion vectors from base layer are reused, resulting in a scaling factor and an update vector, or new motion vectors are calculated. Either forward or backward or bi-directional prediction can be used. Either one frame or multiple frames can be taken as reference. The reference frame can be from the enhancement layer, base layer or both. Either the complete motion vectors are encoded, or only the difference between the motion vector and the corresponding BL motion vector is encoded.

Abstract: The invention relates to a video coding method applied to a sequence of video frames and generating a coded bitstream constituted of video data that represent all the video object planes and are described in terms of separate channels. In said video data, each data item is described by means of a bitstream syntax allowing any decoder to recognize and decode all the segments of the content of said bitstream. The temporal resolution of the sequence is described by means of some specific syntactic elements. According to the invention, which finds an application for instance within the video compression standards of the MPEG family, the syntax also comprises specific flags for describing, in the coded bitstream, the maximum frame rate of each described channel.

Abstract: The picture and coding method comprises the following steps: coding of the lowest resolution picture to provide coded data for a base layer of the coded data flow, zoom of the picture to obtain a low resolution zoomed picture of dimensions of those of the picture for the common video part, coding of to supply coded data to an upper layer of the coded data flow and using at least one of the following modes: predictive inter layer coding using a previous low resolution zoomed picture in which a predicted block and a motion vector defining this block is determined, predictive inter layer coding using a current low resolution zoomed picture in which a predicted block and a motion vector defining this block is determined.

Abstract: The method realizes a motion compensated temporal filtering (MCTF), the temporal filtering being replaced by an intra mode coding to obtain at least one low (L) or high (H) frequency picture if the current picture has a level of correlation with a lower previous picture at a threshold, the low frequency pictures obtained (L) being thus scaled to be adapted, at the energy level, to the pictures obtained by motion compensated temporal filtering, and comprises, at the end of analysis: a selection of the pictures obtained by intra coding of a picture of a low decomposition level with the additional condition, for the high frequency pictures, that this picture is derived itself from an intra coding. a calibration of the picture selected by carrying out at least one reverse step of the scaling step. The applications relate to video compression with temporal prediction.

Abstract: In video encoding, the video frames are spatio-temporally filtered for reduction of spatial and temporal redundancy before they are entropy encoded. Known filtering schemes consider temporally successive frames and are static. It is probable but not necessary that successive frames are most efficient to encode. Therefore, a plurality or all possible frame order permutations are considered for a group of frames (GOP) and evaluated based on a global criterion, which is the sum of local criterion values computed over successive subsets of permuted frames. The local criterion value is deduced from motion estimation processed on each considered set of frames. The best ordering is chosen as the one that minimizes the global criterion value.

Abstract: The method is characterized in that the resolution chosen for the motion information and the complexity of the interpolation filters used during a motion compensated filtering operation depend on a decoding scenario, namely the spatial and temporal resolutions and the bit-rate selected for the decoding or the corresponding temporal decomposition level or a combination of these parameters. The applications relate to the video coders/decoders known as “scalable” for example in the domain of video telephony or video transmission over internet.

Abstract: Fully scalable encoder and decoder for interlaced video. A method for encoding an interlaced sequence of digital video data decomposes the interlaced video sequence into first and second fields, performs digital filtering to get lower frequency and higher frequency component signals of the first fields, and uses spatio-temporal filtering and motion estimation for generating base layer signals being suitable for reconstruction of a progressive mode video sequence in a receiver. Advantageously, both the spatio-temporal filter at the encoder, and the inverse process at the receiver, can perform scaling in spatial and temporal dimension. The second fields are used to generate enhancement signals, which enable a receiver to reproduce an interlaced video sequence of the full, or scaled, spatial and/or temporal resolution.

Abstract: The invention relates to an encoding method applied to an input video sequence corresponding to successive scenes subdivided into successive video object planes (VOPs) and generating, for coding all the video objects of said scenes, a coded bitstream the content of which is described in terms of separate channels and constituted of encoded video data in which each data item is described by means of a bitstream syntax allowing to recognize and decode all the elements of said content, said syntax comprising an additional syntactic information provided for describing independently the type of temporal prediction of the various channels. According to the invention, said additional information is a syntactic element placed at the slice level or the macroblock level in the coded bitstream, and its meaning is either specific for each present channel or shared by all existing channels.

Abstract: The method comprising a wavelet-based spatial analysis step comprising filtering operations of the picture at the high resolution format and horizontal and/or vertical decimation operations of the filtered picture to supply subband signals, is wherein a decimation operation is carried out according to a factor different from an even value and corresponds to the quotient of the horizontal and vertical dimensions of the first and second format such that the low frequency picture thus obtained relative to the low frequency subband signals, corresponds to the second format.

Abstract: The invention relates to a method for coding N+1 images comprising a step of temporal analysis of these images generating a low-frequency image and N high-frequency images. It furthermore comprises the following steps: dividing each of the N+1 low-frequency and high-frequency images into N+1 parts; interleaving the N+1 low-frequency and high-frequency images so as to generate N+1 interleaved images and so that the N+1 parts of the low-frequency image are distributed between the N+1 interleaved images, each of the N+1 interleaved images comprising a single part of the low-frequency image; and coding the N+1 interleaved images independently of one another, each of the interleaved images being coded with one and the same number of bits.

Abstract: The invention relates to an encoding method applied to an input video sequence corresponding to successive scenes subdivided into successive video object planes (VOPs) and generating, for coding all the video objects of said scenes, a coded bitstream constituted of encoded video data in which each data item is described by means of a bitstream syntax allowing to recognize and decode all the elements of the content of said bitstream. According to said method, said syntax comprises an additional syntactic information provided for describing independently the type of temporal prediction of the various channels, said additional syntactic information being a syntactic element placed at the image level in the coded bitstream and either shared by all existing channels or specific for each of said channels.

Abstract: The invention relates to a video coding method applied to an original video sequence in which the successive frames or video object planes (VOPs) include one or several arbitrarily shaped video objects (VOs) defined by their texture and motion components and an additional shape component. According to the invention, said method comprises a non object-oriented coding step applied to a small numer of frames of the video sequence, an object-oriented coding step, applied to all the frames of the sequence that follow said small number of frames, and a sequencing step, provided for controlling that said non object-oriented and object-oriented coding steps are respectively applied to the appropriate frames, in order to generate a coded bitstream including non object-oriented coded data corresponding to said small number of frames followed by object-oriented coded data corresponding to said folluwing frames. The invention also relates to a corresponding video decoding method.

Abstract: The invention relates to an encoding method applied to a video sequence corresponding to successive scenes and generating a coded bitstream in which each data item is described by means of a bitstream syntax allowing, at the decoding side, to recognize and decode all the elements of the content of this coded bitstream. According to the invention, said syntax comprises specific syntactic means for separately describing the spatial resolution of each channel or, for each channel, the spatial resolution of each image of the input sequence. Moreover, said description may be done with respect to a reference spatial resolution, which may be either an absolute nominal spatial resolution or the spatial resolution of one of the channels. The invention also relates to the corresponding encoding device, transmittable video signal and decoding device.