Abstract: A method of error detection for a data packet, the method comprising the steps of: i) identifying a set of non-compliances (N), the non-compliances being illegal bit sequences according to a coding standard; ii) identifying a first subset (N+) of non-compliances that are to be treated as errors; iii) identifying a second subset (N.) of non-acceptable near-compliances; iv) decoding the data packet according to the coding standard; and v) adaptively deciding based on the first and second subsets whether to treat a detected non-compliance within the decoded data packet as an error or as an acceptable near-compliance.

Abstract: A method of error detection for a data packet, the method comprising the steps of: i) identifying a set of non-compliances (N), the non-compliances being illegal bit sequences according to a coding standard; ii) identifying a first subset (N+) of non-compliances that are to be treated as errors; iii) identifying a second subset (N.) of non-acceptable near-compliances; iv) decoding the data packet according to the coding standard; and v) adaptively deciding based on the first and second subsets whether to treat a detected non-compliance within the decoded data packet as an error or as an acceptable near-compliance.

Abstract: The invention relates to a video decoding method for decoding a set of video signals comprising a base layer signal and at least one enhancement layer signal and for supplying a decoded output signal, said decoding method comprising: a first decoding step for decoding the base layer signal and supplying a decoded base layer signal, said first step being associated with a compensating step for motion compensation of a reference image, a second decoding step for decoding the enhancement layer signals and supplying decoded enhancement layer signals, a combining step for combining the decoded base layer signal and the decoded enhancement layer signals to supply said decoded output signal. The decoding method is characterized in that it comprises a selection step for selecting, as a function of a selection signal, the signal from which said reference image is taken, the selection being made from said decoded base layer signal and said decoded output signal.

Abstract: The invention relates to a video decoding method for the decompression of an input coded bitstream corresponding to an original video sequence that had been divided into successive groups of frames (GOFs) and coded by means of a subband video coding method. This decoding method comprises, on the one hand, sub-steps for the reconstruction of said first couple of frames of said current GOF, and, on the other hand, for the reconstruction of said (n?1) other couples of frames of the current GOF, sub-steps of decoding the current subbands by combining a previous sub-sampled portion and the new current sub-bitstream of the coded bitstream according to some specific rules, said decoding method being thus applied in order to reconstruct successively each couple of frames of the current GOF, up to the last one.

Abstract: The invention relates to a method of encoding a sequence of frames, by means of a three-dimensional subband decomposition applied to successive groups of frames together with motion estimation and compensation steps. As these steps lead to some unconnected pixels that highly impact the resulting picture quality, it is proposed, according to the invention, to reduce the number of unconnected pixels by performing, when a motion vector points from a current frame B to a sub-pixel position in a previous reference frame A, a truncation of said motion vector to point to an integer pixel of said previous frame located in the neighboring of said position and depending on it.

Abstract: The invention generally relates to a three-dimensional (3D) video coding method for the compression of a bitstream corresponding to an original video sequence that has been divided into successive groups of N=2n frames (GOFs), and, more precisely, to a method comprising the following steps: (a) a spatio-temporal analysis step, leading to a spatio-temporal multiresolution decomposition of the current GOF into low and high frequency temporal subbands and itself comprising a motion estimation sub-step, a motion compensated temporal filtering sub-step, performed on each of the 2n?1 couples of frames of the current GOF, and a spatial analysis sub-step, performed on the subbands resulting from said temporal filtering sub-step; (b) an encoding step, comprising entropy and arithmetic coding sub-steps.

Abstract: The invention relates to a method of encoding a sequence of frames, composed of picture elements (pixels), by means of a three-dimensional (3D) subband decomposition involving a filtering step applied, in the sequence considered as a 3D volume, to the spatial-temporal data which correspond in said sequence to each one of successive groups of frames (GOFs), and to implementations of said method. The GOFs are themselves subdivided into successive pairs of frames (POFs) including a so-called previous frame and a so-called current frame, and the decomposition is applied to said GOFs together with motion estimation and compensation steps performed in each GOF on saids POFs and on corresponding pairs of low-frequency temporal subbands (POSs) obtained at each temporal decomposition level.

Abstract: The invention relates to a three-dimensional (3D) video coding method applied to a bitstream corresponding to an original video sequence that has been divided into successive groups of frames (GOFs). This coding method, applies to each successive GOF first a spatio-temporal analysis step, itself comprising a motion estimation sub-step, a motion compensated temporal filtering sub-step and a spatial analysis sub-step, and then an encoding step, itself comprising an entropy coding sub-step, performed on the low and high frequency temporal subbands resulting from the spatio-temporal analysis step and on motion vectors obtained by means of said motion estimation step, and an arithmetic coding sub-step, applied to the coded sequence thus obtained.

Abstract: The invention relates to a scalable video transcoding method for transcoding an input video signal (103) coded according to MPEG-2 video standard, resulting in four transcoding architectures. Scalability is obtained by means of to switches (120) and (130) determining whether or not reconstruction (118) and motion compensation (128) of the coding error (119) are performed. Each architecture thus defined having a different processing complexity, the overall processing resources available can be optimally used and minimized along a group of frames in the transcoding of parts of said frames in accordance with one of these four architectures, while ensuring a good video quality of tanscoded signal (109). A cost-effective control strategy of said switches based on an energy prediction of said coding error is also proposed.

Abstract: The invention relates to a video decoding method for the decompression of an input coded bitstream corresponding to an original video sequence. The sequence has been divided into successive groups of frames (GOFs) and coded by means of a three-dimensional subband video coding method. According to the invention, the decoding method is iterative and comprises as many iterations as the number of couples of frames in each GOF, each iteration itself including, for the reconstruction of each successive couple of frames of each GOF, the sub-steps of decoding the coded bitstream that corresponds to the current GOF, storing, from the decoded bitstream thus obtained, only the data related to the current couple of frames and appropriate subbands containing some information on at least one frame of said current couple of frames, and, from said related data and said appropriate subbands, synthesizing the two frames of said current couple of frames.

Abstract: The invention relates to a video encoding method for the compression of a video sequence, comprising the steps of generating from the original video sequence, by means of a wavelet decomposition, a low resolution sequence, performing on said low resolution sequence a low resolution decomposition, by means of a motion compensated spatio-temporal analysis, generating from said low resolution decomposition a full resolution sequence, by means of an anchoring of the high frequency sparial subbands resulting from the wavelet decomposition to said low resolution decomposition and coding said full resolution sequence and the motion vectors generated during the motion compensated spatio-temporal analysis. The invention also relates to a corresponding decoding method, and to corresponding encoding and decoding devices.

Abstract: The invention relates to a method of modifying data in an input coded video signal for generating an output scalable video signal composed of a base video signal and a set of at least one enhancement video signal, said method comprising at least an error decoding step for generating a decoded data signal from said input coded video signal, a first re-encoding step for generating said base video signal from an intermediate data signal resulting from the addition of a motion-compensated signal to said decoded data signal, a reconstruction step for generating a coding error of said base video signal, a motion compensation step for generating said motion-compensated signal from said coding error, a second re-encoding step for generating said enhancement video signal from said coding error. The coding error of said base video signal is re-encoded with a finer granularity than the one used for generating said base video signal.

Abstract: The invention relates to a video decoding method for decoding a set of video signals comprising a base layer signal and at least one enhancement layer signal and for supplying a decoded output signal, said decoding method comprising:

Abstract: The invention relates to a scalable video transcoding method for transcoding an input video signal (103) coded according to MPEG-2 video standard, resulting in four transcoding architectures. Scalability is obtained by means of to switches (120) and (130) determining whether or not reconstruction (118) and motion compensation (128) of the coding error (119) are performed. Each architecture thus defined having a different processing complexity, the overall processing resources available can be optimally used and minimized along a group of frames in the transcoding of parts of said frames in accordance with one of these four architectures, while ensuring a good video quality of tanscoded signal (109). A cost-effective control strategy of said switches based on an energy prediction of said coding error is also proposed.