Abstract: The present invention relates to a method and an encoder for coding an input digital video signal comprising a luminance component with luminance values. The method comprises the steps of:- transforming said video sequence from the original spatial representation into fewer representation data comprising transformed luminance values;—performing a quantization on the representation data so as to obtain a reduced set of data. The invention is characterized in that the quantization step performs a quantization of the luminance component in an adaptive way according to a visible range of transformed luminance values of the luminance component.

Abstract: The present invention relates to a method and an encoder for processing a digital video signal, said digital video signal comprising at least a scene cut (CUT) followed by a set of images. It is characterized in that it comprises the steps of:—Localizing said scene cut (CUT),—Defining a sub set of visually non-relevant images (IS) within said set of images, and—Issuing a set of encoded visually non-relevant images (IS?) just after the scene cut (CUT) by calculating said set from a visually relevant image (I(to+2)) after said scene cut (CUT).

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 information indicating at a high description level in said bitstream the presence, or not, of various additional channels that can be encountered to describe the content of said bitstream. Several examples of specific information are given.

Abstract: The invention relates to a method of coding an input digital video sequence corresponding to an original color image sequence, said method comprising at least a step for converting said video sequence from the spatial domain to less representation data, a quantization step, for transforming the converted signals thus obtained into a reduced set of data. According to the invention, said coding method also comprises, before said converting step, a pre-processing step, provided for determining if the input video sequence is in YUV color space, Y being the luminance component and U, V the chrominance components, and transforming said space into a less redundant color space by means of a non-linear transformation taking into account the possible lower quality finally obtained.

Abstract: The invention relates to a method of coding an input digital video sequence corresponding to an original color image sequence, said method comprising at least a step for converting the video sequence from the spatial domain to less representation data, a quantizing step, for transforming the converted signals thus obtained into a reduced set of data, and a step for coding said quantized data. According to the invention, said coding method also comprises, before said converting step, a preprocessing step, provided for determining if the input video sequence is in the YUV color space and then transforming said YUV color space into a less redundant color space by means of a non-linear transformation.

Abstract: The invention relates to a video coding method and device applied to a sequence of frames and generating a coded bitstream in which each data item is described by means of a bitstream syntax allowing any decoder to recognize and decode all the elements of the content of said bitstream. According to the invention, which finds an application for instance within the video compression standard MPEG-4, the syntax comprises a specific one bit flag provided for indicating at a high level description the presence, or not, of a shape for each video object of the scenes of the sequence. This flag is transmitted in the coded bitstream, and its value is read at the decoding side for controlling correspondingly the decoding step.

Abstract: The invention relates to a video coding method applied to a sequence of frames and generating a coded bitstream in which 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. According to the invention, which finds an application for instance within the video compression standards of the MPEG and ITU-H.26X families, the syntax comprises a flag provided for indicating at a high description level, for each channel described in the coded bitstream, the presence, or not, of an encoded residual signal, said residual being defined by means of a prediction technique, applied to previously decoded frames and followed by the construction of said residual signal.

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 invention relates to a video coding method applied to an input signal IS consisting of a sequence of frames represented by one luminance matrix and two chrominance matrices. This method generates a coded bitstream CB in which 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. According to the invention, which finds an application for instance within the video compression standards of the MPEG and ITU-H.26X families, the syntax comprises a flag provided for indicating at a high level description the presence, or not, of chrominance components in said coded bitstream, and therefore allowing to deliver, at the decoding side, the information according to which chrominance descriptive elements have to be decoded, or not.