Abstract: The present invention relates to a method and device (580) for encoding three-dimensional video data, the device comprising: a first encoder (505) arranged to encode multiple simultaneous views (501) of a scene from different viewpoints; a second encoder (510) arranged to encode depth information of the scene and a third encoder (515) arranged to encode additional information indicative of a relationship between the multiple views and the depth information and a combiner (520) arranged to combine the encoded information into a representation (513) of the three-dimensional video data. The additional information comprises a group classifier indicating whether or not the depth information and at least one of the multiple views correspond to the same source material for, when corresponding, using the depth information and the at least one of the multiple views to render further views of the scene from further different viewpoints.

Abstract: The present invention relates to a method and device (580) for encoding three-dimensional video data, the device comprising: a first encoder (505) arranged to encode multiple simultaneous views (501) of a scene from different viewpoints; a second encoder (510) arranged to encode depth information of the scene and a third encoder (515) arranged to encode additional information indicative of a relationship between the multiple views and the depth information and a combiner (520) arranged to combine the encoded information into a representation (513) of the three-dimensional video data. The additional information comprises a group classifier indicating whether or not the depth information and at least one of the multiple views correspond to the same source material for, when corresponding, using the depth information and the at least one of the multiple views to render further views of the scene from further different viewpoints.

Abstract: The bitrate control of known video encoders is based on a control of the quantization step size per picture block. In transform coding of relatively large picture blocks, the video picture comprises a too small number of picture blocks to obtain a desired number of bits per picture. In conformity with the invention, the target value for the number of bits per picture block is divided into N sub-targets (Rt(k,n)). The series of coefficients of a picture block is divided into N segments (L(n)) with reference to an estimation for the cumulative distribution 20 of the bit cost per picture block. The quantization step size is subsequently adapted per segment to the corresponding sub-target. Since the number of segments is N times larger than the number of picture blocks, an accurate bitrate control is possible. If desired, the estimation for the cumulative distribution is adapted from picture to picture.

Abstract: An information stream organized as a sequence of blocks is encoded according to a graceful degradation principle. The stream poses temporal non-uniform data processing requirements. In particular, with respect to a received block one or more blockwise defined control parameters and an associated blockwise processing load are detected (44). Under control (46) of a processing load for one or more previous blocks, one or more later blocks before processing thereof get an adjustment (48) of one or more of the control parameters. This lowers an expected load for the later block in case of an excessive load, and vice versa when detecting a sub-standard load.

Abstract: A method of encoding images (1) including areas (11) of relevant pixels and areas (12) of irrelevant pixels (e.g. a background) is disclosed. The pixels of the irrelevant area are replaced (4) by pseudo-pixels smoothing the transition between said areas. The image thus obtained is subsequently subjected to conventional image coding (5) which now yields considerably fewer bits. At the receiver end, the pseudo-pixels are replaced (9) by predetermined background pixels to reconstruct the original boundaries (13). If the boundary between both areas is not known in advance, the boundary is detected (2), encoded (3) and transmitted to the receiver. The invention is particularly applicable to compression of medical images having circular areas of interest, but may also be used to encode other video images having irrelevant areas such as videophone images in which a head-and-shoulder area constitutes relevant information only.

Abstract: An information stream organized as a sequence of blocks is encoded according to a graceful degradation principle. The stream poses temporal non-uniform data processing requirements. In particular, with respect to a received block one or more blockwise defined control parameters and an associated blockwise processing load are detected. Under control of a processing load for one or more previous blocks, one or more later blocks before processing thereof get an adjustment of one or more of the control parameters. This lowers an expected load for the later block in case of an excessive load, and vice versa when detecting a sub-standard load.

Abstract: An information stream organized as a sequence of blocks is encoded according to a graceful degradation principle. The stream poses temporal non-uniform data processing requirements. In particular, with respect to a received block one or more blockwise defined control parameters and an associated blockwise processing load are detected (44). Under control (46) of a processing load for one or more previous blocks, one or more later blocks before processing thereof get an adjustment (48) of one or more of the control parameters. This lowers an expected load for the later block in case of an excessive load, and vice versa when detecting a sub-standard load.

Abstract: An audio and/or video information stream organized as a sequence of pictures is encoded through an at least partly software-based procedure. The sequence includes Intrapictures, Predictive pictures, and Bidirectional predictive pictures. In particular, for a substantial and predictively located selection (77) among said Bidirectional predictive pictures only one prediction direction is used (76). For any remaining Bidirectional predictive picture both prediction directions are maintained.

Abstract: A device comprising an MPEG encoder (2) is provided with a preanalyser (8) which encodes each picture with a fixed step size (Q.sub.2). The preanalyser is coupled to a computing circuit (9) which computes, for each type of (I, P, B) picture, a target value (T) for the number of bits for encoding said picture, as well as a suitable distribution of the target value among the macroblocks of the picture. A proportionally integrating control circuit (7) controls the quantization step size (Q.sub.1). Since the PI control circuit does not introduce any residual errors, the desired number of bits per picture or per group of pictures is achieved within narrow limits. The output signal is eminently suitable for recording and subsequent editing.

Abstract: A device for encoding a video signal comprises a picture transformer (22), a quantizer (23) and a variable-length encoder (24), as well as distribution device (6) for distributing a global target value (T) for the number of bits per picture or group of pictures in local target values (T.sub.n) for separate macroblocks of each picture. The device for encoding is provided with proportionally integrating control device for for controlling the quantization step size (Q.sub.1) in such a way that the buffer contents (b) of an output buffer (4) are in conformity with the target value. Since the PI control circuit does not introduce any residual errors, the desired number of bits per picture or group of pictures is achieved within narrow limits. The output signal is eminently suitable for recording and subsequent editing.