Abstract: Techniques related to graphics rendering including techniques for compression and/or decompression of graphics data by use of pixel region bit values are described.

Abstract: In an image processing device, an information processing section performs information processing according to an instruction input by a user. An alpha buffer generating block of an image processing section generates an alpha buffer representing, in an image plane, the alpha value of each pixel when designated objects formed by a plurality of objects are collectively regarded as one object. A rendering block reads each piece of model data from an image data storage section, and renders an image also including other objects than the designated objects. A shading processing block approximately calculates degrees of occlusion of ambient light on the image plane, and subjects the rendered image to shading processing on a basis of a result of the calculation.

Abstract: A method for encoding pictures within a groups of pictures using prediction, where a first reference picture from a group of pictures and a second reference pictures from the subsequent group of pictures are used in predicting pictures in the group of pictures associated with the first reference picture. A plurality of anchor pictures in the group of pictures associated with the first reference picture may be predicted using both the first and second reference pictures to ensure a smooth transition between different groups of pictures within a video frame.

Abstract: In video coding, prediction of P- and B-frames is based on reference frames, which are indicated by reference picture lists. Scalable video coding (SVC) requires this for both, base-layer and enhancement-layer. The invention describes a decoding process for reference picture list construction for spatial enhancement layer. With just one flag of syntax modification, it provides simpler and direct reference lists construction process. By using this, complicated RPLR and other syntaxes can be skipped, and the RPLR process for spatial enhancement layer can also be avoided. The process also can be used as for error concealment when the spatial enhancement layer slice is lost.

Abstract: A video sequence including images in the form of digital samples is encoded by: subsampling the video sequence to produce: a number N of multiple descriptions of the video sequence, each multiple description including 1/N samples of the video sequence, and a subsampled version of the sequence, the subsampled version having a resolution lower or equal to the resolution of the N multiple descriptions. The N multiple descriptions and the subsampled version are subjected to scalable video coding (SVC) to produce an SVC encoded signal having a base layer and N enhancement layers predicted from said base layer. The subsampled version of the sequence and the N multiple descriptions of the video sequence constitute the base layer and the enhancement layers, respectively, of the SVC encoded signal.

Abstract: Provided are a device and method for providing a video stream, in which a hash value of a frame is included in the header of a video stream, and authentication information about the header is inserted into the video stream, thus ensuring integrity against the forgery of the video stream. The device includes a base frame encoding unit which encodes a base frame, an enhancement frame encoding unit which encodes an enhancement frame, a frame encryption unit which encrypts the encoded base frame and the encoded enhancement frame, a hash processing unit which calculates hash values for the encrypted base frame and the encrypted enhancement frame and hash values included in headers of previous and subsequent video streams, a header management unit which includes information about the encoded base frame and the encoded enhancement frame and the calculated hash values, in a header, and manages the header, and an authentication information creation unit which creates authentication information about the header.

Abstract: A method for estimating quality of images compressed with a transformation based compression method. The estimation method uses estimated errors generated by quantization to obtain an image quality indicator and does not require use of a reference image. The estimation method includes calculating a probability of at least one specific quantized transformation coefficient value for at least all coefficients representing one identical two-dimensional frequency, and estimating identifying parameters of at least one probability density function of non-quantized coefficient values from the quantized coefficient value probabilities, with a type of probability density function being preset. The estimation method further includes calculating an image quality indicator from errors introduced by quantization, which are derived from probability density function parameters and quantization parameters.

Abstract: An exemplary system includes a data encoder generating a base layer bitstream encoded at a base bit-rate, and a plurality of enhancement layer bitstreams encoded at different enhancement layer bit-rates, and a bitstream selection module selecting one of the enhancement layer bitstreams every video frame based on available channel bandwidth. A method includes transmitting a first enhancement layer bitstream encoded at a first bit-rate, detecting a transition in network bandwidth through a switching bit-rate, and transmitting a second enhancement layer bitstream encoded at a second bit-rate based on the transition in network bandwidth.