Abstract: When packing a video frame of a higher-resolution chroma sampling format such as YUV 4:4:4 into frames of a lower-resolution chroma sampling format such as YUV 4:2:0, a computing device performs wavelet decomposition (or other band separation filtering) on sample values of chroma components of the higher-resolution frame, producing sample values of multiple bands. The device assigns the sample values of the bands to parts of the lower-resolution frames. During corresponding unpacking operations, a computing device assigns parts of the frames of the lower-resolution chroma sampling format to sample values of multiple bands. The device performs wavelet reconstruction (or other inverse band separation filtering) on the sample values of the bands, producing sample values of chroma components of the frame of the higher-resolution chroma sampling format.

Abstract: An improved method and block transform for image or video encoding and decoding, wherein transformation and inverse transformation matrixes are defined such that computational complexity is significantly reduced when encoding and decoding. For example, in the two-dimensional inverse transformation of de-quantized transform coefficients into output pixel information during decoding, only four additions plus one shift operation are needed, per co-efficient transformation, all in sixteen-bit arithmetic. Transformations provide correct results because quantization during encoding and de-quantization (sixteen bit) during decoding, via the use of one of three tables selected based on each coefficient's position, have parameter values that already compensate for factors of other transformation multiplications, except for those of a power of two, (e.g., two or one-half), which are performed by a shift operation during the transformation and inverse transformation processes.

Abstract: When packing a video frame of a higher-resolution chroma sampling format such as YUV 4:4:4 into frames of a lower-resolution chroma sampling format such as YUV 4:2:0, a computing device performs wavelet decomposition (or other band separation filtering) on sample values of chroma components of the higher-resolution frame, producing sample values of multiple bands. The device assigns the sample values of the bands to parts of the lower-resolution frames. During corresponding unpacking operations, a computing device assigns parts of the frames of the lower-resolution chroma sampling format to sample values of multiple bands. The device performs wavelet reconstruction (or other inverse band separation filtering) on the sample values of the bands, producing sample values of chroma components of the frame of the higher-resolution chroma sampling format.

Abstract: An efficient lapped transform is realized using pre- and post-filters (or reversible overlap operators) that are structured of unit determinant component matrices. The pre- and post-filters are realized as a succession of planar rotational transforms and unit determinant planar scaling transforms. The planar scaling transforms can be implemented using planar shears or lifting steps. Further, the planar rotations and planar shears have an implementation as reversible/lossless operations, giving as a result, a reversible overlap operator.

Abstract: A transform coder is described that performs a time-split transform in addition to a discrete cosine type transform. A time-split transform is selectively performed based on characteristics of media data. Transient detection identifies a changing signal characteristic, such as a transient in media data. After encoding an input signal from a time domain to a transform domain, a time-splitting transformer selectively perform an orthogonal sum-difference transform on adjacent coefficients indicated by a changing signal characteristic location. The orthogonal sum-difference transform on adjacent coefficients results in transforming a vector of coefficients in the transform domain as if they were multiplied by an identity matrix including at least one 2×2 time-split block along a diagonal of the matrix. A decoder performs an inverse of the described transforms.

Abstract: An efficient lapped transform is realized using pre- and post-filters (or reversible overlap operators) that are structured of unit determinant component matrices. The pre- and post-filters are realized as a succession of planar rotational transforms and unit determinant planar scaling transforms. The planar scaling transforms can be implemented using planar shears or lifting steps. Further, the planar rotations and planar shears have an implementation as reversible/lossless operations, giving as a result, a reversible overlap operator.

Abstract: An efficient lapped transform is realized using pre- and post-filters (or reversible overlap operators) that are structured of unit determinant component matrices. The pre- and post-filters are realized as a succession of planar rotational transforms and unit determinant planar scaling transforms. The planar scaling transforms can be implemented using planar shears or lifting steps. Further, the planar rotations and planar shears have an implementation as reversible/lossless operations, giving as a result, a reversible overlap operator.

Abstract: Methods for coding a time-dependent geometry stream include a basis decomposition coder and a column/row prediction coder. The basis decomposition coder uses principal component analysis to decompose a time dependent geometry matrix into basis vectors and weights. The weights and basis vectors are coded separately. Optionally, the residual between a mesh constructed from the weights and basis vectors and the original mesh can be encoded as well. The column/row predictor exploits coherence in a matrix of time dependent geometry by encoding differences among neighboring rows and columns. Row and column sorting optimizes this form of coding by re-arranging rows and columns to improve similarity among neighboring rows/columns.

Abstract: The coder/decoder (codec) system of the present invention includes a coder and a decoder. The coder includes a multi-resolution transform processor, such as a modulated lapped transform (MLT) transform processor, a weighting processor, a uniform quantizer, a masking threshold spectrum processor, an entropy encoder, and a communication device, such as a multiplexor (MUX) for multiplexing (combining) signals received from the above components for transmission over a single medium. The decoder comprises inverse components of the encoder, such as an inverse multi-resolution transform processor, an inverse weighting processor, an inverse uniform quantizer, an inverse masking threshold spectrum processor, an inverse entropy encoder, and an inverse MUX. With these components, the present invention is capable of performing resolution switching, spectral weighting, digital encoding, and parametric modeling.

Abstract: The method captures a 3D model of a face, which includes a 3D mesh and a series of deformations of the mesh that define changes in position of the mesh over time (e.g., for each frame). The method also builds a texture map associated with each frame in an animation sequence. The method achieves significant advantages by using markers on an actor's face to track motion of the face over time and to establish a relationship between the 3D model and texture. Specifically, videos of an actor's face with markers are captured from multiple cameras. Stereo matching is used to derive 3D locations of the markers in each frame. A 3D scan is also performed on the actor's face with the markers to produce an initial mesh with markers. The markers from the 3D scan are matched with the 3D locations of the markers in each frame from the stereo matching process. The method determines how the position of the mesh changes from frame to frame by matching the 3D locations of the markers from one frame to the next.