Abstract: A method for processing seismic data includes receiving seismic data and a velocity model (c(x)) for a plurality of locations (x), scaling a dimension of the seismic data according to the velocity model (c(x)) to provide a velocity normalized seismic data, and generating a final image (S(x)) of the subsurface using the velocity normalized seismic data. The velocity normalized seismic data may be a reverse-time migration image (I(x,?)) corresponding to the plurality of locations (x) and a plurality of propagation distance offsets (?). The method may also include transforming the reverse-time migration image (I(x,?)) for the plurality of selected positions (x) to a wavenumber domain to provide velocity normalized wavenumber data (I(k,?)) and suppressing data components corresponding to non-physical or undefined reflection angles to provide enhanced wavenumber data (I?(k,?)) and using the enhanced wavenumber data (I?(k,?)) to generate the final image (S(x)). A corresponding apparatus is also disclosed herein.

Abstract: An efficient and accurate classification method for classifying speech and music signals, or other diverse signal types, is provided. The method and system are especially, although not exclusively, suited for use in real-time applications. Long-term and short-term features are extracted relative to each frame, whereby short-term features are used to detect a potential switching point at which to switch a coder operating mode, and long-term features are used to classify each frame and validate the potential switch at the potential switch point according to the classification and a predefined criterion.

Abstract: A method for optimizing a wavelet packet structure for subsequent tree-structured coding which preserves coherent spatial relationships between parent coefficients and their respective four offspring at each step. A valid frequency tree is defined by a wavelet packet decomposition algorithm. Constraints are placed on the pruning of the frequency tree in order to select valid frequency trees as each step. These constraints include considering any four offspring sub-bands as candidates for pruning only when their current frequency decomposition level is the same as that of their respective spatially co-located parent sub-band, and pruning the spatially co-located offspring sub-bands when pruning only the parents results in an invalid wavelet packet structure.

Abstract: An efficient and accurate classification method for classifying speech and music signals, or other diverse signal types, is provided. The method and system are especially, although not exclusively, suited for use in real-time applications. Long-term and short-term features are extracted relative to each frame, whereby short-term features are used to detect a potential switching point at which to switch a coder operating mode, and long-term features are used to classify each frame and validate the potential switch at the potential switch point according to the classification and a predefined criterion.