Abstract: Embodiments of a two-dimensional pyramid filter architecture are described.

Abstract: Embodiments of a two-dimensional pyramid filter architecture are described.

Abstract: Embodiments of a two-dimensional pyramid filter architecture are described.

Abstract: Embodiments of a two-dimensional pyramid filter architecture are described.

Abstract: A method for implementing a filter on a signal is disclosed wherein interval membership information is computed and stored in such a manner so as to use a minimal amount of memory thereby allowing filter computation by a small number of deterministic sequence of table lookups and bit-wise logical operations. In general, the present invention involves using a non-linear filter represented as a plurality of intervals and the discrete values a sample may take. Each sample corresponds to a component in a vector. Each interval is comprised of a lower and upper vector. Each sample value is compared to the lower and upper values of the sample's associated coordinate. A table for that sample is then constructed with binary entries where a ‘1’ denotes that a sample value is within the lower and upper values of the coordinate and ‘0’ denoting otherwise. A table is built for each sample.

Abstract: An image processing method using memory management and pre-computed look up tables to speed up computations. Application of filters along directions other than image rows is simplified using several structured processing approaches that improve image data cache-ability. Time consuming or repeated computations are pre-computed and stored as look up tables to reduce the time required for image processing and to remove or reduce the need for special purpose image processing hardware.

Abstract: Interpolating filter banks are constructed for use with signals which may be represented as a lattice of arbitrary dimension d. The filter banks include M channels, where M is greater than or equal to two. A given filter bank is built by first computing a set of shifts &tgr;i as D−1 t1, i=1, 2, . . . M−1, where ti is a set of coset representatives taken from a unit cell of the input signal lattice, and D is a dilation matrix having a determinant equal to M. A polynomial interpolation algorithm is then applied to determine weights for a set of M−1 predict filters Pi having the shifts &tgr;1. A corresponding set of update filters Ui are then selected as Ui=Pi*/M, where Pi* is the adjoint of the predict filter Pi. The resulting predict and update filters are arranged in a lifting structure such that each of the predict and update filters are associated with a pair of the M channels of the filter bank.

Abstract: A rank filter suitable for use in real-time signal processing and image processing applications, for example, for improving an image. The rank filter can be implemented in software or hardware, employed in single- and multi-dimensions, and within any specified window. A link-list algorithm is combined with a memory array for storing and ordering the data.

Abstract: Two implementations of the inverse wavelet transform for use in an image decompression system do not waste computation power on the zero-valued values inserted into the data stream during an upsampling process. The implementation optimized for low-bandwidth applications toggles between even and odd modes each clock cycle. In even/odd mode, the transformed values are multiplied by the even/odd filter coefficients. The implementation optimized for high-bandwidth applications multiplies the transformed values by the even and odd filter coefficients seperately in two sets of multipliers and outputs two different results each clock cycle.

Abstract: DSP error detection and filtering of a modem signal using a simple, robust, and low cost technique. The DSP technique utilizes a equalizer/filter to adjust the amplitude and phase delay of the transmitted data signal. The modem on the DSP chip may include a demodulator, parser/interpreter module, start and stop bit module, and modulator. The demodulator may include a switch, equalizer/filter, processing module, bit converter, adder, and averaging module. The averaging module computes an average value for the error signal during the frame training sequence. The error signal is the output of the bit converter minus the output of the demodulator. After each bit of the error signal is fed into the averaging module, the averaging module computes a new average. The averaging module performs an adaptive process. The average value of the error signal is compared to a threshold value.

Abstract: Methods for generating and implementing digital orientational filters. A first method of the present invention is provided for generating digital orientational filters of uniform size but each having a different fixed orientation. A second method provides for dilation of the digital orientation filters generated by the first method, both in a decimated and an undecimated format. A third method of the present invention provides for steering the orientation of the filters generated by the first method. Also, associated VLSI hardware based systems implementing the above methods are disclosed. The above methods and systems allow digital orientational filters to be utilized in computer vision and other applications requiring a large amount of video signal data to be processed in real-time.

Abstract: A digital filter processing device receives image data of a frame in the order of time series in scanning the frame for carrying out a filter process for every group of image data corresponding to each of a plurality of regions of a predetermined size in the frame. The device receives image data in the order of time series of the scanning operation of a frame to multiply the input image data by a corresponding filter coefficient. This multiplied result is accumulated for every group to be output as an accumulation result. As a result, a region for storing a multiplied result which is an intermediate result of the filter process and an operation for reading out the multiplied result from the storage region for accumulation can be eliminated. Therefore, a filtering process of a frame can be carried out at high speed and in real-time.