Class / Patent application number | Description | Number of patent applications / Date published |
708402000 | Discrete Cosine Transform (i.e., DCT) | 14 |
20080215654 | Video Decoding with Reduced IDCT Calculations - Reduced complexity inverse discrete cosine transform (IDCT) masks and a method for reducing the number of IDCT calculations in video decoding are provided. The method comprises: accepting an n×m matrix of DCT coefficients; performing (n−y) horizontal IDCT operations, where y is greater than 0; performing y scaling operations; and, generating an n×m block of pixel information. Some aspects of the method further comprise: performing (m−z) vertical IDCT operations, where z is in the range between 0 and m/2. In some aspects, performing (n−y) horizontal ICDT operations includes performing IDCT operations for the first (n−y) horizontal rows. Then, performing y scaling operations includes: selecting the DC component from the first position of each horizontal row; scaling the selected DC component; and, copying the scaled DC component into the remaining positions of each of horizontal row. | 09-04-2008 |
20090150469 | UNIFIED INVERSE DISCRETE COSINE TRANSFORM (IDCT) MICROCODE PROCESSOR ENGINE - The present invention provides a unified inverse discrete cosine transform (IDCT) microcode processor engine, which is able to process IDCT with different video standards and also achieves the processing speed requirement. The microcode processor engine comprises a read unit for reading input data; a shift left unit comprising: a first shift left block for left-shifting input data; and a second shift left block for left-shifting input data; an add unit for adding data output from the shift left unit; and a shift right unit for right-shifting data output from the add unit. The present invention also provides a system of inverse discrete cosine transform. | 06-11-2009 |
20090157785 | FAST ALGORITHMS FOR COMPUTATION OF 5-POINT DCT-II, DCT-IV, AND DST-IV, AND ARCHITECTURES - A more efficient encoder/decoder is provided in which an N-point MDCT transform is mapped into smaller sized N/2-point DCT-IV, DST-IV and/or DCT-II transforms. The MDCT may be systematically decimated by factor of 2 by utilizing a uniformly scaled 5-point DCT-II core function as opposed to the DCT-IV or FFT cores used in many existing MDCT designs in audio codecs. Various transform factorizations of the 5-point transforms may be implemented to more efficiently implement a transform. | 06-18-2009 |
20090198757 | METHOD AND DEVICE FOR AVOIDING ROUNDING ERRORS AFTER PERFORMING AN INVERSE DISCRETE COSINE TRANSFORMATION - The present invention provides a method for avoiding rounding errors during rounding of values after performing an inverse discrete cosine transformation. In a first step a) coefficient values of a plurality of coefficients are summed up, wherein the coefficients belong to a block of coefficients. In a second step b), it is evaluated if the sum of the coefficient values is even numbered or odd numbered. In a third step c), then the coefficient block is transformed by means of the inverse discrete cosine transformation into a block of image pixels, wherein each image pixel comprises an image pixel value. In a fourth step d), a block of manipulation values is added or subtracted to the block of image pixel values of the block of image pixels, if the evaluation of the sum of the coefficient values has provided that the sum is even numbered, for generating a manipulated image pixel block, wherein the manipulation value block is formed such that rounding errors during a subsequent rounding operation can be avoided. | 08-06-2009 |
20100235421 | FAST DCT ALGORITHM FOR DSP WITH VLIW ARCHITECTURE - A single stage computation method to perform a discrete cosine transform operation is provided. The discrete cosine transform operation is performed by executing a plurality of very large instruction words (VLIW) using a digital signal processor. The plurality of very large instruction words includes a first number of multiplications and a second number of additions, where the first number of multiplications is greater than the second number of additions. | 09-16-2010 |
20100306298 | DEVICE FOR DFT CALCULATION - A device to perform DFT calculations, for example in a GNSS receiver, including two banks of multipliers by constant integer value, the values representing real and imaginary part of twiddle factors in the DFT. A control unit selectively routes the data through the appropriate multipliers to obtain the desired DFT terms. Unused multipliers are tied to constant input values, in order to minimize dynamic power. | 12-02-2010 |
20100312811 | 4X4 TRANSFORM FOR MEDIA CODING - In general, techniques are described that provide for 4×4 transforms for media coding. A number of different 4×4 transforms are described that adhere to these techniques. As one example, an apparatus includes a 4×4 discrete cosine transform (DCT) hardware unit. The DCT hardware unit implements an orthogonal 4×4 DCT having an odd portion that applies first and second internal factors (C, S) that are related to a scaled factor (ξ) such that the scaled factor equals a square root of a sum of a square of the first internal factor (C) plus a square of the second internal factor (S). The 4×4 DCT hardware unit applies the 4×4 DCT implementation to media data to transform the media data from a spatial domain to a frequency domain. As another example, an apparatus implements a non-orthogonal 4×4 DCT to improve coding gain. | 12-09-2010 |
20110072065 | Method for efficient DCT calculations in a programmable processor - The present invention relates to a efficient implementation of integer and fractional 8-length or 4-length, or 8×8 or 4×4 DCT in a SIMD processor as part of MPEG and other video compression standards. | 03-24-2011 |
20110137969 | APPARATUS AND CIRCUITS FOR SHARED FLOW GRAPH BASED DISCRETE COSINE TRANSFORM - An apparatus and circuit for performing a discrete cosine transformation of input signals. A discrete cosine transformation (DCT) apparatus includes a forward adder-tree module, a first set of multiplexers, a shared flow-graph module, an inverse adder-tree module, and a second set of multiplexers coupled in series. In operation, the multiplexers are configured to process input signals via the forward adder-tree module and the shared flow-graph module to perform a forward DCT of the input signals or via the shared flow-graph module and the inverse adder-tree module to perform an inverse discrete cosine transform of the input signals. | 06-09-2011 |
20110264723 | SYSTEM AND METHOD FOR SUCCESSIVE MATRIX TRANSPOSES - A system and method for successively transposing a matrix is disclosed. The device includes a plurality of data storage elements arranged as a two dimensional (2D) structure including X rows and Y columns. The device further includes write control logic coupled to the input of plurality of data storage elements for writing data in at least one virtual row. The device also includes read control logic coupled to the output of the plurality of data storage elements for reading the data from at least one virtual column, where the data write to the at least one virtual row and the data read from the at least one virtual column are performed substantially simultaneously during each cycle of operation such that the 2D structure is transposed successively with zero cycle delay between successive transposes. | 10-27-2011 |
20120016922 | Video Codec and Method thereof - A video codec method is provided, for processing video data processed by a Discrete Cosine Transformation (DCT) operation, comprising: (a) if a transformation matrix having a plurality of coefficients comprises at least one non-integer coefficient among the coefficients, multiplying the transformation matrix by a multiplication factor α to make all coefficients of the transformation matrix integers, (b) estimating a compensation set, (c) performing a Column in Row out IDCT two-dimensional operation on the video data according to the transformation matrix and the compensation set, to obtain a compensated two-dimension operation result, (d) selectively dividing the compensated two-dimension operation result by α | 01-19-2012 |
20120078990 | SIGNAL PROCESSING DEVICE AND IMAGE PROCESSING DEVICE - A signal processing device and an image processing device are provided. The signal processing device includes a matrix calculator for performing a matrix operation selected by a switch part among a DCT matrix operation, a Haar matrix operation, and a Slant matrix operation, with respect to an input signal. Thus, the signal processing device can be implemented in a hybrid architecture capable of selectively processing the DCT-II transform, the Haar transform, and the Slant transform with a single chip. | 03-29-2012 |
20130173679 | RECURSIVE TYPE-IV DISCRETE COSINE TRANSFORM SYSTEM - A recursive type-IV discrete cosine transform system includes a first permutation device, a recursive type-III discrete cosine/sine transform device, a cosine/sine factor generation device, a recursive type-II discrete cosine/sine transform device, a second permutation device. The first permutation device performs two-dimensional order permutation operation on N digital signals for generating N two-dimensional first temporal signals. The recursive type-III discrete cosine/sine transform device repeats a type-III discrete cosine/sine transform for generating second temporal signals. The cosine/sine factor generation device sequentially performs cosine/sine factor multiplication and corresponding addition operations for generating third temporal signals. The recursive type-II discrete cosine/sine transform device repeats a type-II discrete cosine/sine transform for generating fourth temporal signals. The second permutation device performs a one-dimensional order permutation operation for generating N one-dimensional output signals. The N one-dimensional output signals are obtained by performing a type-IV discrete cosine transform on the N digital input signals. | 07-04-2013 |
20130318141 | Systems and Methods for Generating Updates of Geological Models - Systems and methods for generating updates of large scale 3D geological models with multi-model facies, permeability or porosity distribution. | 11-28-2013 |