Method of processing signal data on the basis of principal component transform, apparatus for performing the method
First Claim
Patent Images
1. Method of compressing signals generated from and representing an image or speech on the basis of a Principal Component Transform, comprising:
- determining an approximation of a statistically most significant eigenvector of a covariance matrix associated with signal data generated from and representing an image or speech represented in a vector space,taking an initial vector in said vector space as a first estimate;
for each next estimate determining a linear combination of the preceding estimate and a next vector in said vector space, said next vector being weighted with a factor that depends on an inproduct of the preceding estimate and said next vector for enhancing the next estimate into a direction of the preceding estimate,upon termination of determining next estimates taking said approximation parallel to the last obtained estimate, to produce a compressed signal representing the same image or speech.
0 Assignments
0 Petitions
Accused Products
Abstract
A method is proposed for determining approximations of eigenvectors of a covariance matrix associated with signal data on the basis of the Principal Component Transform. Successive iterations on estimates enhance the development into the direction of the principal component considered. The method is applicable to the Singular Value Decomposition of data matrices. The operations to be performed are similar to those required in a neural net for adapting the synaptic coefficients, Apparatus are proposed for performing the method.
-
Citations
16 Claims
-
1. Method of compressing signals generated from and representing an image or speech on the basis of a Principal Component Transform, comprising:
-
determining an approximation of a statistically most significant eigenvector of a covariance matrix associated with signal data generated from and representing an image or speech represented in a vector space, taking an initial vector in said vector space as a first estimate; for each next estimate determining a linear combination of the preceding estimate and a next vector in said vector space, said next vector being weighted with a factor that depends on an inproduct of the preceding estimate and said next vector for enhancing the next estimate into a direction of the preceding estimate, upon termination of determining next estimates taking said approximation parallel to the last obtained estimate, to produce a compressed signal representing the same image or speech.
-
-
2. A method of processing electrical data signals generated from and representing images or speech, using a digital data processing apparatus, to provide a revised representation of the image-representing electrical signals for use in compressing the electrical data signals, or for extracting features of the electrical data signals, or for modifying the electrical data signals to represent a rotation of the image, the method comprising the steps of
a) using the digital data processing apparatus, creating a covariance matrix representation of the electrical data signals; -
b) using the digital data processing apparatus, determining an approximation of at least a most significant eigenvector of the covariance matrix, the determining including; i) choosing an arbitrary vector as a first estimate; ii) creating a next estimate by determining a linear combination of a preceding estimate and a next vector, which linear combination includes weighing the next vector with a factor that depends on an inner product of the preceding estimate and said next vector, to enhance the next vector in a direction of the preceding estimate; and iii) after at least one application of step b) ii), using a last obtained value of the next estimate as the approximation; and c) providing electrical signals representing the eigenvectors as the revised representation of the images or speech for further processing. - View Dependent Claims (5, 6, 9, 10, 11, 12)
-
-
3. A method for processing electrical data signals generated from and representing images or speech, using a digital data processing apparatus, to provide a revised representation of the electrical data signals for use in compressing the electrical data signals, or for extracting features of the electrical data signals, or for modifying the electrical data signals to represent a rotation of the image, the method comprising the steps of
a) using the digital data processing apparatus, providing signals representing an initial output vector as a representation of the image data signals as a first output estimate of a first output base vector; -
b) using the digital data processing apparatus, providing signals representing an initial input vector as a representation of image signals in an input space and as a first input estimate of a first input base vector, which initial input vector is substantially linearly related to the initial output vector; c) using the digital data processing apparatus, creating a next output estimate by providing signals representing a linear combination of a preceding estimate and a next output vector, which linear combination includes weighing the next output vector with a factor that depends on an inner product of the preceding estimate and said next output vector, to enhance the next vector in a direction of the preceding estimate; d) using digital data processing apparatus, creating a next input estimate by providing signals representing a linear combination of a preceding input estimate and a next input vector, which linear combination includes weighing the next input vector with said factor, in order to keep the next output estimate substantially linearly related to the next input estimate; e) after at least one application of steps c) and d), using the digital data processing apparatus, providing signals representing a normalization of a last obtained value of the next input estimate and the next output estimate onto a unit length, to yield the first input base vector and the first output base vector, respectively, f) using the digital data processing apparatus, providing signals representing the input and output base vectors as the revised representation of the images or speech for further processing. - View Dependent Claims (7, 8, 13, 14, 15, 16)
-
-
4. Method of compressing signals generated from and representing images or speech utilizing the Singular Value Decomposition, comprising:
-
a. representing said signal data by input vectors in an input vector space and output vectors in an output space, each output vector being substantially linearly related to a respective input vector, b. taking an initial output vector as a first output estimate for a first output base vector; taking an initial input vector related to said output vector as a first input estimate for a first input base vector; c. for each next output estimate determining a linear combination of the preceding output estimate and a next output vector, the latter being weighted with a factor depending on an inproduct of the preceding output estimate and said next output vector for enhancing the next output estimate into a direction of the preceding output estimate; d. for each next input estimate determining a linear combination of the preceding input estimate and a next input vector, the latter being weighted with said factor for keeping the next output estimate substantially linearly related to the next input estimate; e. upon termination of determining a next output estimate and a next input estimate normalizing the last obtained output estimate and the last obtained input estimate onto unit length for producing the first output base vector and the first input base vector, respectively, and providing the first output base vector as output signals for use in deriving a compression representation.
-
Specification