Canon Kabushiki Kaisha

Canon Research Centre France S.a.

F&eacute;lix Henry

Eric Majani

Bertrand Berthelot

Jean-Jacques Moreau

Maryline Charrier

Claude Dierieck

Method of modifying the geometric orientation of an image

A system for recording information relating to a document, which is accessible via a computer communication network, operates by extracting key words associated with the document, associating a binary code with each extracted key word to form associations, storing the associations in a dictionary, and storing an electronic address (URL) of the document and the binary codes in association with each other in an information storage unit of a user.

Method and device for recording and searching for a document on a communication network

The invention concerns a method of coding a set of coefficients representing physical quantities. The method includes the step of selecting, for each coefficient to be coded, a first or second coding mode according to a coding cost, the first coding mode including the calculation of an amplitude model, and the determination of a path (P) amongst the coefficients. The method also includes the steps of coding the length of the path, coding the coefficients for which the first coding mode has been selected, by the first coding mode, and coding the coefficients for which the second coding mode has been selected, by the second coding mode.

Digital signal coding and decoding

A trellis filtering of a digital signal is disclosed. A method is provided of analysis filtering of an original digital signal including original samples representing physical quantities. Original samples of the digital signal are transformed by successive calculation steps into high and low frequency output samples. Any sample calculated at a given step is calculated by a predetermined function of original samples, and/or previously calculated samples, the samples being ordered in increasing rank. The signal is processed by successive series of samples, the calculations made on any series not taking into account the samples in a following series, and in that the any series terminates in a low-frequency sample.

Device and method for transforming a digital signal

A method for the geometric transcoding of a compressed data file containing a digital signal of dimension N coded by means of a coding method including at least one step of spectral breakdown into frequency subbands of the digital signal (S). The method includes the steps of extracting symbols associated with the coefficients of the frequency sub-bands of the digital signal and applying a geometric transformation to the symbols. The method further includes the steps of updating N indicator or indicators representing a normal or reversed order of the symbols respectively in N direction or directions of the digital signal and reconstituting the digital signal coded by reversal of the extracting step.

Geometric transcoding of a digital signal

A method and a device by which original digital signals are analysis-filtered, where the original digital signals include original samples representing physical quantities, and where the original samples are transformed by successive calculation steps into high and low frequency output samples. Any sample calculated at a given step is calculated by a predetermined function of the original samples and/or previously calculated samples, where the samples are ordered by increasing rank. The signal is processed by successive input blocks of samples, where the calculations made on an input block under consideration take into account only the original or calculated samples belonging to the input block under consideration, and where the input block under consideration and the following input block overlap over a predetermined number of original samples. Output blocks are formed, where each output block corresponds respectively to an input block.

In order to code a digital signal, a simplified version of the digital signal is determined, containing only some of the information contained in the digital signal. The simplified version is coded by means of a predetermined single coding technique. This simplified version is subtracted from the digital signal, so as to obtain a residual signal. From each block of the simplified version, there is selected, for each corresponding block of the residual signal, a coding technique amongst a predetermined number M of coding techniques Ci, where i is an integer between 1 and M. Each block of the residual signal is coded by means of the previously selected coding technique.

Methods and devices for coding and decoding digital signals, and systems using them

Conversion of digital data into bit-map mode

Methods and devices for processing data and notably for compressing and decompressing images

In order to code a digital signal, it is decomposed (,) into several subsignals; each subsignal is coded (,) by means of a coding technique taken from amongst M coding techniques Ci; and the stream of coded bits thus produced is entered (,) in a first part of a file intended to receive the coded digital signal. Then the application, successively to each coded subsignal, of each decoding technique Di associated with the coding technique Ci is simulated (,); and if and only if at least two different decoding techniques are acceptable, within the meaning of a predetermined likelihood criterion, for decoding the same coded subsignal, there is entered (,) in a second part of the file information making it possible to select, during decoding, the decoding technique associated with the coding technique used for coding this subsignal.

Digital signal huffman coding with division of frequency sub-bands

A method and apparatus for decoding a quantized digital signal. Quantization symbols are read and an experimental distribution of the quantization symbols is constructed. An experimental distribution is approximated by means of a continuous distribution model which passes through values of the experimental distribution. A dequantization vector, for at least one quantization cell, equal to the center of mass of the points of the quantization cell weighted by the values of the restricted continuous distribution is calculated. The dequantization vectors associated respectively with the quantization symbols are then stored for use in decoding.

Growing community of inventors

Rennes, France

Félix Henry

Growing community of inventors

Rennes, France

F&eacute;lix Henry

Félix Henry