Mitsubishi Denki Kabushiki Kaisha

Fumitaka Ono

Tomohiro Kimura

Masayuki Yoshida

Ikuro Ueno

Taichi Yanagiya

Kunio Ueda

Shigenori Kino

Narihiro Matoba

Takayoshi Semasa

Yutaka Ueno

Atsushi Tanaka

Hitoshi Kubota

Toshiyuki Takahashi

Makoto Matsumoto

Yoshihiro Ashizaki

Koji Kaneko

Yukiyasu Kawahata

Shuzi Iwata

Yoichi Tenda

Naoto Tanabe

Syuzi Iwata

Ryoichi Ohnishi

Taich Nagiya

Junichi Sadamatsu

Akira Kotani

MULTIPLE QUALITY DATA CREATION ENCODER, MULTIPLE QUALITY DATA CREATION DECODER, MULTIPLE QUANTITY DATA ENCODING DECODING SYSTEM, MULTIPLE QUALITY DATA CREATION ENCODING METHOD, MULTIPLE QUALITY DATA CREATION DECODING METHOD, AND MULTIPLE QUALITY DATA CREATION ENCODING/DECODING METHOD

Encoding efficiency is enhanced by actively combining a plurality of encoding methods. A picture element memory receives and stores picture elements within a predetermined range. A mode determinator selects an encoding mode based upon a reference picture element. A first encoding section and a second encoding section predicts the value of the encoded picture element, determines whether the prediction is correct, and then encodes the value of the encoding picture element based on the determination result and outputs a codeword for the encoding picture element. An encoding controller selectively operates the first encoding section and the second encoding section based upon one of the specific encoding modes and the other encoding mode other than the specific encoding mode selected by the mode determinator.

Encoding apparatus, decoding apparatus, encoding method, and decoding method

By combining a plurality of encoding methods actively, an encoding efficiency is enhanced. The first encoder encodes a result of determination whether a prediction error is zero or not. The second encoder encodes the prediction error unless the prediction error is zero. The third encoder encodes the prediction error regardless of whether the prediction error is zero or not. The mode determinator determines the encoding mode, and the encoding controller selectively operates the first encoder, the second encoder, and the third encoder according to the encoding mode determined.

Encoding apparatus, decoding apparatus, encoding method and decoding method

In an adaptive probability estimation method, an index referring to coding parameters is determined according to occurrence probabilities of symbols from estimated occurrence counts of symbols, thresholds for probability values that determine the probability intervals corresponding to the indexes are set to values that are examined with small operational load, and an index referring to the corresponding occurrence probability is selected without division, using the probability intervals determined by the thresholds for probability values.

Encoding, decoding, and probability estimation method

The present invention aims to reduce the code length and time for flushing the code. An encoding apparatus includes a data memory storing information source data, a learning memory storing learning data relating the encoding data, a probability estimation table for outputting an encoding parameter indicated by the learning data, and an encoder outputting the code by implementing an arithmetic encoding based on the encoding data and the encoding parameter. In the above encoding apparatus, according to the present invention, a synchronization detector is provided measuring one of inputting the information source data and outputting the code at a predetermined interval. Further, the encoding apparatus includes a boundary detector detecting a carry boundary value within the effective region at predetermined interval and instructing to truncate a part of the effective region based on the detection result. The encoder truncates one of equally divided upper and lower partial regions of the effective region indicated by the carry detector and updates the effective region.

Encoding apparatus, decoding apparatus, encoding/decoding apparatus, encoding method and decoding method

A prediction value is previously set in an MPS table corresponding to a state number, a state number for an encoding pixel is obtained from a STATE table, the prediction value is determined based on the MPS table using the state number, a pixel-to-symbol converter compares the prediction value and the encoding pixel to obtain a symbol, and an arithmetic encoder obtains an LPS interval from an LSZ table using the state number for the encoding pixel, and the arithmetic encoder implements encoding based on the symbol and the LPS interval.

Coding method, decoding method, coding device and decoding device

An image data transmission system includes mobile transceivers having memories storing image data that is organized in sequential blocks. The mobile transceivers sequentially pass by a stationary transceiver and pause proximate the stationary transceiver. While pausing, a mobile transceiver transmits a block of the image data to the stationary transceiver, which receives and stores the transmitted data. Data transmission is interrupted by movement of the formerly pausing mobile transceiver. The stationary transceiver transmits a pointer signal to a paused mobile transceiver indicating which blocks of image data have been stored in the stationary transceiver so that the mobile transceivers transmit the blocks sequentially until all blocks have been received and stored by the stationary transceiver. The apparatus may be employed in a mass transit system, such as a subway or commuter train, in which the mobile transceivers are mounted in train cars and the stationary transceiver is located at a station. The image data may be used to illuminate electronic displays in the station each time all of the blocks of data have been transmitted to and stored in the stationary transceiver. Thus, the vehicles containing the mobile transceivers function as a transmission line and can provide continually updated data for news and advertisement displays.

Image data transmission system and method

An adaptive coding method is comprised of: a fourth step (508), (510) for calculating an occurrence frequency of either the more probable symbol (MPS) or the less probable symbol (LPS) with respective to the entered input; a fifth step (511) for comparing an occurrence time accumulated value calculated as the occurrence frequency at the fourth step with a preselected value (threshold value), and for reducing the occurrence time accumulated value by 1/2 in the case that the occurrence time accumulated value reaches the preselected value (threshold value); and a sixth step (513) for defining the more probable symbol (MPS) and the less probable symbol (LPS) in correspondence with a predetermined region on a numerical line with respect to the data signal to thereby output coordinate values on the numerical line as a corded word.

Adaptive coding method

An image memory outputs a target encoding pixel and a plurality of reference pixels in the vicinity thereof. A boundary mode determining unit determines a maximum value and a minimum value of the reference pixels, determines an average value of the maximum value and the minimum value, compares the respective reference pixel values with the average value, detects a boundary in the target encoding pixel and the reference pixels based on comparison results, and detects a pixel distribution state of the reference pixels based on the detected boundary. An adaptive predictor calculates a prediction value by performing a calculation based on a function corresponding to the pixel distribution state and the reference pixels. A prediction difference calculating unit determines a difference value between the prediction value and a value of the target encoding pixel. A prediction coincidence determining unit compares the prediction value and the target encoding pixel value, and outputs a comparison result as a binary signal. A context generator generates a context based on the pixel distribution state and the difference value of the prediction difference calculating unit. An arithmetic encoder encodes the binary signal based on the context thus generated.

Method and apparatus for encoding and decoding an image

This invention relates to a coding system and the coding method in encoding information source symbols of an image. When the total number of original information source symbols cannot be known at the decoding site just from the encoded symbols, it is an object to finish the decoding process correctly and decode the symbols equal to the number of original information source symbols. At an encoding site, the total number of information source unit composed of a finite number of information source symbols is placed at the tail of code at the completion of encoding process. For example, at the encoding site, the number of horizontal pels of an image are transmitted in advance as an information source unit and the total number of lines are placed at the tail of code at the completion of encoding process. At the decoding site, the number of decoded lines is counted and decoded up to the number of lines placed at the tail of code. As a result, it is possible to judge the end of information source symbols without missing the total number.

Coding system

A coding system comprises the comparing circuit which compares a magnitude of the range on the number line which is allocated to the most probability symbol with a magnitude of the fixed range on the number line which is allocated to the Less Probability Symbol. If the range allocated to the MPS is smaller than that to the LPS, and when the symbol is the MPS, the range allocated to the LPS is generated. If the range allocated to the MPS is smaller than that to the LPS, and when the symbol is the LPS, the range allocated to the MPS is generated. By the system, a coding efficiency is improved especially when a probability of occurrence of LPS (Less Probability Symbol) is approximate to 1/2.

Encoding and decoding devices which are capable of increasing the encoding and decoding speed. In arithmetic encoding, there is a possibility of encoding with high efficiency which is very close to the entropy of the information source, but the encoding and decoding time is generally longer than that in another encoding systems such as an MMR encoding system. For example, in a standard facsimile equipment, about 1.3 sec is required for encoding the picture information in an A4-size copy. In prediction encoding, a memory for storing the past reference symbols and the predicted values therefor is necessary for prediction. Since the memory capacity is generally large, a large-capacity RAM is used. The encoding time is therefore greatly dependent on the access speed of the RAM. In the present invention, a high-speed register for storing the predicted value for a special symbol pattern is provided separately from the RAM so that the predicted value of the special symbol pattern is read from this register, thereby enabling high-speed encoding.

Encoding and decoding devices with predictor and detector

Although data is transmitted with efficiency by an arithmetic encoding system, the number of carry control signals increases in proportion to the number of consecutive bits '1' s or bytes X`FF` s in a conventional system. In the present invention, an arithmetic encoder 302 `detects the possibility of a carry generated during arithmetic coding operation being propagated beyond at least a predetermined number of consecutive bytes X`FF` s in a supplied arithmetic code 315. When the propagation of the carry is impossible, a carry control signal is inserted into the first 2 bits of the byte other than X`FF` which occurs immediately after the consecutive bytes X`FF` s so as to transmit the presence or absence of a carry. An arithmetic decoder 303 detects the continuation of at least a predetermined number of bytes X`FF` s in the arithmetic code 315, and arithmetically decodes an output value YN316 on the basis of the predicted value MPS317 of the occurrence probability of the output value YN316 to be encoded and the region width Qe of the complementary predicted value LPS. Since the number of total bits of the inserted carry control signals is reduced by this 'one-time 2-bits insertion system', the total number of transmitted code bits is also reduced.

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Tokyo, Japan

Fumitaka Ono