Canon Kabushiki Kaisha

Shigeo Kato

Yasuhiko Yasuda

Akihiro Katayama

Tetsuo Hasegawa

Hidefumi Ohsawa

Hirokazu Uchio

Hidefumi Osawa

Yoshihiro Nishikawa

Yoshio Takasu

Takeshi Miyashita

This invention relates to an image processing apparatus having a function of encoding or decoding image data and discloses a technique for extracting an image feature, especially a thin image portion of a specific color of an image, and for encoding the thin image portion with high efficiency to minimize degradation of image quality by selecting an appropriate encoding method.

Color image encoding method and apparatus

There is provided an image encoding method in a facsimile apparatus or an image filing apparatus as an image communication apparatus. In this method, a color image signal which is expressed by a plurality of color component signals to be encoded is input, the input color image signal is converted into a bit stream signal, and the bit stream signal is encoded by prediction encoding. A parameter for the prediction encoding is changed in accordance with the color image signal to be encoded. The encoding operation is executed adaptively to the color image signal to be encoded. By virtue of bit stream converting the binary color signal, efficient encoding using the color correlation can be executed and an increase in data amount is prevented. By encoding the bit stream signal using a dynamic arithmetic code, a binary color image can be efficiently encoded.

Image encoding method

Apparatus and method for decoding differently encoded multi-level and

The invention relates to an image processing apparatus having the function to encode or decode image data and discloses a technique in which an optimum encoding method is selected in accordance with the characteristics of an image and a high efficient encoding with little deterioration in image is executed.

Method and apparatus for encoding or decoding an image in accordance

Method and apparatus for encoding and decoding color images

In an image encoding method in which a pixel of interest is predicted with reference to a plurality of pixels near the pixel of interest to be encoded, and encoding is performed on the basis of coincidence/noncoincidence between the predicted pixel and the pixel of interest, a parameter for predicting a pixel is changed on the basis of a rate of coincidence/noncoincidence of the predicted pixel and the pixel of interest.

There is provided an image encoding method in a facsimile apparatus or an image filing apparatus as an image communication apparatus. In this method, a color image signal which is expressed by a plurality of color component signals to be encoded is input, the input color image signal is converted into a bit stream signal, and the bit stream signal is encoded by the prediction encoding. A parameter for the prediction encoding is changed in accordance with the color image signal to be encoded. The encoding operation is executed adaptively to the color image signal to be encoded. By bit stream converting the binary color signal, the efficient encoding using the color correlation can be executed and an increase in data amount is prevented. By encoding the bit stream signal by using a dynamic arithmetic code, a binary color image can be efficiently encoded.

Image encoding method and apparatus providing variable length bit stream

An image encoding apparatus includes a smoothing circuit for smoothing a binary image to be encoded, a binary-encoding circuit for binary-encoding the image smoothed by the smoothing circuit, a sampling circuit for sub-sampling the image binary-encoded by the binary-encoding circuit, and an encoding circuit for encoding the binary image sub-sampled by the sampling circuit. A degree of smoothness of an image by the smoothing circuit and a threshold value for a binary-encoding operation of the binary-encoding circuit can be varied.

Image encoding apparatus

An improved dry toner for developing latent images is disclosed which comprises essentially a resin and a magnetic powder. The resin includes, as the copolymerization components, at least one monomer selected from the group consisting of styrene and its derivatives and at least one monomer selected from the group consisting of maleic acid and its derivatives.

Process of developing latent electrostatic image using dry magnetic

A pressure fixable capsule toner comprises a core material containing a pressure fixable component and an outer shell layer covering the core material and containing a cyclized rubber.

Pressure fixable capsule toner

A pressure fixable capsule toner encapsulated with an insulating material is featured by a main particle size located within a range from 5 to 25.mu., by a particle size distribution that at least 70% in number of the toner particles are within a size range of .+-.3.mu. of the main particle size, and by a relationship 0.02.ltoreq.(a-b)/b.ltoreq.0.4 wherein a and b respectively stand for the main particle size of the capsule toner and core material in microns.

Growing community of inventors

Saitama, Japan

Shigeo Kato