US 8,712,174 B2Granted

Image processing apparatus and image processing method

AssigneeRicoh Company, Ltd.

InventorNaoto Shiraishi

Life of this patent

Estimating the term…

Loading patent…

Abstract

In an image processing apparatus according to an embodiment, a first prediction value calculating unit calculates a prediction value of the pixel value; a prediction error calculating unit calculates a prediction error between the prediction value and the pixel value of the target pixel; a second storage unit receives the prediction error sequentially from a first terminal and stores therein; a comparing unit compares the prediction error with each of the prediction errors already stored; a search unit, when the prediction error thus received is identical to each of the prediction errors, searches for a data array; a length information generating unit generates length information; an address information generating unit generates address information; a first code data generating unit generates first code data; and a second code data generating unit generates second code data by encoding the pixel value of the target pixel.

Claims4

Dependent claims

An image processing apparatus comprising:

a first storage unit into which each pixel value of a plurality of pixels that constitute image data is written;
a first reading unit that reads a pixel value of a target pixel to be encoded and a pixel value of a surrounding pixel of the target pixel from the first storage unit;
a first prediction value calculating unit that calculates a prediction value of the pixel value of the target pixel based on the pixel value of the surrounding pixel read by the first reading unit;
a prediction error calculating unit that calculates a prediction error that is difference between the prediction value calculated by the first prediction value calculating unit and the pixel value of the target pixel;
a second storage unit configured to,
sequentially receive the prediction error calculated by the prediction error calculating unit from a first terminal as a received prediction error,
store therein the received prediction error consecutively as stored prediction errors, the stored prediction errors being previously received prediction errors, and
transfer the stored prediction errors to a second terminal;
a comparing unit that compares the received prediction error with each of the stored prediction errors;
a search unit that, when the received prediction error is identical to each of the stored prediction errors as a result of comparison made by the comparing unit, searches for a data array that is composed of the stored prediction error that is stored consecutively and that is identical to an input data array composed of the received prediction error that is received sequentially;
a length information generating unit that generates length information indicating a length of the data array searched for by the search unit;
an address information generating unit that generates address information indicating a position in the second storage unit at which start data of the data array searched for by the search unit is stored;
a first code data generating unit that generates first code data obtained by encoding the length information generated by the length information generating unit and the address information generated by the address information generating unit;
and
a second code data generating unit that, when the received prediction error is identical to none of the stored prediction errors as a result of the comparison made by the comparing unit, generates second code data obtained by encoding the pixel value of the target pixel from which the received prediction error is calculated.

12 more elements

An image processing method comprising:

reading a pixel value of a target pixel to be encoded and a pixel value of a surrounding pixel of the target pixel from a first storage unit into which each pixel value of a plurality of pixels that constitute image data is written;
first calculating that includes calculating a prediction value of the pixel value of the target pixel based on the pixel value of the surrounding pixel read at the reading;
second calculating that includes calculating a prediction error that is a difference between the prediction value calculated at the first calculating of a prediction value and the pixel value of the target pixel and sending the calculated prediction error to a second storage unit;
sequentially receiving the calculated prediction error as a received prediction error;
storing, in the second storage unit, the received prediction errors consecutively as stored prediction errors, the stored prediction errors being previously received prediction errors;
comparing the received prediction error with each of the stored prediction errors;
searching for, when the received prediction error is identical to each of the stored prediction errors as a result of comparison at the comparing, a data array that is composed of the stored prediction error that is stored consecutively and that is identical to an input data array composed of the received prediction error that is received sequentially;
generating length information indicating the length of the data array searched for at the searching;
generating address information indicating a position in the second storage unit at which start data of the data array searched for at the searching is stored;
generating first code data obtained by encoding the length information generated at the generating of length information and the address information generated by the address information generating unit;
and
generating, when the received prediction error is identical to none of the stored prediction errors as a result of the comparison at the comparing, second code data obtained by encoding the pixel value of the target pixel in which the received prediction error is calculated.

9 more elements

Dependencies are inferred from the claim text.