Image-processing apparatus, image-processing method and recording medium

• US 7,545,538 B2
• Filed: 12/22/2005
• Issued: 06/09/2009
• Est. Priority Date: 09/27/2000
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Ishii, Rie, Namizuka, Yoshiyuki
• Primary Examiner(s): Grant, II; Jerome
• Application Number:
  US11/313,953
• Publication Number:
  US 20060098227A1
• Time in Patent Office: 1,265 Days
• Field of Search: 358/1.16, 358/1.2, 358/3.1, 358/3.23, 358/521, 358/522, 358/530, 358/539, 399/49, 399/303, 347/252, 382/251
• US Class Current: 358/3.1
• CPC Class Codes: H04N 1/40 Picture signal circuits H04N1/387 takes precedence

Abstract

In an image-processing apparatus, a digital image signal is stored in a memory, and a memory access control part entirely manages all accesses to the memory with respect to the digital image signal. An image processing part converts the digital image signal stored in the memory into an output image signal to be supplied to an imaging unit outputting a visible image based on the output image signal so that a pixel density of the output image signal is higher than a pixel density of the digital image signal read from the memory and an amount of the output image signal is less than an amount of the digital image signal stored in the memory. Accordingly, the central controlled memory is shared by a plurality of functions so as to effectively use the memory, and a high-quality image can be produced by carrying out a density conversion so as to match the pixel density.

Claims

1. An image-processing apparatus comprising:

a memory storing a digital image signal;

an image processing part converting the digital image signal stored in said memory into an output image signal so that a pixel density of the output image signal is higher than a pixel density of the digital image signal read from said memory; and

a programmable operation processor processing the digital image signal so as to reduce a number of quantization steps of the digital image signal and store the digital image signal having a reduced number of quantization steps in said memory.

2. An image-processing apparatus comprising:

a memory storing a digital image signal;

an image processing part converting the digital image signal stored in said memory into an output image signal so that a pixel density of the output image signal is higher than a pixel density of the digital image signal read from said memory; and

a memory access control part that arranges pixels of the output image signal in a square area while preventing generation of an isolated single pixel of black or white when converting the digital image data into the output image data.

3. An image-processing apparatus comprising:

a memory storing a digital image signal;

an image processing part converting the digital image signal stored in said memory into an output image signal so that a pixel density of the output image signal is higher than a pixel density of the digital image signal read from said memory;

a memory access control part that includes a pixel density conversion part converting the digital image signal by using said memory; and

said image processing part includes an edge smoothing part smoothing an edge of black pixels and white pixels,

wherein said edge smoothing part is controlled, separately from said pixel density conversion part, by a write-in control performed by an imaging unit outputting a visible image based on the output image signal.

4. An image-processing apparatus comprising:

a memory storing a digital image signal; and

an image processing part converting the digital image signal stored in said memory into an output image signal so that pixel densities of the output image signal in a main scanning direction and a subscanning direction are higher than pixel densities of the digital image signal in the main scanning direction and the subscanning direction read from said memory,

wherein;

the output image signal is transmitted from said memory to an imaging unit in a form of code data; and

said imaging unit converts the code data into pixel data so as to perform an image output under a write write-in control of said imaging unit.

5. The image-processing unit as claimed in claim 4, wherein translation of the code data from said memory to said imaging unit is performed in synchronization with a signal indicating a write-in line of the code data.

6. An image-processing method comprising the steps of:

storing a digital image signal in a memory;

reading the digital image signal from said memory;

converting the read image data into an output image data having pixel densities in a main scanning direction and a subscanning direction higher than pixel densities of the read image data in the main scanning direction and the subscanning direction; and

outputting the output image data to an imaging unit forming a visible image based on the output image data,

wherein a number of quantization steps of the digital image signal is reduced.

7. A program, stored in a computer-usable medium, for causing an image-processing apparatus to perform an image-processing method, the image-processing method comprising:

storing a digital image signal in a memory;

reading the digital image signal from said memory;

converting the read image data into an output image data having pixel densities in a main scanning direction and a subscanning direction higher than pixel densities of the read image data in the main scanning direction and the subscanning direction; and

outputting the output image data to an imaging unit forming a visible image based on the output image data,

wherein a number of quantization steps of the digital image signal is reduced.

8. A processor readable medium storing a program for causing an image-processing apparatus to perform an image-processing method, the image-processing method comprising:

storing a digital image signal in a memory;

reading the digital image signal from said memory;

converting the read image data into an output image data having pixel densities in a main scanning direction and a subscanning direction higher than pixel densities of the read image data in the main scanning direction and the subscanning direction; and

outputting the output image data to an imaging unit forming a visible image based on the output image data,

wherein a number of quantization steps of the digital image signal is reduced.