Image forming apparatus, image processing method and storage medium storing program for image processing

Abstract

An image forming apparatus that forms an image based on image data input thereto, includes a mode switching unit that switches between a save mode in which an amount of consumption of imaging material is reduced and a normal operation mode in which an amount of consumption of imaging material is not changed, a gain processing unit that decreases a gain of a specific frequency component, based on a spatial frequency characteristic of an input image, during operation under the save mode, and an output unit that outputs the input image under the normal operation mode or an image processed by the gain processing unit under the save mode according to the selection made by the mode switching unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein:

FIG. 1 illustrates an image forming apparatus which is an exemplary embodiment of the present invention;

FIG. 2 shows a functional structure of a controller in this exemplary embodiment;

FIG. 3 shows an example of a spatial frequency characteristic graph of an image;

FIGS. 4A and 4B illustrate examples of sets of coefficients for a 3×3 digital filter; and

FIG. 5 is a flowchart illustrating a flow of image output operation of the image forming apparatus to which this exemplary embodiment is applied.

Claims

1. An image forming apparatus that forms an image based on image data input thereto, comprising: a mode switching unit that switches between a save mode in which an amount of consumption of imaging material is reduced and a normal operation mode in which an amount of consumption of imaging material is not changed;a gain processing unit that decreases a gain of a specific frequency component, based on a spatial frequency characteristic of an input image, during operation under the save mode; andan output unit that outputs the input image under the normal operation mode or an image processed by the gain processing unit under the save mode according to the selection made by the mode switching unit.

2. The image forming apparatus according to claim 1, wherein the gain includes a modulation transfer function.

3. The image forming apparatus according to claim 1, wherein the gain processing unit decreases a gain of a DC component of spatial frequency in the input image.

4. The image forming apparatus according to claim 1, wherein the mode switching unit accepts a mode selection made by a user and carries out operation mode switchover according to the selection.

5. The image forming apparatus according to claim 4, further comprising a user interface via which the mode selection made by the user is accepted.

6. The image forming apparatus according to claim 1, further comprising a text/image separation unit that makes a distinction between text and image for an object in the input image, wherein the gain processing unit executes processing on the object recognized as an image.

7. An image forming apparatus that forms an image based on image data input thereto, comprising: an analysis unit that analyzes a spatial frequency characteristic of an input image;a gain processing unit that performs processing on a gain of a specific frequency component either to decrease the gain or to leave the gain unchanged, based on a result of analysis of the spatial frequency characteristic; andan output unit that outputs an image based on the input image processed by the gain processing unit.

8. The image forming apparatus according to claim 7, wherein the gain includes a modulation transfer function.

9. The image forming apparatus according to claim 7, wherein the gain processing unit performs processing on a gain of a DC component of spatial frequency in the input image.

10. The image forming apparatus according to claim 7, further comprising a mode switching unit that selects whether to cause the gain processing unit to decrease the gain or to leave the gain unchanged, wherein the output unit outputs an image based on the input image processed by the gain processing unit, according to selection made by the mode switching unit.

11. The image forming apparatus according to claim 7, further comprising a text/image separation unit that makes a distinction between text and image for an object in the input image, wherein the gain processing unit executes processing on the object recognized as an image.

12. An image processing method comprising: analyzing a spatial frequency characteristic of an input image;performing processing on a gain of a specific frequency component either to decrease the gain or to leave the gain unchanged, based on a result of analysis of the spatial frequency characteristic; andoutputting an image based on the input image for which the processing on the gain has been done.

13. The image processing method according to claim 12, further comprising accepting a mode selection by a user and switching between a save mode in which an amount of consumption of imaging material is reduced and a normal operation mode in which an amount of consumption of imaging material is not changed, wherein, only after switching to the save mode, analyzing the spatial frequency characteristic and performing the processing on the gain of a specific frequency component are executed.

14. The image processing method according to claim 12, further comprising making a distinction between text and image for an object in the input image, wherein, for the object recognized as an image, analyzing the spatial frequency characteristic and performing the processing for the gain of a specific frequency component are executed.

15. A storage medium readable by a computer, the storage medium storing a program of instructions executable by the computer to perform a function for image processing, the function comprising: analyzing a spatial frequency characteristic of an input image;performing processing on a gain of a specific frequency component either to decrease the gain or to leave the gain unchanged, based on a result of analysis of the spatial frequency characteristic; andoutputting an image based on the input image for which the processing on the gain has been done.