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US 7,069,460 B2Granted
Method and apparatus for image processing with an effective line noise correction
AssigneeRicoh Company, Ltd.
InventorSatoshi Ohkawa
Life of this patent
Estimating the term…
Abstract
An image processing apparatus including an image processing circuit, a frequency dispersion circuit, and a timing signal generator. The image processing circuit processes an image signal, and the frequency dispersion circuit performs frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and to generate a frequency dispersion clock signal. The timing signal generator generates a timing signal that controls an operation of the image processing circuit using the frequency dispersion clock signal, in synchronism with the predetermined modulation cycle used for the frequency dispersion.
Claims20
An image processing apparatus, comprising:
- an image processing circuit configured to process an image signal as image reproduction data, said image signal being read by a line image sensor;
- a frequency dispersion circuit configured to perform frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and to generate a frequency dispersion clock signal;
- and
- a timing signal generator configured to generate a timing signal that controls an operation of said image processing circuit using the frequency dispersion clock signal generated by said frequency dispersion circuit, said timing signal generator generating the timing signal in synchronism with the predetermined modulation cycle used for the frequency dispersion relative to the reference clock signal.
1 more element
An image processing apparatus, comprising:
- an image processing circuit configured to process an image signal as image reproduction data, said image signal being read by a line image sensor;
- a frequency dispersion circuit configured to perform a frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and to generate a frequency dispersion clock signal;
- a timing signal generator configured to generate a timing signal that controls an operation of said image processing circuit using the frequency dispersion clock signal generated by said frequency dispersion circuit;
- and
- a noise correction circuit configured to previously obtain correction data for one dispersion cycle, to store the correction data, and to correct for a noise produced relative to an image due to the timing signal using the frequency dispersion clock signal in the predetermined modulation cycle of the frequency dispersion with reference to the stored correction data.
2 more elements
An image processing apparatus, comprising:
- image processing means for processing an image signal as image reproduction data, said image signal being read by a line image sensor;
- frequency dispersing means for performing frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and generating a frequency dispersion clock signal;
- and
- timing signal generating means for generating a timing signal that controls an operation of said image processing means using the frequency dispersion clock signal generated by said frequency dispersing, said timing signal generating means generating the timing signal in synchronism with the predetermined modulation cycle used for the frequency dispersion relative to the reference clock signal.
1 more element
An image processing apparatus, comprising:
- image processing means for processing an image signal as image reproduction data, said image signal being read by a line image sensor;
- frequency dispersing means for performing frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and generating a frequency dispersion clock signal;
- timing signal generating means for generating a timing signal that controls an operation of said image processing means using the frequency dispersion clock signal generated by the frequency dispersing means;
- and
- noise correcting means for previously obtaining correction data for one dispersion cycle, for storing said correction data, and for correcting for a noise produced relative to an image due to the timing signal using the frequency dispersion clock signal in the predetermined modulation cycle of the frequency dispersion with reference to the stored correction data.
2 more elements
A method of image processing, comprising the steps of:
- processing an image signal as image reproduction data, said image signal being read by a line image sensor;
- performing frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle;
- outputting a frequency dispersion clock signal;
- and
- generating a timing signal in synchronism with the predetermined modulation cycle used for the frequency dispersion relative to the reference clock signal, said timing signal controlling operations of said performing and outputting step using the frequency dispersion clock signal generated in said performing step.
2 more elements
A method of image processing, comprising the steps of:
- processing an image signal as image reproduction data, said image signal being read by a line image sensor;
- performing frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle;
- outputting a frequency dispersion clock signal;
- generating a timing signal that controls an operation of said performing and outputting steps using the frequency dispersion clock signal generated by said performing step;
- obtaining previously correction data for one dispersion cycle;
- storing said correction data;
- and
- correcting a noise produced relative to an image due to said timing signal using said frequency dispersion clock signal in the predetermined modulation cycle of said frequency dispersion with reference to said stored correction data.
5 more elements
An image forming apparatus, comprising:
- an image reading mechanism configured to read an image and to generate analog image data;
- an image processing mechanism configured to process the analog image data generated by said image reading mechanism and to output digital image data for an image reproduction, said image processing mechanism including:
- an image processing circuit configured to process an image signal as image reproduction data, said image signal being read by a line image sensor;
- a frequency dispersion circuit configured to perform frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and to generate a frequency dispersion clock signal;
- and
- a timing signal generator configured to generate a timing signal that controls an operation of said image processing circuit using the frequency dispersion clock signal generated by said frequency dispersion circuit, said timing signal generator generating the timing signal in synchronism with the predetermined modulation cycle used for the frequency dispersion relative to the reference clock signal;
- and
- an image reproducing mechanism configured to reproduce said image data for the image reproduction output from said image processing mechanism.
5 more elements
An image forming apparatus, comprising:
- an image reading mechanism configured to read an image and to generate analog image data;
- an image processing mechanism configured to process the analog image data and to output digital image data, said image processing mechanism including:
- an image processing circuit configured to process an image signal as image reproduction data, said image signal being read by a line image sensor;
- a frequency dispersion circuit configured to perform frequency dispersion relative to a reference clock signal by continuously modulating an oscillating frequency of the reference clock signal in a predetermined modulation cycle and to generate a frequency dispersion clock signal;
- a timing signal generator configured to generate a timing signal that controls an operation of said image processing circuit using the frequency dispersion clock signal generated by said frequency dispersion circuit;
- and
- a noise correction circuit configured to previously obtain correction data for one dispersion cycle, to store the correction data, and to correct for a noise produced relative to an image due to the timing signal using the frequency dispersion clock signal in the predetermined modulation cycle of said frequency dispersion with reference to said stored correction data;
- and
- an image reproducing mechanism configured to reproduce said image data for the image reproduction output from said image processing mechanism.
6 more elements
Dependencies are inferred from the claim text.