Image processing device for correcting skew deviation, image forming apparatus, image processing method for correcting skew deviation, and non-transitory recording medium

Patent metadata

Field	Value
Publication number	US-10148853-B2
Application number	US-201615378401-A
Country	US
Kind code	B2
Filing date	Dec 14, 2016
Priority date	Jan 5, 2016
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

An image processing device includes a writing circuit to write image data to a first memory, a second memory with a capacity of lines, a coordinate generating circuit to generate coordinate information based on inclination information, a deviation calculating circuit to calculate a maximum deviation amount of the image data from the coordinate information, a division number calculating circuit to calculate a division number based on the number of the lines and the deviation amount, an address generating circuit to generate an address for reading each of divided areas of the image data from the first memory, a burst length calculating circuit to calculate a burst length based on the division number and a main scanning width of the image data, and a transferring circuit to read and burst-transfer the image data from the first memory to the second memory based on the address and the burst length.

First claim

The invention claimed is:

1. An image processing device comprising:
a data writing circuit configured to write image data to a first memory;
a second memory having a line memory with a capacity of a plurality of lines to store the image data transferred from the first memory;
a coordinate generating circuit configured to generate coordinate information based on inclination information, the coordinate information including a coordinate in a main scanning direction and a coordinate in a sub-scanning direction that together represent a position of each of pixels of the image data relative to an output medium onto which the image data is to be output, and the inclination information representing an inclination of the image data in the first memory relative to the output medium;
a maximum deviation amount calculating circuit configured to calculate a maximum deviation amount in the sub-scanning direction of the image data from the coordinate information;
a division number calculating circuit configured to calculate a division number for dividing the image data in the main scanning direction, based on the capacity of the second memory and the maximum deviation amount in the sub-scanning direction of the image data;
a read address generating circuit configured to generate a read start address for reading from the first memory each of divided areas of the image data divided by the division number;
a burst length calculating circuit configured to calculate a burst length based on the division number and a width of the image data in the main scanning direction;
a data transferring circuit configured to read the divided areas of the image data from the first memory and burst-transfer the divided areas of the image data to the second memory based on the read start address and the burst length; and
a controller circuit configured to,
read the image data from the second memory in such a manner that the inclination of the image data is corrected, and
output the corrected image data.

2. The image processing device of claim 1 , wherein the coordinate generating circuit generates the coordinate information including the coordinate in the main scanning direction and the coordinate in the sub-scanning direction that together represent at least one of,
the position of each of pixels of the image data relative to the first memory based on coordinates representing an inclination of the image data written to the first memory relative to the first memory, and
the position of each of pixels of the image data relative to the output medium based on coordinates representing an inclination of the image data written to the first memory relative to the output medium.

3. The image processing device of claim 1 , wherein the division number calculating circuit is configured such that the calculating of the division number includes,
generating a calculation result based on the capacity of the second memory and the maximum deviation amount in the sub-scanning direction of the image data, and
adopting the generated calculation result as the calculated division number in response to the generated calculation result being a power of two.

4. An image forming apparatus comprising:
an image reading device configured to read a document to generate first image data, the first image data being image data of the document;
the image processing device of claim 1 to perform image processing on the first image data; and
an image output device configured to form and output an image on an output medium based on the first image data upon which the image processing device performed the image processing.

5. An image processing method comprising:
writing image data to a first memory;
transferring the image data from the first memory to a second memory having a line memory with a capacity of a plurality of lines;
generating coordinate information based on inclination information, the coordinate information including a coordinate in a main scanning direction and a coordinate in a sub-scanning direction that together represent a position of each of pixels of the image data relative to an output medium onto which the image data is to be output, and the inclination information representing an inclination of the image data in the first memory relative to the output medium;
calculating a maximum deviation amount in the sub-scanning direction of the image data from the coordinate information;
calculating a division number for dividing the image data in the main scanning direction, based on the capacity of the second memory and the maximum deviation amount in the sub-scanning direction of the image data;
generating a read start address for reading from the first memory each of divided areas of the image data divided by the division number;
calculating a burst length based on the division number and a width of the image data in the main scanning direction;
reading the divided areas of the image data from the first memory and burst-transferring the divided areas of the image data to the second memory based on the read start address and the burst length;
reading the image data from the second memory in such a manner that the inclination of the image data is corrected; and
outputting the corrected image data.

6. The image processing method of claim 5 , wherein the generating the coordinate information comprises:
generating the coordinate information including the coordinate in the main scanning direction and the coordinate in the sub-scanning direction that together represent at least one of,
the position of each of pixels of the image data relative to the first memory based on coordinates representing an inclination of the image data written to the first memory relative to the first memory, and
the position of each of pixels of the image data relative to the output medium based on coordinates representing an inclination of the image data written to the first memory relative to the output medium.

7. The image processing method of claim 5 , wherein the calculating the division number comprises:
generating a calculation result based on the capacity of the second memory and the maximum deviation amount in the sub-scanning direction of the image data, and
adopting the generated calculation result as the calculated division number in response to the generated calculation result being a power of two.

8. A non-transitory recording medium storing a program for causing a computer to execute an image processing method, the image processing method comprising:
writing image data to a first memory;
transferring the image data from the first memory to a second memory having a line memory with a capacity of a plurality of lines;
generating coordinate information based on inclination information, the coordinate information including a coordinate in a main scanning direction and a coordinate in a sub-scanning direction that together represent a position of each of pixels of the image data relative to an output medium onto which the image data is to be output, and the inclination information representing an inclination of the image data in the first memory relative to the output medium;
calculating a maximum deviation amount in the sub-scanning direction of the image data from the coordinate information;
calculating a division number for dividing the image data in the main scanning direction, based on the capacity of the second memory and the maximum deviation amount in the sub-scanning direction of the image data;
generating a read start address for reading from the first memory each of divided areas of the image data divided by the division number;
calculating a burst length based on the division number and a width of the image data in the main scanning direction;
reading the divided ar

Assignees

• Watanabe Yuuto
• Tanaka Tomonori
• Ohta Naoki
• Iwasaki Mitsutaka
• Ricoh Co Ltd

Inventors

• Watanabe Yuuto
• Tanaka Tomonori
• Ohta Naoki
• Iwasaki Mitsutaka

Classifications

• H04N1/506

  Reproducing the colour component signals picture-sequentially, e.g. with reproducing heads spaced apart from one another in the subscanning direction · CPC title

• H04N1/3878 Primary

  Skew detection or correction · CPC title

• H04N1/00068

  Calculating or estimating · CPC title

• H04N1/2104

  for one or a few pictures · CPC title

• H04N2201/0094

  Multifunctional device, i.e. a device capable of all of reading, reproducing, copying, facsimile transception, file transception · CPC title