Method and recording medium for separating and composing background and character image data

• US 5,761,339 A
• Filed: 11/28/1995
• Issued: 06/02/1998
• Est. Priority Date: 11/29/1994
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamamoto, Tatsuya, Honda, Koichi, Hamada, Nagaharu, Ikeshoji, Nobuo, Yamakawa, Hiromi, Kamiuchi, Toshiro
• Primary Examiner(s): VU, KIM Y
• Application Number:
  US08/563,533
• Time in Patent Office: 917 Days
• Field of Search: 358/448, 358/461-464
• US Class Current: 382/176
• CPC Class Codes: H04N 1/38 Circuits or arrangements for blanking or otherwise eliminating unwanted parts of pictures H04N1/387 takes precedence
• CPC Class Codes: H04N 1/58 Edge or detail enhancement; Noise or error suppression, e.g. colour misregistration correction H04N1/62 takes precedence

Abstract

An image processing method for automatically executing operation steps of repairing a defect of an image of a document which is read by a scanner and changing a background image in a short time and a recording medium for storing them. An image processing method comprising:

(a) A step of separating background image data from said image data by processing by a maximum filter for comparing the brightness of each pixel constituting said image data with the brightness of peripheral pixels and replacing it with the maximum brightness; and

(b) a step of separating character and figure image data by subtracting the background image data obtained by the above step in (a) from the above image data.

Claims

1. An image processing method for processing image data which is obtained by reading a document in which a character and figure drawing is drawn on a background drawing by a scanner, comprising at least the following steps of:

(a) separating background image data from said image data by processing a maximum filter for comparing the brightness of each pixel constituting said image data with the brightness of peripheral pixels and replacing it with the maximum brightness; and

(b) separating character and figure image data by subtracting said background image data from said image data.

2. A recording medium for storing a program of the image processing method stated in claim 1.

3. An image processing method for composing image data different from said background image data as background image data and said character and figure image data stated in claim 1.

4. An image processing method for processing image data which is obtained by reading a document in which a character and figure drawing is drawn on a background drawing by a scanner, comprising at least the following steps of:

(a) decomposing said image data to data of each color of yellow, magenta, cyan, and black;

(b) separating character and figure image data from said image data using the data of at least one color which is obtained by said step of decomposing said image data to data of each color; and

(c) separating background image data by subtracting said character and figure image data from said image data.

5. A recording medium for storing a program of the image processing method stated in claim 4.

6. An image processing method for processing image data which is obtained by reading a document in which a character and figure drawing is drawn on a background drawing by a scanner, comprising at least the following steps of:

(a) separating background image data from said image data by processing a maximum filter for comparing the brightness of each pixel constituting said image data with the brightness of peripheral pixels and replacing it with the maximum brightness;

(b) separating character and figure image data by subtracting said background image data from said image data; and

(c) composing said background image data and said character and figure image data which are separated by said steps.

7. A recording medium for storing a program of the image processing method stated in claim 6.

8. An image processing method for processing image data which is obtained by reading a document in which a character and figure drawing is drawn on a background drawing by a scanner, comprising at least the following steps of:

(a) decomposing said image data to data of each color of yellow, magenta, cyan, and black;

(b) separating character and figure image data from said image data using the data of at least one color which is obtained by said step of decomposing said image data to data of each color;

(c) separating background image data by subtracting said character and figure image data from said image data; and

(d) composing said background image data and said character and figure image data which are separated by said steps.

9. An image processing method for processing image data which is obtained by reading a document in which a character and figure drawing is drawn on a background drawing by a scanner, comprising at least the following steps of:

(a) separating background image data from said image data by processing a maximum filter for comparing the brightness of each pixel constituting said image data with the brightness of peripheral pixels and replacing it with the maximum brightness;

(b) separating character and figure image data by subtracting said background image data from said image data; and

(c) composing said image data of said document which is read and obtained by said scanner and said background image data and said character and figure image data which are separated by said steps.