Image processing apparatus, method and storage medium

• US 7,139,419 B2
• Filed: 06/02/2004
• Issued: 11/21/2006
• Est. Priority Date: 03/19/1999
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Shinbata, Hiroyuki
• Primary Examiner(s): COUSO, YON JUNG
• Application Number:
  US10/857,855
• Publication Number:
  US 20040223658A1
• Time in Patent Office: 902 Days
• Field of Search: 382/132, 382/128, 382/131, 382/168, 382/171, 382/172, 382/282, 250/580, 250/581, 250/582, 250/584, 250/200, 250/206, 250/206.1, 250/206.2, 250/472.1, 250/473.1, 378/4, 378/9, 378/11, 378/12, 378/16, 378/19, 378/20
• US Class Current: 382/132
• CPC Class Codes: A61B 6/50 specially adapted for specific body parts; specially adapted for specific clinical applications
• CPC Class Codes: G06T 2207/10116 X-ray image
• CPC Class Codes: G06T 2207/20008 Globally adaptive
• CPC Class Codes: G06T 2207/20012 Locally adaptive
• CPC Class Codes: G06T 2207/20132 Image cropping
• CPC Class Codes: G06T 2207/30061 Lung
• CPC Class Codes: G06T 5/40 using histogram techniques
• CPC Class Codes: G06T 5/92 based on global image properties
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/136 involving thresholding

Abstract

An image processing apparatus which can always accurately extract, from a photographed image, an optimum feature quantity to be used for image processing is provided. In the apparatus, a limitation unit limits a predetermined area to extract the feature quantity in a lung area of an image (lung image obtained by radiographing). For example, as the predetermined area, the limitation unit limits an area obtained by dividing the lung area in a predetermined ratio, an area extending from ¼ to ½ from a head side of a maximum-length vertical axis of the lung area, or an area within a predetermined-length range from the upside of the lung area. An extraction unit extracts a feature quantity (maximum pixel value) from the predetermined area.

Claims

1. An image processing apparatus for processing an image of an object, comprising:

an extracting unit adapted to extract from the processed image a first area wherein a sensor detects an X-ray which does not pass through the object, and an area of a certain width which is in contact with the first area, wherein said area of a certain width is included in a second area where the sensor detects an X-ray passing through the object in an image output from the sensor; and

an image processing unit adapted to process the image except for a part of the image in the first area and said area of a certain width which is in contact with the first area.

2. An image processing apparatus according to claim 1, wherein said extracting unit extracts said area of a certain width which is in contact with the first area by extracting a pixel within a certain distance from a pixel in the first area.

3. An image processing apparatus according to claim 1,

wherein said image processing unit has a calculating circuit for calculating a feature quantity based on the image except for a part of the image in the first area and said area of a certain width which is in contact with the first area, and said image processing apparatus further comprises a gradation conversion unit adapted to perform gradation conversion of the image using a gradation conversion curve based on the feature quantity.

4. An image processing apparatus according to claim 3, further comprising a calculating unit adapted to calculate a superficial content of an area of the object.

5. An image processing apparatus according to claim 1, further comprising:

an X-ray generation circuit for radiating X-rays;

a two-dimensional X-ray sensor for obtaining, as the image, the X-rays penetrating the objects,

wherein the sensor is a two-dimensional X-ray sensor.

6. An image processing method for processing an image of an object, comprising:

an extracting step of extracting from the processed image a first area wherein a sensor detects an X-ray which does not pass through the object, and an area of a certain width which is in contact with the first area, wherein said area of a certain width is included in a second area where the sensor detects an X-ray passing through the object in an image output from the sensor; and

an image processing step of processing the image except for a part of the image in the first area and said area of a certain width which is in contact with the first area.

8. An image processing method according to claim 6, wherein said extracting step extracts said area of a certain width which is in contact with the first area by extracting a pixel within a certain distance from a pixel in the first area.

7. A computer-readable storage medium which stores a program to achieve an image processing method for processing an image of an object, comprising:

an extracting step of extracting from the processed image a first area wherein a sensor detects an X-ray which does not pass through the object, and an area of a certain width which is in contact with the first area, wherein said area of a certain width is included in a second area where the sensor detects an X-ray passing through the object in an image output from the sensor; and

an image processing step of processing the image except for a part of the image in the first area and said area of a certain width which is in contact with the first area.

9. A computer-readable storage medium according to claim 7, wherein said extracting step extracts said area of a certain width which is in contact with the first area by extracting a pixel within a certain distance from a pixel in the first area.