Image processing apparatus, method and storage medium

• US 20040223658A1
• Filed: 06/02/2004
• Published: 11/11/2004
• Est. Priority Date: 03/19/1999
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ikeda, Tatsuji, Shinbata, Hiroyuki
• Granted Patent: US 7,139,419 B2
• Time in Patent Office: Days
• US Class Current: 382/254
• 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

1-24_cancelled_. -24.(cancelled)

25. An image processing apparatus comprising:

first extracting means for extracting a direct line area (transparent area) from an image; and

object extracting means for extracting an area of an object from the image,

wherein said object extracting means extracts the object from the image on the basis of the direct line area extracted by said first extracting means and an area of a certain width being in contact with the extracted direct line area.

26. An image processing apparatus according to claim 25, wherein said first extracting means extracts an area of a certain pixel range as the direct line area.

27. An image processing apparatus according to claim 26, wherein the certain pixel range is a range of a value determined based on a maximum value of the image.

28. An image processing apparatus according to claim 25, further comprising:

calculating means for calculating a feature quantity from the area of the object; and

gradation conversion means for determining a shape of a gradation conversion curve using, as a parameter, the feature quantity, and performing gradation conversion of the image using the gradation conversion curve.

29. An image processing apparatus according to claim 28, wherein said calculating means calculates a superficial content of the object area.

30. An apparatus according to claim 25, 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 object.

31. An apparatus according to claim 25, further comprising radiation field recognition means for extracting a radiation field,

wherein said object extracting means extracts the object from an area of the radiation field.

32. An apparatus according to claim 25, further comprising calculation means for calculating the certain width.

33. An image processing method comprising:

a first extracting step, of extracting a direct line area (transparent area) from an image; and

an object extracting step, of extracting an area of an object from the image,

wherein said object extracting step extracts the object from the image on the basis of the direct line area extracted in said first extracting step and an area of a certain width being in contact with the extracted direct line area.

34. A computer-readable storage medium which stores a program to achieve an image processing method comprising:

a first extracting step, of extracting a direct line area (transparent area) from an image; and

an object extracting step, of extracting an area of an object from the image,

wherein said object extracting step extracts the object from the image on the basis of the direct line area extracted in said first extracting step and an area of a certain width being in contact with the extracted direct line area.