Photogrammetric image processing apparatus and method

• US 6,768,813 B1
• Filed: 06/15/2000
• Issued: 07/27/2004
• Est. Priority Date: 06/16/1999
• Status: Expired due to Fees

• Current Assignee: Pentax Corporation (Hoya Corporation)
• Original Assignee: Pentax Corporation (Hoya Corporation)
• Inventors: Nakayama, Toshihiro
• Primary Examiner(s): Mehta, Bhavesh M.
• Assistant Examiner(s): CARTER, AARON W
• Application Number:
  US09/594,035
• Time in Patent Office: 1,503 Days
• Field of Search: 382/154, 382/285, 345/419-427, 356/12-14, 348/578, 348/580
• US Class Current: 382/154
• CPC Class Codes: G01C 11/02 Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures

Abstract

A photogrammetric image processing apparatus and method defining a plurality of pairs of images including a common target as belonging to the same groups (pairs), providing an image display area and drawing area on the screen of the display device, displaying images of a pair 1 on the image display area, calculating a valid mapping range for the pair 1, displaying an area marker showing the valid mapping range on the survey map superimposed in the drawing area, designating corresponding image points on the image of the pair 1 to calculate the three-dimensional coordinates of physical points, and generating a survey map based on the three-dimensional coordinates.

Claims

1. A photogrammetric image processing apparatus that utilizes a group comprising a plurality of images, each image commonly including a target at a predetermined position, that calculates a position of a camera taking each image and an inclination of an optical axis of the camera for each image, that designates a common physical point in each image, calculates three-dimensional coordinates of the physical point, and that generates a survey map based on the three-dimensional coordinates, said photogrammetric image processing apparatus comprising:

an area computing processor that calculates a valid mapping range based on the camera positions and the optical axis inclinations for the plurality of images in the group and that generates an area marker based on the valid mapping range, the valid mapping range enabling designation of the physical point for making the survey map, and

a display processor that displays the area marker on a screen of a display device, the area marker being superimposed on the survey map.

2. The apparatus as set forth in claim 1, wherein said area computing processor calculates ranges of guaranteed precision respectively corresponding to the plurality of images in the group and determines an overlapping area of the ranges of guaranteed precision as the valid mapping range.

3. The apparatus as set forth in claim 2, wherein the ranges of guaranteed precision are respectively recorded as label images comprising pixel values, and the overlapping area is determined based on the pixel values of the label images.

4. The apparatus as set forth in claim 2, wherein each range of guaranteed precision is determined based on the camera position and a predetermined allowable error.

5. The apparatus as set forth in claim 4, wherein the camera comprises an imaging device that converts an optical image into an electronic image, and wherein each range of guaranteed precision is determined based on a resolution power of the imaging device.

6. The apparatus as set forth in claim 4, wherein a magnitude of each range of guaranteed precision changes according to the predetermined allowable error.

7. The apparatus as set forth in claim 6, wherein:

a plan view of a ground surface from perpendicularly above is displayed on the screen as the survey map,

each range of guaranteed precision is determined as an area surrounded by two parallel lines perpendicular to the optical axis of the camera, the two parallel lines being respectively separated from the camera by a near limit of guaranteed precision and a far limit of guaranteed precision, and by two lines defining a horizontal projection of an angle of view on the ground surface,

the near limit of guaranteed precision is a shortest distance between a line defining an intersection of a vertical angle of view of the camera and the ground surfaces, and a vertical line from the camera to the ground surface, and

the far limit of guaranteed precision is a distance from the camera at which a value corresponding to a resolution power of an imaging device of the camera is equal to the predetermined allowable error.

8. The apparatus as set forth in claim 1, further comprising:

a reading processor that reads an image from an image storage medium storing a plurality of images, each image including the target configured to output a displacement amount and a rotational angle, and

an input processor that designates an image point corresponding to the physical point in the area marker in the plurality of images in the group.

9. The apparatus as set forth in claim 8, wherein the group comprises a plurality of groups, each coordinate system of each group is determined based on a reference point provided on the target, the coordinate systems of the plurality of groups are converted to the coordinate system of one group, and the area markers of the plurality of groups are displayed on the same screen.

10. The apparatus as set forth in claim 9, wherein the screen comprises an image display area and a drawing area, said display processor displays the images stored in the image storage medium in the image display area, and said display processor displays the area markers of the plurality of groups and the survey map in the drawing area, the area markers being superimposed on the survey map.

11. The apparatus as set forth in claim 1, wherein the group comprises a plurality of groups, an enclosure indicating a boundary of the valid mapping range is determined as a detailed area marker for each group, and the detailed area marker of one group of the plurality of groups, which is determined to be used for mapping to designate a physical point, is displayed on the screen.

12. The apparatus as set forth in claim 11, wherein when one of the plurality of groups is determined to be used for mapping, a simple area marker, which is different from the detailed area marker, is displayed on the screen in a representation different from a representation of the detailed area marker used for mapping.

13. An The apparatus as set forth in claim 12, wherein

each group includes two images photographed at two different camera positions,

when projections of optical axes of the two camera positions on the ground surface in each group form an intersection, a bisector of an angle at the intersection is determined as a provisional optical axis, and

the simple area marker is defined as a boundary of a trapezoidal area based on a near limit of guaranteed precision and a far limit of guaranteed precision for one camera position, the trapezoidal area including two parallel lines perpendicular to the provisional optical axis and respectively separated by the near limit of guaranteed precision and the far limit of guaranteed precision from the one camera position, the trapezoidal area having the provisional optical axis as an axis of symmetry.

14. The apparatus as set forth in claim 12, wherein

each group includes two images photographed at two different camera positions,

when projections of optical axes at the two camera positions on the ground surface in each group do not intersect and lines along angles of view form an intersection, a bisector of an angle at the intersection is determined as a provisional optical axis, and

the simple area marker is defined as a boundary of a trapezoidal area based on a near limit of guaranteed precision and a far limit of guaranteed precision for one camera position, the trapezoidal area including two parallel lines perpendicular to the provisional optical axis and respectively separated by the near limit of guaranteed precision and the far limit of guaranteed precision from the one camera position, the trapezoidal area having the provisional optical axis as an axis of symmetry.

15. An apparatus as set forth in claim 12, wherein

each group includes a plurality of images photographed at a plurality of camera positions,

a plurality of intersection points among projections of optical axes for the plurality of camera positions on the ground surface are calculated, and

the simple area marker is defined as a boundary of a circular area that has a predetermined radius from a center defined by an arithmetic average of coordinates of the plurality of intersection points.

16. A photogrammetric image processing method that utilizes a group comprising a plurality of images, each image commonly including a target placed at a predetermined position and being configured to output an amount of displacement and rotational angle, that calculates a position of a camera taking each image and an inclination of an optical axis of the camera for each image, that designates a common physical point in each image, that calculates three-dimensional coordinates of the physical point, and that generates a survey map based on the three-dimensional coordinates,

said photogrammetric image processing method comprising:

calculating a valid mapping range based on the camera positions and the optical axis inclinations of the plurality of images in the group;

generating an area marker based on the valid mapping range;

displaying the area marker together with the plurality of images on a screen, the area marker being superimposed on the survey map; and

designating a physical point in the area marker in each of the plurality of images displayed on the screen.

17. A storage medium storing a photogrammetric image processing program that utilizes a group comprising a plurality of images, each image commonly including a target placed at a predetermined position that calculates a position of a camera taking each image and an inclination of an optical axis of the camera for each image, that designates a common physical point in an each image, that calculates three-dimensional coordinates of the physical point, and that generates a survey map based on the three-dimensional coordinates,

said photogrammetric image processing program comprising:

an area maker calculation routine that calculates a valid mapping range, enabling designation of the physical point for making the survey map based on the camera positions and the optical axis inclinations for the plurality of images in the group and that generates an area marker based on the valid mapping range; and

a drawing area display processing routine that displays the area marker on a screen, the area marker being superimposed on the survey map.