Measuring of feature for photo interpretation

• US 4,382,678 A
• Filed: 06/29/1981
• Issued: 05/10/1983
• Est. Priority Date: 06/29/1981
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Secretary Of The Army (Government of the United States of America)
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Mueller, Walter H., Thompson, Henry A., Kottman, Clifford, Phebus, Robert E.
• Primary Examiner(s): Punter, William H.
• Application Number:
  US06/278,263
• Time in Patent Office: 680 Days
• Field of Search: 356/150, 356/372, 356/397, 33/1 A, 33/20 D
• US Class Current: 356/150
• CPC Class Codes: G01C 11/04 Interpretation of pictures

Abstract

A method and apparatus is disclosed for determining the height, width, leh and orientation of an object from the feature image of the object found on oblique panoramic aerial photography. A magnifying eyepiece is provided with a calibrated reticle for measuring the dimensions of the feature image. The eyepiece also has a reference mark and indicia about the eyepiece for measuring the orientation from true north of the longitudinal axis of the feature image. The actual measurements of the object are quickly determined from the measurements of the feature image using a suitably programmed calculator supplied with the photograph and camera parameters.

Claims

1. A method for determining the actual dimensions and orientation of a feature directly from oblique panoramic aerial photography using an eyepiece having a reticle divided into a scale having small increments, the eyepiece including indicia located on the exterior of the eyepiece which indicia is adjustably secured relative to the eyepiece and divided into increments of a circle and a reference mark secured adjacent the indicia, comprising the steps of:

viewing the photography through the magnifying eyepiece;

adjusting the indicia and reference mark to align with one of the photograph axes and securing the indicia to the eyepiece;

scanning the photograph to locate the feature to be measured;

measuring the height, width, and length of the feature using the scale of the reticle;

measuring the orientation of the feature by aligning the scale along the longest axis of the feature and reading the indicia adjacent the reference mark; and

calculating the actual height, width, length and orientation of the feature using the measurements obtained along with the camera and photograph parameters.

2. A method as claimed in claim 1 further including the step of:

programming a computer to perform the calculations of height, width, length and orientation.

3. A method as claimed in claim 2 further including the step of printing the measurements of height, width, length and orientation obtained from the computer onto paper which acts as a permanent record.

4. A method as claimed in claim 1 further including the step of initially calibrating the scale of the reticle.

5. An eyepiece for a microscope used to locate and measure features in oblique panoramic aerial photography comprising:

an elongate eyepiece tube mounted for rotation in the microscope;

a glass reticle with a numbered scale located in said eyepiece tube which is used to measure the height, width and length of the feature image of interest;

indicia located about said elongate eyepiece tube and divided into increments of a circle; and

a reference marke mounted on said eyepiece so as to be independently located with respect to said eyepiece tube adjacent said indicia, said reference mark being used to measure the orientation of the feature image in relation to an axis of the photograph such that these measurements, along with the photograph and camera parameters, are used to calculate the actual dimensions and orientation from true north of the feature.

6. An eyepiece device as claimed in claim 5, further comprising an adjustable drum mounted rotatably about said eyepiece tube, said drum including said indicia and being held against rotation by a set screw so that after initial alignment of said reference mark and drum with a photograph axis and tightening of said set screw, the longitudinal orientation of a feature is determined by the angular rotation of the eyepiece tube in agreement therewith as measured by said drum.

7. An eyepiece as claimed in claim 5, further comprising a ring located independently about said elongate eyepiece tube.

8. An eyepiece device as claimed in claim 7, wherein said reference mark is located on a clear plastic shield attached to said ring and which extends over said dial drum.

9. An eyepiece as claimed in claim 5, wherein the numbered scale of said reticle is calibrated into increments of thousandths of an inch at the final plane and said indicia is divided into two-degree increments.

10. An eyepiece as claimed in claim 5, further including a collar which is threadably received in said elongate eyepiece tube for holding said reticle in place.