JP2012193960A - Target distance detection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that, conventionally, an error was incurred in a target dimension by a look-down angle in detecting a target.SOLUTION: A target distance detection apparatus includes an operation display which displays thereon a target image obtained by an image sensor and is capable of identifying a target dimension of a range-finding object from the displayed image, a target dimension table storing therein target dimensions of a plurality of kinds of targets, a target dimension retriever which retrieves the target dimension from the target dimension table on the basis of the kind of the target identified by the operation display, a target dimension converter which outputs a target dimension converted value by converting the target dimension retrieved by the target dimension retriever with a swing angle of the image sensor, a target surface display range calculator which calculates a target surface display range at a position where the target is present within the image outputted from the image sensor from the target dimension converted value, the total number of pixels of the image and the number of longitudinal or lateral pixels occupied by the target, and a distance calculator which calculates a distance to the target from the target surface display range and an angle of view from the image sensor.

Description

  The present invention relates to a target distance detection device that detects a distance to a target based on image information or the like output from one image sensor.

  Currently, various proposals have been made for a method in which an operator specifies a distance measurement target based on an image of a target output from an image sensor and detects the distance of the target. Is well known.

  As an example of such a method, an image target distance measuring device that calculates the number of pixels of the image sensor and the distance from the target dimension detected by the image sensor to the target is known as a prior art (for example, Patent Documents). 1).

  However, in the conventional technology as described above, since the target size differs depending on the angle at which the target is looked down, ambiguity occurs in the distance to the target to be measured, and it is difficult to measure accurately. There are concerns.

  In order to prevent this, it is desirable to estimate the look-down angle when the operator detects the target, and to have a target size table corresponding to various look-down angles. difficult.

Japanese Patent Laying-Open No. 2007-85845 (FIG. 1)

  As described above, in the conventional technology, ambiguity is generated in the target dimension due to the look-down angle when the target is detected. Therefore, a system that accurately measures the distance to the target with one image sensor is still in consideration. Not realized.

  The present invention has been made in order to solve the above-described problems, and provides a target distance detection apparatus capable of measuring a distance with one piece of image sensor information in order to reduce the size, weight, and cost. With the goal.

  A target distance detecting device according to the present invention displays an image of a target of a distance measurement target obtained by an image sensor, and an operation indicator capable of specifying a target dimension of a distance measurement target from the display image, A target dimension table storing target dimensions of one or a plurality of types of targets, a target dimension searcher for searching a target dimension from the target dimension table based on a target type specified by the operation indicator, and the target The target dimension searched by the dimension searcher is converted by the image sensor swing angle and the target dimension converted value is output, and the target dimension converted value is output from the image sensor. From the total number of pixels of the image and the number of vertical or horizontal pixels occupied by the target, a target plane display range at a position where the target exists in the image displayed on the operation display Comprising a target surface display range calculator for output, and a distance calculator for calculating a distance to the target from the field angle from the image sensor and the target surface display range.

  According to the present invention, the distance to the target can be measured by converting the target dimension according to the swing angle of the image sensor by using one image sensor information, and the size, weight, cost, and accuracy can be reduced. I can plan.

It is a block diagram which shows the structure of the target distance detection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the specific example of the target distance detection which concerns on Embodiment 1 of this invention. It is an example of the target dimension table which concerns on Embodiment 1 of this invention.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of a target distance detection apparatus according to Embodiment 1 of the present invention, and FIG. 2 shows a specific example of target distance detection in Embodiment 1. In FIG.

The target distance detection device shown in FIG. 1 displays an image of a target of distance measurement obtained by the image sensor 1, and an operation indicator capable of specifying a target type of the target of distance measurement from the display image. 4, a target dimension table 6 storing one or a plurality of types of target dimensions, and a target dimension for retrieving a target dimension from the target dimension table 6 based on the target type designated by the operation display 4. A searcher 5; a target dimension converter 7 for converting the target dimension searched by the target dimension searcher 5 by a swing angle of an image sensor; and a target dimension converted value output by the target dimension converter 7 And a target in the image displayed on the operation display 4 exists from the total number of pixels of the image output from the image sensor and the number of pixels in the vertical or horizontal direction occupied by the target. Eye in position A target plane display range calculator 2 for calculating a plane display range, and a distance calculator for calculating a distance to the target from the target plane display range from the target plane display range calculator 2 and the angle of view from the image sensor. 3 is provided.
Although the image sensor has an angle sensor function and outputs a swing angle, a rotation angle sensor may be provided separately to output the swing angle to the target size converter.

Next, the operation will be described.
In FIG. 1, the operation display 4 displays an image acquired from the image sensor 1, and the operator selects a distance measurement target and inputs an assumed target type from this display image.
The target dimension search unit 5 searches the target dimension table 6 for the target dimension corresponding to the target type input from the operation display unit 4.
The target dimension converter 7 converts the target dimension searched by the target dimension searcher 5 based on the swing angle input from the image sensor 1 to convert the target dimension.
The target surface display range calculator 2 calculates the length of one side of the target surface from the total number of pixels from the image sensor 1 and the number of pixels occupied by the target in the operation display 4.
The distance calculator 3 calculates the distance to the target selected by the operator based on the result of the target plane display range calculator 2.

With reference to FIG. 2, first, in the operation display 4 that displays the image output by the image sensor 1, measurement is performed by, for example, adjusting the target to be measured by the operator to the center of the display screen of the operation display 4. Select the type of distance target.
The target dimension retrieval unit 5 retrieves the distance measurement target dimension from the target dimension table 6 based on the selected target type.
FIG. 3 shows an example of the dimension table 6. For example, when the distance measurement target is a person, a dimension setting value such as a height of 1.8 m and a width of 0.5 m is retrieved.

  Here, a method of converting the target dimension from the swing angle output from the image sensor by the target dimension converter 7 will be described. As shown in FIG. 2, as an example, when the above-mentioned person (height H) and the swing angle are φ, the target dimension converted value is expressed by equation (1).

Next, in the target plane display range calculator 2, the total number of pixels (vertical and horizontal) of the image obtained from the image sensor 1, the number of pixels occupied by the target specified by the operation display 4 (vertical and horizontal), and dimensions The display range of the position where the target for distance measurement exists is calculated from the target dimension converted value 7 converted by the converter 7.

  Here, a calculation method of the target plane display range G at the position where the target of the distance measurement target displayed on the operation display 4 exists will be described. As shown in FIG. 2, as an example, in the vertical direction of the vertical and horizontal directions, the number of vertical pixels of the image sensor 1 is N (vertical), the number of vertical pixels occupied by the target is n, and the actual target searched by the target size searcher If the assumed vertical dimension is L, the target surface display range G is expressed by equation (2).

  Further, the distance calculator 3 calculates the angle of view θ obtained from the image sensor 1 and the distance R from the target plane display range (vertical) G calculated by the target plane display range calculator 2 to the target. Here, the distance R to the target is expressed by Equation (3).

  Finally, the calculated distance R to the target is displayed on the operation display 4. As a result, the operator can grasp the distance from the operator position to the target.

  The above is calculated with respect to the target number of pixels in the vertical direction. For example, when a person to be distance-measured has a spread in the horizontal pixel direction, the expression (1) is also applied to the horizontal pixels. Of course, it becomes possible to measure the distance by applying (2).

  Therefore, according to the first embodiment, it is possible to reduce the target distance error that has conventionally occurred due to the ambiguity of the target dimension that changes depending on the swing angle of the image sensor, and it is possible to accurately measure the distance.

  1 image sensor, 2 target plane display range calculator, 3 distance calculator, 4 operation display, 5 target dimension searcher, 6 target dimension table, 7 target dimension converter.

Claims (2)

An operation indicator capable of displaying a target image of a distance measurement target obtained by the image sensor and capable of specifying a target dimension of the distance measurement target from the display image;
A target dimension table storing target dimensions of one or more types of targets;
A target dimension searcher for searching a target dimension from the target dimension table based on a target type designated by the operation indicator;
A target dimension converter that outputs a target dimension converted value by converting the target dimension searched by the target dimension searcher with the swing angle of the image sensor; and
In the image displayed on the operation display, the target dimension conversion value, the total number of pixels of the image output from the image sensor, and the number of vertical or horizontal pixels occupied by the target are displayed. A target surface display range calculator for calculating a target surface display range at a position where the target exists;
A distance calculator for calculating a distance from the target surface display range and an angle of view from the image sensor to the target;
A target distance detection device comprising: The target dimension converter uses the target dimension conversion value n as the swing angle φ and the target vertical dimension H.

The target distance detection apparatus according to claim 1, wherein the target distance detection apparatus calculates the target distance.

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