Focus adjusting apparatus, focus adjusting method, and image capturing apparatus
AssigneeCanon Kabushiki Kaisha
InventorRyosuke Tsuji
Life of this patent
Estimating the term…
Abstract
In a focus adjusting apparatus, a tracking unit detects from an image signal an area of a subject to be tracked, a position of an imaging plane of the area and reliability of the position, and a prediction unit predicts a position of an imaging plane when the image signal was obtained based on a history of detected positions of imaging planes. A setting unit sets a tolerance based on the reliability, and a determination unit determines the area of the detected subject as a focus adjustment area if a difference between the predicted and detected positions is within the tolerance. The prediction unit predicts a position of an imaging plane of the subject in the focus adjustment area at a future time point.
Claims17
A focus adjusting apparatus, comprising at least one processor or one circuitry which functions as:
- a tracking unit that detects an area of a subject to be tracked, a position of an imaging plane of the area, and reliability of the position of the imaging plane from an image signal that has been output from an image sensor through photoelectric conversion of light incident on the image sensor;
- a prediction unit that predicts a position of an imaging plane at a preset time point based on a history of positions of imaging planes detected by the tracking unit;
- a setting unit that sets a tolerance for positions of imaging planes based on the reliability detected by the tracking unit;
- and
- a determination unit that determines the area of the subject detected by the tracking unit as a focus adjustment area in a case where a difference between a position that has been predicted by the prediction unit as a position of an imaging plane at a time point of shooting associated with the image signal and the position of the imaging plane detected by the tracking unit is within the tolerance.
An image capturing apparatus, comprising at least one processor or one circuitry which functions as:
- an image sensor that outputs an image signal through photoelectric conversion of light incident thereon;
- and
- the focus adjusting apparatus that includes:
- a tracking unit that detects an area of a subject to be tracked, a position of an imaging plane of the area, and reliability of the position of the imaging plane from the image signal that has been output from the image sensor;
- a prediction unit that predicts a position of an imaging plane at a preset time point based on a history of positions of imaging planes detected by the tracking unit;
- a setting unit that sets a tolerance for positions of imaging planes based on the reliability detected by the tracking unit;
- and
- a determination unit that determines the area of the subject detected by the tracking unit as a focus adjustment area in a case where a difference between a position that has been predicted by the prediction unit as a position of an imaging plane at a time point of shooting associated with the image signal and the position of the imaging plane detected by the tracking unit is within the tolerance.
A focus adjusting method, comprising:
- detecting an area of a subject to be tracked, a position of an imaging plane of the area, and reliability of the position of the imaging plane from an image signal that has been output from an image sensor through photoelectric conversion of light incident on the image sensor;
- predicting a position of an imaging plane at a time point of shooting associated with the image signal based on a history of detected positions of imaging planes;
- setting a tolerance for positions of imaging planes based on the detected reliability;
- and
- determining the detected area of the subject as a focus adjustment area in a case where a difference between the predicted position of the imaging plane at the time point of shooting associated with the image signal and the detected position of the imaging plane is within the tolerance.
A computer-readable storage medium having stored therein a program for causing a computer to function as the units of the focus adjusting apparatus that comprises:
- a tracking unit that detects an area of a subject to be tracked, a position of an imaging plane of the area, and reliability of the position of the imaging plane from an image signal that has been output from an image sensor through photoelectric conversion of light incident on the image sensor;
- a prediction unit that predicts a position of an imaging plane at a preset time point based on a history of positions of imaging planes detected by the tracking unit;
- a setting unit that sets a tolerance for positions of imaging planes based on the reliability detected by the tracking unit;
- and
- a determination unit that determines the area of the subject detected by the tracking unit as a focus adjustment area in a case where a difference between a position that has been predicted by the prediction unit as a position of an imaging plane at a time point of shooting associated with the image signal and the position of the imaging plane detected by the tracking unit is within the tolerance.
Dependencies are inferred from the claim text.