Image sensing apparatus and method which combine a plurality of images obtained from different areas at different time intervals
An image sensing apparatus has first and second image sensors is provided. In the image sensing apparatus, an optical system forms an optical image on the first and second image sensors; an area-of-interest extracting unit extracts an area of interest from image data output by the second image sensor; an area-of-interest information storage unit stores area-of-interest information indicative of a pixel area in the first image sensor corresponding to the position of the area of interest; a first storage unit stores image data from an entire pixel area of the first image sensor at a time interval; a second storage unit stores image data from the pixel area of the first image sensor indicated by the area-of-interest information, at a shorter time interval; and a combining unit combines the image data stored in the first and second storage units to generate combined image data.
1. An image sensing apparatus having first and second image sensors, comprising:
an optical system configured to form an optical image on the first and second image sensors;
an area-of-interest extracting unit configured to extract an area of interest from image data that is output by the second image sensor;
a first storage unit configured to store image data that is read out from an entire pixel area of the first image sensor at a first time interval;
a second storage unit configured to store image data obtained by reading out only partial area of the first image sensor corresponding to the position of the area of interest at a second time interval shorter than the first time interval; and
a combining unit configured to combine the image data that has been stored in said first storage unit and the image data that has been stored in said second storage unit to thereby generate combined image data.
2. The apparatus according to claim 1 , wherein by the time said first storage unit stores the next image data read out from the entire pixel area of the first image sensor, said combining unit combines the image data that has been stored in said first storage unit and the image data that has been stored in said second storage unit to thereby generate the combined image data.
3. The apparatus according to claim 1 , wherein the first image sensor is a randomly accessible image sensor.
4. An image sensing method of an image sensing apparatus having first and second image sensors and an optical system for forming an optical image on the first and second image sensors, said method comprising:
an area-of-interest extracting step of extracting an area of interest from image data that is output by the second image sensor;
a first storage step of storing image data, which is read out from an entire pixel area of the first image sensor at a first time interval, in a first storage unit;
a second storage step of storing image data in a second storage unit, the image data being obtained by reading out only partial area of the first image sensor corresponding to the position of the area of interest at a second time interval shorter than the first time interval; and
a combining step of combining the image data that has been stored in the first storage unit and the image data that has been stored in the second storage unit to thereby generate combined image data.
5. A computer-readable storage medium storing a program for causing a computer to execute the steps of the image sensing method set forth in claim 4 .