초록 ▼

An image pickup apparatus and method which reduces fixed pattern noise appearing in multiple exposure shooting and which can obtain a high-quality multiple exposure image. Multiple pieces of exposure image data are obtained by exposing an image pickup device. The multiple pieces of exposure image da

An image pickup apparatus and method which reduces fixed pattern noise appearing in multiple exposure shooting and which can obtain a high-quality multiple exposure image. Multiple pieces of exposure image data are obtained by exposing an image pickup device. The multiple pieces of exposure image data are subjected to image processing. The multiple pieces of image processed exposure image data are synthesized to generate synthesized exposure image data. Multiple pieces of dark image data are obtained by shielding the image pickup device from light. Each of the multiple pieces of dark image data is subjected to image processing equivalent to image processing performed on a corresponding one of the multiple pieces of exposure image data. The multiple pieces of image processed dark image data that are synthesized to generate synthesized dark image data. The synthesized exposure image data is corrected on the basis of the synthesized dark image data.

대표청구항 ▼

1. An image pickup apparatus comprising: an image pickup for picking up a subject image and outputting image data;an image processor for subjecting the image data that is output from the image pickup to image processing, wherein the image processing includes at least one of an optical shading correc

1. An image pickup apparatus comprising: an image pickup for picking up a subject image and outputting image data;an image processor for subjecting the image data that is output from the image pickup to image processing, wherein the image processing includes at least one of an optical shading correction process or a white balance correction process;a synthesizer for synthesizing a plurality of pieces of image data; anda corrector,wherein the image pickup apparatus further includes a controller which performs control in such a manner that the image pickup obtains a plurality of pieces of exposure image data by exposing an image pickup device thereof to light to pick up images,the image processor subjects the plurality of pieces of exposure image data to the image processing,the synthesizer synthesizes the plurality of pieces of exposure image data that are output from the image processor, to generate synthesized exposure image data,the image pickup obtains dark image data by shielding the image pickup device from light to pick up an image,the image processor subjects the dark image data to the image processing using a parameter based on a parameter used in the image processing performed on a corresponding one of the plurality of pieces of exposure image data, and outputs a plurality of pieces of processed dark image data,the synthesizer synthesizes the plurality of pieces of processed dark image data that are output from the image processor, to generate synthesized dark image data, andthe corrector corrects the synthesized exposure image data on the basis of the synthesized dark image data. 2. The image pickup apparatus according to claim 1, wherein the synthesizer synthesizes a plurality of pieces of image data through addition. 3. The image pickup apparatus according to claim 1, wherein the corrector subtracts the synthesized dark image data from the synthesized exposure image data. 4. The image pickup apparatus according to claim 1, wherein the corrector includes a projection calculator for averaging pieces of image data in the vertical direction or in the horizontal direction to obtain projection data, andwherein the projection calculator converts the synthesized dark image data into one-dimensional data, the one-dimensional data is copied a plurality of times, as many as the number of vertical lines or horizontal lines of one screen, so as to be transformed into image data corresponding to one screen, and the image data corresponding to one screen is subtracted from the synthesized exposure image data. 5. The image pickup apparatus according to claim 1, wherein the image processor determines a parameter by using an image pickup condition including at least one of the type of an image pickup lens, a lens zoom position, an aperture, a shutter speed, a setting of ISO sensitivity, and a temperature, and performs image processing by using the parameter. 6. The image pickup apparatus according to claim 1, wherein the controller is capable of performing a first correction process and a second correction process, the first correction process being a process in which control is performed in such a manner that the image pickup obtains a plurality of pieces of dark image data by shielding the image pickup device from light to pick up images,the image processor subjects each of the plurality of pieces of dark image data to image processing equivalent to image processing performed on a corresponding one of the plurality of pieces of exposure image data,the synthesizer synthesizes the plurality of pieces of dark image data which are output from the image processor, to generate synthesized dark image data, andthe corrector corrects the synthesized exposure image data on the basis of the synthesized dark image data,the second correction process being a process in which control is performed in such a manner that the image pickup obtains a plurality of pieces of dark image data by shielding the image pickup device from light to pick up images,the synthesizer generates one piece of dark reference image data by using the plurality of pieces of dark image data,the image processor subjects the one piece of dark reference image data to image processing using a parameter based on a parameter used in image processing performed on a corresponding one of the plurality of pieces of exposure image data and outputs a plurality of pieces of processed dark image data which correspond to the plurality of pieces of exposure image data,the synthesizer synthesizes the plurality of pieces of processed dark image data which are output from the image processor, to generate synthesized dark image data, andthe corrector corrects the synthesized exposure image data on the basis of the synthesized dark image data, andwherein the controller selectively performs either one of the first correction process and the second correction process in accordance with an image pickup condition which has been set. 7. The image pickup apparatus according to claim 6, wherein the image pickup condition which has been set includes at least one of the number of pieces of the exposure image data to be picked up, an ISO sensitivity, and the temperature of the image pickup device. 8. A method for controlling an image pickup apparatus, the method comprising: a first image pickup step of obtaining a plurality of pieces of exposure image data by exposing an image pickup device thereof to light to pick up images;a first image processing step in which the plurality of pieces of exposure image data are subject to image processing, and a plurality of pieces of processed exposure image data are output;a first synthesizing step of generating synthesized exposure image data from the plurality of pieces of processed exposure image data that are output from the first image processing step;a second image pickup step of obtaining dark image data by shielding the image pickup device from light to pick up an image;a second image processing step in which the dark image data is subject to image processing using a parameter based on a parameter used in the first image processing step performed on a corresponding one of the plurality of pieces of exposure image data, and a plurality of pieces of processed dark image data are output;a second synthesizing step of generating synthesized dark image data from the plurality of pieces of processed dark image data that are output from the second image processing step; anda correction step of correcting the synthesized exposure image data on the basis of the synthesized dark image data,wherein the image processing in the first image processing step and the second image processing step, includes at least one of an optical shading correction process or a white balance correction process. 9. A non-transitory computer readable storage medium that stores a program that causes a computer to execute the steps in the method, according to claim 8, for controlling an image pickup apparatus. 10. An image pickup apparatus comprising: an image pickup for picking up a subject image and outputting image data;an image processor for subjecting the image data that is output from the image pickup to image processing, wherein the image processing includes at least one of an optical shading correction process or a white balance correction process;a synthesizer for synthesizing a plurality of pieces of image data; anda corrector,wherein the image pickup apparatus further includes a controller which performs control in such a manner that the image pickup obtains a plurality of pieces of exposure image data by exposing an image pickup device thereof to light to pick up images,the image processor subjects the plurality of pieces of exposure image data to the image processing,the synthesizer synthesizes the plurality of pieces of exposure image data that are output from the image processor, to generate synthesized exposure image data,the image pickup obtains dark image data by shielding the image pickup device from light to pick up an image with a period for accumulation in dark image data pickup operation is shorter than a period for accumulation in exposure image data pickup operation,the image processor subjects the dark image data to the image processing using a parameter based on a parameter used in the image processing performed on a corresponding one of the plurality of pieces of exposure image data, and outputs a plurality of pieces of processed dark image data,the synthesizer synthesizes the plurality of pieces of processed dark image data that are output from the image processor, to generate synthesized dark image data, andthe corrector corrects the synthesized exposure image data on the basis of the synthesized dark image data. 11. The image pickup apparatus according to claim 10, wherein the corrector includes a projection calculator for averaging pieces of image data in the vertical direction or in the horizontal direction to obtain projection data, and wherein the projection calculator converts the synthesized dark image data into one-dimensional data, the one-dimensional data is copied a plurality of times, as many as the number of vertical lines or horizontal lines of one screen, so as to be transformed into image data corresponding to one screen, and the image data corresponding to one screen is subtracted from the synthesized exposure image data.