초록 ▼

In a camera having a gamma-correction circuit on an output signal processing path of a CCD, an incident light path leading to the CCD is kept opening in a state where nonlinear gamma-correction processing in the gamma-correction processing circuit is prohibited, first image data (CCD output data; DA

In a camera having a gamma-correction circuit on an output signal processing path of a CCD, an incident light path leading to the CCD is kept opening in a state where nonlinear gamma-correction processing in the gamma-correction processing circuit is prohibited, first image data (CCD output data; DATA1) are generated based on electric signal output from the CCD, incident light path leading to the CCD is kept closing, second image data (CCD output data; DATA2) are generated based on electric signal output from the CCD and lastly, the second image data DATA2are subtracted from the first image data DATA1, thereby correcting to eliminate dark voltage component included in the first image data DATA1.

대표청구항 ▼

1. A camera comprising: image pick-up means for outputting image data in accordance with incident light; first pick-up control means for obtaining first image data output from the image pick-up means under a condition where an incident light path of the image pick-up means is opened; second

1. A camera comprising: image pick-up means for outputting image data in accordance with incident light; first pick-up control means for obtaining first image data output from the image pick-up means under a condition where an incident light path of the image pick-up means is opened; second pick-up control means for obtaining second image data output from the image pick-up means under a condition where the incident light path of the image pick-up means is closed; means for correcting the first image data obtained by the first pick-up control means based on the second image data obtained by the second pick-up control means; first nonlinear processing means for subjecting the image data output from the image pick-up means to nonlinear processing; and means for prohibiting the nonlinear processing for the image data by said first nonlinear processing means when the first and second image data are obtained by the first and second pick-up control means, wherein said first pick-up control means and said second pick-up control means obtain the fist image data and the second image data which are not subjected to the nonlinear processing by said first nonlinear processing means. 2. The camera according to claim 1, wherein said prohibiting means prohibits the nonlinear processing by subjecting the image data output from the image pick-up means to linear processing.3. The camera according to claim 2, wherein said first nonlinear processing means comprises a first gamma-correction table having nonlinear characteristic and a second gamma-correction table having linear characteristic, carries out the nonlinear processing using the first gamma-correction table, and carries out the linear processing using the second gamma-correction table instead of the first gamma-correction table if the nonlinear processing is prohibited by said prohibiting means.4. The camera according to claim 1, wherein said first nonlinear processing means carries out the nonlinear processing using a gamma-correction circuit, and said prohibiting means prohibits the nonlinear processing by allowing the image data output from said image pick-up means to bypass said gamma-correction circuit. 5. The camera according to claim 1, wherein said correcting means corrects the first image data by subtracting the second image data from the first image data.6. The camera according to claim 1, further comprising second nonlinear processing means for subjecting the first image data corrected by said correcting means to nonlinear processing.7. The camera according to claim 6, wherein said first nonlinear processing means carries out the nonlinear processing using a gamma-correction circuit, and said second nonlinear processing means carries out the nonlinear processing for the first image data using said gamma-correction circuit. 8. The camera according to claim 1, further comprising means for storing the first image data which is corrected by said correcting means.9. The camera according to claim 1, wherein said first pick-up control means is activated in response to a depression of a shutter key switch and said second pick-up control means is activated in response to a completion of first image data-obtaining by said first pick-up control means.10. The camera according to claim 1, further comprising optical path opening/closing means, and wherein said first pick-up control means opens the incident light path leading to said image pick-up means using said optical path opening/closing means, and said second pick-up control means closes the incident light path leading to said image pick-up means using said optical path opening/closing means. 11. The camera according to claim 1, further comprising means for setting a special effect mode as an image pick-up mode, and wherein said first and second pick-up control means obtain the first and second image data when the special effect mode is set by said special effect mode setting means.12. The camera accordi ng to claim 1, further comprising third pick-up control means for obtaining third image data which is output from said image pick-up means in a state where the incident optical path leading to said image pick-up means is opened and which is subjected to the nonlinear processing by said first nonlinear processing means.13. The camera according to claim 12, further comprising means for displaying the third image data obtained by said third pick-up control means.14. The camera according to claim 13, wherein the third image data obtained by said third pick-up control means is displayed on said displaying means as a finder image.15. The camera according to claim 12, further comprising means for setting a normal pick-up mode as an image pick-up mode, and wherein said third pick-up control means obtains the third image data when the normal pick-up mode is set by said normal pick-up mode setting means.16. A camera comprising: image pick-up means for outputting image data in accordance with incident light; first pick-up control means for obtaining first image data output from the image pick-up means under a condition where an incident light path of the image pick-up means is opened; second pick-up control means for obtaining second image data output from the image pick-up means under a condition where the incident light path of the image pick-up means is closed; means for determining whether a level of the first image data obtained by the first pick-up control means is saturated; and means for correcting the first image data obtained by the first pick-up control means based on a result of determination made by the determining means and based on the second image data obtained by the second pick-up control means. 17. A camera comprising: an image sensor which outputs image data in accordance with incident light; first pick-up control means for obtaining first image data output from the image sensor under a condition where an incident light path of the image sensor is opened; second pick-up control means for obtaining second image data output from the image sensor under a condition where the incident light path of the image sensor is closed; means for correcting the first image data obtained by the first pick-up control means based on the second image data obtained by the second pick-up control means; a gamma-correction circuit which non-linearly corrects a gamma characteristic of the image data output from the image sensor; and means for prohibiting the gamma characteristic correction for the image data by said gamma-correction circuit when the first and second image data are obtained by the first and second pick-up control means, wherein said first pick-up control means and said second pick-up control means obtain the fist image data and the second image data which are not subjected to the gamma characteristic correction. 18. A signal processing method for a camera which carries out nonlinear processing for image data output from an image sensor, comprising steps of: prohibiting the nonlinear processing for the image data output from the image sensor under a condition where an incident light path of the image sensor is opened, thereby obtaining first image data which are not subjected to the nonlinear processing; step of prohibiting the nonlinear processing for the image data output from the image sensor under a condition where the incident light path of the image sensor is closed, thereby obtaining second image data which are not subjected to the nonlinear processing; and correcting the first image data based on the second image data. 19. A signal processing method for a camera, comprising steps of: obtaining first image data output from an image sensor under a condition where an incident light path of the image sensor is opened; obtaining second image data output from an image sensor under a condition where an incident light path of the image sensor is closed; determining whether a lev el of the first image data is saturated; and correcting the first image data based on a result of the determination and the second image data.