Imaging apparatus and imaging method

Abstract

An imaging apparatus is disclosed which analyzes image data of a subject acquired by an image pickup device to select an appropriate combination of exposure time, aperture, and exposure sensitivity upon shooting in order to perform exposure control. As an example of image data analysis methods, there is shown a method of detecting the movement of a characteristic point in an image, or a method of detecting luminance variations in a specific block or area in the image to detect the subject movement. As another exemplary method, a face of the subject is detected. The present invention can also be combined with a shake reduction mode.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

These and other features, aspects, and advantages of the apparatus and methods of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:

FIG. 1 is a block diagram showing the main blocks of an imaging apparatus with an anti-shake function according to a first embodiment of the present invention;

FIG. 2 is a diagram showing an example of a flow of anti-shake processing based on information captured in an information input part of the imaging apparatus of FIG. 1;

FIG. 3 is a diagram showing exposure control areas selected according to the subject brightness/subject movement when a shake reduction mode is set in the imaging apparatus of FIG. 1;

FIG. 4 shows a standard exposure control program line diagram for wide-angle/telephoto states of the imaging apparatus of FIG. 1 in non-shake reduction modes;

FIG. 5 shows a normal-sensitivity exposure control program line diagram for wide-angle/telephoto states of the imaging apparatus of FIG. 1 in the shake reduction mode;

FIG. 6 shows an intermediate-sensitivity exposure control program line diagram for wide-angle/telephoto states of the imaging apparatus of FIG. 1 in the shake reduction mode;

FIG. 7 shows a high-sensitivity exposure control program line diagram for wide-angle/telephoto states of the imaging apparatus of FIG. 1 in the shake reduction mode;

FIG. 8 is a flowchart of shooting processing in the imaging apparatus of FIG. 1;

FIG. 9 is a diagram showing exposure control areas selected according to the subject brightness/subject movement when the shake reduction mode is set in an imaging apparatus according to a second embodiment of the present invention;

FIG. 10 is a flowchart of shooting processing in the imaging apparatus of FIG. 9;

FIG. 11 is a block diagram showing the main blocks of an imaging apparatus according to a third embodiment of the present invention;

FIG. 12 is a diagram showing an example of a flow of anti-shake processing based on information captured in an information input part of the imaging apparatus of FIG. 11;

FIG. 13 is a diagram showing an example of a mosaic array of RGB pixels of original image data acquired by an image pickup device in the imaging apparatus of FIG. 11;

FIG. 14 is a diagram showing one pixel upon pixel mixing of the original image data in FIG. 13;

FIG. 15 shows a high-sensitivity exposure control program line diagram for wide-angle/telephoto states of the imaging apparatus of FIG. 11 in the shake reduction mode; and

FIG. 16 is a flowchart of shooting processing in the imaging apparatus of FIG. 11.

Claims

1. An imaging apparatus comprising: an image pickup device for capturing a subject image to acquire image data;a movement detection part for detecting a subject movement from the image data acquired by the image pickup device;an exposure sensitivity setting part for setting an exposure sensitivity of the image pickup device;a sensitivity exposure control part for performing exposure control in order to obtain an appropriate exposure amount for the image pickup device, having a plurality of combinations including exposure time, aperture value, and exposure sensitivity upon shooting as exposure control options; andan exposure control switching part for switching the exposure sensitivities and the exposure control options according to the magnitude of the subject movement obtained by the movement detection part.

2. The imaging apparatus according to claim 1 wherein when the subject brightness is lower than a preset brightness, the exposure control switching part switches to exposure control for high exposure sensitivity regardless of the result of the movement detection part.

3. The imaging apparatus according to claim 1 wherein when the subject brightness is higher than a preset brightness, the exposure control switching part switches the exposure sensitivities and the exposure control options according to the magnitude of the subject movement obtained by the movement detection part.

4. The imaging apparatus according to claim 1 further comprising: a shake detection part for detecting the amount of shake upon shooting; anda compensation member cooperates with the sensitivity exposure control part to correct a relative imaging position on the image pickup device during exposure of the subject based on the output of the shake detection part.

5. The imaging apparatus according to claim 1 further comprising an operation part for instructing start of shooting, wherein upon receipt of the shooting start instruction, the sensitivity exposure control part performs exposure control.

6. The imaging apparatus according to claim 1 wherein the movement detection part extracts the subject movement from a luminance variation in each of a plurality of divided blocks in the acquired image.

7. The imaging apparatus according to claim 1 wherein the movement detection part extracts a characteristic point from a moving body in the acquired image to detect the subject movement based on the movement of the characteristic point.

8. An imaging method comprising: acquiring image data of a subject through an image pickup device;detecting a subject movement from the image data acquired through the image pickup device;switching, according to the magnitude of the subject movement, the exposure sensitivities of the image pickup device and a plurality of exposure control options, the plurality of exposure control options being the combinations including exposure time, aperture value, and exposure sensitivity upon shooting for obtaining an appropriate exposure amount for the image pickup device; andperforming imaging.

9. An imaging apparatus with anti-shake capability, comprising: a shake detection part;an information input part into which information including information from the shake detection part is input;a compensation member for adjusting a relative imaging position of a subject on an image pickup device upon shooting;a shake compensation part for controlling the driving of the compensation member upon shooting based on the output of the shake detection part to compensate for a shift in position due to the shake of the imaging apparatus; anda high sensitivity exposure control part for controlling the image pickup device to change the sensitivity of the image pickup device to a high sensitivity,wherein at least either of the shake compensation part and the high sensitivity exposure control part is actuated according to the output of the information input part.

10. The imaging apparatus with anti-shake capability according to claim 9, wherein the information input into the information input part includes subject brightness information.

11. The imaging apparatus with anti-shake capability according to claim 9, wherein the information input into the information input part includes subject movement information.

12. The imaging apparatus with anti-shake capability according to claim 9, wherein the subject movement information is extracted based on a luminance variation in each of a plurality of divided blocks in an acquired image.

13. The imaging apparatus with anti-shake capability according to claim 9, wherein the subject movement information is extracted based on variations in characteristic points extracted from a moving body in an acquired image.

14. An imaging apparatus comprising: a shake detection part;an information input part into which information including information from the shake detection part is input;a compensation member for adjusting a relative imaging position of a subject on an image pickup device upon shooting;a shake compensation part for controlling the driving of the compensation member upon shooting based on the output of the shake detection part to compensate for a shift in position due to the shake of the imaging apparatus; anda pixel mixing control part for mixing predetermined pixels on the image pickup device to output the mixing results,wherein at least either of the shake compensation part and the pixel mixing control part is actuated upon shooting with the imaging apparatus according to the output of the information input part.

15. The imaging apparatus according to claim 14 wherein the information input into the information input part includes shooting mode information, and when any one of a aperture priority mode, a shutter speed priority mode, a landscape mode, a macro mode, and a portrait mode is set as the shooting mode in the shooting mode information, only the shake compensation part is actuated.

16. The imaging apparatus according to claim 14 wherein the information input into the information input part includes subject brightness information, and when the subject brightness information is lower than a predetermined brightness, both the shake compensation part and the pixel mixing control part are actuated.

17. An imaging apparatus comprising: an image pickup device for capturing a subject image to acquire image data;a face detection part for detecting face information in the subject from the image data acquired by the image pickup device;an exposure sensitivity setting part for setting an exposure sensitivity of the image pickup device;a sensitivity exposure control part for performing exposure control in order to obtain an appropriate exposure amount for the image pickup device, having a plurality of combinations including exposure time, aperture, and exposure sensitivity upon shooting as exposure control options; andan exposure control switching part for switching the exposure sensitivities and the exposure control options according to the face information of the subject obtained by the face detection part.

18. The imaging apparatus according to claim 17 wherein the exposure sensitivity setting part at least performs a setting of the exposure sensitivity through a pixel mixing and reading in which a plurality of signals from the image pickup device are mixed and read.

19. The imaging apparatus according to claim 18 further comprising an operation part for setting a shooting mode, wherein when a shooting mode requiring the designation of either an aperture value or a shutter speed is set, the exposure control switching part performs exposure sensitivity setting to prohibit the pixel mixing and reading regardless of the face information.

20. The imaging apparatus according to claim 18 wherein the pixel mixing and reading is to mix N×N pixel signals in the pixels on the image pickup device, where N is a natural number larger than 1.

21. The imaging apparatus according to claim 18 further comprising an operation part for setting a shooting scene, wherein when any one of landscape shooting, macro shooting, and portrait shooting is selected as the shooting scene, the exposure control switching part performs exposure sensitivity setting to prohibit the pixel mixing and reading regardless of the face information.

22. The imaging apparatus according to claim 17 wherein when a face having a size that meets a preset condition as the face information exists in the acquired image, exposure sensitivity setting is performed to prohibit the pixel mixing and reading.

23. The imaging apparatus according to claim 17 further comprising a shake compensation part, wherein when the shake compensation part is to be operated, exposure sensitivity setting is performed to prohibit the pixel mixing and reading.

24. An imaging method comprising: capturing a subject image by an image pickup device to acquire image data;detecting face information in the subject from the image data acquired by the image pickup device;switching exposure sensitivities of the image pickup device according the face information of the detected subject; andshooting under an exposure option selected from a plurality of exposure control options for performing exposure control in order to obtain an appropriate exposure amount for the image pickup device, the plurality of exposure control options being combinations of exposure time, aperture value, and exposure sensitivity upon shooting.