Imaging apparatus and signal processing method for checking a photographed image in a multi-band camera immediately
Output signals (pixel values) output from a sensor unit in which image sensors having six kinds of color filters with different colors are arranged are classified in association with three stimulus values, a color number is reduced by performing addition processing of the output signals (pixel values) in each classification to generate an image signal of three bands, and the generated image signal is used for the preview display so that a photographed image can be checked easily and immediately.
1. An imaging apparatus, comprising:
an imaging unit in which image sensors having four kinds of color filters or more with different colors are arranged;
a color number reduction processing unit which generates an image signal of three bands corresponding to three stimulus values, from output signals corresponding to the four kinds of color filters or more output from the imaging unit; and
an auto-focus control unit which controls focusing of an object image in the imaging unit based on the image signal generated by the color number reduction processing unit.
2. The imaging apparatus according to claim 1 , further comprising a white balance processing unit which performs white balance processing based on the image signal of the three bands generated by the color number reduction processing unit.
3. The imaging apparatus according to claim 1 , wherein the color number reduction processing unit classifies the four kinds of color filters or more into three kinds corresponding to three different basic wavelengths that are preset according to differences between the basic wavelengths and main wavelengths of the color filters and generates the image signal of the three bands by adding the output signals corresponding to the color filters in each classification.
4. The image apparatus according to claim 1 , wherein the color number reduction processing unit selects the output signals corresponding to three kinds of the color filters that minimize differences between three different basic wavelengths that are preset and main wavelengths of the color filters, from the output signals corresponding to the four kinds of color filters or more to generate the image signal of the three bands.
5. The imaging apparatus according to claim 1 , further comprising a high-precision image generation unit which generates the image signal more precise than the image signal of the three bands generated by the color number reduction processing unit, from the output signals corresponding to the four kinds of color filters or more,
wherein at least one of the image signal of the three bands generated by the color number reduction processing unit and the high-precision image signal generated by the high-precision image generation unit is recorded.
6. The imaging apparatus according to claim 5 , further comprising a selection unit which selects the image signal to be recorded.
7. An image processing method, comprising:
generating an image signal of three bands corresponding to three stimulus values, from output signals corresponding to four kinds of color filters or more output from an imaging unit in which image sensors having the four kinds of color filters or more with different colors are arranged; and
controlling focusing of an object image in the imaging unit based on the generated image signal.
8. The image processing method according to claim 7 , further comprising:
performing white balance processing based on the image signal of the three bands.
9. The imaging processing method according to claim 7 , further comprising:
classifying the four kinds of color filters or more into three kinds corresponding to three different basic wavelengths that are preset according to differences between the basic wavelengths and main wavelengths of the color filters, and
generating the image signal of the three bands by adding the output signals corresponding to the color filters in each classification.
10. The image processing method according to claim 7 , further comprising selecting the output signals corresponding to three kinds of the color filters that minimize differences between three different basic wavelengths that are preset and main wavelengths of the color filters, from the output signals corresponding to the four kinds of color filters or more to generate the image signal of the three bands.
11. The imaging processing method according to claim 7 , further comprising generating the image signal more precise than the image signal of the three bands, from the output signals corresponding to the four kinds of color filters or more,
wherein at least one of the image signal of the three bands and the high-precision image signal is recorded.
12. The image processing method according to claim 11 , further comprising selecting the image signal to be recorded.
13. A non-transitory storage computer-readable medium characterized by storing a control program to cause a computer to implement an imaging apparatus of claim 1 .