Image capturing apparatus

Abstract

An image capturing apparatus can use a reading time from an image sensor efficiently. To achieve the object, the image capturing apparatus includes an image capturing unit which separates a color image of a subject being captured by an image sensor having pixels of colors into three or more fields and outputs said three or more fields successively, and an image processing unit which generates a low-resolution image which is lower in resolution than the color image obtained by the image capturing unit, based on output of one or more fields among said three or more fields, said one or more fields being able to extract color information of all the colors, wherein the image processing unit starts generation of the low-resolution image in a period in which fields other than said one or more fields for generating the low-resolution image are read.

1 . An image capturing apparatus comprising:
 an image capturing unit which separates a color image of a subject being captured by an image sensor having pixels of colors into three or more fields and outputs said three or more fields successively; and   an image processing unit which generates a low-resolution image which is lower in resolution than the color image obtained by the image capturing unit, based on output of one or more fields among said three or more fields, said one or more fields being able to extract color information of all the colors, wherein   the image processing unit starts generation of the low-resolution image in a period in which fields other than said one or more fields for generating the low-resolution image are read.   
   
   
       2 . The image capturing apparatus according to  claim 1 , wherein:
 the low-resolution image is an image for checking a result of capturing; and   the image capturing apparatus further comprises a display unit which displays the low-resolution image when the low-resolution image is generated by the image processing unit.   
   
   
       3 . The image capturing apparatus according to  claim 1 , further comprising a field selecting unit which selects one field from the fields, wherein:
 the image processing unit includes a pre-processing part which performs pre-processing on the color image output from the image capturing unit and a post-processing part which directly receives an output of the pre-processing part and performs post-processing on the pre-processed color image; and   when the low-resolution image is to be generated, the color image of one field selected by the field selecting unit is directly transferred from the pre-processing part to the post-processing part to thereby perform the pre-processing and the post-processing integrally and sequentially.   
   
   
       4 . The image capturing apparatus according to  claim 3 , wherein:
 the image processing unit generates a first image lower in resolution and a second image lower in resolution; and   the field selecting unit selects one field for generating the first image and one field for generating the second image, respectively.   
   
   
       5 . The image capturing apparatus according to  claim 1 , wherein:
 the image processing unit includes a pre-processing part which performs pre-processing on the color image output from the image capturing unit, a post-processing part which performs post-processing on the pre-processed color image, and a pixel averaging part which directly receives an output of the post-processing part and averages any pixels of the post-processed color image; and   when the low-resolution image is to be generated, a first low-resolution image is generated by the post-processing part and the generated first low-resolution image is directly transferred from the post-processing part to the pixel averaging part to thereby generate a second low-resolution image which is lower in resolution than the first low-resolution image simultaneously.   
   
   
       6 . The image capturing apparatus according to  claim 1 , wherein:
 the image processing unit includes a white balance adjusting part; and   when the low-resolution image is to be generated, the white balance adjusting part performs white balance adjustment in accordance with a white balance adjustment value decided in advance.   
   
   
       7 . The image capturing apparatus according to  claim 1 , wherein:
 the image processing unit includes a pre-processing part which performs pre-processing on the color image output from the image capturing unit and a post-processing part which performs post-processing on the pre-processed color image;   the image capturing apparatus further comprises a plurality of buffer memory areas which store the color image pre-processed by the pre-processing part and a high-speed continuous capturing mode which performs, as parallel processing, a process of performing the pre-processing on the color image of one frame output from the image capturing unit and storing the pre-processed color image in one of the buffer memory areas and a process of performing the post-processing on the color image of a previous frame stored in another of the buffer memory areas; and   the image processing unit does not start generation of the low-resolution image in a period of reading of fields other than said one or more fields for generating the low-resolution image while image capturing is executed in the high-speed continuous capturing mode.