White balance compensation method and electronic apparatus using the same

An electronic apparatus, comprising:

• an image capturing unit;
• a storage unit, storing a plurality of modules;
• and
• a processing unit, coupled to the image capturing unit and the storage unit, and accessing the modules to execute following steps:
• obtaining a first specific color ratio and a second specific color ratio of a predetermined color in a predetermined color temperature;
• obtaining a first reference color ratio and a second reference color ratio of a reference color in the predetermined color temperature;
• controlling the image capturing unit to capture an image comprising a plurality of pixels, and obtain an exposure index corresponding to the image, wherein each pixel has a first color ratio and a second color ratio;
• retrieving a plurality of specific pixels from the pixels when the exposure index corresponds to the predetermined color temperature;
• calculating a plurality of white balance compensation values of the image according to the specific pixels;
• obtaining an image color temperature of the image;
• updating the white balance compensation values according to the first reference color ratio and the second reference color ratio when the image color temperature corresponds to the predetermined color temperature;
• and
• performing a white balance operation to each of the pixels according to the updated white balance compensation values to generate a compensated image.