1. A control method, applied for controlling an electronic device, wherein the electronic device comprises an imaging apparatus and a displayer, the imaging apparatus comprises an image sensor, the image sensor comprises an array of photosensitive pixel units and an array of filter units arranged on the array of photosensitive pixel units, each filter unit corresponds to one photosensitive pixel unit, and each photosensitive pixel unit comprises a plurality of photosensitive pixels, the control method comprises: controlling the image sensor to output a merged image, wherein, the merged image comprises an array of merged pixels, and a plurality of photosensitive pixels in each photosensitive pixel unit are collectively output as one merged pixel; dividing the merged image into a plurality of analysis regions arranged in an array; computing a phase difference of each of the plurality of analysis regions; merging analysis regions each with a phase difference conforming to a preset condition into a focusing area; identifying whether there is a face in the focusing area; when there is the face in the focusing area, converting the merged image into a merged true-color image; when there is no face in the focusing area, determining whether a brightness of the focusing area is less than or equal to a brightness threshold, whether a green proportion of the focusing area is less than or equal to a proportion threshold and whether a space frequency of the focusing area is less than or equal to a frequency threshold; when the brightness of the focusing area is less than or equal to the brightness threshold, the green proportion is less than or equal to the proportion threshold and the space frequency is less than or equal to the frequency threshold, converting the merged image into the merged true-color image; when the brightness of the focusing area is greater than the brightness threshold, the green proportion is greater than the proportion threshold and the space frequency is greater than the frequency threshold, controlling the image sensor to output a color-block image, wherein, the color-block image comprises image pixel units arranged in a preset array, each image pixel unit comprises a plurality of original pixels, and each photosensitive pixel corresponds to one original pixel; converting the color-block image into a simulation image, wherein, the simulation image comprises simulation pixels arranged in an array, the simulation pixels comprise current pixels, the original pixels comprise association pixels corresponding to positions of the current pixels; wherein converting the color-block image into the simulation image comprises: determining whether a color of a first current pixel is identical to a first association pixel; when the color of the first current pixel is identical to the first association pixel, determining a pixel value of the first association pixel as a pixel value of the first current pixel; and when the color of the first current pixel is different from the association pixel, calculating the pixel value of the first current pixel according to a pixel value of an association pixel unit by a first interpolation algorithm, wherein an image pixel unit comprises the association pixel unit, the association pixel unit has the same color with the first current pixel and is adjacent to the first association pixel; and converting the simulation image into a simulation true-color image.