Method and apparatus for generating image data

An apparatus for generating image data, wherein the apparatus comprises:

• a first pixel value obtaining module, configured for obtain a first pixel value of each pixel in a first image based on original pixel values of the first image acquired by an image acquisition device when ambient light brightness is greater than a first preset brightness threshold;
• a second pixel value obtaining module, configured for obtaining a second pixel value of each pixel by dividing the first pixel value of this pixel by a preset multiple;
• wherein the preset multiple is a ratio of original pixel values of a second image acquired by the image acquisition device when the ambient light brightness is greater than the first preset brightness threshold to original pixel values of a third image acquired by the image acquisition device when the ambient light brightness is less than a second preset brightness threshold;
• the second preset brightness threshold is less than the first preset brightness threshold;
• a third pixel value obtaining module, configured for obtaining a third pixel value of each pixel by adding Poisson noise based on a total system gain of the image acquisition device on the basis of the second pixel value of this pixel;
• wherein, the total system gain is determined based on a distribution of original pixel values of a fourth image including a gray-scale plate acquired by the image acquisition device;
• and
• an image data generation module, configured for generating original pixel values of a target image which corresponds to the first image for which the ambient light brightness is less than the second preset brightness threshold based on respective third pixel values.