Disclosed is a method for converting image data. The method includes: acquiring image data of a target image, wherein the image data includes first pixel values of m pixels in the target image, each of the first pixel values includes a first color value of at least one color channel, the first color value being within a target color value interval of the at least one color channel; dividing the target color value interval into n color value partitions; determining a color value partition where the first color value falls from the n color value partitions; and converting the first color value into a second color value according to a position of the first color value in the color value partition, the number of bits occupied by the second color value being less than the number of bits occupied by the first color value.