A signal correction method, wherein the method comprises: receiving an input signal, wherein the input signal is an audio signal or an image signal, the input signal comprises signals that are corresponding to multiple units respectively, and each unit is a sampling point of the audio signal or a pixel unit of the image signal; performing texture detection on a target unit in the input signal according to a signal of at least one unit to obtain a first signal, wherein the target unit is one of the multiple units, wherein the target unit and the at least one unit are within a neighborhood, and wherein the first signal reflects flatness of an area in which the target unit is located or flatness of a nearby area, as determined from the absolute difference between signals of neighboring units; by using a high-pass filter, a band-pass filter, or a wavelet transform algorithm, extracting a high frequency component of a signal of the target unit according to the signal of the at least one unit within the neighborhood to obtain a second signal; performing power processing, multiplication processing and non-linear processing on the first signal and the second signal to obtain a sharpness correction signal, wherein for performing the multiplication the first signal is raised to the power of b and the second signal is raised to the power of a, and for performing the non-linear processing the result of the multiplication process is raised to the power of 1/(a+b), and wherein a and b are rational numbers not less than 0, so that an amplitude of the sharpness correction signal has a linear relationship with an amplitude of the signal of the target unit; and performing sharpness correction on the signal of the target unit by calculating a sum of the signal of the target unit and the sharpness correction signal. receiving an input signal, wherein the input signal is an audio signal or an image signal, the input signal comprises signals that are corresponding to multiple units respectively, and each unit is a sampling point of the audio signal or a pixel unit of the image signal; performing texture detection on a target unit in the input signal according to a signal of at least one unit to obtain a first signal, wherein the target unit is one of the multiple units, wherein the target unit and the at least one unit are within a neighborhood, and wherein the first signal reflects flatness of an area in which the target unit is located or flatness of a nearby area, as determined from the absolute difference between signals of neighboring units; by using a high-pass filter, a band-pass filter, or a wavelet transform algorithm, extracting a high frequency component of a signal of the target unit according to the signal of the at least one unit within the neighborhood to obtain a second signal; performing power processing, multiplication processing and non-linear processing on the first signal and the second signal to obtain a sharpness correction signal, wherein for performing the multiplication the first signal is raised to the power of b and the second signal is raised to the power of a, and for performing the non-linear processing the result of the multiplication process is raised to the power of 1/(a+b), and wherein a and b are rational numbers not less than 0, so that an amplitude of the sharpness correction signal has a linear relationship with an amplitude of the signal of the target unit; and performing sharpness correction on the signal of the target unit by calculating a sum of the signal of the target unit and the sharpness correction signal.