An image recognition accelerator applied to a terminal device for image recognition, comprising: a dimensionality-reduction processing module, configured to: receive a dimensionality-reduction parameter γ, and reduce a dimensionality of first image data according to the received dimensionality-reduction parameter γ, wherein the first image data on which dimensionality reduction has been performed comprises multiple numeric values, and the dimensionality-reduction parameter γ is obtained according to a system power consumption of the terminal device and a specified first image recognition success rate of the terminal device; a non-volatile memory, NVM, configured to: receive a width parameter ω and a first current I, store, in a first storage area of the NVM according to the specified first current I, ω low-order bits of each numeric value of the first image data on which dimensionality reduction has been performed, and store, in a second storage area of the NVM according to a specified second current I s, (N-ω) high-order bits of each numeric value of the first image data on which dimensionality reduction has been performed, wherein N is a quantity of bits occupied by each numeric value, the first current I is lower than the second current I s, and the width parameter ω and the first current I are obtained according to the system power consumption of the terminal device and the specified first image recognition success rate of the terminal device; and an image matching module, configured to determine whether an image library stored in the NVM comprises image data matching the first image data on which dimensionality reduction has been performed. a dimensionality-reduction processing module, configured to: receive a dimensionality-reduction parameter γ, and reduce a dimensionality of first image data according to the received dimensionality-reduction parameter γ, wherein the first image data on which dimensionality reduction has been performed comprises multiple numeric values, and the dimensionality-reduction parameter γ is obtained according to a system power consumption of the terminal device and a specified first image recognition success rate of the terminal device; a non-volatile memory, NVM, configured to: receive a width parameter ω and a first current I, store, in a first storage area of the NVM according to the specified first current I, ω low-order bits of each numeric value of the first image data on which dimensionality reduction has been performed, and store, in a second storage area of the NVM according to a specified second current I s, (N-ω) high-order bits of each numeric value of the first image data on which dimensionality reduction has been performed, wherein N is a quantity of bits occupied by each numeric value, the first current I is lower than the second current I s, and the width parameter ω and the first current I are obtained according to the system power consumption of the terminal device and the specified first image recognition success rate of the terminal device; and an image matching module, configured to determine whether an image library stored in the NVM comprises image data matching the first image data on which dimensionality reduction has been performed.