Image encoding method, image decoding method, image encoding device, image decoding device, and image encoding/decoding device

摘要

An image encoding method capable of improving encoding efficiency, an image encoding device, an image decoding method, an image decoding device, and an image encoding/decoding device are provided. The image encoding method includes: an encoding target signal acquisition step (S401) that obtains a target signal for encoding which is contained in an image data processing unit; a binarisation step (S402) that generates a binary signal by binarising the target signal; a context selection step (S403) that selects a context for the target signal from a plurality of contexts; an arithmetic encoding step (S404) that arithmetically encodes the binary signal using encoding probability information associated with the context selected in the context selection step; and an update step (S405) that updates the encoding probability information on the basis of the binary signal. The context selection step selects a common context for the target signal and a target signal with a different processing unit size.