IMAGE CODING METHOD, IMAGE DECODING METHOD, IMAGE CODING APPARATUS, IMAGE DECODING APPARATUS, IMAGE CODING AND DECODING APPARATUS

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.