Image coding method, image decoding method, image coding apparatus, and image decoding apparatus

摘要

An image coding method for performing compression-coding on image data includes: binarizing a signal to be coded of the image data, to generate a binary signal; determining a low-order context which is a context associated with a type of the signal to be coded, and a high-order context that is common to the low-order context and a context associated with another type; calculating coding probability information to be used in arithmetic coding of the binary signal, using (i) high-order probability information corresponding to the determined high-order context and (ii) low-order probability information corresponding to the determined low-order context; performing the arithmetic coding on the binary signal using the coding probability information; and updating the high-order probability information and the low-order probability information based on the binary signal.

主权项

1. An image coding method for performing compression-coding on pixel image data, said image coding method comprising:
binarizing a signal to be coded of the pixel image data, to generate a binary signal; determining a first low-order context, wherein the first low-order context is associated with a type of the signal to be coded; determining a first high-order context that is common to the first low-order context and at least one second low-order context which is other than the first low-order context, wherein the second low-order context is associated with another type of a signal; calculating coding probability information to be used in arithmetic coding of the binary signal, using first high-order probability information corresponding to the determined first high-order context and first low-order probability information corresponding to the determined first low-order context; performing the arithmetic coding on the binary signal using the calculated coding probability information; and updating the first high-order probability information and the first low-order probability information based on the binary signal.