Method of coding and decoding images, coding and decoding device and computer programs corresponding thereto

A decoder comprising:

• one or more processors and one or more storage devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:
• receiving a data stream representative of a coded image;
• identifying, in the data stream, a plurality of rows of consecutive blocks of quantized coefficients of transformed residual values for the coded image;
• initializing one or more state variables for entropy decoding a current block in a current row of the plurality of rows;
• entropy decoding the current block based on the one or more state variables for entropy decoding the current block;
• wherein when the current block is a first block in the current row in a decoding order for decoding the coded image and the current row is not the first row of the plurality of rows in the decoding order, the one or more state variables for decoding the current block are initialized based on one or more state variables of a predetermined entropy decoded block;
• and
• wherein the predetermined entropy decoded block is a second block in the decoding order in a row of consecutive blocks other than the current row.

A non-transitory computer-readable medium coupled to one or more processors having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations comprising:

• receiving a data stream representative of a coded image;
• identifying, in the data stream, a plurality of rows of consecutive blocks of quantized coefficients of transformed residual values for the coded image;
• initializing one or more state variables for entropy decoding a current block in a current row of the plurality of rows;
• entropy decoding the current block based on the one or more state variables for entropy decoding the current block;
• wherein when the current block is a first block in the current row in a decoding order for decoding the coded image and the current row is not the first row of the plurality of rows in the decoding order, the one or more state variables for decoding the current block are initialized based on one or more state variables of a predetermined entropy decoded block;
• and
• wherein the predetermined entropy decoded block is a second block in the decoding order in a row of consecutive blocks other than the current row.