Encoding method, comprising: determining a sub-list from a list of coefficients of a quantized residual block, the sub-list containing coefficients that are liable to be modified by identifying a first non-zero coefficient and the last non-zero coefficient, wherein the zero coefficients located before the first non-zero coefficient and the zero coefficients located after the last non-zero coefficient are liable to be modified; comparing a number of modifiable coefficients with a predetermined threshold of four; if the number of modifiable coefficients is lower than or equal to the threshold of four, the coefficients of the list are encoded, the entropy encoding comprising a sign of each non-zero coefficient in the list; if the number of modifiable coefficients is higher than the threshold of four, a value of the parity of the sum of the coefficients in the sub-list is calculated; verifying whether a single sign that is intended to be hidden corresponds to the parity of the sum of the coefficients in the sub-list according to a convention, wherein: if the sign is positive and the sum of the coefficients in the sub-list is even, the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; if the sign is negative and if the sum of the coefficients in the sub-list is odd, the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; if the sign is positive and the sum of the coefficients in the sub-list is odd, at least one modifiable coefficient in the sub-list is modified and the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; and if the sign is negative and the sum of the coefficients in the sub-list is even, at least one modifiable coefficient in the sub-list is modified and the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients, and wherein the sign of the first non-zero coefficient is intended to be hidden. determining a sub-list from a list of coefficients of a quantized residual block, the sub-list containing coefficients that are liable to be modified by identifying a first non-zero coefficient and the last non-zero coefficient, wherein the zero coefficients located before the first non-zero coefficient and the zero coefficients located after the last non-zero coefficient are liable to be modified; comparing a number of modifiable coefficients with a predetermined threshold of four; if the number of modifiable coefficients is lower than or equal to the threshold of four, the coefficients of the list are encoded, the entropy encoding comprising a sign of each non-zero coefficient in the list; if the number of modifiable coefficients is higher than the threshold of four, a value of the parity of the sum of the coefficients in the sub-list is calculated; verifying whether a single sign that is intended to be hidden corresponds to the parity of the sum of the coefficients in the sub-list according to a convention, wherein: if the sign is positive and the sum of the coefficients in the sub-list is even, the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; if the sign is negative and if the sum of the coefficients in the sub-list is odd, the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; if the sign is positive and the sum of the coefficients in the sub-list is odd, at least one modifiable coefficient in the sub-list is modified and the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; and if the sign is negative and the sum of the coefficients in the sub-list is even, at least one modifiable coefficient in the sub-list is modified and the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients, if the sign is positive and the sum of the coefficients in the sub-list is even, the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; if the sign is negative and if the sum of the coefficients in the sub-list is odd, the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; if the sign is positive and the sum of the coefficients in the sub-list is odd, at least one modifiable coefficient in the sub-list is modified and the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients; and if the sign is negative and the sum of the coefficients in the sub-list is even, at least one modifiable coefficient in the sub-list is modified and the coefficients in the list are encoded with the exception of the sign of the coefficient which is hidden in the parity of the sum of the coefficients, and wherein the sign of the first non-zero coefficient is intended to be hidden.