FIELD: information technology.
SUBSTANCE: first integrity check code which can be calculated at an encoder and then sent to a decoder as a supplemental optimisation information message is used. The decoder calculates a second integrity check code over the actual received network abstraction layer units (NAL), wherein the second integrity check code can be compared with the first encoder-generated first integrity check code sent via the supplemental optimisation information message to indicate if in fact all of the transmitted NAL units from which the integrity check code was generated have been received without changes in their content. In addition, an error tracking algorithm is provided which can be run at either the encoder or the decoder in order to determine if the network abstraction layer units are correct in content at the decoder side. Consequently, pictures which are sent only in form of intra-coded frames and pictures which are sent only in form of inter-coded frames can both be checked for errors.
EFFECT: tracking errors in situations when a decoder fails to provide the encoder with accurate information regarding actual decoded data.
33 cl, 5 dwg
