To identify data losses in a video sequence transmitted between a server and at least one client over a communication network, the sequence comprising a plurality of video data containers coded using scalable video coding employing a predetermined number of hierarchical levels, the video data containers being transmitted over the network via a series of data transport packets: a process (311) is carried out of detecting losses and of locating the video data affected by those losses, without decoding the video data, by combining information coming from transport packets and information coming from video data container headers.Application for improving decoding on receiving a video sequence.