Video decoder configured to decode a multi-layered data stream into which a video material is coded at different layers, corresponding to different levels of information amount, using inter-layer prediction, the multi-layer data stream comprising a plurality of packets, each of which is associated with one of the different layers, the video decoder configured to: for each of the packets of the multi-layered data stream, read a base layer-ID field from the multi-layered data stream, the base layer-ID field comprising a first sub-field and a second sub-field; check as to whether the first sub-field of the base layer-ID field fulfills a predetermined criterion, if the first sub-field of the base layer-ID field fulfills the predetermined criterion, read an extension layer-ID field from the multi-layered data stream, derive an extension value using the extension layer-ID field so that the extension value lies within a first subset of a domain of extension values, and derive a cluster value from the second sub-field by mapping from a domain of possible values of the second sub-field onto a domain of cluster values; if the first sub-field of the base layer-ID field does not fulfill the predetermined criterion, refrain from reading an extension layer-ID field from the multi-layered data stream, set the extension value to a value disjoint to the first subset of the domain of extension values, and derive the cluster value from the second sub-field by mapping from the domain of possible values of the second sub-field onto the domain of cluster values, index the layer which the respective packet is associated with using the cluster and extension values; wherein the video decoder is configured to index the layer which the respective packet is associated with, by concatenating the cluster and extension values. for each of the packets of the multi-layered data stream, read a base layer-ID field from the multi-layered data stream, the base layer-ID field comprising a first sub-field and a second sub-field; check as to whether the first sub-field of the base layer-ID field fulfills a predetermined criterion, if the first sub-field of the base layer-ID field fulfills the predetermined criterion, read an extension layer-ID field from the multi-layered data stream, derive an extension value using the extension layer-ID field so that the extension value lies within a first subset of a domain of extension values, and derive a cluster value from the second sub-field by mapping from a domain of possible values of the second sub-field onto a domain of cluster values; if the first sub-field of the base layer-ID field does not fulfill the predetermined criterion, refrain from reading an extension layer-ID field from the multi-layered data stream, set the extension value to a value disjoint to the first subset of the domain of extension values, and derive the cluster value from the second sub-field by mapping from the domain of possible values of the second sub-field onto the domain of cluster values, index the layer which the respective packet is associated with using the cluster and extension values; read a base layer-ID field from the multi-layered data stream, the base layer-ID field comprising a first sub-field and a second sub-field; check as to whether the first sub-field of the base layer-ID field fulfills a predetermined criterion, if the first sub-field of the base layer-ID field fulfills the predetermined criterion, read an extension layer-ID field from the multi-layered data stream, derive an extension value using the extension layer-ID field so that the extension value lies within a first subset of a domain of extension values, and derive a cluster value from the second sub-field by mapping from a domain of possible values of the second sub-field onto a domain of cluster values; if the first sub-field of the base layer-ID field does not fulfill the predetermined criterion, refrain from reading an extension layer-ID field from the multi-layered data stream, set the extension value to a value disjoint to the first subset of the domain of extension values, and derive the cluster value from the second sub-field by mapping from the domain of possible values of the second sub-field onto the domain of cluster values, index the layer which the respective packet is associated with using the cluster and extension values; wherein the video decoder is configured to index the layer which the respective packet is associated with, by concatenating the cluster and extension values.