A method for decoding a bitstream of coded scalable video comprising: receiving a bitstream of coded video including a base layer, one or more enhancement layers and a video parameter set comprising a scalability information about each layer, wherein the video parameter set includes: a flag which indicates whether scalability dimension identifiers are implicitly or explicitly signaled; and a maximum value of the scalability dimension identifiers for each scalability dimension from a plurality of scalability dimensions for each layer, wherein a presence or absence of the plurality of the scalability dimensions in the respective layer is indicated in a scalability mask signaled in the bitstream, wherein each scalability dimension identifier specifies the scalability dimension of each layer including the one or more enhancement layers and the base layer, the scalability dimension being one of multiple types including a spatial type and a quality type; determining based on the flag whether the scalability dimension identifiers are implicitly or explicitly signaled; decoding the bitstream of coded video using the base layer and the one or more enhancement layers, and inferring during the decoding and from a syntax element of a network abstraction layer unit header in the bitstream of coded video, one or more scalability dimension identifiers of a NAL unit, wherein the NAL unit corresponds to the NAL unit header, wherein in response to determining that the scalability dimension identifiers are implicitly signaled, said inferring is performed implicitly based on said maximum value of the scalability dimension identifiers and said syntax element. receiving a bitstream of coded video including a base layer, one or more enhancement layers and a video parameter set comprising a scalability information about each layer, wherein the video parameter set includes: a flag which indicates whether scalability dimension identifiers are implicitly or explicitly signaled; and a maximum value of the scalability dimension identifiers for each scalability dimension from a plurality of scalability dimensions for each layer, wherein a presence or absence of the plurality of the scalability dimensions in the respective layer is indicated in a scalability mask signaled in the bitstream, wherein each scalability dimension identifier specifies the scalability dimension of each layer including the one or more enhancement layers and the base layer, the scalability dimension being one of multiple types including a spatial type and a quality type; determining based on the flag whether the scalability dimension identifiers are implicitly or explicitly signaled; decoding the bitstream of coded video using the base layer and the one or more enhancement layers, and inferring during the decoding and from a syntax element of a network abstraction layer unit header in the bitstream of coded video, one or more scalability dimension identifiers of a NAL unit, wherein the NAL unit corresponds to the NAL unit header, wherein in response to determining that the scalability dimension identifiers are implicitly signaled, said inferring is performed implicitly based on said maximum value of the scalability dimension identifiers and said syntax element. a flag which indicates whether scalability dimension identifiers are implicitly or explicitly signaled; and a maximum value of the scalability dimension identifiers for each scalability dimension from a plurality of scalability dimensions for each layer, wherein a presence or absence of the plurality of the scalability dimensions in the respective layer is indicated in a scalability mask signaled in the bitstream, wherein each scalability dimension identifier specifies the scalability dimension of each layer including the one or more enhancement layers and the base layer, the scalability dimension being one of multiple types including a spatial type and a quality type; determining based on the flag whether the scalability dimension identifiers are implicitly or explicitly signaled; decoding the bitstream of coded video using the base layer and the one or more enhancement layers, and inferring during the decoding and from a syntax element of a network abstraction layer unit header in the bitstream of coded video, one or more scalability dimension identifiers of a NAL unit, wherein the NAL unit corresponds to the NAL unit header, wherein in response to determining that the scalability dimension identifiers are implicitly signaled, said inferring is performed implicitly based on said maximum value of the scalability dimension identifiers and said syntax element.