A method implemented by a decoder, the method comprising: receiving, by the decoder, a sub-bitstream comprising a sequence parameter set, SPS, and a coded picture, wherein the SPS includes a SPS video parameter set identifier, sps_video_parameter_set_id, wherein the coded picture is in a set of video coding layer, VCL, network abstraction layer, NAL, units associated with a layer having a NAL unit header layer identifier, nuh layer id, and wherein the sub-bitstream is obtained by a sub-bitstream extraction process performed on a multi-layer bitstream, the sub-bitstream extraction process being a process by which NAL units in the multi-layer bitstream that do not belong to a specified target set are removed from the multi-layer bitstream such that the sub-bitstream comprises the NAL units that belong the target set; wherein the sps_video_parameter_set_id specifies a value of a VPS parameter set identifier, vps_video_parameter_set_id, when greater than zero; the SPS does not refer to a VPS and no VPS is referred to when decoding each coded layer video sequence referring to the SPS when the sps_video_parameter_set_id is equal to zero; setting, by the decoder, a general layer index corresponding to the nuh_layer_id, GeneralLayerIdx[nuh_layer_id], equal to zero when the sps video_parameter_set_id is equal to zero, wherein GeneralLayerIdx[nuh_layer_id] is equal to a current layer index; inferring, by the decoder, that a value of a video parameter set, VPS, independent layer flag for the GeneralLayerIdx[nuh_layer_id], vps_independent_layer_flag[GeneralLayerIdx[ nuh_layer_id]], is equal to one when sps_video_parameter_set_id is equal to zero; vps _independent layer flag [GeneralLayerIdx[nuh_layer_id]] specifying that the layer with index GeneralLayerIdx[ nuh_layer_id] does not use inter-layer prediction when having a value equal to one; and decoding, by the decoder, the coded picture from the VCL NAL units based on the GeneralLayerIdx[nuh_layer_id] to produce a decoded picture. receiving, by the decoder, a sub-bitstream comprising a sequence parameter set, SPS, and a coded picture, wherein the SPS includes a SPS video parameter set identifier, sps_video_parameter_set_id, wherein the coded picture is in a set of video coding layer, VCL, network abstraction layer, NAL, units associated with a layer having a NAL unit header layer identifier, nuh layer id, and wherein the sub-bitstream is obtained by a sub-bitstream extraction process performed on a multi-layer bitstream, the sub-bitstream extraction process being a process by which NAL units in the multi-layer bitstream that do not belong to a specified target set are removed from the multi-layer bitstream such that the sub-bitstream comprises the NAL units that belong the target set; wherein the sps_video_parameter_set_id specifies a value of a VPS parameter set identifier, vps_video_parameter_set_id, when greater than zero; the SPS does not refer to a VPS and no VPS is referred to when decoding each coded layer video sequence referring to the SPS when the sps_video_parameter_set_id is equal to zero; setting, by the decoder, a general layer index corresponding to the nuh_layer_id, GeneralLayerIdx[nuh_layer_id], equal to zero when the sps video_parameter_set_id is equal to zero, wherein GeneralLayerIdx[nuh_layer_id] is equal to a current layer index; inferring, by the decoder, that a value of a video parameter set, VPS, independent layer flag for the GeneralLayerIdx[nuh_layer_id], vps_independent_layer_flag[GeneralLayerIdx[ nuh_layer_id]], is equal to one when sps_video_parameter_set_id is equal to zero; vps _independent layer flag [GeneralLayerIdx[nuh_layer_id]] specifying that the layer with index GeneralLayerIdx[ nuh_layer_id] does not use inter-layer prediction when having a value equal to one; and decoding, by the decoder, the coded picture from the VCL NAL units based on the GeneralLayerIdx[nuh_layer_id] to produce a decoded picture.