1. A method of determining decoding relationship for a coded multi-layer video stream defining multiple layers of pictures, said method comprises: retrieving, based on said coded multi-layer video stream, at least one direct decoding flag indicating a direct coding relationship between a layer with layer index i of said multiple layers and a layer with layer index j of said multiple layers, wherein i≠j, wherein retrieving said at least one direct decoding flag comprises retrieving, for said layer with layer index i, a respective direct dependency flag for each layer index j based on said coded multi-layer video stream, wherein j<i and said direct dependency flag indicates whether said layer with layer index j is a direct reference layer for said layer with layer index i; determining information defining both an indirect decoding relationship and a direct decoding relationship between said multiple layers based on said at least one direct decoding flag, wherein determining said information comprises determining information defining any layer with layer index j<i which said layer with layer index i depends on, based on said direct dependency flags; and determining a type of prediction operation based on at least one scalability identifier of said layer with layer index i and at least one scalability identifier of said layer with layer index j.