1. A method for decoding coded pictures, comprising the steps of: parsing a bitstream including coded pictures to obtain split-flags for generating a transform tree, and a partitioning of coding units (CUs) into Prediction Units (PUs); generating the transform tree according to the split-flags, wherein nodes in the transform tree represent transform units (TUs) associated with the CUs, wherein the generating further comprises; splitting each TUs only if the split-flag is set; modifying the transform tree according to the splitting; and decoding data contained in each PU using the TUs associated with the PU according to the transform tree, wherein the steps are performed in a processor.