A versatile video coding (VVC) method includes obtaining a plurality of video sources; encoding the plurality of video sources into a bitstream including a plurality of independent layers corresponding to the plurality of video sources; generating signaling information on the plurality of independent layers and integrating the signaling information with the bitstream; and transferring the bitstream for decoding processing, wherein the signaling information is to be used in the decoding process to enable a single decoder instance to decode the plurality of independent layers similar to a single-layer bitstream. The signaling information includes at least a video parameter set (VPS), and the VPS includes a flag inbl_one_pic_per_poc_flag equal to 1, which specifies that the bitstream contains independent layers and there is one and only one coded picture with a particular picture order count (POC) value in a same coded video sequence (CVS) among all layers.