The invention relates to a computer-implemented method for providing a data stream comprising a plurality of content elements. At least one of two or more copies of a first content element of the data stream has been watermarked with a different watermark. The method includes watermarking at least one of two or more copies of a second content element with a different watermark. In a rendering order of the data stream, the second content element is at an interval equal to or greater than a watermark interval from the first content element. The watermark interval is set to be sufficiently long so that the output quality of the rendered data stream can either completely recover or at least return to a predetermined acceptable level following the watermarking of the copies of the first content element before watermarking the copies of the next content element.