Standard media players and converters typically do not support Panasonic's proprietary N3R format and you have to rely on software provided by the company for playback and conversion of this video format.
As far as we know, the WV-ASM200 software from Panasonic should be able to convert .n3r videos to standard MPEG-4 video format (.mp4). But perhaps there are other similar programs from the company that can help you with n3r to mp4 conversion or something similar.