Clear-Vision is a Japanese EDTV (Extended Definition TV)[1][2] television system introduced in the 1990s, that improves audio and video quality while remaining compatible with the existing broadcast standard.
[5] The initial version of the system was called IDTV[5] (Improved Definition Television,[6] or SuperNTSC[7]) and was based on advanced signal processing on TV receivers.
This allowed improvements such as progressive scan, ghost cancellation (reducing the effects of multipath propagation) and NTSC luminance and chroma crosstalk reduction (by way of filtering),[6] without requiring any extra information being broadcast.
[8][16][17][5][2] The standard was published as ARIB STD-B9 - "Direct Coding for EDTV-II Television Signal" in 1997[18] and as ITU BT.1298 - "Enhanced wide-screen NTSC TV transmission system".
[9] EDTV-II broadcasts are displayed in letterbox format (with black bands on the top and bottom of the screen)[14] on regular 4:3 NTSC receivers with no decoding ability.