An HD Primer
iMovie HD actually supports a comparatively low-end variety of high-definition video called HDV, which is high-definition footage with MPEG-2 compression applied to it. HDV comes in two varieties, both of which iMovie HD supports: 1080i provides 1,920-by-1,080-pixel interlaced resolution, while 720p offers 1,280-by-720-pixel progressive-scan resolution. (The Sony Handycam HDR-FX1 camcorder on the right is a 1080i model.) Although it’s highly compressed, HDV currently offers more than enough image detail and sharpness for most nonprofessional editors.