What Is the NTSC DVD Format?by Nick Miles
NTSC is a video format developed by the National Television System Committee. It is a standard that was used for broadcasting over-the-air signals as well as displaying DVD video. While the broadcasting has been replaced by the ATSC format, the NTSC format still remains in DVDs. The NTSC format differs from the PAL format that is used in other countries.
The standard NTSC resolution is 720 x 480. When displaced interlaced, this is referred to as standard definition 480i. When displayed with progressive scan, this is referred to as enhanced definition 480p. All modern DVD players as well as Blu-ray players that play DVDs feature progressive scan technology, but many older DVD players do not.
The frame rate for the NTSC standard is 30 frames per second. On NTSC DVDs the frame rate is effectively 29.97 fps. It is slowed down slightly in order to keep the audio in sync. This differs from the 24 fps that movies are shot in.
Since all movies are shot at 24 fps, the video must be converted in order to be displayed in the NTSC format. This is accomplished via the 3:2 pulldown. Essentially what the 3:2 pulldown does is convert four frames of film to five frames of video in order to change the frame rate from 24 to 30. Odd frames are split into two fields while even frames are split into three fields and the result is then displayed two fields at a time at 30 frames per second.
The NTSC format is only used in certain countries that have adopted the NTSC format. This include the United States, Canada, and Japan. Other countries, such as Australia, China, and most of Europe, use the PAL standard.
The PAL standard differs slightly from NTSC. PAL resolution is 720 x 576 while the frame rate is 25 frames per second. With a 25 fps frame rate, film that has to be formatted for PAL must be sped up by 4 percent and the audio must be synced. While the two formats are mostly incompatible, most PAL DVD players can play NTSC DVDs. The same cannot be said for NTSC DVD players, although some can and there are external PAL converters that can do the job.