ATSC

ATSC Standards document a digital television format which will replace (in the United States) the analog NTSC television system (NTSC is used mostly in North America and Japan). It was developed by the Advanced Television Systems Committee.The high definition television standards defined by the ATSC produce wide screen 16:9 images up to 1920×1080 pixels in size — more than six times the  display resolution of the earlier standard. However, a host of different image sizes are also supported, so that up to six standard-definition "virtual channels" can be broadcast on a single TV station using the existing 6 MHz channel.
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