recorded television programming. Most or all of the base PVR functionality becomes available by default at little or no added cost. MPEG4 and 4:2:2 Most standard FTA receivers support DVB-S, MPEG-2, 480i or 576i SDTV received as unencrypted QPSK from Ku band satellites. Rarely supported by stand-alone FTA receivers, but likely to be supported by FTA DVB-S tuners for personal computers, are MPEG-4 and MPEG2 4:2:2, variants on the MPEG compression algorithm which provide more compression and more colour resolution, respectively. As personal computers handle much of the video decompression in software, any codec could be easily substituted on the desktop. High-definition television is also beginning to be supported by a limited-number of high-end receivers; at least one high-end stand-alone receiver (the Quali-TV 1080IR) supports both 4:2:2 and HDTV. 4:2:2 is a version of MPEG-2 compression used in network feeds such as NBC on Ku band (103°W). Some broadcast networks use 4:2:2 encoding for otherwise-unencrypted transmission of sports events to local terrestrial stations, as it provides slightly better colour than the standard 4:2:0 compression. In some cases support for additional standards (such as DVB-S2, MPEG-4 and 8PSK) will also become necessary to receive a viewable signal. The use of newer means of modulation and compression is likely to become more widespread for high-definition television feeds, to partially offset the larger amount of transponder space required to deliver high-definition video to television stations. Terrestrial DTV In countries using the DVB-T and DVB-C standards for terrestrial digital television and digital cable, a few higher-end receivers provide an option to install terrestrial DVB tuners either alongside or in place of the stock DVB-S tuner. Dream Multimedia's DreamBox series, for instance, supports this in a few selected models. In countries using ATSC, inclusion of terrestrial tuners in DVB-S FTA receivers is rare, with one key exception. Some HDTV FTA receivers incorporate terrestrial ATSC tuners. These typically do not support ATSC's unique major.minor digital subchannel numbering scheme or the on-screen program guide but are capable of displaying (or timeshifting) local HDTV with no loss in detail. Channels from these receivers are numbered using FTA conventions, by which the first channel found is most often arbitrarily given channel 1 as its virtual channel number. HDTV A few high-end receivers feature HDTV. In North America, these often include an ATSC over-the-air digital television tuner and MPEG-4 support. A few HDTV units allow for the addition of a