 [I, P][4:2:0][1], and the highest one, called HP, by [I, P, B][4:2:2][1-3]; Level, through (a) the number of pixels per line [325 to 1920], (b) the number of lines [288 to 1152], at a rate of 30 frames per second. The lowest level, called LL, is [352][288], and the highest one, called HL, is [1920][1152]. Profile@level, through (a) the 2D motion-picture pixel resolution [176 X 144 to 1920 X 1080 with many intermediate variants], (b) the frame rate [15 to 60], (c) the sampling [4:2:0 or 4:2:2], and (d) the bit rate [0.096 to 300 Mbit/s]. The lowest option, called SP@LL, is, thus, [176 X 144][15][4:2:0][0.096], while the high- est one (a potential for future applications), called 422P@HL, is either [1920 X 1080][30][4:2:2][300] or [1280 X 720][60][4:2:2][300]. 43 See, for instance: http://en.wikipedia.org/wiki/MPEG-2. Overview of data compression standards It is clear that each of the standard profile@level options has been designed to meet spe- cific consumer-electronics applications and requirements, such as: wireless mobile hand- sets cellular telephony), personal digital assistants (PDA), set-top boxes (STB), dig- ital versatile disk (DVD), digital video broadcast (DVB), high-definition video (HDV), high-definition television (HDTV), and many other professional-imaging applications, present and future. A key application of MPEG-2, which is interesting to consider here an illustrative example, is the DVD. 44 As users know, commercial DVDs now come in several capacity options, including read-and-write versions (known as DVD R, DVD RW, DVD-RAM), 45 namely, 4.7/9.4 Gbytes (single-layer) and 8.5/17.1 Gbytes (double layer). The video channel has a variable bit rate that peaks at 9.8 Mbit/s, yielding a total bit rate (audio + video) varying between 300 kbit/s and 10.08 Mbit/s. A 4.7 Gbyte DVD can store movies with 90 - 120 min running times. MPEG-4 This is a format patented by ISO/IEC, which includes no less than 23 standards or "parts."46 These allow for audio and video compression enhancement and a wide range of no