al Standards Organization (ISO) Motion Picture Experts Group (MPEG) MPEG-2specification. They derived scanning formats from computer-friendly progressive scanning and television-friendly interlaced scanning modes. The specification included MPEG-2 transport and compression technologies and quadrature amplitude modulation The History and Technology of Analog Video (QAM) or a variant, vestigial-sideband (VSB) modulation. The system specified Reed- Solomon Forward Error Correction (RSFC), which is common in CDs, hard drives, telephone modems, and digital transmission systems. Audio encoding was specified via six-channel, CD-quality digital surround sound. With the completion of a specification, the Grand Alliance (GA) began laboratory tests. They found VSB superior to QAM, and modified the specification accordingly. At the end of all their proof-of-concept testing, the GA documented their HDTV specification and submitted it to the ATSC for approval. On April 12, 1995, the ATSC approved the GA's Digital Television Standard for HDTV Transmission (formally known as ATSC A/53.) ATSC A/53 uses AT&T's and General Instrument's video encoder, Philips' decoder, Sarnoff/Thomson's transport subsystem and system integration expertise, and Zenith's modulation sub-system. In 1995, the computer industry belatedly noticed that ATSC A/53 was not computer- friendly. It was biased toward interlace scanning (as opposed to PC friendly progressive scanning), used an aspect ratio that was not compatible with computer monitors (16:9), and formatted pixels in an awkward fashion. In a last-minute effort to stop the FCC's final approval of ATSC A/53, Microsoft, Apple, Compaq, and others formed the Computer Industry Coalition for Advanced Television Service (CICATS.) CICATS led the charge against interlace, and submitted a standard based on the work of Gary Demos, a winner of an Oscar for technical excellence in filmmaking. Progressive scanning offers an observed resolution of about 70% of maximum vertical resolution because pixels fall betwee