Contents

1 Analog (stereo) audio cable [4]

• History: The audio amplifier was invented in 1909 by Lee De Forest when he invented the triode vacuum tube. Probably, the first audio link was used also in this moment.
• Medium: Usually, a two copper parallel wires o a coaxial cable per channel, with RCA (Radio Corporation of America) connectors.
• Bit-rate: Not applicable.
• Content aware: No.

2 S/PDIF (Sony/Philips Digital Interconnect Format) [5]

• History: Sony and Philips produced S/PDIF format in mid-1980. Its aim was to connect digital audio devices via a digital connection.
• Medium: Coaxial cable with RCA connectors or a fiber optic cable with TOSLINK connectors.
• Bit-rate: 6,144 Mbps.
• Content aware: Two channels of uncompressed lossless PCM audio or compressed 5.1/7.1 surround sound (such as Dolby Digital Plus or DTS-HD High Resolution Audio); it cannot support uncompressed lossless formats (such as Dolby TrueHD and DTS-HD Master Audio) which require much greater bit-rate.

3 VGA (Video Graphics Array) (D-sub15) [6]

• History: Designed by IBM in 1987.
• Medium: 15 copper wires.
• Bit-rate: Not applicable.
• Content aware: No. Analog RGB video. Up to 2048 × 1536 (QXGA) @ 85 Hz (388 MHz).

4 DVI (Digital Visual Interface) [1]

• History: Developed by the Digital Display Working Group (Intel Corporation, Silicon Image, Inc., Compaq Computer Corp., Fujitsu Limited, Hewlett-Packard Company, International Business Machines Corp. and NEC Corporation.) in 1999.
• Medium: 29 copper wires.
• Bit-rate: 3.96 Gbps.
• Content aware: No. RGB video.

5 HDMI (High-Definition Multimedia Interface) [3]

• History: The HDMI Founders (Hitachi, Matsushita Electric Industrial (Panasonic/National/Quasar), Philips, Silicon Image, Sony, Thomson, RCA and Toshiba) began development on HDMI 1.0 on April 16, 2002, with the goal of creating an AV connector that was backward-compatible with DVI. The first authorized testing center, which tests HDMI products, was opened by Silicon Image on June 23, 2003, in California, United States.
• Medium: An HDMI cable is usually composed of four shielded twisted pairs, with impedance of the order of 100Ω, plus several separate conductors.
• Bit-rate: 1.65 Gbps (1.0, 1.1 and 1.2), 3.4 Gbps (1.3 and 1.4), 6.0 Gbps (2.0).
• Content aware:
  • Audio: Yes. Up to 8 PCM channels, 16, 20 and 24 bits/sample, 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz and 192 kHz. Dolby Digital, DTS, Super Audio CD, Dolby TrueHD and DTS-HD Master Audio.
  • Video: No (being digital). sRGB, YCbCr, xvYCC space colors and up to 4096 × 2160 (4K) 60 Hz progressive.

6 DisplayPort [2]

• History: Developed in 2006 by the VESA (Video Electronics Standards Association).
• Medium: 20 copper wires.
• Bit-rate: 4.608 Mbps (audio) + 21.39 Gbps (video).
• Content aware:
  1. Audio: Yes. 8 channel PCM audio up to 24 bits/sample and 192 kHz/channel and audio compression formats.
  2. Video: Uncompressed RGB/YCbCr video, up to 3840 × 2160 × 30 bpp @ 60 Hz.

References