Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data. This is in contrast to analog video, which represents moving visual images in the form of analog signals. Digital video comprises a series of digital images displayed in rapid succession, usually at 24, 30, or 60 frames per second. Digital video has many advantages such as easy copying, multicasting, sharing and storage.
Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic tape could with relative ease record and playback audio, visual, and binary computer data.
Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems which, in turn, were replaced by flat panel displays of several types.
DV refers to a family of codecs and tape formats used for storing digital video, launched in 1995 by a consortium of video camera manufacturers led by Sony and Panasonic. In the late 1990s and early 2000s, DV was strongly associated with the transition from analog to digital desktop video production, and also with several enduring "prosumer" camera designs such as the Sony VX-1000. DV is sometimes referred to as MiniDV, which was the most popular tape format using a DV codec during this time.
Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocassette recorders (VCRs) and camcorders. Videotapes have also been used for storing scientific or medical data, such as the data produced by an electrocardiogram.
S-VHS (スーパー・ヴィエイチエス), the common initialism for Super VHS, is an improved version of the VHS standard for consumer-level video recording. Victor Company of Japan introduced S-VHS in Japan in April 1987, with their JVC-branded HR-S7000 VCR, and in certain overseas markets soon afterward. By the end of 1987, the first S-VHS VCR models from other competitors included Hitachi VT-2700A, Mitsubishi HS-423UR, Panasonic PV-S4764, RCA VPT-695HF, and Toshiba SV-950. It has been standardized as IEC 60774-3 and IEC 60774-4.
Betamax is a consumer-level analog recording and cassette format of magnetic tape for video, commonly known as a video cassette recorder. It was developed by Sony and was released in Japan on May 10, 1975, followed by the US in November of the same year.
D-1 or 4:2:2 Component Digital is an SMPTE digital recording video standard, introduced in 1986 through efforts by SMPTE engineering committees. It started as a Sony and Bosch - BTS product and was the first major professional digital video format. SMPTE standardized the format within ITU-R 601, also known as Rec. 601, which was derived from SMPTE 125M and EBU 3246-E standards.
A camcorder is a self-contained portable electronic device with video and recording as its primary function. It is typically equipped with an articulating screen mounted on the left side, a belt to facilitate holding on the right side, hot-swappable battery facing towards the user, hot-swappable recording media, and an internally contained quiet optical zoom lens.
Betacam is a family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, "Betacam" singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself.
A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material from magnetic tape. The early VTRs were open-reel devices that record on individual reels of 2-inch-wide (5.08 cm) tape. They were used in television studios, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. Beginning in 1963, videotape machines made instant replay during televised sporting events possible. Improved formats, in which the tape was contained inside a videocassette, were introduced around 1969; the machines which play them are called videocassette recorders.
Serial digital interface (SDI) is a family of digital video interfaces first standardized by SMPTE in 1989. For example, ITU-R BT.656 and SMPTE 259M define digital video interfaces used for broadcast-grade video. A related standard, known as high-definition serial digital interface (HD-SDI), is standardized in SMPTE 292M; this provides a nominal data rate of 1.485 Gbit/s.
D-5 is a professional digital video format introduced by Panasonic at 18th International Television Symposium in Montreux in 1993 and launched a year later in 1994. Like Sony's D-1 (8-bit), it is an uncompressed digital component system (10-bit), but uses the same half-inch tapes as Panasonic's digital composite D-3 format. A 120 min. D-3 tape will record 60 min. in D-5/D-5 HD mode. D-5 standard definition (SD) decks can be retrofitted to record high definition with the use of an external HD input/output box/decoder. There were native D5 HD decks as well that didn't need an external processor and could record in both SD and HD. High definition conversion on D5 HD decks does not allow for any error correction that exists on standard definition recordings, as the full bandwidth of the tape is required for high definition recording.
HDV is a format for recording of high-definition video on DV videocassette tape. The format was originally developed by JVC and supported by Sony, Canon, and Sharp. The four companies formed the HDV Consortium in September 2003.
U-matic or 3⁄4-inch Type E Helical Scan or SMPTE E is an analogue recording videocassette format first shown by Sony in prototype in October 1969, and introduced to the market in September 1971. It was among the first video formats to contain the videotape inside a cassette, as opposed to the various reel-to-reel or open-reel formats of the time. The videotape is 3⁄4 in (19 mm) wide, so the format is often known as "three-quarter-inch" or simply "three-quarter", compared to open reel videotape formats in use, such as 1 in (25 mm) type C videotape and 2 in (51 mm) quadruplex videotape.
D-VHS is a digital video recording format developed by JVC, in collaboration with Hitachi, Matsushita, and Philips. The "D" in D-VHS originally stood for "Data", but JVC renamed the format as "Digital VHS". Released in December of 1997, it uses the same physical cassette format and recording mechanism as S-VHS, but requires higher-quality and more expensive tapes and is capable of recording and displaying both standard-definition and high-definition content. The content data format is in MPEG transport stream, the same data format used for most digital television applications. It used MPEG-2 encoding and was standarized as IEC 60774-5.
XDCAM is a series of products for digital recording using random access solid-state memory media, introduced by Sony in 2003. Four different product lines – the XDCAM SD, XDCAM HD, XDCAM EX and XDCAM HD422 – differ in types of encoder used, frame size, container type and in recording media.
HDCAM is a high-definition video digital recording videocassette version of Digital Betacam introduced in 1997 that uses an 8-bit discrete cosine transform (DCT) compressed 3:1:1 recording, in 1080i-compatible down-sampled resolution of 1440×1080, and adding 24p and 23.976 progressive segmented frame (PsF) modes to later models. The HDCAM codec uses rectangular pixels and as such the recorded 1440×1080 content is upsampled to 1920×1080 on playback. The recorded video bit rate is 144 Mbit/s. Audio is also similar, with four channels of AES3 20-bit, 48 kHz digital audio. Like Betacam, HDCAM tapes were produced in small and large cassette sizes; the small cassette uses the same form factor as the original Betamax. The main competitor to HDCAM was the DVCPRO HD format offered by Panasonic, which uses a similar compression scheme and bit rates ranging from 40 Mbit/s to 100 Mbit/s depending on frame rate.
The first attempt at producing pre-recorded HDTV media was a scarce Japanese analog MUSE-encoded laser disc which is no longer produced.
D6 HDTV VTR is SMPTE videocassette standard. A D6 VTR can record and playback HDTV video uncompressed. The only D6 VTR product is the Philips, now Thomson's Grass Valley's Media Recorder, model DCR 6024, also called the D6 Voodoo VTR. The VTR was a joint project between Philips Digital Video Systems of Germany and Toshiba in Japan. The tape deck module was designed and made by Philips in Weiterstadt, Germany, and the digital processor module designed and made by Toshiba. Since there is no data compression, after 20 tape copies of multi generations there is no noticeable loss of quality. As a very high-end, costly system about 70 were sold to high-end post houses from about 2000 to 2005. The VTR had a data record option. The data module could record and play back 2k DPX files at 6 frames per second over a HIPPI connection. The VTR came in a data only model, or with a switch module, so the record deck could be used for both video and data recording. The tape deck was also sold stand alone as a giga bit recorder to record and playback raw data. Toshiba made the video tape for the VTR. The high price of the video tape limited the use of the VTR.
