XDCAM
Encyclopedia
XDCAM is a 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.
None of the later products have made earlier product lines obsolete. Sony maintains that different formats within XDCAM family have been designed to meet different applications and budget constraints.
The XDCAM range includes cameras and decks which act as drop-in replacements for traditional VTRs allowing XDCAM discs to be used within a traditional video tape-based workflow. These decks can also serve as random access
computer hard drives for easy import of the video data files into non-linear editing system
s (NLE) via FireWire (IEEE 1394) and Ethernet.
In September 2008, JVC
announced its alliance with Sony to support the XDCAM EX format.
In August 2009, Convergent Design began shipping the nanoFlash Portable Recorder, which uses the Sony XDCAM HD422 codec.
Video is recorded with DV
, MPEG-2 Part 2 or MPEG-4
compression schemes. DV is used for standard definition video, MPEG-2 is used both for standard and high definition video, while MPEG-4 is used for proxy video.
Audio is recorded in uncompressed PCM form for all formats except proxy video, which uses A-Law compression.
Equipment that uses Professional Disc as recording media employs MXF
container to store digital audio
/digital video
streams. Tapeless camcorder
s that record onto solid-state memory cards, use MP4 container for high definition audio/video, and DV-AVI container for DV video. JVC camcorders that use XDCAM EX recording format, are also capable of recording into QuickTime container besides using MP4 container.
encoding at data rate of 30, 40 or 50 Megabits per second. Unlike most other MPEG-2 implementations, IMX uses intraframe compression with each frame having the same exact size in bytes to simplify recording onto video tape. Sony claims that at 50 Mbit/s it offers visual quality that is comparable to Digital Betacam MPEG IMX is not supported in the XDCAM EX product line.
DVCAM uses standard DV
encoding, which runs at 25 Mbit/s, and is compatible with most editing systems. Some camcorders that allow DVCAM recording can record progressive-scan video.
MPEG HD is used in all product lines except for XDCAM SD. This format supports multiple frame sizes, frame rates, scanning types and quality modes. Depending on product line or a particular model, not all modes of this format may be available.
MPEG HD422 doubles the chroma-resolution compared to the previous generations of high-definition video
XDCAM formats. To accommodate the improved chroma detail, video bitrate has been increased to 50 Mbit/s. This format is used only in XDCAM HD422 products.
Proxy AV is used to record low resolution proxy videos. This format employs MPEG-4
video encoding at 1.5 Mbit/s (CIF
resolution) with 64 kbit/s (8 kHz A-law, ISDN Quality) for each audio channel.
1 720p @ 19 Mbit/s is offered by JVC and is equivalent to HDV 720p
The Professional Disc was chosen by Sony as its medium for professional non-linear video acquisition for a number of reasons, outlined in their white-paper Why Sony Adopted Professional Disc. This disc is similar to Blu-ray Disc
and holds either 23 GB of data (PFD23, single-layer, rewritable), 50 GB (PFD50, dual-layer, rewritable) or 128 GB (PFD128QLW, quad-layer, write-once).
Essentially the Professional Disc format was deemed to be a suitable, cost effective and easy step forward. The discs are reliable and robust, suitable for field work (something which has previously been a problem with many disc-based systems). Additionally, the cost of media is comparable to existing professional formats.
In 2008 Sony introduced a new recording medium to their XDCAM range – SxS Pro . It is a solid-state memory card implemented as an ExpressCard
module. The first camera to use this media was the Sony PMW-EX1 professional video camera
.
In December 2009, Sony introduced the more affordable SxS-1. This unit is designed to have the same performance as the SxS Pro card however its life expectancy is shorter at an estimated 5 years of life when used every day to the card's full capacity.
Secure Digital memory cards can be used in Sony XDCAM EX camcorders via the MEAD-SD01 adapter.
Digital recording
In digital recording, digital audio and digital video is directly recorded to a storage device as a stream of discrete numbers, representing the changes in air pressure for audio and chroma and luminance values for video through time, thus making an abstract template for the original sound or...
using random access
Random access
In computer science, random access is the ability to access an element at an arbitrary position in a sequence in equal time, independent of sequence size. The position is arbitrary in the sense that it is unpredictable, thus the use of the term "random" in "random access"...
solid-state memory media, introduced by Sony
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
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.
None of the later products have made earlier product lines obsolete. Sony maintains that different formats within XDCAM family have been designed to meet different applications and budget constraints.
The XDCAM range includes cameras and decks which act as drop-in replacements for traditional VTRs allowing XDCAM discs to be used within a traditional video tape-based workflow. These decks can also serve as random access
Random access
In computer science, random access is the ability to access an element at an arbitrary position in a sequence in equal time, independent of sequence size. The position is arbitrary in the sense that it is unpredictable, thus the use of the term "random" in "random access"...
computer hard drives for easy import of the video data files into non-linear editing system
Non-linear editing system
In video, a non-linear editing system is a video editing or audio editing digital audio workstation system which can perform random access non-destructive editing on the source material...
s (NLE) via FireWire (IEEE 1394) and Ethernet.
In September 2008, JVC
JVC
, usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...
announced its alliance with Sony to support the XDCAM EX format.
In August 2009, Convergent Design began shipping the nanoFlash Portable Recorder, which uses the Sony XDCAM HD422 codec.
Compression methods
The XDCAM format uses multiple video compression methods and media container formats.Video is recorded with DV
DV
DV is a format for the digital recording and playing back of digital video. The DV codec was launched in 1995 with joint efforts of leading producers of video camcorders....
, MPEG-2 Part 2 or MPEG-4
MPEG-4
MPEG-4 is a method of defining compression of audio and visual digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group under the formal standard ISO/IEC...
compression schemes. DV is used for standard definition video, MPEG-2 is used both for standard and high definition video, while MPEG-4 is used for proxy video.
Audio is recorded in uncompressed PCM form for all formats except proxy video, which uses A-Law compression.
Equipment that uses Professional Disc as recording media employs MXF
MXF
Material eXchange Format is a container format for professional digital video and audio media defined by a set of SMPTE standards.- A brief summary of MXF :...
container to store digital audio
Digital audio
Digital audio is sound reproduction using pulse-code modulation and digital signals. Digital audio systems include analog-to-digital conversion , digital-to-analog conversion , digital storage, processing and transmission components...
/digital video
Digital video
Digital video is a type of digital recording system that works by using a digital rather than an analog video signal.The terms camera, video camera, and camcorder are used interchangeably in this article.- History :...
streams. Tapeless camcorder
Tapeless Camcorder
A tapeless camcorder is a camcorder that does not use video tape for the digital recording of video productions as 20th century ones did. Tapeless camcorders record video as digital computer files onto random access data storage devices such as optical discs, hard disk drives and solid-state flash...
s that record onto solid-state memory cards, use MP4 container for high definition audio/video, and DV-AVI container for DV video. JVC camcorders that use XDCAM EX recording format, are also capable of recording into QuickTime container besides using MP4 container.
Recording formats
MPEG IMX allows recording in standard definition, using MPEG-2MPEG-2
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
encoding at data rate of 30, 40 or 50 Megabits per second. Unlike most other MPEG-2 implementations, IMX uses intraframe compression with each frame having the same exact size in bytes to simplify recording onto video tape. Sony claims that at 50 Mbit/s it offers visual quality that is comparable to Digital Betacam MPEG IMX is not supported in the XDCAM EX product line.
DVCAM uses standard DV
DV
DV is a format for the digital recording and playing back of digital video. The DV codec was launched in 1995 with joint efforts of leading producers of video camcorders....
encoding, which runs at 25 Mbit/s, and is compatible with most editing systems. Some camcorders that allow DVCAM recording can record progressive-scan video.
MPEG HD is used in all product lines except for XDCAM SD. This format supports multiple frame sizes, frame rates, scanning types and quality modes. Depending on product line or a particular model, not all modes of this format may be available.
MPEG HD422 doubles the chroma-resolution compared to the previous generations of high-definition video
High-definition video
High-definition video or HD video refers to any video system of higher resolution than standard-definition video, and most commonly involves display resolutions of 1,280×720 pixels or 1,920×1,080 pixels...
XDCAM formats. To accommodate the improved chroma detail, video bitrate has been increased to 50 Mbit/s. This format is used only in XDCAM HD422 products.
Proxy AV is used to record low resolution proxy videos. This format employs MPEG-4
MPEG-4
MPEG-4 is a method of defining compression of audio and visual digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group under the formal standard ISO/IEC...
video encoding at 1.5 Mbit/s (CIF
Common Intermediate Format
CIF , also known as FCIF , is a format used to standardize the horizontal and vertical resolutions in pixels of YCbCr sequences in video signals, commonly used in video teleconferencing systems. It was first proposed in the H.261 standard.CIF was designed to be easy to convert to PAL or NTSC...
resolution) with 64 kbit/s (8 kHz A-law, ISDN Quality) for each audio channel.
| Format name | Container | Video coding | Bit depth | Color sampling | Frame size | Frame rate and scanning type | Video bit rate, Mbit/s | Audio coding |
|---|---|---|---|---|---|---|---|---|
| DVCAM | MXF, DV-AVI |
DV | 8 | 4:2:0 | 720x576 | 25i, 25p | 25 (CBR) | PCM 4 ch/16 bit/48 kHz |
| 4:1:1 | 720x480 | 29.97i, 29.97p | ||||||
| MPEG IMX | MXF | MPEG-2 422P@ML | 8 | 4:2:2 | 720x576 | 25i, 25p | 30 (CBR), 40 (CBR), 50(CBR) | PCM 8 ch/16 bit/48 kHz, or 4 ch/24 bit/48 kHz |
| 720x480 | 29.97i, 29.97p, 23.98p | |||||||
| MPEG HD | MXF, MP4 |
MPEG-2 MP@H14/HL | 8 | 4:2:0 | 1920x1080 | 29.97i, 25i, 29.97p, 25p, 23.98p | 35 (VBR) | PCM 4 ch/16 bit/48 kHz |
| 1440x1080 | 29.97i, 29.97p, 23.98p (pulldown), 25p | 18 (VBR), 25 (CBR), 35 (VBR) | ||||||
| 1280x720 | 59.94p, 29.97p, 23.98p, 50p, 25p | 25 (CBR), 35 (VBR), 19 (CBR) | ||||||
| MPEG HD422 | MXF | MPEG-2 422P@HL | 8 | 4:2:2 | 1920x1080 | 29.97i, 25i, 29.97p, 25p, 23.98p | 50 (CBR) | PCM 8 ch/16 bit/48 kHz, or 4 ch/24 bit/48 kHz |
| 1280x720 | 59.94p, 50p, 23.98p (pulldown) | |||||||
| Proxy AV | ? | MPEG-4 Part-2 (ASP) | 8 | 4:2:0 | CIF (50i - 352x288) | ? | 1.5 | A-Law 4 ch/8 bit/8 kHz |
1 720p @ 19 Mbit/s is offered by JVC and is equivalent to HDV 720p
Professional Disc (XDCAM and XDCAM HD)
The Professional Disc was chosen by Sony as its medium for professional non-linear video acquisition for a number of reasons, outlined in their white-paper Why Sony Adopted Professional Disc. This disc is similar to Blu-ray Disc
Blu-ray Disc
Blu-ray Disc is an optical disc storage medium designed to supersede the DVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB per layer, with dual layer discs being the norm for feature-length video discs...
and holds either 23 GB of data (PFD23, single-layer, rewritable), 50 GB (PFD50, dual-layer, rewritable) or 128 GB (PFD128QLW, quad-layer, write-once).
Essentially the Professional Disc format was deemed to be a suitable, cost effective and easy step forward. The discs are reliable and robust, suitable for field work (something which has previously been a problem with many disc-based systems). Additionally, the cost of media is comparable to existing professional formats.
SxS
In 2008 Sony introduced a new recording medium to their XDCAM range – SxS Pro . It is a solid-state memory card implemented as an ExpressCard
ExpressCard
ExpressCard is an interface to allow peripheral devices to be connected to a computer, usually a laptop computer. Formerly called NEWCARD, the ExpressCard standard specifies the design of slots built into the computer and of cards which can be inserted into ExpressCard slots. The cards contain...
module. The first camera to use this media was the Sony PMW-EX1 professional video camera
Professional video camera
A professional video camera is a high-end device for creating electronic moving images...
.
In December 2009, Sony introduced the more affordable SxS-1. This unit is designed to have the same performance as the SxS Pro card however its life expectancy is shorter at an estimated 5 years of life when used every day to the card's full capacity.
Memory Stick
Memory Stick cards can be used in Sony XDCAM EX camcorders via the MEAD-SD01 adapter.Secure Digital
Secure Digital memory cards can be used in Sony XDCAM EX camcorders via the MEAD-SD01 adapter.