Barco DP2K SLP Series, Руководство пользователя и инструкция по установке

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7. ICMP
7.6 ICMP SDI speci fi cations
3G-SDI
Serial Digital Interface (SDI) is a serial link standardized by ITU-R BT.656 and the Society of Motion Picture and Tele-
vision Engineers (SMPTE). SDI transmits uncompressed digital video over 75-ohm coaxial cable within studios, and
is seen on most professional video infrastructure equipment. The
fi rst revision of the standard, SMPTE 259M, was
de fi ned to carry digital representation of analog video such as NTSC and PAL over a serial interface and is more pop-
ularly known as standard-de fi nition (SD) SDI. The data rate required to transmit SD SDI is 270 Mbps. With the advent
of high-de fi nition (HD) video standards such as 1080i and 720p, the interface was scaled to handle higher data rates
of 1.485 Gbps. The 1.485-Gbps serial interface is commonly called the HD SDI interface and is de fi ned by SMPTE
292M, using the same 75-ohm coaxial cable. Studios and other video production facilities have invested heavily on
the hardware infrastructure for coaxial cable and have a vested interest in extending the life of their infrastructure. For-
tunately, SMPTE recently rati
fi ed a new standard called SMPTE 424M that doubles the SDI data rates to 2.97 Gbps
using the same 75-ohm coaxial cable. This new standard, also called 3-Gbps (3G)-SDI, enables higher resolution of
picture quality required for 1080p and digital cinema.
SDI terminology
Standard HD-SDI signal
Single Link
1.5Gb/s HD 4:2:2
Standard HD-SDI allows for a single 4:2:2 image to be carried on one cable at 1.485 Gb/s. The image uses the Y Cb Cr colorspace
and uses a bit depth of 10 bit per color component.
Due to the data rate limitations only 23.976, 24, 25, 29.970 and 30 fps streams are achievable.
Dual-Link HD-SDI signal
Dual Link
1.5Gb/s
1.5Gb/s
1080p 50/60
1
or
1080p 4:4:4
Dual-Link HD-SDI is mainly two standard HD-SDI signals carrying a single image stream split between the two cables. The main
advantage is that color subsampling is no longer required, and the image can be transmitted in 4:4:4 quality, which then also allows
the RGB (or XYZ) color space to be used.
The main link will contain a standard HD-SDI signal, the second (enhancement) link contains the missing Cb and Cr samples.
Depending on the implementation the enhancement link could also contain extra information to increase the bit depth.
3G HD-SDI signal
3G
3Gb/s
1080p 50/60 (Level A)
or
1080p 4:4:4 (Level B)
3G HD-SDI uses a higher data rate (2.97 Gb/s). This allows a single cable interface to achieve the same capabilities of a Dual-Link
HD-SDI implementation.
In direct mapping (level A) this is used to achieve higher frame rates. (50, 59.940 and 60 fps streams are supported).
1. Not supported in Alchemy
62 R5906847 DP2K SLP SERIES 02/06/2017