Genlock is a technology used for synchronizing video equipment so that all devices operate in sync with the same timing. Genlock ensures that various devices, such as cameras, media servers, and video players, are synchronized with a common timing source, preventing issues like image tearing or stuttering.
How Genlock Works
Genlock transmits a clock signal (sync pulse) from one device to another, forcing them to operate at the same frame rate and synchronize their timing. This is particularly important in professional video production, where multiple cameras, video mixers, media servers, and other devices need to be precisely synchronized.
On different devices, you may encounter terms like Reference, Sync Reference, or External Sync.
It is important to know that the reference sync signal is an analog signal and will require an analog distribution amplifier if a larger number of channels is needed.
Genlock Applications
Cameras:
Video Production: In multi-camera systems, such as in television studios or live broadcasts, Genlock is used to ensure that all cameras capture frames simultaneously. This is crucial to avoid delays or tearing when switching between cameras.
Multi-Camera Shooting: When using multiple cameras to capture the same event, Genlock helps synchronize them so that each frame captured by each camera has the same timing.
Media Servers:
Output Synchronization: Media servers using Genlock can synchronize their output video streams with an external sync source, such as a camera or another server. This is critical when using media servers for projection across multiple screens or for real-time video streaming.
Cooperation Between Multiple Servers: When several media servers are used to output video to different screens, Genlock ensures that all servers output images in sync, avoiding mismatches or lags.
Blackburst / Tri-Level Sync
Blackburst and Tri-Level Sync are two different types of sync signals used for synchronizing video equipment in professional video systems.
Blackburst
What It Is: Blackburst, also known as color burst or video sync pulse, is an analog video signal that carries a black frame with synchronization pulses and a color subcarrier. This signal is used to ensure that video devices are synchronized.
Usage: Blackburst is primarily used in SD (Standard Definition, e.g., 480i) systems and sometimes in HD (High Definition) systems. It was the standard for synchronizing analog video equipment and is still used in some legacy systems.
Features: Blackburst provides vertical and horizontal synchronization as well as color synchronization through the color subcarrier signal. This type of signal is simple and effective for basic synchronization in standard definition systems.
Tri-Level Sync
What It Is: Tri-Level Sync is a synchronization signal that uses three voltage levels (positive, zero, and negative) to create a more precise and stable sync signal compared to Blackburst. It provides greater accuracy and reliability in synchronization.
Usage: Tri-Level Sync is used in high-resolution systems like HD (1080p) and 4K, where more precise synchronization is required. It is the standard sync signal for digital video systems and high-resolution equipment.
Features: Tri-Level Sync generates sync pulses at a higher frequency, making it the preferred choice for minimizing jitter and ensuring precise frame alignment in high-resolution video systems.
Genlock Generation
Special devices are used to generate Genlock, creating a synchronization signal that is transmitted to all connected devices.
Popular Devices:
AJA GEN10: A sync generator supporting SD, HD, and 3G-SDI. It can be used to synchronize video equipment, including cameras and media servers.
Blackmagic Design Sync Generator: A simple device for generating Genlock with SDI support. It generates stable clock signals and is used in professional studios for equipment synchronization.
Rosendahl Studiotechnik Nanosyncs HD: A compact and powerful sync generator supporting HD and SD formats. It is used for precise synchronization of video equipment in studio environments.
Optical fiber cable is a cable designed to transmit data through light pulses that travel through thin glass or plastic fibers. The primary advantage of optical fiber cables over copper cables is their high bandwidth capacity and resistance to electromagnetic interference.
Types of Optical Fiber Cables
Single-Mode (SM)
Working Principle: A single laser light beam travels through the center of the fiber.
Core Diameter: Typically around 8-10 microns.
Application: Used for long distances and high-speed data transmission.
Advantages: Lower attenuation and the ability to transmit data over longer distances.
Multi-Mode (MM)
Working Principle: Multiple light beams travel through the fiber at different angles.
Core Diameter: Typically around 50-62.5 microns.
Application: Used for short to medium distances, often in building infrastructures and local area networks (LANs).
Advantages: Cheaper transmitters and receivers.
Bandwidth Capacity
The bandwidth capacity of optical fiber cables depends on several factors, including the type of fiber, transmission technologies used, and distance.
Cable Type
Subtype
Max Distance
Max Data Rate
SM
OS1
Up to 10km
Up to 10 Gbps
SM
OS2
Up to 200km
10 Gbps / Up to 100 Gbps with WDM
MM
OM1
Up to 300m
Up to 1 Gbps
MM
OM2
Up to 550m
Up to 10 Gbps
MM
OM3
Up to 300m
Up to 10 Gbps
MM
OM4
Up to 400m
Up to 10 Gbps
MM
OM5
Up to 150m
Up to 100 Gbps (using WDM)
Types of Connectors
SC (Subscriber Connector)
Connector Type: Push-pull.
Application: Widely used in data transmission and telecommunications networks.
Features: Easy to use and provides reliable connections.
LC (Lucent Connector)
Connector Type: Push-pull.
Application: Commonly used in modern optical networks due to its compact size.
Features: Compact design, suitable for high-density connections.
ST (Straight Tip)
Connector Type: Bayonet.
Application: Frequently used in campus and corporate networks.
Features: Easy to install and remove thanks to the bayonet coupling mechanism.
FC (Ferrule Connector)
Connector Type: Threaded.
Application: Widely used in telecommunications and measurement equipment.
Features: Reliable connections due to threaded coupling.
MTP/MPO (Multi-Fiber Push On/Pull Off)
Connector Type: Push-pull.
Application: Used for connecting multi-mode fibers, often in data centers.
Features: Can connect up to 12 or even 24 fibers simultaneously, allowing for significantly higher connection density.
SRT – a data transmission protocol based on UDP. It is an open-source project developed by Haivision.
SRT Alliance has over 500 members, including Haivision, Sony, Microsoft, Wowza, Panasonic, AVID, AJA, Matrox, BirdDog, Magewell, and Telestream.
Advantages:
Low latency
Original quality
Stream security
Firewall transparency
Route redundancy
Support for any codec
Unlike other protocols, SRT checks for lost packets and retransmits them.
The protocol developers compared SRT and RTMP under real conditions:
In latency tests, SRT was 2.5 to 3.2 times faster (depending on the distance between the sender and receiver).
When using SRT, the maximum speed of 20 Mbps was maintained when transmitting data to any region in the world. With RTMP, the speed decreased with distance. For example, transmission from Europe to Australia showed a speed of no more than 2 Mbps.
Quick Guide to Setting Up SRT
1. Install the Required Software
Ensure you have installed and properly configured software that supports the SRT protocol, such as OBS Studio with the SRT plugin, VLC, or media servers like Wowza Streaming Engine.
2. Determine Connection Parameters
IP Address and Port: Identify the IP address and port that will be used for data transmission. For example, 192.168.1.100:5000.
Mode of Operation: Choose the SRT mode of operation:
Caller: Initiates the connection to another device.
Listener: Waits for an incoming connection from another device.
Rendezvous: Both devices simultaneously initiate a connection to each other.
3. Configure SRT on the Sending Side
Enter the IP address and port of the receiver.
Choose the “Caller” mode.
Configure encryption settings if required (AES 128/256 bit).
Set buffering and latency parameters according to the network quality.
4. Configure SRT on the Receiving Side
Specify the IP address and port where the stream will be received.
Choose the “Listener” mode.
Configure encryption settings to match those on the sending side.
Ensure that the firewall and router are configured to allow traffic through the specified port.
5. Check the Connection
Start streaming on the sending side.
Ensure that the stream is successfully received on the receiving side.
6. Monitoring and Optimization
Use built-in monitoring tools in the software to check the quality of the stream, delays, and packet loss.
Adjust buffering and latency settings as necessary to optimize transmission quality.
Example Configuration in OBS Studio:
On the Sending Side (Caller):
Open OBS Studio.
Go to “Settings” -> “Stream”.
Select “Custom” under the “Service” section.
Enter srt://:?mode=caller (e.g., srt://192.168.1.100:5000?mode=caller).
Configure encryption and buffering parameters if necessary.
Click “OK” and start streaming.
On the Receiving Side (Listener):
Open OBS Studio.
Go to “Settings” -> “Stream”.
Select “Custom” under the “Service” section.
Enter srt://:?mode=listener (e.g., srt://0.0.0.0:5000?mode=listener).
Configure encryption and buffering parameters if necessary.
Click “OK” and start receiving the stream.
This way, you can set up and use SRT for reliable and secure video streaming with low latency.
The most popular electrical connectors are considered to be CEE, Socapex, and Powerlock.
Name
Phases
Amperes
KiloWatts
CEE 16A
1-3
16
Up to 3.7 (single-phase)
11 (three-phase)
CEE 32A
1-3
32
Up to 7.4 (single-phase)
22 (three-phase)
CEE 63A
1-3
63
Up to 14.5 (single-phase)
43 (three-phase)
CEE 125A
1-3
125
Up to 28.8 (single-phase),
86 (three-phase)
Socapex
1
16 (per pin)
Depends on configuration
Powerlock
1-3
Up to 400
Up to 96 (single-phase)
277 (three-phase)
Number of Phases: CEE connectors can be single-phase or three-phase. Socapex connectors are usually single-phase but have many contacts. Powerlock connectors can be either single-phase or three-phase.
Kilowatt Rating: Power (in kilowatts) is calculated based on the standard voltages of 230V (single-phase) and 400V (three-phase). Actual values may vary depending on operating conditions.
Standard: CEE connectors comply with the IEC 60309 standard. Socapex connectors do not have a specific international standard but are widely used in the stage industry. Powerlock connectors comply with the BS EN/IEC 61984 standard.
CEE 16A Plug
CEE 32A Plug
CEE 63A Plug
CEE 125A Plug
SOCAPEX PlugPowerlock PlugsPower Distributor with Powerlock input and Socapex outputs
Useful Formulas
To calculate power in kilowatts (kW) based on the current (in amperes, A) and voltage (in volts, V), the following formulas are used:
If you know the power in kilowatts (kW) and want to calculate the current in amperes (A), you can use the following formulas for single-phase and three-phase systems:
PCIe (Peripheral Component Interconnect Express) is a high-speed interface for connecting components to a motherboard, such as graphics cards, SSDs, and network cards.
Key Features of PCIe:
Speed: PCIe offers high data transfer rates significantly surpassing previous standards (PCI, PCI-X).
Scalability: It uses lanes for data transmission (from x1 to x16), allowing the interface to be adapted for various needs.
Compatibility: PCIe is backward compatible with earlier versions, enabling older devices to work on new motherboards.
Release
Generation
x4
x8
x16
2003
PCIe 1.x
10
20
40
2007
PCIe 2.x
20
40
80
2010
PCIe 3.x
32
64
128
2017
PCIe 4.x
64
128
256
2019
PCIe 5.x
128
256
512
2022
PCIe 6.x
256
512
1024
Bandwidth (Gbit/s)
PCIe-Lanes
PCIe lanes are the fundamental data transmission channels in the PCIe interface. Each lane consists of two pairs of wires, allowing data to be transmitted simultaneously in both directions (input and output), making PCIe a duplex interface.
PCIe lanes play a crucial role in determining the performance and connectivity capabilities of various components in modern computer systems.
CPU
Type
Chipset
CPU Lanes
Chipset Lanes
Coffee Lake Intel 8th/9th
Regular
Z390, H370, B360
16 (PCIe 3.0)
24 (PCIe 3.0)
Comet Lake Intel 10th
Regular
Z490, H470, B460
20 (PCIe 3.0)
24 (PCIe 4.0)
Comet Lake X Intel 10th
Regular
Z490, H470
44 (PCIe 3.0)
24 (PCIe 4.0)
Rocket Lake Intel 11th
Regular
Z590, H570, B560
20 (PCIe 4.0)
24 (PCIe 4.0)
Alder Lake Intel 12th
Regular
Z690, B660
20 (PCIe 4.0)
16 (PCIe 4.0)
Raptor Lake Intel 13th
Regular
Z790, B760
24 (PCIe 5.0)
16 (PCIe 5.0)
Raptor Lake Refresh Intel 14th
Regular
Z890, B860
24 (PCIe 5.0)
16 (PCIe 5.0)
Xeon Scalable (1st Gen)
Server
C620
28 (PCIe 3.0)
6 (PCIe 3.0)
Xeon Scalable (2nd Gen)
Server
C620
48 (PCIe 3.0)
6 (PCIe 3.0)
Xeon Scalable (3rd Gen)
Server
C620
64 (PCIe 3.0)
6 (PCIe 3.0)
Xeon Scalable (4th Gen)
Server
C740
64 (PCIe 4.0)
6 (PCIe 4.0)
Ryzen 3000
Regular
X570, B550
24 (PCIe 4.0)
8 (PCIe 4.0)
Ryzen 5000
Regular
X570, B550
24 (PCIe 4.0)
8 (PCIe 4.0)
Ryzen 7000
Regular
X670, B650
28 (PCIe 5.0)
8 (PCIe 5.0)
EPYC 7001
Server
SP3
128 (PCIe 3.0)
24 (PCIe 3.0)
EPYC 7002
Server
SP3
128 (PCIe 4.0)
24 (PCIe 4.0)
EPYC 7003
Server
SP3
128 (PCIe 4.0)
24 (PCIe 4.0)
For more info about Pcie lines, read my detailed guide to building a media server
LED screens operate on the principle of light modulation. Each pixel consists of three basic LEDs (red, green, and blue), which can be turned on or off and can also adjust brightness. By mixing the light from these LEDs, the screen can create a variety of colors and display images.
There are two types of LED screen cabinets:
Indoor Designed for use indoors, they have high resolution and brightness. Advantages: High image quality and color reproduction, low brightness.
Outdoor Designed for use outdoors, they have enhanced protection against moisture and dust (IP65 standard and above) and high brightness. Advantages: Good visibility in sunlight and resistance to weather conditions.
Brand
Country
NovaStar
China
Linsn
China
Colorlight
China
HollyLite
China
Dicolor
China
Mediacore
China
Xunwei
China
Vanch
China
BrightSign
USA
Barco
Belgium
The most popular manufacturers of LED control systems
Types of Pixel Production Technologies
SMD (Surface-Mounted Device) LEDs are mounted on the surface of the printed circuit board, providing high pixel density and image clarity. Application: Used in various types of LED screens, including indoor and outdoor models.
DIP (Dual In-Line Package) LEDs are housed in plastic packages and placed on the printed circuit board. They are less suitable for high resolutions but are clearly visible from long distances. Application: Commonly used in advertising billboards and outdoor screens.
COB (Chip on Board) LEDs are placed directly on the printed circuit board, improving heat dissipation and brightness. Application: Used in high-quality displays and digital signage.
Mini LED Utilizes smaller LEDs, allowing for increased pixel density and improved image quality. Application: Used in premium LED screens and displays for televisions.
USEFUL FORMULAS
How to determine the pixel pitch of a cabinet:
Width (mm) / Number of pixels 500mm / 200px = 2.5mm Pixel pitch = 2.5mm
How to determine the optimal distance to the screen:
Pixel pitch * 1.5 3mm * 1.5 = 4.5m Optimal distance to the screen = at least 4.5m
EDID (Extended Display Identification Data) is information that allows devices (such as computers, media players, and gaming consoles) to interact with displays (monitors, televisions, and projectors) for optimal adjustment of video and audio output parameters.
Structure of EDID
Manufacturer Identification: Data about the display manufacturer, its model, and serial number.
Supported Resolutions: A list of resolutions that the display supports, including the maximum resolution and refresh rate (for example, 1920×1080 @ 60Hz).
Color Palette: Information about supported colors and color spaces (such as sRGB, Adobe RGB).
Supported Audio Formats: If the display supports audio output, EDID may include information about supported audio formats.
Specifications: Additional information, such as screen size, support for various modes (such as 3D), and other characteristics.
Operating Principle
The signal source (GPU/splitter/controller) makes a request to the display device (monitor/sending card), receives a data table in response, interprets it, and sends a signal corresponding to the data.
Modern graphics cards allow the emulation of arbitrary resolutions, bypassing the EDID data.
Example: In the NVIDIA Control Panel, under the Resolution Changes section –> Create Custom Resolution.
Professional graphics cards in the “Quadro/A” series from Nvidia and “FirePro/AMD Pro” from ATI/AMD have the ability to forcefully embed data at the output from the graphics card, which will not depend on external factors and will be retained even if the display device is turned off.
To emulate or modify EDID, there are both hardware and software solutions available, which can be found among manufacturers like Analog Way, Extron, Kramer, Lightware, as well as from various Chinese noname brands.
An Ethernet cable is a type of cable used for wired connections in local area networks (LAN), such as computers, routers, switches, and other network devices. It transmits data using electrical signals and ensures high-speed and reliable data transmission.
Cat-5
100 Mbps up to 100m
Cat-5e
1 Gbps up to 100m
CAT6
10 Gbps up to 55m
CAT6a
10 Gbps up to 100m
CAT7
10 Gbps up to 100m
CAT8
25 Gbps up to 100m 40 Gbps up to 30m
Cable categories and bandwidth
Ethernet cable types
UTP (Unshielded Twisted Pair): No shielding, minimal interference protection. Used in low-interference environments like offices and homes.
FTP (Foiled Twisted Pair): Overall foil shielding provides medium protection against electromagnetic interference. Suitable for environments with moderate levels of interference.
SFTP (Shielded and Foiled Twisted Pair): Double shielding with foil and braided layers offers high protection against interference. Suitable for high-interference environments.
STP (Shielded Twisted Pair): Each pair of wires has individual shielding, providing high protection against interference. Used in high-interference environments.
ScTP (Screened Twisted Pair): Also known as F/UTP, it has overall foil shielding without individual pair shielding, providing medium protection against interference. Used in moderate-interference environments.
PiMF (Pairs in Metal Foil): Each pair of wires is individually wrapped in foil, offering very high protection against crosstalk and external interference. Suitable for high-performance applications and high-interference environments like data centers and industrial settings.
Cable Type
Full Name
Shielding
UTP
Unshielded Twisted Pair
No shielding
FTP
Foiled Twisted Pair
Overall foil shielding
SFTP
Shielded and Foiled Twisted Pair
Double shielding: foil and braided
STP
Shielded Twisted Pair
Individual shielding for each pair
ScTP
Screened Twisted Pair
Overall foil shielding (F/UTP)
PiMF
Pairs in Metal Foil
Individual foil shielding for each pair
Cable types are arranged from the most unprotected UTP to PiMF – the cable with the highest protection
Cable Crimping
Crimping a cable is the process of attaching an RJ-45 connector to the cable ends to connect network devices. There are two main crimping standards: T568A and T568B, which determine the order of the conductors in the connector.
If you are unsure which standard to use, crimping according to T568B is a safe choice)
Network Device Interface NDI is a standard developed by NewTek for video exchange over a local area network. NDI® allows multiple video systems to find each other and communicate within a LAN, encode, transmit and receive multiple audio and video streams with low latency in real time.