In high-performance imaging systems, selecting an appropriate camera interface is a critical decision that influences performance, reliability, and convenience. Two popular interfaces—GMSL (Gigabit Multimedia Serial Link) and GigE (Gigabit Ethernet)—offer distinct benefits. Selecting between GMSL and GigE interfaces depends on the application’s requirements.
For instance, GMSL excels in scenarios demanding high-speed data transfer while in contrast, GigE offers extended cost savings. In this blog, you’ll get insights on all the differences between these two camera interfaces and what makes each a unique answer to what a million-dollar question could be – “Does my application need the GMSL or GigE interface?”
Understanding the GMSL Camera Interface
The GMSL camera interface is engineered for high-speed data transmission. It uses Serializer/Deserializer (SerDes) technology to convert and transport data between different components. The serializer and deserializer components are at the heart of this interface.
The serializer is responsible for converting parallel data into a high-speed serial stream, which is then transmitted over a single coaxial cable. This cable supports high-speed data transmission and enables bidirectional communication. The deserializer, on the receiving end, converts the serial data back into parallel form for further processing.
One of the benefits of GMSL cameras is their ability to maintain data integrity even at high transmission speeds. The use of a single coaxial cable simplifies the physical setup while enabling the transfer of high-resolution video signals. The GMSL interface design also empowers the camera to handle a variety of video output standards, including HDMI, CSI-2, DSI, and more.
Understanding the GigE Camera Interface
GigE, short for Gigabit Ethernet, is another widely used camera interface. GigE cameras connect to a network using an Ethernet cable, typically classified as either Unshielded Twisted Pair (UTP) or Shielded Twisted Pair (STP). The STP variant, equipped with shielding, is useful in environments with high Electromagnetic Interference (EMI), ensuring data transmission remains stable.
GigE cameras are built with an onboard processing chip that compresses images or video as they are captured. This compression helps minimize the bandwidth required for transmission so
that the camera can send data over long distances without overwhelming the network. The Ethernet cable itself is capable of spanning up to 100m without signal loss.
Moreover, GigE cameras adhere to the ONVIF standard, which drives interoperability between devices from different manufacturers. This standardization is crucial in scenarios where multiple cameras and network video recorders must work together seamlessly.
Comparison between GMSL and GigE Camera Interfaces
Distance of transmission
GMSL: GMSL cameras are well-suited for applications requiring short—to medium-distance transmission. They enable the camera to be positioned up to 15m away from the host processor while maintaining high-speed operation, a high frame rate, and minimal latency.
Hence, GMSL is a strong interface for drones and autonomous vehicles, where high-speed data transmission within a confined space is crucial.
GigE: GigE cameras shine in cases where longer transmission distances are required. The interface supports cable lengths of up to 100m without needing repeaters or extenders. For even longer distances, Ethernet extenders can stretch the reach to 200m, providing both data and power transmission.
In certain setups, with some trade-offs, cascading extenders can extend the range up to 500m, making GigE ideal for industrial automation and surveillance applications.
Data transfer speed
GMSL: GMSL cameras deliver great image quality and bandwidth at distances up to 15m. They are perfect for real-time data processing and low latency, empowering large drones, agricultural machinery, and logistics robots. These applications benefit from the GMSL interface’s ability to handle high data throughput for smooth operations in demanding environments.
GigE: Although GigE can manage high data rates, it is generally leveraged by applications where speed is important but not as critical. GigE cameras are used in less demanding setups where longer cable lengths outweigh the need for ultra-high-speed data transfer, offering a balance between performance and practicality.
EMI/EMC performance
GMSL: EMI is a major concern in high-speed data transmission, as it can degrade the performance of electronic systems. GMSL addresses this issue with an integrated programmable output spread spectrum capability. It helps reduce interference without the need for an external spread-spectrum clock.
Also, the high-immunity mode in the GMSL serializer provides control channel EMC tolerance.
GigE: GigE cameras meet the basic EMI/EMC standards required for embedded vision applications. However, they may not offer the same level of EMI protection as GMSL, which can be a consideration for applications where EMI could pose a problem.
Cost implications
GMSL: The cost of a GMSL setup can be influenced by the need for separate power and video cables, which increases labor time and installation complexity. However, with the introduction of GMSL2 and its PoC capability, all data, control signals, and power can be transmitted through a single coaxial cable. It reduces the overall costs, making it a more flexible option.
GigE: GigE cameras are generally more cost-effective, especially for new installations. They require less cabling, reducing both material costs and installation time. Moreover, using PoE extenders for longer distances further reduces costs, making GigE a better choice for budget-conscious projects that require extended transmission distances.
GMSL and GigE Cameras Offered by e-con Systems
e-con Systems has over 20 years of experience in designing, developing, and manufacturing OEM camera solutions.
e-con systems™ GMSL cameras use GMSL, GMSL2 & GMSL3 technology. These cameras can operate at full speed with minimal latency and high frame rates, even when positioned up to 15 meters from the host processor via a coaxial cable.
Our GigE cameras come with integrated ISPs, offering advanced imaging controls. These cameras support networked multi-camera setups with synchronization through PTP. The Ethernet interface leverages existing infrastructure, enabling straightforward integration and cost-effective development.
e-con Systems also provides customizable options, covering sensor selection, form factor, optics, etc.
Explore our Camera Selector to get a complete view of our full portfolio.
If you need any help integrating the right GigE or GMSL camera into your application, please write to camerasolutions@e-consystems.com.
Prabu is the Chief Technology Officer and Head of Camera Products at e-con Systems, and comes with a rich experience of more than 15 years in the embedded vision space. He brings to the table a deep knowledge in USB cameras, embedded vision cameras, vision algorithms and FPGAs. He has built 50+ camera solutions spanning various domains such as medical, industrial, agriculture, retail, biometrics, and more. He also comes with expertise in device driver development and BSP development. Currently, Prabu’s focus is to build smart camera solutions that power new age AI based applications.