CoaXPress is an asymmetric, high-speed point-to-point serial communication standard for the transmission of uncompressed video and still images. The standard is hosted by the Japan Industrial Imaging Association (JIIA). The current version (2.1) was released in February 2021 and we are awaiting the finalisation and release of version 3.0 later this year.
The History of CoaXPress
The first public demonstration of CoaXPress took place at VISION 2008 in Stuttgart. It subsequently became an international machine vision interface standard in 2011, after years of development by a consortium of companies, including Active Silicon.
The technology won the prestigious Vision Award for technical innovation in 2009 and CoaXPress has since become well-established for high-bandwidth applications in the ever-growing imaging market. The standard is continuously adapted to meet the latest requirements of the vision market.
Key Capabilities of CoaXPress
CoaXPress delivers very high data throughput and robust, scalable system design:
- High-speed data rates: up to 12.5 Gbps per connection (single coax cable).
- Speed is scalable: Multiple cables aggregated for higher bandwidth (e.g. 4 cables give 50 Gbps etc).
- Bidirectional channels: a high-speed downlink for image data and a 42 Mbps uplink channel for camera control, triggering and firmware updates.
- Power over CoaXPress: up to 13W per cable.
- Long reach: Cable lengths up to 35m at CXP-12 and 100m at CXP-3 using Belden 1694 cable. Optical fiber supports transmission over many kilometers.
- Full GenICam support, including GenTL, simplifies software integration and interoperability between components, providing an easy “out-of-the-box” user experience.
- GenDC (Generic Data Container), to support the transmission of complex data such as 3D images. (learn more)
- Precise triggering capability and real-time data transfer with virtually no latency.
- Flexible and rugged cabling: standard 75 Ohm coax cable with industrial reliability and cost-efficiency.
- CoaXPress over Fiber (an extension to v2.1) allows the CoaXPress protocol to be used with fiber optic links.
- Hot pluggable: Devices can be connected or disconnected without powering down the system.
- Royalty-free: No licensing fees apply to the standard itself.
Why CoaXPress Matters in Machine Vision
The high speeds and low latencies combined with the simplicity, scalability, and robustness of the cabling are clear benefits to CoaXPress. These capabilities are critical in industrial inspection, metrology and automated production environments where the adoption of CoaXPress has led to faster image processing of more data using higher resolution cameras, and ultimately, more efficient production lines.
CoaXPress is the go-to interface option where applications have been limited by the slower speeds and short cable lengths of Camera Link or USB3 Vision, and the slower speeds and high CPU loading costs of 10 GigE Vision.
In particular, the adoption of CoaXPress in the inspection and metrology sectors has led to faster image processing of more data using higher resolution cameras, and ultimately, more efficient production lines.
Because CoaXPress is an international machine vision standard, a wide choice of compatible cameras and frame grabbers is available. This gives engineers flexibility to tailor systems to specific throughput, resolution and processing needs.
CoaXPress v3.0
The use of CoaXPress is an investment in the future because the development of the standard leads the way to even faster image data acquisition and transfer. The technical committee is working on the latest version of CoaXPress, version 3.0, which is expected to be finalised and released later in 2026.
The key feature of the new release will be the introduction of speeds up to 25 Gbps/connection, for use with coax copper cables and optical fiber links.
Fiber optic technology (CoaXPress over Fiber) will be fully integrated into the standard (an add-on since v2.1). Faster triggering rate over coax and support for forward error correction will also be available.
Resources on CoaXPress
If you are new to working with CoaXPress or are selecting components for a vision system, have a look at our guide for engineers:
For further details on machine vision standards, please visit our machine vision standards webpage.
Further resources
- CoaXPress (JIIA)
- Wikipedia on CoaXPress
- Guide to Understanding Machine Vision Interface Standards Brochure (PDF for download)
- Active Silicon’s update on CXP v3.0
- Active Silicon’s update on the new CXP 2.1 release
- Chris Beynon explains CoaXPress v2.0
Active Silicon‘s Role in CoaXPress
Active Silicon has been involved with the CoaXPress standard since its early development and introduced the industry’s first CoaXPress frame grabbers to the market in 2011.
We continue to participate in the standards work, and our CTO, Chris Beynon, chairs the CoaXPress Technical Committee and was one of the original authors of the specification.
Visit our frame grabber products page to see our range of FireBird CoaXPress cards, which include:
- Quad CXP-12 frame grabbers
- 8-connection CXP-12 card designed for multi-camera systems
- CoaXPress over Fiber frame grabber
- Cost-optimized 1xCXP12 and 2x-CXP-12 cards
