CoaXPress combines the best features of other interfaces into just one future proof hi-speed vision interface solution.
Camera Link disadvantages:
- Short, stiff, thick & expensive cables
- Connectors not field installable
- Speed limited to Camera Link Full – 6 Gb/s
- Power over Camera Link: limited power available, not supported by all cameras and frame grabbers
- Speedwise a step back compared with CameraLink (comparable with CL Base)
- Available power over USB is low: 4.5W
- Cable length is limited to 3m, perhaps 5m – no slip ring use possible
- Relies on CPU – load increases with speed
- QoS questionable (certainly at highest speed)
- No offloading of processing & buffering to frame grabber FPGA and memory
- Only useful for low end applications – will mainly compete with IEEE-1394B (and GigE Vision 1Gb/s for short distances)
- And for all: many conductors used, so slip rings are expensive!
HS-SDI / 3G-SDI / HDCCTV disadvantages:
- Limited available bandwidth – not scalable
- Optimized for TV standards only (480p, 575p, 1080i, 1080p etc)
- Supports only continuous video (no asynchronous operation)
- Scrambling is less robust than 8b/10b coding
- No uplink to camera for communication & trigger (5 Mb/s foreseen for HDCCTV)
- No power for camera (only foreseen in HDCCTV)
10 Gig e disadvantages:
- Power hungry: Relies on CPU and internal PC memory bus
- Standard not very efficient with lots of data, more efficient due to own protocol (GigE has a much used interface with an own dedicated protocol with high reuse of hardware, protocol, standard and software at the PC.)
- PnP discovery and operation under all circumstances needed: complex.
- Network interface: You can not offload processing & buffering to frame grabber FPGA and memory
- A network frame grabber is needed for direct vision processing / analysis and for more efficient image data transfer.
- Bottleneck when using multiple cables: Image first has to be combined at a single point at the PC-side before further processing at 1 or more PC’s.
- The single point PC has to do the work at a very high speed.
- 10 GigE PHY’s and MAC’s are only used in server applications – lacks the benefit of commercial market pull
- Cat-6/Cat-7 cables are inferior compared to coaxial cables (maximum speed, attenuation, flexibility, reliability, use with slip rings)
- Power over cable, real time trigger possibilities are only planned in version 2.0 of GigE Vision
- Applications using 10 GigE will need a frame grabber to offload CPU and memory of PC – an important benefit of GigE Vision is then gone.
Benefits of CXP over HSLink:
- Coaxial cables
- Long length (even at higher speed) – Optical can run longer distance
- Many cable options already available
- High flex / high reliability (impossible with CX4)
- Rugged / High temperature
- Aerospace, Clean room compatible, …
- Upgrade path for legacy systems
- Low cost
- Silicon designed for the specification (rather than specification written around available silicon)
- Consortium member input into standard