MVisionPro Engineering Library · guide
Choosing a camera interface when several pass the bandwidth check
In short
The bandwidth check gives a shortlist, not a decision. Then check four things by part number, in this order: cable run, topology, power and PC hardware. For four 5 MP cameras at 60 fps, the calculator counts three 5GigE channels. That is a lower bound on total capacity, not a wiring plan. Two streams need 4.81 Gbit/s and one channel's budget is 4.50 (calculated), so three channels cannot take four streams. Wire four 5GigE ports with one stream each, or two 10GigE channels with two each.
What the bandwidth check covers
The interface check turns resolution, frame rate, pixel format and camera count into a stream in Gbit/s. It passes every profile, or interface variant, whose useful budget covers it. That budget is the share of the link we count on for image data. Capture boards and slots, processor load, switch capacity, packet loss and drivers are outside the check.
Point-to-point means each camera has its own link to the PC. The calculator uses the figures below.
| Profile | Topology | Useful budget, Gbit/s | Basis | Reference cable |
|---|---|---|---|---|
| FastEthernet, 100BASE-TX | network | 0.09 | our engineering estimate | 100 m |
| GigE, 2.5GigE, 5GigE, 10GigE (BASE-T) | network | 0.90 / 2.25 / 4.50 / 9.00 | IEEE rate (standard), our 90% budget | 100 m, Cat 6A for 10GBASE-T |
| USB3, USB 3.x Gen 1 | point-to-point | 3.60 | 450 MB/s in practice (vendor documentation) | 5 m passive |
| Camera Link Base / Medium / Full / 80-bit | point-to-point | 2.04 / 4.08 / 5.44 / 6.80 | A3 payloads, 255 to 850 MB/s (industry reference) | 10 m copper |
| CoaXPress CXP-6 ×1 / ×2 / ×4 | point-to-point | 5.00 / 10.00 / 20.00 | JIIA rate after 8b/10b coding (standard) | 45 m per line |
| CoaXPress CXP-12 ×1 / ×2 / ×4 | point-to-point | 9.60 / 19.20 / 38.40 | 4.8 GB/s over four links (vendor documentation) | 35 m per line |
Start with the cable run
The machine usually fixes the distance, so read the last column first. A reference length is the cable a profile is based on, not a limit for every cable. CoaXPress length depends on rate and cable type (standard). One JIIA-certified CXP-12 cable series comes in lengths up to 35 m.
So a 30 m run keeps USB3 and Camera Link in play, as a cable check. Find a part number qualified for that profile at that length, active or optical if needed. The rating belongs to that cable, not the interface family.
Decide the topology before you count ports
The calculator returns three counts (calculated).
- Camera connections count one host connection per camera.
- Host channels, on network profiles, divide the total stream by one link's budget and round up. That is total capacity, not a plan of which stream goes where.
- Physical lines count Camera Link links or CoaXPress lanes. On network profiles the field is empty, which does not mean zero cables.
So allocate the streams yourself, one at a time. For this network plan, treat each camera stream as one flow that stays on one channel. Two streams that each need more than half a channel cannot share it, whatever the channels add up to. Link aggregation does not help here: EtherChannel distributes whole flows between links and does not split one flow across them (Cisco documentation).
A switch moves the ports, not the arithmetic. Its per-port mapping, uplinks and backplane must carry the same allocation. Cameras may also plug straight into the PC.
Power on the cable, or a separate supply
Cable power depends on the camera and the far-end equipment, not the interface name.
- USB carries bus power when the camera record says so. MV-CH120-60UC states support for USB 3.0 power supply (datasheet).
- Power over Ethernet (PoE) needs support in both the camera and the switch or injector. Not every GigE camera has it.
- Power over CoaXPress (PoCXP) is specified at 13 W per cable at a nominal 24 V (standard). A camera that draws more can be fed over several cables or from its own supply.
- Power over Camera Link (PoCL) needs a compatible camera, frame grabber and PoCL-rated cable. Otherwise the camera takes power separately.
What the PC has to carry
Camera Link needs a capture card. CoaXPress needs an interface card or frame grabber, the board in the PC that receives the image stream. USB3 and Ethernet need no dedicated board, but the host hardware still needs a plan.
Four USB connections do not mean four USB controllers. Cameras on one controller or hub share it and its link to the PC. Check the controller, the shared link and the PC against the combined stream, then test acquisition. Use separate controllers if the shared resources cannot sustain it. On Ethernet, size adapters, switch ports and uplinks for your allocation, not the total.
Our catalog lists cables for GigE, USB3, CoaXPress and Camera Link apart from frame grabbers.
Worked example: four 5 MP cameras at 60 fps
Assume four cameras 3 m from the PC, each sending a full 2448 × 2048 frame at 60 fps. The format is Mono8: monochrome, eight bits per pixel on the wire.
One camera makes 2.41 Gbit/s (calculated). Twelve of sixteen profiles pass the bandwidth check. FastEthernet, GigE, 2.5GigE and Camera Link Base do not. Four cameras make 9.63 Gbit/s (calculated). The same twelve pass, and three counts from our tools API (application programming interface) tell them apart.
| Profile | Camera connections | Host channels | Physical lines |
|---|---|---|---|
| USB3 | 4 | 4 | 4 |
| 5GigE | 4 | 3, capacity lower bound | not computed |
| 10GigE | 4 | 2 | not computed |
| Camera Link Medium, Full, 80-bit | 4 | 4 | 8 |
| CoaXPress CXP-6 ×1, CXP-12 ×1 | 4 | 4 | 4 |
| CoaXPress ×2 and ×4 variants | 4 | 4 | 8 and 16 |
The calculator page shows one recommendation and an expandable comparison, both in camera connections only. Here it reads "4 5GigE network ports required".
On 5GigE, three is just 9.63 divided by 4.50, rounded up. Two streams make 4.81 Gbit/s (calculated), more than one channel's 4.50. So wire four 5GigE ports, one stream each. On 10GigE, a pair at 4.81 Gbit/s fits one channel's 9.00. Two channels work if the switch, its uplink and its backplane are sized for those pairs.
On USB, one Gen 1 connection budgets 3.60 Gbit/s, so two of these streams cannot share a connection or uplink.
The physical lines complete the parts list: eight links on capture cards for Camera Link Medium, four coaxial lines into a frame grabber for CXP-12 ×1, adapters and ports for Ethernet.
Calculate for your case
The link carries the whole requirement. Open the one-camera case or the four-camera case and type your own values over it.
The link does not pick an interface, and the page has no manual profile selector. Only the API filters to one profile, through the interface parameter of the interface endpoint under /tools/api/v1/, which the link leaves out.
The page opens in manual mode. Picking a catalog camera in its model search switches to that camera's full frame, maximum frame rate, interface and pixel format.
Equipment: two candidates and one near miss
Two records pair 5 MP-class geometry with a top frame rate above 60 fps (datasheet). MV-CH050-90XM-C-NN has 2592 × 2160 pixels at up to 213 fps in Mono8, on CoaXPress with a DIN interface. MV-CH050-10CM has 2432 × 2048 pixels at up to 140 fps, on Camera Link SDR.
The Camera Link record lists Base, Medium, Full and 80-bit configuration modes in a separate field. That field does not combine freely with the top frame rate. At 140 fps and eight wire bits, the frame makes 5.58 Gbit/s (calculated), which only 80-bit at 6.80 Gbit/s carries. At 60 fps it makes 2.39 Gbit/s (calculated), already above Base's 2.04 Gbit/s. That is bandwidth arithmetic, not a mode the datasheet confirms.
Neither camera has exactly the example's 2448 × 2048 frame. Confirm mode, pixel format and frame size on the exact variant, plus connector, cable, power and host board.
MV-CS050-10GM is the near miss: exactly the 2448 × 2048 frame on Gigabit Ethernet, but a confirmed maximum of 24.2 fps (datasheet). All these figures are full frames at the confirmed maximum. They are not region-of-interest limits and do not cover every pixel format.
Common mistakes
- The shortlist is taken as the decision, and a 20 m USB run gets a passive cable that does not reach. Enter the run length and qualify a cable for it.
- Three 5GigE host channels are bought as three ports, and two streams land on a port that cannot hold them. Allocate streams one at a time, then order.
- Power is read off the interface name: assumed on an Ethernet camera, ruled out on Camera Link where PoCL-rated parts would carry it. Confirm camera, board and cable part numbers before routing cables.
- "No frame grabber needed" becomes "no host hardware needed", and four cameras share one USB controller. Compare what each shared resource carries with its documented total.
When this rule breaks
Passing the check proves only that the image data fits the profile's budget. It does not prove zero dropped frames, enough host processing, storage throughput or steady latency. Nor does it clear the transport as a cause.
If a link that passed still loses frames, check the whole chain during commissioning (vendor documentation). Read the counters for incomplete and skipped images, lost packets, free buffers and underruns. Check the driver and how long the application takes per image. On a network, check the adapter's packet size, the camera's transmission delays, the switch and its uplinks. Include the PCI Express and storage path.
A profile is also not a camera. The model's record says which transports it has, in which pixel format and at what frame rate.
Next step
Send us the resolution, frame rate, pixel format and camera count. Add each camera's distance to the host and whether it takes power from the cable. We will allocate the streams to ports and channels against the current profiles. We will also say where you need a frame grabber, another adapter or a separate power supply.
Sources
- MVisionPro engineering calculator: interface profiles, useful image budgets, reference cable lengths and the multi-camera connection counts; core public-calc-core-v1, reproduced against the frozen data snapshot on 2026-09-21
- Hikrobot catalog records (datasheet fields: resolution, maximum frame rate, data interface, configuration mode, power supply), catalog snapshot of 2026-09-18
- IEEE 802.3ab, IEEE 802.3bz and IEEE 802.3an family rates with our conservative 90% image budget — the basis of the Ethernet profiles, their 100 m reference length and the Cat 6A basis of 10GBASE-T
- A3 Camera Link standard page — payloads of 255 / 510 / 680 / 850 MB/s and Power over Camera Link; checked 2026-09-21: https://www.automate.org/vision/vision-standards/vision-standards-camera-link
- Euresys documentation on Power over Camera Link — SafePower detection and one- or two-cable PoCL configurations; checked 2026-09-21: https://documentation.euresys.com/Products/eGrabber/eGrabber_25_02/20/en-us/Content/03_Interfaces/functional-guide/cl/power-over-camera-link.htm
- Teledyne application note on a USB 3.1 multiple-camera setup — the practical USB maximum of about 450 MB/s and the resources shared by cameras on one host controller; checked 2026-09-21: https://www.teledynevisionsolutions.com/support/support-center/application-note/iis/usb-3.1-multiple-camera-setup
- Teledyne DALSA Xtium2 announcement — 4.8 GB/s sustained acquisition across four CXP-12 links, the basis of the CXP-12 useful figure; checked 2026-09-21: https://www.teledynedalsa.com/en/news/newsroom/teledyne-dalsa-expands-its-xtium2-frame-grabber-series-with-three-new-coaxpress-models/
- JIIA CoaXPress standard CXP-001-2021 v2.1 — lane rates, rate- and cable-dependent length, and PoCXP at 13 W per cable at nominal 24 V; checked 2026-09-21: https://jiia.org/wp/wp-content/themes/jiia/pdf/standard_dl/coaxpress/CXP-001-2021.pdf
- JIIA certified cable record for a CXP-12 fixed-cable series listed in lengths up to 35 m; checked 2026-09-21: https://jiia.org/en/cxp_old/canare_cxp-12-fixedcable_series/
- Edmund Optics, camera types and interfaces for machine vision applications — capture-board need, power architecture and the warning that Power over Ethernet is not on every GigE camera; checked 2026-09-21: https://www.edmundoptics.com/knowledge-center/application-notes/imaging/camera-types-and-interfaces-for-machine-vision-applications
- Basler CoaXPress hardware installation — interface card or frame grabber requirement and PoCXP versus separate camera power; checked 2026-09-21: https://docs.baslerweb.com/hardware-installation-%28coaxpress-cameras%29
- Basler stream-grabber parameters, lost-packet troubleshooting and buffer handling — the counters and settings to check when a link that passes the budget loses frames; checked 2026-09-21: https://docs.baslerweb.com/stream-grabber-parameters
- Basler Bandwidth Manager — bandwidth shared by cameras on the same host resources; checked 2026-09-21: https://docs.baslerweb.com/bandwidth-manager
- Cisco EtherChannel load balancing — why aggregated links distribute whole flows instead of splitting one stream; checked 2026-09-21: https://www.cisco.com/c/en/us/support/docs/lan-switching/etherchannel/12023-4.html
Related
How this material was prepared
Prepared by MVisionPro from the stated sources and the MVisionPro calculation engine. A physical test is claimed only when the material says so explicitly. Read the editorial method.
Editorial status: verified. Content updated 2026-09-23.