Achieving the expected frame rate - GigE cameras

To achieve the best possible performance of your GigE camera, follow the instructions in the technical manual or user guide for your camera, especially section Configuring the host computer.

Several factors may limit the frame rate of a camera:

  • Hardware (NIC, GigE cable) capabilities and settings
  • Some features such as input trigger speed and mode, pixel format, exposure time, and sensor readout time
  • Working with synchronous image acquisition instead of asynchronous image acquisition

Troubleshooting hardware issues

  • Most often, a defective or insufficient GigE cable is the cause for unexpected bandwidth constraints. We recommend using Category 6 or higher GigE cables. Exchange the cable and check if bandwidth increases.
  • Make sure you are using a 10/100 speed Ethernet NIC. Refer to Hardware Selection for Allied Vision GigE Cameras for recommended NICs.
  • Use a dedicated Ethernet port not shared with internet or local area networks and make sure your antivirus application and firewall do not affect it.
  • Ensure that the NIC settings are correct:
    • Enable “Jumbo Packets”.
    • Set “Interrupt Moderation Rate” to “Extreme”.
    • Maximize “Receive Buffers”.

Troubleshooting camera settings

  • Make sure “Packet Size” is set to “8228”.
  • Check the exposure time. The frame rate cannot exceed 1/Exposure.
  • Make sure DeviceThroughputLimit (legacy term: StreamBytesPerSecond) is set to 124 MB/s.

Bandwidth consumption formula

Estimating the bandwidth consumption or DeviceTroughputLimit (legacy term: StreamBytesPerSecond) value for a specific frame rate:
DeviceThroughputLimit ≈ Height x Width x FrameRate x Bytes per Pixel

Example:
Bandwidth consumption of a Prosilica GT3300 camera that only achieved 1 fps:
3296 x 2472 x 1 x 1 ≈ 8.14 MB/s, multiply by 8 ≈ 65.18 Mb/s
This shows that the camera consumes only 65.18 Mb/s bandwidth.

Assuming camera factory default settings:
Consumed bandwidth of your camera ≈ Height x Width x FrameRate achieved x Bytes per Pixel

Check stream statistics with Vimba:
image
StatFramesDropped > 0 means there’re packets incoming, but all dropping.
Be sure you have jumbo frames enabled on your adapter, see Optimizing Ethernet adapter on page 19. Alternatively, reduce camera packet size value to 1500.