Achieving the expected frame rate - GigE cameras
Several factors may limit the frame rate of a camera:
- Hardware (NIC, GigE cable) capabilities and settings
- Selected 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".
For detailed instructions, see the GigE Installation Manual.
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
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
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