FAQ

This page collects short answers to questions that come up often when using genicam-rs or bringing up a new camera.

If you are stuck, also check:

• Discovery
• Streaming
• Networking

and the issues in the GitHub repository.

“Discovery finds no cameras. What do I check first?”

Run:

cargo run -p gencamctl -- list

If it shows nothing:

1. Physical link
   • Are the link LEDs lit on camera, NIC, and switch?
   • Try a different cable or port.
2. IP addresses
   • Host NIC and camera must be on the same subnet (e.g. 192.168.0.x/24).
   • Avoid having two NICs on the same subnet; routing will get confused.
3. Firewall
   • Allow UDP broadcast/unicast on the NIC used for cameras.
   • On Windows, make sure the binary is allowed on the relevant network profile (Private / Domain).
4. Multiple NICs
   • Use --iface to force the interface:

cargo run -p gencamctl -- list --iface 192.168.0.5

See also: Discovery tutorial and Networking.

⸻

“The vendor viewer works but genicam-rs doesn’t. Why?”

Common causes:

• Different NIC / interface:
  • The vendor tool may be using a different NIC or IP selection strategy.
  • Compare which local IP it uses and pass that as --iface to gencamctl.
• Different stream destination:
  • The camera might be configured to stream to a specific IP/port.
  • Ensure genicam-rs uses the same host IP and port, or reset the camera configuration to defaults.
• Different MTU / packet size / packet delay:
  • Vendor tools sometimes auto-tune these.
  • Try matching their settings using GenApi features (packet size, frame rate, inter-packet delay).

When in doubt:

• Capture logs with RUST_LOG=debug and compare behaviour at the same frame rate and resolution.

See: Streamingand Networking.

⸻

“Does this work on Windows?”

Yes. Windows is a first-class target alongside Linux and macOS.

Notes:

• Make sure the firewall allows discovery and streaming:
  • When Windows asks whether to allow the executable on Private/Public networks, allow it on the profile you use for the camera network.
• Configure the NIC for the camera network with a static IPv4 address, separate from your office/internet NIC.
• For high-throughput setups:
  • Consider enabling jumbo frames on the camera NIC.
  • Disable power-saving features that can introduce latency.

See: Networking for NIC configuration details.

⸻

“How do I set exposure, gain, pixel format, etc.?”

Use the GenApi features via gencamctl or the genicam crate.

Examples with gencamctl:

# Read ExposureTime
cargo run -p gencamctl -- \
  get --ip 192.168.0.10 --name ExposureTime

# Set ExposureTime to 5000 (units depend on camera, often microseconds)
cargo run -p gencamctl -- \
  set --ip 192.168.0.10 --name ExposureTime --value 5000

# Set PixelFormat by name
cargo run -p gencamctl -- \
  set --ip 192.168.0.10 --name PixelFormat --value Mono8

For more, see: Registers & features.

⸻

“What are selectors and why do my changes seem to disappear?”

Many cameras use selectors to multiplex multiple logical settings onto one feature. Example:

• GainSelector = All, Red, Green, Blue, …
• Gain = value for the currently selected channel.

If you set Gain without first setting GainSelector, you might be modifying a different “row” than you expect.

Typical sequence:

cargo run -p gencamctl -- \
  set --ip 192.168.0.10 --name GainSelector --value Red

cargo run -p gencamctl -- \
  set --ip 192.168.0.10 --name Gain --value 5.0

See: Registers & features and the selectors_demo example in the genicam crate.

⸻

“Do I need to care about the GenApi XML?”

For most applications, no:

• You can use features by name and let genapi-core handle the mapping.

You should look at the XML when:

• A feature behaves differently from the SFNC / vendor documentation.
• You are debugging selector or SwissKnife behaviour.
• You are contributing to genapi-core or genapi-xml.

See: GenApi XML tutorialand the crate chapters for genapi-xml and genapi-core when they are filled in.

⸻

“How do I save frames and look at them?”

With gencamctl:

• Use stream with an option like --count / --output (exact flags depend on the CLI):

cargo run -p gencamctl -- \
  stream --ip 192.168.0.10 --iface 192.168.0.5 \
  --count 100 --output ./frames

This typically saves a sequence of frames in a simple format (e.g. raw, PGM/PPM) that you can inspect with:

• Image viewers.
• Python + NumPy + OpenCV.
• Your own Rust tools.

See: Streaming.

⸻

“How do I generate documentation?”

• mdBook (this book):
  • From the repository root:

cargo install mdbook  # if not already installed
mdbook build book

- The rendered HTML will be under book/book/.

• Rust API docs:
  • From the repository root:

#![allow(unused)]
fn main() {
cargo doc --workspace --all-features
}

- The rendered HTML will be under target/doc/.

Many users publish these via GitHub Pages or another static host; see the repository CI configuration for details.

⸻

“Where should I report bugs or ask questions?”

• For bugs or feature requests, open an issue in the GitHub repository with:
  • A clear description of the problem.
  • Your OS, Rust version, and camera model.
  • A minimal reproduction if possible (CLI commands or small Rust snippet).
  • Relevant logs (e.g. RUST_LOG=debug output).
• For questions that may be general (not specific to this project), link to:
  • The camera’s data sheet or GenICam XML snippet if relevant.
  • Any vendor tools you used to compare behaviour.

Good issues make it much easier to improve the crates for everyone.