Article
Recording several cameras at once and managing them in one ALTRON window
One camera views the surface of the sheet from above and another views its edge. Or, in a lab, a color camera and a monochrome camera capture images of the same sample simultaneously. The first question is usually: should we open a separate instance of the software for each camera? In ALTRON you don't need to. All cameras are in one window and simultaneous recording from multiple cameras takes a single command.
After you press Get, ALTRON builds a separate chain for each detected camera:
- Each camera model has its own graph. A color line-scan camera works with one graph and a monochrome area-scan camera with another.
- Cameras whose serial numbers share the same first four characters form a family. If you change the graph for one of them, the rest of the family also opens the same graph.
- Each camera's settings are saved in a separate file named after that camera's serial number. If you swap the cables, the settings do not get mixed up.
- A camera connected for the first time starts from the most recent settings of its family, so you don't start from scratch.
In the middle section, each camera has a panel. The viewers of that camera's graph are in this panel. The panel title shows the camera's serial number and description.
- Click a camera's panel to make that camera active. Its title turns a lighter color. From then on, the settings column and the diagnostics panel belong to that camera.
- Double-click a panel's title to show only that camera. Double-click again and all of them come back.
- Ui Search results are shown with a camera prefix, so you know which camera's setting you have found.
A common mistake: people change the exposure and then find that the other camera's image has changed. Before any change, look at the colored panel title.
If you press Start on the recorders of two cameras one after the other, you get two files that started at two different moments. Instead, use the Tools menu, Record submenu:
Each camera panel also has its own record button. When you need only one camera, use that.
Begin Record All starts the recordings together from the software. If the frames from two cameras must be captured at exactly the same instant, drive the cameras with a shared hardware trigger signal.
Set Common Params gives all of them one path, but it does not keep the file names apart. We recommend this order:
- In each camera's recorder, set a name that identifies the camera, such as top_ and edge_. Enter this name in the Prefix field. In the raw-data recorder this field is called File Name.
- Press Set Common Params for the path and the limits.
- Make a short test recording with Begin Record All and check the file names.
We cover the name format and automatic folder structure in detail in the article on file naming.
All cameras share one processor, one memory and one disk. Below the camera list you can see CPU and RAM usage, both for the whole system and for ALTRON itself. If the CPU is close to 100 percent, frames are lost. With several high-speed cameras, also keep an eye on each recorder's cache bar. The disk now has to write everyone's data at the same time.
To learn more about machine vision, Wikipedia article (English).
To choose the right combination of cameras, see the camera comparison page. If you're designing a multi-camera station and are unsure about computer capacity or recording synchronisation, send us the details through contact page.