Using the capture device
- In the host application, select the video capture device
Datastead GenICam Vision Source. - Open its property pages to pick the GenTL producer and the camera, and to set the pixel format, ROI and acquisition parameters.
- Run the graph (preview / capture).
Before / during streaming
The producer, the device, the pixel format, the ROI and the binning must be set before the graph runs; they are fixed for the session once streaming starts. Stop the graph to change them. Exposure, gain, frame rate and white balance can be changed on the fly.
Property pages
The filter implements ISpecifyPropertyPages: any host that shows the filter property frames (GraphStudioNext, the TVideoGrabber ShowDialog, the "properties" button of most capture applications) gets six tabs.
| Page | Settings |
|---|---|
| Device | GenTL producer (.cti) selection with Browse... and Refresh, camera selection, device information, and a Reset to defaults button |
| Image | pixel format (Auto / Mono8 / BGR8 / BayerRG8 / YCbCr422_8), ROI (offset and size, plus Full frame), horizontal and vertical binning |
| Exposure | exposure time and auto, gain and auto, frame rate and its enable (the camera-reported maximum is shown next to the value), auto white balance |
| Trigger | free-run, software or hardware trigger, plus a software Fire button |
| Features | generic GenICam (SFNC) access: type a feature name, choose its type, then Get / Set / Run. Reaches every setting the camera exposes |
| About | product and version, and the license state ("Licensed to |
Pixel formats
| Choice | Delivered to the graph | Notes |
|---|---|---|
| Auto | the best format the camera supports | default |
| Mono8 | MEDIASUBTYPE_Y800 (8-bit grey) |
|
| BGR8 | MEDIASUBTYPE_RGB24 |
debayered on board by the camera |
| BayerRG8 | MEDIASUBTYPE_RGGB (raw Bayer) |
debayered by the host; limited to 60 s in the evaluation version |
| YCbCr422_8 | MEDIASUBTYPE_UYVY |
Settings persistence
The page settings (pixel format, ROI, binning, exposure and auto, gain and auto, frame rate and enable, white balance, brightness, contrast, trigger mode) are stored per camera entry under HKCU\Software\Datastead\DtstdGenicam\Cam<N> and re-applied automatically when the camera opens. A value entered in the dialog therefore survives closing and reopening it, including when the host opens the property frame on a separate, short-lived filter instance (a common DirectShow pattern): the capture instance reloads the same persisted values.
The selected producer and device are persisted separately (see GenTL producer (.cti)). The Reset to defaults button of the Device page clears the persisted page settings without touching them.
Standard DirectShow controls
The filter implements the standard IAMCameraControl and IAMVideoProcAmp interfaces, so the usual "camera control" and "video quality" dialogs of the host work directly. Each control is mapped to the matching camera feature and is only offered when the camera actually supports it:
| Control | Interface | Camera feature (SFNC) |
|---|---|---|
| Exposure, with auto | IAMCameraControl |
ExposureTime / ExposureAuto |
| Gain, with auto | IAMVideoProcAmp |
Gain / GainAuto |
| White balance (auto) | IAMVideoProcAmp |
BalanceWhiteAuto |
| Gamma, Hue, Saturation, Sharpness | IAMVideoProcAmp |
Gamma, Hue, Saturation, Sharpness, when the camera exposes them |
| Brightness | IAMVideoProcAmp |
IntensityControllerTarget (auto-exposure / auto-gain target, see below) |
| Contrast | IAMVideoProcAmp |
ContrastEnable / ContrastDarkLimit / ContrastBrightLimit (tone stretch), when the camera provides them |
Frame rate: the acquisition frame rate limit is enabled and set from the Exposure page (or SetAcquisitionFrameRate).
Brightness on Allied Vision Alvium cameras
On Alvium cameras, Brightness drives the auto-exposure / auto-gain target (IntensityControllerTarget, in percent). It has an effect only while Exposure auto or Gain auto is enabled: with both in manual mode, the slider changes nothing. Enable auto on Exposure (camera control) or Gain (video quality) first, then adjust Brightness to make the automatic control aim for a brighter or darker picture.
The available controls and their ranges are read from the camera itself, so they vary by model. A control the camera does not expose (or exposes as read-only) appears unavailable in the host dialog; the Features page shows the exact camera capabilities.
Triggering
Three modes, from the Trigger page or SetTriggerMode:
| Mode | Behaviour |
|---|---|
| Free run (0) | the camera streams continuously at its frame rate |
| Software trigger (1) | one frame per Fire button / SoftwareTrigger() call |
| Hardware trigger (2) | one frame per pulse on the camera's external input line (TriggerSource = the first hardware line the camera enumerates, Line0 on Allied Vision cameras) |
Acquisition statistics
IGenicamControl::GetStats returns the delivered, dropped, incomplete and erroneous frame counters, the last frame id and the current frame rate, for host-side monitoring. See the Interface reference.