The IIDC 1394-based Digital Camera Specification (Version 1.31) requires that the camera hardware retain a record of all the features the camera supports. Software and drivers used to control the camera can query the camera to get a list of supported features and other information. The IIDC specification allows for the definition of advanced features - known as extensions - that are camera specific.
The following defines the current list of PixeLINK Extensions.
Camera information retrieval: This feature reports the camera’s hardware and firmware information, specifically the firmware version, the FPGA version, the camera’s serial number, and the product ID.
Camera Name: This feature allows the name of the camera to be read and set. It is a text string of up to 256 characters in length.
GPIOs: The IIDC specification does not have enough control of strobes, flashes, or LEDs. A PixeLINK extension allows control of multiple strobes and a general purpose I/O. The extension also allows control of the time between a trigger event and the activation of a strobe, the duration of the strobe and the polarity of the strobe signal.
Extended shutter (Knee points): This feature allows for multiple-slope-exposure captures to enable a larger dynamic range.
Lookup Table (LUT): This feature allows a user-specified lookup table to be applied to the image data, enabling custom filtering and image processing.
Automatic Region of Interest (Auto ROI): This feature applies Auto or One Shot settings (like White Balance) to a specific area within the current region of interest (ROI).
Pixel Addressing: The Pixel Addressing feature controls the number of pixels that are read from the ROI. With Pixel Addressing, you can decimate, averaging, bin or resample an image.
Flip and Rotate: These features allow the image to be flipped and/or rotated.
Descriptors: A descriptor is a collection of camera feature properties that is applied to a frame. Since each frame can have a unique descriptor, custom descriptors can be used to change camera settings on a frame-by-frame basis for each frame in the video stream.
Imager Clock Divisor: This feature will reduce a camera's range of supported frame rates, by a user-specified factor. This feature is most useful if your computer is not able to process the frames (due to resource limitations) at even the lowest frame rate setting.
Extensions use Advanced Feature CSRs to inquire and control the functionality of the feature.