The stream callback is triggered each time a frame buffer is completely filled and the execution of the previous callback has already finished. However, the stream callback cannot reliably handle update rates exceeding 10,000 times per second, depending on CPU and software capabilities.

To resolve this limitation, you can accumulate multiple frames/lines into a single buffer using the 'SegmentsPerBuffer' parameter on the grabber. This approach reduces the callback frequency, as the stream callback will be invoked only when the buffer containing the specified number of frames/lines is completely filled.

Segments Per Buffer

API

To configure the 'SegmentsPerBuffer' parameter via Vision Point API:

GUI

To configure the 'SegmentsPerBuffer' parameter in Vision Point GUI:

1. Go to Frame Grabber → Extended Stream Features
2. Navigate to: Camera Selector → Image Format Control → Segments Per Buffer

Remarks

1. Segments Per Buffer parameter must be set only after a camera has been connected and opened (camera detection process).  
   2. The default value of "Segments Per Buffer" is `1`, meaning the stream callback will occur for every single frame/line captured.  
   3. "Segments Per Buffer" is a grabber-level setting applied per camera. For details on configuring grabber parameters per camera, refer to the "Camera Selector" section in the *KAYA Frame Grabber Feature Guide* document.  
   4. Memory Consideration:  
      - Increasing the "Segments Per Buffer" value requires adjusting the size of the acquisition buffers accordingly.  
      - In this case, the required memory, reported by the function `KYFG_StreamGetInfo()` with the `KY_STREAM_INFO_PAYLOAD_SIZE` info command, will increase proportionally.  
      - For example, if a camera has a frame size of 640x480 and "Segments Per Buffer" is set to `10`, the buffer size will increase to accommodate `10` frames.