259SDK (Software development Kit)
© 2010 Thorlabs
7.3.88
is_SetFrameRate
Syntax
INT is_SetFrameRate (HIDS hCam, double FPS, double* newFPS)
Description
Using is_SetFrameRate(), you can set the sensor frame rate in freerun mode (live mode). Since
this value depends on the sensor timing, the exposure time actually used may slightly deviate from
the value set here. After you have called the function, the actual frame rate is returned through the
newFPS parameter.
If the frame rate is set too high, it might not be possible to transfer every single frame. In this case,
the effective frame rate may vary from the set value.
For minimum and maximum frame rates as well as other sensor-based dependencies, please refer
to Specifications: Sensors chapter.
The use of the following functions will affect the frame rate:
is_SetPixelClock()
is_SetOptimalCameraTiming()
is_SetAOI() (if the image size is changed)
is_SetSubSampling()
is_SetBinning()
Changes made to the window size or the read-out timing (pixel clock frequency) also affect the
defined frame rate . For this reason, you need to call is_SetFrameRate() again after such
changes.
Newer driver versions sometimes allow an extended value range for the frame rate setting. We
recommend to query the value range every time and set the frame rate explicitly.
Changes to the frame rate affect the value ranges of the exposure time. After executing
is_SetFrameRate(), calling the function is_SetExposureTime() is recommended in order to
keep the defined camera settings.
Input Parameters
Desired frame rate in frames per second (fps)
Only returns the current frame rate in the newFPS
parameter.
Returns the default frame rate.
Returns the frame rate actually set.
Return Values
Function executed successfully
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