Specifications
24
Prosilica GX Technical Manual V2.3.1
Bandwidth limiting of frame rate
There are several factors that limit the frame rate of a camera, for example, input
trigger speed and mode, exposure time, sensor readout time, and available
bandwidth. For the following discussion and charts we assume input trigger
settings and exposure time are set so as not to limit the frame of the camera. This
leaves sensor readout time, the time to physically output the charge off a camera
sensor, and available bandwidth. In most cases, the sensor readout time dictates
the true frame rate of a camera, unless the amount of transmitted data exceeds
what is available on the GigE interface.
In the example chart below, the frame rate for a 16-bit pixel format is given on a
Prosilica GX1050 camera. The upper line shows the frame rate in dual GigE mode,
where no bandwidth limitation occurs. The lower line shows the frame rate in
single GigE mode, where bandwidth limitation occurs after a data threshold of 124
Mbit/s. This is the shaded region below, occurring at an image height greater than
200 pixels.
Figure 1: Illustration of bandwidth limiting: frame rate vs. height for Prosilica
GX1050 in single interface GigE configuration - 16-bit pixel format
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1050
Fr
ame Rate [fps]
Height [pixels]
Dual GigE - 16 bit
Single GigE - 16 bit
Bandwidth limited
