Specifications
Page 26
Prosilica GB Technical Manual V2.2.6
Frame memory
Normally, an image is captured and transported in consecutive steps. The image is
taken, read out from the sensor, digitized and sent over the GigE network. Prosilica
GB cameras are equipped with an image buffer. The memory operates according to
the FIFO principle. Specification tables show how many frames can be stored by
each model.
Resolution and ROI frame rate
Resolution and ROI frame rate is listed after the specification table. The resulting
frame rate from changing sensor height from full image to a single line. Unless
otherwise noted, sensors do not give an increase in readout speed with a
reduction in width. However, in cases where a camera is limited by frame rate due
to bandwidth restrictions, a reduction in width will give a frame rate increase.
Cameras with a “burst mode” frame rate are able to output more data than the
maximum available bandwidth (124 MBps), and will see a frame rate increase with
a reduction in width.
Number of frames
The number of frames (
StreamHoldCapacity
) depends on resolution, pixel
format, and GVSP packet size. The stated number of frames is typical for full
resolution, Mono8/Bayer8, and a
GevSCPSPacketSize
=
8192
bytes per packet.
Resolution and ROI measurements
•
Data was generated using
StreamBytesPerSecond
=
124
MBps
(full
bandwidth), minimum exposure, full resolution, and an 8-bit pixel format.
Frame rate may be lower if using network hardware incapable of 124 MBps.
•
For maximum speed advantage on quad-tap CCD sensors, ROIs are center
image, where feature
OffsetY
= (full sensor height – ROI height)/2.
•
BinningVertical
is vertical row summing of charge on CCD sensors before
readout. The frame rate for an ROI at the same effective height as binning is
slower because the CCD still needs to read out the “fast readout rows” in ROI
mode.
