51
11.5 Frame Delay
Another approach for packet sorting in multi-camera operation is the so-called
Frame De-
lay, which was introduced to Baumer Gigabit Ethernet cameras in hardware release 2.1.
Due to the fact, that the currently recorded image is stored within the camera and its
transmission starts with a predefined delay, complete images can be transmitted to the
PC at once.
The following figure should serve as an example:
Due to process-related circumstances, the image acquisitions of all cameras end at the
same time. Now the cameras are not trying to transmit their images simultaniously, but –
according to the specified transmission delays – subsequently. Thereby the first camera
starts the transmission immediately – with a transmission delay "0".
11.5.1 Time Saving in Multi-Camera Operation
As previously stated, the Frame delay feature was especially designed for multi-camera
operation with employment of different camera models. Just here an significant accelera
-
tion of the image transmission can be achieved:
For the above mentioned example, the employment of the transmission delay feature re-
sults in a time saving – compared to the approach of using the inter paket gap – of approx.
45% (applied to the transmission of all three images).
◄ Figure 34
Principle of the Frame
delay.
◄ Figure 35
Comparison of frame
delay and inter packet
gap, employed for a
multi-camera system
with different camera
models.
