Holdimg mode – ALLIED Vision Technologies Pike F-1600 User Manual
Page 192
Description of the data path
PIKE Technical Manual V5.1.2
192
Deferred image transport is especially useful for multi-camera applications:
Assuming several cameras acquire images concurrently. These are stored in the
built-in image memory of every camera. Until this memory is full, the limiting
factor of available bus bandwidth, DMA- or ISO-channel is overcome.
Image transfer is controlled from the host computer by addressing individual
cameras one after the other and reading out the desired number of images.
HoldImg mode
By setting the HoldImg flag, transport of the image over the 1394 bus is
stopped completely. All captured images are stored in the internal ImageFiFo.
The camera reports the maximum possible number of images in the FiFoSize
variable.
Note
Configuration
To configure this feature in an advanced register: See
163: Advanced register: Deferred image transport
Note
•
Pay attention to the maximum number of images that can
be stored in FiFo. If you capture more images than the
number in FiFoSize, the oldest images are overwritten.
•
The extra SendImage flag is set to true to import the
images from the camera. The camera sends the number of
images set in the NumOfImages parameter.
•
If NumOfImages is 0, all images stored in FIFO will be
sent.
•
If NumOfImages is not 0, the corresponding number of
images will be sent.
•
If the HoldImg field is set to false, all images in
ImageFIFO will be deleted. No images will be sent.
•
The last image in the FiFo will be corrupted, when simul-
taneously used as input buffer while being read out. In
this case read out one image less than max. buffer size.
•
NumOfImages is incremented after an image was read
out of the sensor and therefore stored into the onboard
image FIFO.
•
NumOfImages is decremented after the last isochronous
packet of an image was handed over to the IEEE1394
chipset of the camera.