Hi,
I am using a OAK-D Pro W PoE since a few days and I have an issue when trying to calculate properties of the depth frame on the camera using the script node (I am also not a specialist in coding - therefore sorry in advance).
On the host everything works fine: So I managed to filter (only allow depth values in a certain range) and calculate some statistics (e.g. mean, variance, ...), since getFrame returns a numpy array which allows me to perform the filtering/statistics. I.e.:
depthFrame = frame.getFrame()
depthFrameSize = np.count_nonzero(~np.isnan(depthFrame))
inRange = (minDepth <= depthFrame) & (depthFrame <= maxDepth)
depthROI = depthFrame[inRange]
depthROISize = np.count_nonzero(~np.isnan(depthROI))
if depthROISize > 0:
depthROIVar = np.var(depthROI)
depthROIAvg = np.mean(depthROI)
In the next step I tried to move this into the script node in order to make the calculation on the camera.
So I managed to pass the depth frames to a script node. But within the script node I was not able to perform the filtering and statistics up to now. Maybe anyone give me some hints how to do the same in the script as I managed on the host using numpy functions.
Here is what I did so far:
stereo = pipeline.createStereoDepth()
script = pipeline.create(dai.node.Script)
stereo.depth.link(script.inputs['depthframes'])
script.inputs['depthframes'].setBlocking(False)
script.inputs['depthframes'].setQueueSize(1)
script.setScript("""
import json
while True:
frame = node.io['depthframes'].get()
framedata = frame.getData() # should be a 1D byte array
#TODO: filter the depth frame by min/max
#TODO: calculate mean/variance of the filtered depth frame
# write results on json dict and dump it to output
b = Buffer(300)
dict = {"mean": mean, "var": var}
b.setData(json.dumps(dict).encode('utf-8'))
node.io['out'].send(b)
""")
xout = pipeline.create(dai.node.XLinkOut)
xout.setStreamName('scriptout')
script.outputs['out'].link(xout.input)
- Within the script node I am even not sure how to treat the 1D byte array, i.e. I do not even know how to get a value of the depth frame on a specific coordinate, e.g. how to access for instance the value of the depth frame on pixel (0,0), since the 1D byte array has a structure I do not understand up to now.
So any comments and hints are welcome. Thanks a lot.
