Debugging DepthAI pipeline

Currently, tools for debugging the DepthAI pipeline are limited. We plan on creating a software that would track all messages and queues, which would allow users to debug a “frozen” pipeline much easier, which is usually caused by a filled up blocking queue.

DepthAI debugging level

You can enable debugging by changing the debugging level. It’s set to warning by default.

Level

Logging

critical

Only a critical error that stops/crashes the program.

error

Errors will not stop the program, but won’t complete the action. Examples:
  • When ImageManip cropping ROI was out of bounds, error will get printed and the cropping won’t take place

  • When NeuralNetwork gets a frame whose shape (width/heigth/channel) isn’t that of the .blob

warn

Warnings are printed in cases where user action could improve certain behavior/fix it. Example:
  • When API changes, the old API style will be deprecated and warning will be shown to the user.

info

Will print information about CPU/RAM consumption, temperature, CMX slices and SHAVE core allocation.

debug

Useful especially on starting and stopping the pipeline. Debug will print:
  • Information about device initialization eg. Pipeline JSON, firmware/bootloader/OpenVINO version

  • How device/XLink is being closed/disposed

trace

Trace will print out a Message whenever one is received from the device.

Debugging can be enabled either in code:

with dai.Device() as device: # Initialize device
    # Set debugging level
    device.setLogLevel(dai.LogLevel.DEBUG)
    device.setLogOutputLevel(dai.LogLevel.DEBUG)

Where setLogLevel sets verbosity which filters messages that get sent from the device to the host and setLogOutputLevel sets verbosity which filters messages that get printed on the host (stdout). This difference allows to capture the log messages internally and not print them to stdout, and use those to eg. display them somewhere else or analyze them.

You can also enable debugging using an environmental variable DEPTHAI_LEVEL:

DEPTHAI_LEVEL=debug python3 script.py
$env:DEPTHAI_LEVEL='debug'
python3 script.py

# Turn debugging off afterwards
Remove-Item Env:\DEPTHAI_LEVEL
set DEPTHAI_LEVEL=debug
python3 script.py

# Turn debugging off afterwards
set DEPTHAI_LEVEL=

Script node logging

Currently, the best way to debug a behaviour inside the Script node, is to use node.warn('') logging capability. This will send the warning back to the host and it will get printed to the user. Users can also print values, such as frame sequence numbers, which would be valuable when debugging on-device frame-syncing logic.

script = pipeline.create(dai.node.Script)
script.setScript("""
    buf = NNData(13)
    buf.setLayer("fp16", [1.0, 1.2, 3.9, 5.5])
    buf.setLayer("uint8", [6, 9, 4, 2, 0])
    # Logging
    node.warn(f"Names of layers: {buf.getAllLayerNames()}")
    node.warn(f"Number of layers: {len(buf.getAllLayerNames())}")
    node.warn(f"FP16 values: {buf.getLayerFp16('fp16')}")
    node.warn(f"UINT8 values: {buf.getLayerUInt8('uint8')}")
""")

Code above will print the following values to the user:

[Script(0)] [warning] Names of layers: ['fp16', 'uint8']
[Script(0)] [warning] Number of layers: 2
[Script(0)] [warning] FP16 values: [1.2001953125, 1.2001953125, 3.900390625, 5.5]
[Script(0)] [warning] UINT8 values: [6, 9, 4, 2, 0]

Got questions?

We’re always happy to help with code or other questions you might have.