Issues in Pascal Context GT Visualization

[unknownpersonai]

Bug Report: Issues with Pascal Context GT Visualization

Steps to Reproduce the Bug:

Run the command tools/visualize_data.
Observe that visualize.py in the utils folder uses an outdated numpy dtype, leading to overflow issues.
Code and Changes:
Refer to the details in the failed pull request: #5391.

Observation:

The visualization incorrectly displays the image. For instance:
The class ID should be train (359) but overflows and maps to fly (103) due to the calculation 359 - 256 = 103.
Expected Behavior:
Handle more than 256 classes correctly without overflow.
(Note: Pascal Context contains 459 classes, causing the overflow issue.)

Environment:

Python: 3.10
Numpy: 1.22.4
PyTorch: 1.13.1
Additional Notes:
Simplify the reproduction steps to avoid dependencies on private datasets. Ensure the d type supports the required range of class IDs.