The output from snpe-net-run is already de-quantized to float32. This is the equivalent raw buffer from the ONNX equivalent which can be taken for post-processing to extract the bounding boxes.

You may further refer to the following resource to understand the inference flow with Yolov8 using SNPE,

https://github.com/quic/qidk/blob/master/Model-Enablement/Model-Accuracy-Mixed-Precision/Accuracy_Analyzer_YoloV8.ipynb