Possible class label order mismatch in AED model yamnet_e1024_64x96_tl_qdq_int8.onnx (ESC-10)
We have been evaluating the pre-trained model yamnet_e1024_64x96_tl_qdq_int8.onnx from the STM32 Model Zoo (ESC-10 variant) and noticed a potential discrepancy between the class label order in the provided YAML configuration and the actual output behaviour observed on target.
While the model itself appears to perform well, the mapping between output indices and class names does not seem to match the order documented in the YAML file.
Observed behaviour:
The YAML file lists the classes as:
0: dog
1: chainsaw
2: crackling_fire
3: helicopter
4: rain
5: crying_baby
6: clock_tick
7: sneezing
8: rooster
9: sea_waves
However, on our target, the outputs appear to correspond to the following order:
0: chainsaw
1: clock_tick
2: crackling_fire
3: crying_baby
4: dog
5: helicopter
6: rain
7: rooster
8: sea_waves
9: sneezing
This is consistent across multiple input samples, which makes us suspect a systematic label remapping rather than random misclassification.
Preliminary hypothesis:
We suspect that this could be caused by an ALPHABETICAL REORDERING of class labels somewhere in the training or export pipeline, for example through the use of sklearn.preprocessing.LabelEncoder or a similar mechanism. The YAML may preserve the original dataset order while the actual model output follows a different ordering.
At this stage this is only an assumption based on our observations. We would like to verify whether other users have noticed similar behaviour or whether there is additional documentation clarifying the correct output label order for this model.
Impact (if confirmed):
If the label order in the YAML does not match the actual model output, anyone deploying this model and using the YAML class_names for inference would obtain systematically incorrect class assignments, even though the model accuracy itself is not affected.
Request:
We would appreciate it if the ST team or community members could:
-
confirm whether this is a known issue,
-
clarify the correct output label mapping,
-
or advise whether the YAML file should be updated accordingly.
Model: audio_event_detection/yamnet/ST_pretrainedmodel_public_dataset/esc10/yamnet_e1024_64x96_tl
File: yamnet_e1024_64x96_tl_qdq_int8.onnx
