Handling source ordering

[csteinmetz1]

Seeing some weirdness in how source ordering is handled. In cfg/hdemucs.yaml we can define the ordering. However, there are also defaults defined in utils/__init__.py. In the lightning module seems like it uses the ordering from the defaults. I saw this behavior when I loaded only the base model from the checkpoint and not the lightning module, which resulted in the ordering of the source labels being swapped.

Thoughts on the best way to handle source ordering so we don't have it defined in multiple places?

[yoyolicoris]

The source ordering in the config is meaningless, because of the sorting operation inside lightning model.
https://github.com/yoyololicon/mdx23-aim-playground/blob/f3ffa7e7bb3831410077a77db2b702b69cc08332/lightning/waveform.py#L35
You can imagine the sources as a set, not a list.
The order always follows the one defined in utils.
Is there any situation that needs ordering in the config file?

[csteinmetz1]

The issue I observed was when I loaded our demucs from the checkpoint without using the lightning module the sources in model.sources used the ordering from the config whereas when loading checkpoint via the lightning module the ordering was correct (based on the ordering in the utils).

As long as we default to ordering inside the utils it seems okay, and will set the ordering based on that when loading checkpoints.

[yoyolicoris]

Ah, I see where you were talking.
Notice that other models don't have the same attribute sources like HDemucs from torchaudio.
Using the targets from the config would be better than model.sources.
I will add some comments to #18 later.

[yoyolicoris]

Close due to inactive.