Implementation of `torchaudio.backend` missing

[kaiidams]

#805

We have stub functions torchaudio.save() and torchaudio.load(), however, we don't have implementation of https://github.com/dotnet/TorchSharp/blob/main/src/TorchAudio/AudioBackend.cs

Similar issues with #471
TorchVision uses SkiaSharp to implement IO.

[alinpahontu2912]

@kaiidams Thank you for reporting this issue regarding the missing implementation of torchaudio.backend. We appreciate your efforts in bringing attention to the stub functions torchaudio.save() and torchaudio.load(), as well as the related concerns with AudioBackend.

Since it's been over two years, we wanted to check in and see if this issue is still relevant for you or if it has been resolved in the meantime. TorchSharp has evolved significantly during this period, and we’d love to hear any updated information you might have. Your feedback is invaluable in helping us improve!