Repository: huggingface/transformers
Pull request: SAM3 Video: Remove call to pin_memory if the target device is not CUDA

# What does this PR do?
Remove the call to pin_memory if the target device is not CUDA. 

This library has been recommended for people who can't use the main SAM3 repo due to CUDA requirement, for example on MPS: https://huggingface.co/facebook/sam3/discussions/11 

I believe pin_memory is only effective for CUDA type devices. There hasn't been movement on pin_memory fix for MPS since 2022: https://github.com/pytorch/pytorch/issues/86060 

Transformers is the easiest way to run SAM3 on a Mac, and this change would let us properly use SAM3 Video. 


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Fixes # (issue)


## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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@yonigozlan


Changed files:
filename: src/transformers/models/sam3_video/processing_sam3_video.py
patch: @@ -340,7 +340,7 @@ def postprocess_outputs(
 
             # slice those valid entries from the original outputs
             keep_idx = torch.nonzero(keep, as_tuple=True)[0]
-            keep_idx_gpu = keep_idx.pin_memory().to(device=out_binary_masks.device, non_blocking=True)
+            keep_idx_gpu = keep_idx.to(device=out_binary_masks.device, non_blocking=True)
 
             out_obj_ids = torch.index_select(out_obj_ids, 0, keep_idx)
             out_probs = torch.index_select(out_probs, 0, keep_idx)