Repository: huggingface/transformers
Pull request: Fix loading issue in Sam3

# What does this PR do?

Fix loading in Sam3 which currently doesn't match the state dict keys from checkpoint. Adding a correct base model prefix will add it to all state dict keys, making the ckpt load-able

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Fixes # (issue)


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Changed files:
filename: src/transformers/models/sam3_tracker_video/modeling_sam3_tracker_video.py
patch: @@ -683,7 +683,7 @@ class Sam3TrackerVideoSegmentationOutput(ModelOutput):
 @auto_docstring
 class Sam3TrackerVideoPreTrainedModel(PreTrainedModel):
     config_class = Sam3TrackerVideoConfig
-    base_model_prefix = "sam3_tracker_video"
+    base_model_prefix = "tracker_model"
     main_input_name = "pixel_values"
     input_modalities = "video"
     _supports_sdpa = True

filename: src/transformers/models/sam3_tracker_video/modular_sam3_tracker_video.py
patch: @@ -329,7 +329,7 @@ class Sam3TrackerVideoSegmentationOutput(Sam2VideoSegmentationOutput):
 
 
 class Sam3TrackerVideoPreTrainedModel(Sam2VideoPreTrainedModel):
-    pass
+    base_model_prefix = "tracker_model"
 
 
 class Sam3TrackerVideoVisionRotaryEmbedding(Sam2VideoVisionRotaryEmbedding):