feat: 更新框架，新增数据及定义和backbone

roboimi/vla/models/backbones/siglip2.py

@@ -0,0 +1,37 @@
+from transformers import SiglipVisionModel
+from roboimi.vla.core.interfaces import VLABackbone
+from torchvision import transforms
+
+class SigLIP2(VLABackbone):
+    def __init__(
+            self,
+            model_name = "google/siglip2-base-patch16-384",
+            freeze: bool = True,
+    ):
+        super().__init__()
+
+        self.vision_model = SiglipVisionModel.from_pretrained(model_name)
+        self.transform = transforms.Compose([
+            transforms.Resize((384, 384), antialias=True),
+            transforms.Normalize(mean=[0.5, 0.5, 0.5], std=[0.5, 0.5, 0.5])
+        ])
+
+        if freeze:
+            self._freeze_parameters()
+
+    def _freeze_parameters(self):
+        print("❄️ Freezing Vision Backbone parameters")
+        for param in self.vision_model.parameters():
+            param.requires_grad = False
+        self.vision_model.eval()
+
+    def forward(
+            self,
+            images
+    ):
+        # images: (B, C, H, W), 归一化到 [0, 1]
+        images = self.transform(images)  # 归一化到 [-1, 1]
+
+        outputs = self.vision_model(pixel_values=images)
+
+        return outputs.last_hidden_state