权重改为fp32, 其他部分保持bf16

目前参数--encoder_mode有三种选择:
1. fp32: 全部使用fp32, 适合显存充足的情况
2. autocast: 使用torch.cuda.amp.autocast自动混合精度, 稍微快一些, psnr下降较多
3. bf16_full: 全部使用bf16, 精度较高

scripts/evaluation/world_model_interaction.py

@@ -772,10 +772,34 @@ def image_guided_synthesis_sim_mode(
     with profiler.profile_section("synthesis/conditioning_prep"):
         img = observation['observation.images.top'].permute(0, 2, 1, 3, 4)
         cond_img = rearrange(img, 'b o c h w -> (b o) c h w')[-1:]
-        embedder_ctx = nullcontext()
         if getattr(model, "encoder_bf16", False) and model.device.type == "cuda":
-            embedder_ctx = torch.autocast("cuda", dtype=torch.bfloat16)
-        with embedder_ctx:
+            if getattr(model, "encoder_mode", "autocast") == "autocast":
+                preprocess_ctx = torch.autocast("cuda", enabled=False)
+                with preprocess_ctx:
+                    cond_img_fp32 = cond_img.float()
+                    if hasattr(model.embedder, "preprocess"):
+                        preprocessed = model.embedder.preprocess(cond_img_fp32)
+                    else:
+                        preprocessed = cond_img_fp32
+
+                if hasattr(model.embedder,
+                           "encode_with_vision_transformer") and hasattr(
+                               model.embedder, "preprocess"):
+                    original_preprocess = model.embedder.preprocess
+                    try:
+                        model.embedder.preprocess = lambda x: x
+                        with torch.autocast("cuda", dtype=torch.bfloat16):
+                            cond_img_emb = model.embedder.encode_with_vision_transformer(
+                                preprocessed)
+                    finally:
+                        model.embedder.preprocess = original_preprocess
+                else:
+                    with torch.autocast("cuda", dtype=torch.bfloat16):
+                        cond_img_emb = model.embedder(preprocessed)
+            else:
+                with torch.autocast("cuda", dtype=torch.bfloat16):
+                    cond_img_emb = model.embedder(cond_img)
+        else:
             cond_img_emb = model.embedder(cond_img)
 
         if model.model.conditioning_key == 'hybrid':
@@ -788,7 +812,11 @@ def image_guided_synthesis_sim_mode(
 
         if not text_input:
             prompts = [""] * batch_size
-        cond_ins_emb = model.get_learned_conditioning(prompts)
+        encoder_ctx = nullcontext()
+        if getattr(model, "encoder_bf16", False) and model.device.type == "cuda":
+            encoder_ctx = torch.autocast("cuda", dtype=torch.bfloat16)
+        with encoder_ctx:
+            cond_ins_emb = model.get_learned_conditioning(prompts)
         target_dtype = cond_ins_emb.dtype
 
         cond_img_emb = model._projector_forward(model.image_proj_model,
@@ -916,15 +944,18 @@ def run_inference(args: argparse.Namespace, gpu_num: int, gpu_no: int) -> None:
         diffusion_autocast_dtype = torch.bfloat16
         print(">>> diffusion backbone set to bfloat16")
 
-    encoder_dtype = torch.float32
-    if args.encoder_dtype == "bf16":
-        encoder_dtype = torch.bfloat16
+    encoder_mode = args.encoder_mode
+    encoder_bf16 = encoder_mode in ("autocast", "bf16_full")
+    encoder_weight_dtype = torch.bfloat16 if encoder_mode == "bf16_full" else torch.float32
     if hasattr(model, "cond_stage_model") and model.cond_stage_model is not None:
-        model.cond_stage_model.to(dtype=encoder_dtype)
+        model.cond_stage_model.to(dtype=encoder_weight_dtype)
     if hasattr(model, "embedder") and model.embedder is not None:
-        model.embedder.to(dtype=encoder_dtype)
-    model.encoder_bf16 = args.encoder_dtype == "bf16"
-    print(f">>> encoder dtype set to {args.encoder_dtype}")
+        model.embedder.to(dtype=encoder_weight_dtype)
+    model.encoder_bf16 = encoder_bf16
+    model.encoder_mode = encoder_mode
+    print(
+        f">>> encoder mode set to {encoder_mode} (weights={encoder_weight_dtype})"
+    )
 
     if hasattr(model, "projector_bf16"):
         model.projector_bf16 = args.projector_dtype == "bf16"
@@ -1281,11 +1312,14 @@ def get_parser():
         help="Dtype for image/state/action projectors (autocast in forward)."
     )
     parser.add_argument(
-        "--encoder_dtype",
+        "--encoder_mode",
         type=str,
-        choices=["fp32", "bf16"],
+        choices=["fp32", "autocast", "bf16_full"],
         default="fp32",
-        help="Dtype for text/image encoders (cond_stage_model/embedder)."
+        help=
+        "Encoder precision mode for cond_stage_model/embedder: "
+        "fp32=full fp32, autocast=fp32 weights + bf16 autocast in forward, "
+        "bf16_full=bf16 weights + bf16 forward."
     )
     parser.add_argument(
         "--n_action_steps",

unitree_g1_pack_camera/case1/run_world_model_interaction.sh

@@ -23,5 +23,5 @@ dataset="unitree_g1_pack_camera"
         --perframe_ae \
         --diffusion_dtype bf16 \
         --projector_dtype bf16 \
-        --encoder_dtype bf16
+        --encoder_mode autocast #fp32/autocast/bf16_full
 } 2>&1 | tee "${res_dir}/output.log"

useful.sh

@@ -81,4 +81,29 @@ BF16 projector比FP32 projector更准的可能原因：
   这也解释了为什么你看到 BF16 projector 反而更准。
 
 embedder：
-  改成 autocast only（权重 FP32，预处理 FP32，仅主干 BF16）
+  改成 autocast only（权重 FP32，预处理 FP32，仅主干 BF16）
+
+   - 效果差的那次：encoder autocast set to bf16 (weights=fp32)
+    也就是“权重 FP32 + autocast BF16（我现在的 autocast only 方案）”
+  - 效果好的那次：cond_stage_model / embedder param dtype: torch.bfloat16
+    也就是“权重 BF16（全 BF16）”
+
+  为什么 FP32 反而掉分大？主要是“混精度路径不一致”：
+
+  1. autocast only 不是等价于 full BF16
+     autocast 会把部分算子留在 FP32（比如 LayerNorm / Softmax），另一部分用 BF16；
+     这会让 encoder 输出分布和“全 BF16”不一样，尤其当扩散主干也是 BF16 时，条件向量分布一偏就会影响 PSNR。
+  2. 先 FP32 计算再转 BF16
+     encoder 的输出最后还是要拼到 BF16 主干里，等于“先高精度 → 再截断”。
+     训练时如果你用的是 BF16，模型更适应“低精度直接计算”的分布。
+  3. 你的现象和 projector 一样
+     你已经观察到 projector BF16 更准，这说明模型很可能“更偏好一致的 BF16 路径”。
+
+  结论：
+  对你这个模型，full BF16（权重 BF16）更匹配训练分布，反而 PSNR 更高。
+
+  如果你要我改回“bf16=全 BF16（权重 BF16）”，并且保留现在的 autocast only 作为可选模式，我可以这样做：
+
+  1. 新增 --encoder_mode {fp32, autocast, bf16_full}
+  2. bf16_full = 权重 BF16 + 前向 BF16
+  3. autocast = 权重 FP32 + 仅主干 autocast（现在的实现）