Files
lerobot/tests/policies/vla_jepa/test_vla_jepa.py
T
Maxime Ellerbach 2e9cd87bbd feat(policies): add VLA-JEPA (#3568)
* first commit

* feat(policies): add VLA-JEPA

* feat(policies): add VLA-JEPA

* support vla_jepa

* (feat)policies: add VLA-JEPA

* linting

* adding deps to pyproject.toml

* updating uv lock

* adding guards to avoid needing transformers and diffusers for type checking and basic tests

* fixing action and state dim

* fix warnings with qwen processor kwargs

* fixing wm_loss not propagating

* adjusting obs steps, tublets size to match original implementation

* some more fixes to be closer to the original implem

* adding more tests to ensure good coverage

* align VLA-JEPA architecture with original checkpoint

- Remove stale `action_num_heads` / `action_attention_head_dim` config fields;
  DiT head dimensions are now always derived from the preset (DiT-B/L/test).
- Add `num_target_vision_tokens` and `action_max_seq_len` config fields required
  by the action head's future-token embedding and positional embedding tables.
- Fix default `qwen_model_name` to 2B (matches all released checkpoints).
- Rename `ActionEncoder` attrs w1/w2/w3 → layer1/layer2/layer3 to match
  checkpoint key names; replace `nn.Sequential` decoder/state-encoder with
  `_MLP2` (layer1/layer2 naming).
- Fix `VLAJEPAActionHead` to size ActionEncoder and StateEncoder at `inner_dim`
  (DiT input width) rather than `action_hidden_size` (DiT output width).
- Rename `DiT.blocks` → `transformer_blocks` and `attn` → `attn1` to match
  checkpoint; add alternating cross/self attention (even blocks cross-attend to
  Qwen context, odd blocks self-attend).
- Add `DiT-test` preset for unit tests.
- Rewrite `ActionConditionedVideoPredictor` with explicit ViT-style blocks
  (`_PredictorBlock` with fused qkv) to match checkpoint structure; rename
  `encoder`/`norm`/`proj` → `predictor_blocks`/`predictor_norm`/`predictor_proj`.

* propagate action_is_pad masking through VLA-JEPA policy pipeline

Pass the `action_is_pad` tensor from the batch through to the action head
so padded timesteps are excluded from the flow-matching loss.

* update VLA-JEPA tests for arch changes and action_is_pad

- Switch conftest to use `action_model_type="DiT-test"` now that
  `action_num_heads` / `action_attention_head_dim` have been removed.
- Add action_head tests covering fully-padded loss (zero) and equivalence
  of action_is_pad=None vs all-zeros mask.
- Remove obsolete `test_native_to_lerobot_wm_only` test.

* add VLA-JEPA documentation

Covers architecture overview, pretrained checkpoints, config reference,
training/eval commands for LIBERO-10, and guidance on fine-tuning for
single-camera datasets.

* add one-shot script to convert ginwind/VLA-JEPA checkpoints to safetensors (will remove once migrated)

* make default params more aligned with paper and pretrained models
- adding possibility of freezing qwen backbone and world model
- added tests for weight loading

* trying out to re-init the action head to avoid pretraining dimension mismatch

* allow different state dim and action dim

* removing missleading future_action_window_size to just use chunk_size

* lots of changes to make existing weights work, need to massively refactor the pre and post processing

* refactoring into using pre and post processor

* pre-commit cleanup

* fixing doc defaults args

Signed-off-by: Maxime Ellerbach <maxime@ellerbach.net>

* adressing dtype zeros issue

* adding guard for diffusers

* fixing training and exal examples

* trying to close success rate gap

* fix qwen norm layer output libero eval is now as expected

* adding instructions for different embodiement + fixing some tests

* smol fix to avoid having default CPU device when training

* fixing misconception about multiview / singleview handling

* removing conversion script

* adding licences

* adding .mdx docs and shortening polivy_vla_jepa_README.md

* removing useless pre-processor

* cleanup

* removing swish in favor of silu

* adding configuration gripper index and threshold

* fixing simlink

---------

Signed-off-by: Maxime Ellerbach <maxime@ellerbach.net>
Co-authored-by: ginwind <ginwind@mail.ustc.edu.cn>
2026-06-04 19:22:51 +02:00

599 lines
22 KiB
Python

#!/usr/bin/env python
from __future__ import annotations
import os
from copy import deepcopy
import numpy as np
import pytest
import torch
from torch import Tensor
pytest.importorskip("transformers")
pytest.importorskip("diffusers")
pytestmark = pytest.mark.filterwarnings(
"ignore:In CPU autocast, but the target dtype is not supported:UserWarning"
)
from conftest import ( # noqa: E402
ACTION_DIM,
ACTION_HORIZON,
BATCH_SIZE,
EXPECTED_ACTION_CHUNK_SHAPE,
EXPECTED_SELECT_ACTION_SHAPE,
IMAGE_SIZE,
N_ACTION_STEPS,
QWEN_HIDDEN_SIZE,
STATE_DIM,
make_config,
make_inference_batch,
make_train_batch,
set_seed_all,
)
from lerobot.policies.vla_jepa.configuration_vla_jepa import VLAJEPAConfig # noqa: E402
from lerobot.policies.vla_jepa.modeling_vla_jepa import VLAJEPAPolicy # noqa: E402
from lerobot.utils.constants import ACTION # noqa: E402
PRETRAINED_REPO_ID = "ginwind/VLA-JEPA"
PRETRAINED_SUBFOLDER = "LIBERO"
# extended hub tests load the full converted safetensors checkpoints (~5 GB) and are
# skipped by default. Set VLA_JEPA_EXTENDED=1 to opt in.
_VLA_JEPA_EXTENDED = os.environ.get("VLA_JEPA_EXTENDED", "0") != "0"
extended_test = pytest.mark.skipif(not _VLA_JEPA_EXTENDED, reason="Set VLA_JEPA_EXTENDED=1 to run hub tests")
# ---------------------------------------------------------------------------
# Core training / inference tests
# ---------------------------------------------------------------------------
def test_training_forward_pass(patch_vla_jepa_external_models: None) -> None:
set_seed_all(42)
policy = VLAJEPAPolicy(make_config())
policy.train()
batch = make_train_batch()
batch_before = deepcopy(batch)
loss, logs = policy.forward(batch)
assert loss.shape == ()
assert torch.isfinite(loss)
assert set(logs) == {"action_loss", "wm_loss", "loss"}
assert logs["action_loss"] > 0
assert logs["wm_loss"] >= 0
loss.backward()
assert any(p.grad is not None for p in policy.model.action_model.parameters() if p.requires_grad)
# Batch must not be mutated.
assert set(batch) == set(batch_before)
for key, value in batch.items():
if isinstance(value, Tensor):
assert torch.equal(value, batch_before[key])
else:
assert value == batch_before[key]
@pytest.mark.parametrize("batch_size", [1, 2, 4])
def test_training_forward_various_batch_sizes(patch_vla_jepa_external_models: None, batch_size: int) -> None:
set_seed_all(42)
policy = VLAJEPAPolicy(make_config())
policy.train()
loss, logs = policy.forward(make_train_batch(batch_size=batch_size))
assert torch.isfinite(loss) and loss > 0
assert set(logs) == {"action_loss", "wm_loss", "loss"}
@pytest.mark.parametrize(
"action_dim,state_dim,action_horizon",
[
(3, 4, 4),
(7, 0, 16),
(6, 8, 8),
],
)
def test_training_forward_various_dims(
patch_vla_jepa_external_models: None,
action_dim: int,
state_dim: int,
action_horizon: int,
) -> None:
set_seed_all(42)
config = make_config(action_dim=action_dim, state_dim=state_dim, action_horizon=action_horizon)
policy = VLAJEPAPolicy(config)
policy.train()
batch = make_train_batch(action_dim=action_dim, state_dim=state_dim, action_horizon=action_horizon)
loss, _ = policy.forward(batch)
assert torch.isfinite(loss) and loss > 0
@torch.no_grad()
def test_action_generation_shape(patch_vla_jepa_external_models: None) -> None:
set_seed_all(42)
policy = VLAJEPAPolicy(make_config())
policy.eval()
batch = make_inference_batch()
chunk = policy.predict_action_chunk(batch)
assert tuple(chunk.shape) == EXPECTED_ACTION_CHUNK_SHAPE
assert chunk.device.type == "cpu"
assert torch.isfinite(chunk).all()
a1 = policy.select_action(batch)
a2 = policy.select_action(batch)
assert tuple(a1.shape) == EXPECTED_SELECT_ACTION_SHAPE
assert tuple(a2.shape) == EXPECTED_SELECT_ACTION_SHAPE
assert torch.isfinite(a1).all() and torch.isfinite(a2).all()
@torch.no_grad()
@pytest.mark.parametrize("action_dim,state_dim", [(3, 4), (7, 0), (6, 8)])
def test_action_generation_various_dims(
patch_vla_jepa_external_models: None, action_dim: int, state_dim: int
) -> None:
set_seed_all(42)
config = make_config(action_dim=action_dim, state_dim=state_dim)
policy = VLAJEPAPolicy(config)
policy.eval()
batch = make_inference_batch(state_dim=state_dim)
chunk = policy.predict_action_chunk(batch)
assert chunk.shape[-1] == action_dim
assert torch.isfinite(chunk).all()
@torch.no_grad()
def test_inference_reproducibility(patch_vla_jepa_external_models: None) -> None:
set_seed_all(42)
policy = VLAJEPAPolicy(make_config())
policy.eval()
batch = make_inference_batch()
set_seed_all(123)
actions_1 = policy.predict_action_chunk(batch)
set_seed_all(123)
actions_2 = policy.predict_action_chunk(batch)
assert tuple(actions_1.shape) == EXPECTED_ACTION_CHUNK_SHAPE
assert torch.allclose(actions_1, actions_2, atol=1e-6)
@torch.no_grad()
def test_predict_action_chunk_always_finite(patch_vla_jepa_external_models: None) -> None:
policy = VLAJEPAPolicy(make_config())
policy.eval()
for seed in [0, 42, 123]:
set_seed_all(seed)
chunk = policy.predict_action_chunk(make_inference_batch())
assert torch.isfinite(chunk).all(), f"non-finite actions with seed={seed}"
# ---------------------------------------------------------------------------
# Action queue behaviour
# ---------------------------------------------------------------------------
@torch.no_grad()
def test_select_action_queue_drains_before_refill(patch_vla_jepa_external_models: None) -> None:
set_seed_all(42)
policy = VLAJEPAPolicy(make_config())
policy.eval()
batch = make_inference_batch()
# First call fills the queue (n_action_steps items) and pops one.
a1 = policy.select_action(batch)
assert len(policy._queues[ACTION]) == N_ACTION_STEPS - 1
# Second call pops from the existing queue without calling predict_action_chunk.
a2 = policy.select_action(batch)
assert tuple(a1.shape) == EXPECTED_SELECT_ACTION_SHAPE
assert tuple(a2.shape) == EXPECTED_SELECT_ACTION_SHAPE
@torch.no_grad()
def test_reset_clears_action_queue(patch_vla_jepa_external_models: None) -> None:
set_seed_all(42)
policy = VLAJEPAPolicy(make_config())
policy.eval()
policy.select_action(make_inference_batch())
assert len(policy._queues[ACTION]) > 0
policy.reset()
assert len(policy._queues[ACTION]) == 0
# ---------------------------------------------------------------------------
# Format conversion
# ---------------------------------------------------------------------------
def test_prepare_model_inputs_training_format(patch_vla_jepa_external_models: None) -> None:
from PIL import Image
policy = VLAJEPAPolicy(make_config())
examples = policy._prepare_model_inputs(make_train_batch())
assert len(examples) == BATCH_SIZE
for ex in examples:
assert set(ex) >= {"image", "video", "lang", "action", "state"}
assert len(ex["image"]) == 1 and isinstance(ex["image"][0], Image.Image)
assert ex["video"].ndim == 5 and ex["video"].dtype == np.uint8 # [V,T,H,W,C]
assert ex["action"].shape == (ACTION_HORIZON, ACTION_DIM)
assert ex["state"].shape == (1, STATE_DIM)
def test_prepare_model_inputs_inference_omits_action(patch_vla_jepa_external_models: None) -> None:
policy = VLAJEPAPolicy(make_config())
for ex in policy._prepare_model_inputs(make_inference_batch()):
assert "action" not in ex
assert "image" in ex and "video" in ex and "lang" in ex
def test_prepare_model_inputs_missing_task_uses_default(patch_vla_jepa_external_models: None) -> None:
policy = VLAJEPAPolicy(make_config())
batch = make_inference_batch()
del batch["task"]
examples = policy._prepare_model_inputs(batch)
assert all(isinstance(ex["lang"], str) and len(ex["lang"]) > 0 for ex in examples)
def test_prepare_model_inputs_string_task_broadcast(patch_vla_jepa_external_models: None) -> None:
policy = VLAJEPAPolicy(make_config())
batch = make_inference_batch()
batch["task"] = "open the drawer"
assert all(ex["lang"] == "open the drawer" for ex in policy._prepare_model_inputs(batch))
def test_prepare_model_inputs_no_state_omitted(patch_vla_jepa_external_models: None) -> None:
from lerobot.utils.constants import OBS_STATE
policy = VLAJEPAPolicy(make_config())
batch = make_inference_batch()
del batch[OBS_STATE]
assert all("state" not in ex for ex in policy._prepare_model_inputs(batch))
# ---------------------------------------------------------------------------
# Pretrained checkpoint
# Hub tests (opt-in: VLA_JEPA_EXTENDED=1)
# ---------------------------------------------------------------------------
def _make_hub_train_batch(policy: VLAJEPAPolicy, batch_size: int = 1) -> dict:
"""Build a training batch whose keys/shapes match a hub-loaded policy config."""
cfg = policy.config
batch: dict = {"task": ["pick up the cube"] * batch_size}
for key, feat in cfg.image_features.items():
h, w = feat.shape[-2], feat.shape[-1]
batch[key] = torch.rand(batch_size, cfg.num_video_frames, 3, h, w)
if cfg.robot_state_feature is not None:
batch["observation.state"] = torch.randn(batch_size, 1, cfg.robot_state_feature.shape[0])
batch[ACTION] = torch.randn(batch_size, cfg.chunk_size, cfg.action_dim)
return batch
def _make_hub_inference_batch(policy: VLAJEPAPolicy, batch_size: int = 1) -> dict:
"""Build an inference batch whose keys/shapes match a hub-loaded policy config."""
cfg = policy.config
batch: dict = {"task": ["pick up the cube"] * batch_size}
for key, feat in cfg.image_features.items():
h, w = feat.shape[-2], feat.shape[-1]
batch[key] = torch.rand(batch_size, 3, h, w)
if cfg.robot_state_feature is not None:
batch["observation.state"] = torch.randn(batch_size, cfg.robot_state_feature.shape[0])
return batch
_CP_ROOT = "lerobot"
# Each tuple: (repo_id, enable_world_model)
_HUB_VARIANTS = [
(f"{_CP_ROOT}/VLA-JEPA-LIBERO", True),
(f"{_CP_ROOT}/VLA-JEPA-Pretrain", True),
(f"{_CP_ROOT}/VLA-JEPA-SimplerEnv", False),
]
@extended_test
@pytest.mark.parametrize("repo_id,enable_world_model", _HUB_VARIANTS)
def test_hub_checkpoint_loads(repo_id: str, enable_world_model: bool) -> None:
"""Policy loads from the converted safetensors checkpoint on the Hub."""
policy = VLAJEPAPolicy.from_pretrained(repo_id)
assert policy.config.enable_world_model == enable_world_model
assert sum(p.numel() for p in policy.parameters()) > 0
@extended_test
@pytest.mark.parametrize("repo_id,enable_world_model", _HUB_VARIANTS)
def test_hub_checkpoint_forward_pass(repo_id: str, enable_world_model: bool) -> None:
"""Policy loaded from hub produces finite losses with a correctly-shaped batch."""
policy = VLAJEPAPolicy.from_pretrained(repo_id)
policy.train()
batch = _make_hub_train_batch(policy)
loss, logs = policy.forward(batch)
assert torch.isfinite(loss)
assert "action_loss" in logs
if enable_world_model:
assert "wm_loss" in logs
@extended_test
def test_hub_freeze_qwen_disables_world_model() -> None:
"""freeze_qwen=True (via cli_overrides) freezes qwen and disables the world model."""
policy = VLAJEPAPolicy.from_pretrained(f"{_CP_ROOT}/VLA-JEPA-LIBERO", cli_overrides=["freeze_qwen=true"])
assert not policy.config.enable_world_model
assert policy.model.video_predictor is None
qwen_params = list(policy.model.qwen.parameters())
assert all(not p.requires_grad for p in qwen_params)
assert any(p.requires_grad for p in policy.model.action_model.parameters())
@extended_test
def test_hub_disable_world_model_loads_simpler_env() -> None:
"""SimplerEnv checkpoint (world model disabled) loads cleanly and runs inference."""
policy = VLAJEPAPolicy.from_pretrained(f"{_CP_ROOT}/VLA-JEPA-SimplerEnv")
assert not policy.config.enable_world_model
assert policy.model.video_predictor is None
assert policy.model.video_encoder is None
@extended_test
def test_hub_libero_inference_shape() -> None:
"""select_action returns the expected shape using the LIBERO hub checkpoint."""
policy = VLAJEPAPolicy.from_pretrained(f"{_CP_ROOT}/VLA-JEPA-LIBERO")
policy.eval()
batch = _make_hub_inference_batch(policy)
action = policy.select_action(batch)
assert action.shape[-1] == policy.config.action_dim
# ---------------------------------------------------------------------------
# Postprocessor unnormalization tests
#
# These tests verify that the postprocessor pipeline (clip → unnorm → binarize)
# correctly applies MIN_MAX unnormalization after predict_action_chunk.
# ---------------------------------------------------------------------------
def _make_dataset_stats(action_dim: int = ACTION_DIM) -> dict:
"""Returns sample dataset_stats with a simple [i, i+10] range per action dim."""
from lerobot.utils.constants import ACTION
return {
ACTION: {
"min": torch.tensor([float(i) for i in range(action_dim)], dtype=torch.float32),
"max": torch.tensor([float(i) + 10.0 for i in range(action_dim)], dtype=torch.float32),
}
}
@torch.no_grad()
def test_postprocessor_unnormalizes_actions(patch_vla_jepa_external_models: None) -> None:
"""UnnormalizerProcessorStep with MIN_MAX produces the correct inverse of MIN_MAX normalization."""
from lerobot.configs.types import FeatureType, NormalizationMode, PolicyFeature
from lerobot.processor import UnnormalizerProcessorStep
from lerobot.processor.converters import policy_action_to_transition, transition_to_policy_action
from lerobot.utils.constants import ACTION
dataset_stats = _make_dataset_stats()
rng = np.random.default_rng(7)
actions_np = rng.uniform(-1.0, 1.0, (2, ACTION_HORIZON, ACTION_DIM)).astype(np.float32)
a_min = dataset_stats[ACTION]["min"].numpy()
a_max = dataset_stats[ACTION]["max"].numpy()
expected = (actions_np + 1.0) / 2.0 * (a_max - a_min) + a_min
features = {ACTION: PolicyFeature(type=FeatureType.ACTION, shape=(ACTION_DIM,))}
unnorm_step = UnnormalizerProcessorStep(
features=features,
norm_map={FeatureType.ACTION: NormalizationMode.MIN_MAX},
stats=dataset_stats,
)
actions_tensor = torch.from_numpy(actions_np)
transition = policy_action_to_transition(actions_tensor)
result = transition_to_policy_action(unnorm_step(transition)).numpy()
np.testing.assert_allclose(result, expected, rtol=1e-5, atol=1e-6)
@torch.no_grad()
def test_postprocessor_clip_clamps_before_unnorm(patch_vla_jepa_external_models: None) -> None:
"""ClipActionsProcessorStep clamps to [-1, 1] before unnormalization."""
from lerobot.configs.types import FeatureType, NormalizationMode, PolicyFeature
from lerobot.policies.vla_jepa.processor_vla_jepa import ClipActionsProcessorStep
from lerobot.processor import UnnormalizerProcessorStep
from lerobot.processor.converters import policy_action_to_transition, transition_to_policy_action
from lerobot.utils.constants import ACTION
dataset_stats = _make_dataset_stats()
a_min = dataset_stats[ACTION]["min"].numpy()
a_max = dataset_stats[ACTION]["max"].numpy()
# Deliberately out-of-range inputs
actions_np = np.array([[[2.0] * ACTION_DIM, [-3.0] * ACTION_DIM]], dtype=np.float32)
clipped = np.clip(actions_np, -1.0, 1.0)
expected = (clipped + 1.0) / 2.0 * (a_max - a_min) + a_min
features = {ACTION: PolicyFeature(type=FeatureType.ACTION, shape=(ACTION_DIM,))}
clip_step = ClipActionsProcessorStep()
unnorm_step = UnnormalizerProcessorStep(
features=features,
norm_map={FeatureType.ACTION: NormalizationMode.MIN_MAX},
stats=dataset_stats,
)
transition = policy_action_to_transition(torch.from_numpy(actions_np))
transition = clip_step(transition)
result = transition_to_policy_action(unnorm_step(transition)).numpy()
np.testing.assert_allclose(result, expected, rtol=1e-5, atol=1e-6)
@torch.no_grad()
def test_postprocessor_applied_after_predict_action_chunk(
patch_vla_jepa_external_models: None, monkeypatch: pytest.MonkeyPatch
) -> None:
"""predict_action_chunk returns raw actions; the postprocessor applies unnormalization.
Verifies the split: predict_action_chunk returns normalized actions, and calling the
postprocessor on them produces the correctly unnormalized result.
"""
from lerobot.policies.vla_jepa.processor_vla_jepa import make_vla_jepa_pre_post_processors
raw_actions = np.zeros((BATCH_SIZE, ACTION_HORIZON, ACTION_DIM), dtype=np.float32)
cfg = make_config()
cfg.clip_normalized_actions = False
cfg.binarize_gripper_action = False
policy = VLAJEPAPolicy(cfg)
policy.eval()
monkeypatch.setattr(policy.model, "predict_action", lambda *a, **kw: raw_actions.copy())
dataset_stats = _make_dataset_stats()
_, postprocessor = make_vla_jepa_pre_post_processors(cfg, dataset_stats)
batch = make_inference_batch()
chunk = policy.predict_action_chunk(batch)
# predict_action_chunk returns raw (normalized) actions
assert torch.allclose(chunk, torch.zeros_like(chunk), atol=1e-6), (
"predict_action_chunk should return raw actions without unnormalization applied."
)
# Postprocessor applies unnormalization: 0 → (0+1)/2 * (max-min) + min = 5 + i
unnormed = postprocessor(chunk)
from lerobot.utils.constants import ACTION
a_min = dataset_stats[ACTION]["min"].numpy()
a_max = dataset_stats[ACTION]["max"].numpy()
expected_first = 0.5 * (0.0 + 1.0) * (a_max[0] - a_min[0]) + a_min[0]
assert unnormed[0, 0, 0].item() == pytest.approx(expected_first, abs=1e-5)
# ---------------------------------------------------------------------------
# World-model view adjustment (padding / trimming) tests
# ---------------------------------------------------------------------------
_MULTIVIEW_NUM_FRAMES = 4 # must be >= 2 * jepa_tubelet_size (=2) for world-model tests
def _make_multiview_config(num_views: int, jepa_tubelet_size: int = 2) -> VLAJEPAConfig:
from lerobot.configs.types import FeatureType, PolicyFeature
from lerobot.utils.constants import OBS_IMAGES, OBS_STATE
config = VLAJEPAConfig(
input_features={
**{
f"{OBS_IMAGES}.cam{i}": PolicyFeature(
type=FeatureType.VISUAL, shape=(3, IMAGE_SIZE, IMAGE_SIZE)
)
for i in range(num_views)
},
OBS_STATE: PolicyFeature(type=FeatureType.STATE, shape=(STATE_DIM,)),
},
output_features={ACTION: PolicyFeature(type=FeatureType.ACTION, shape=(ACTION_DIM,))},
device="cpu",
chunk_size=ACTION_HORIZON,
n_action_steps=N_ACTION_STEPS,
action_dim=ACTION_DIM,
state_dim=STATE_DIM,
num_video_frames=_MULTIVIEW_NUM_FRAMES,
num_action_tokens_per_timestep=2,
num_embodied_action_tokens_per_instruction=3,
num_inference_timesteps=2,
action_hidden_size=QWEN_HIDDEN_SIZE,
action_model_type="DiT-test",
action_num_layers=1,
predictor_depth=1,
predictor_num_heads=2,
predictor_mlp_ratio=2.0,
jepa_tubelet_size=jepa_tubelet_size,
)
config.validate_features()
return config
def _make_multiview_train_batch(num_views: int, batch_size: int = BATCH_SIZE) -> dict:
from lerobot.utils.constants import OBS_IMAGES, OBS_STATE
batch = {
f"{OBS_IMAGES}.cam{i}": torch.rand(batch_size, _MULTIVIEW_NUM_FRAMES, 3, IMAGE_SIZE, IMAGE_SIZE)
for i in range(num_views)
}
batch[OBS_STATE] = torch.randn(batch_size, 1, STATE_DIM)
batch[ACTION] = torch.randn(batch_size, ACTION_HORIZON, ACTION_DIM)
batch["task"] = ["pick up the cube"] * batch_size
return batch
@pytest.mark.parametrize(
"num_views",
[
1, # fewer views than jepa_tubelet_size → first view duplicated
2, # exact match → unchanged
3, # more views than jepa_tubelet_size → trimmed to first two
],
)
def test_training_forward_world_model_view_adjustment(
patch_vla_jepa_external_models: None,
num_views: int,
) -> None:
"""World-model view padding/trimming must not break the training forward pass."""
set_seed_all(42)
policy = VLAJEPAPolicy(_make_multiview_config(num_views=num_views, jepa_tubelet_size=2))
policy.train()
loss, logs = policy.forward(_make_multiview_train_batch(num_views=num_views))
assert torch.isfinite(loss)
assert logs["wm_loss"] >= 0
def test_single_view_is_duplicated_for_world_model(patch_vla_jepa_external_models: None) -> None:
"""With one dataset view and jepa_tubelet_size=2, the view must be duplicated before encoding."""
set_seed_all(42)
policy = VLAJEPAPolicy(_make_multiview_config(num_views=1, jepa_tubelet_size=2))
policy.train()
captured_videos: list = []
original_processor = policy.model.video_processor
class _CapturingProcessor:
def __call__(self, videos: list, return_tensors: str) -> dict:
captured_videos.extend(videos)
return original_processor(videos=videos, return_tensors=return_tensors)
policy.model.video_processor = _CapturingProcessor()
policy.forward(_make_multiview_train_batch(num_views=1))
# reshape is batch-major: (b0v0, b0v1, b1v0, b1v1, …)
assert len(captured_videos) == BATCH_SIZE * 2
for i in range(BATCH_SIZE):
np.testing.assert_array_equal(captured_videos[2 * i], captured_videos[2 * i + 1])
def test_excess_views_trimmed_for_world_model(patch_vla_jepa_external_models: None) -> None:
"""With three dataset views and jepa_tubelet_size=2, only the first two views reach the encoder."""
set_seed_all(42)
policy = VLAJEPAPolicy(_make_multiview_config(num_views=3, jepa_tubelet_size=2))
policy.train()
captured_videos: list = []
original_processor = policy.model.video_processor
class _CapturingProcessor:
def __call__(self, videos: list, return_tensors: str) -> dict:
captured_videos.extend(videos)
return original_processor(videos=videos, return_tensors=return_tensors)
policy.model.video_processor = _CapturingProcessor()
policy.forward(_make_multiview_train_batch(num_views=3))
# Only B*2 items must reach the encoder, not B*3.
assert len(captured_videos) == BATCH_SIZE * 2