glory-hyeok/robocurate-synth100

synth100 — 100 generated clips for validating Pre-Contact Level Filtering

100 episodes drawn (seed 20260824) from the 952-episode multi-object generation set, packaged so Stage-5 filtering can be run on them without re-deriving anything. Every input the filter needs travels with the package, in the space it is consumed in.

Read section 1 before using this. The single most important fact about this data is not in the file layout, and getting it wrong invalidates any score computed from it.

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0. Attribution and license

Part of this package is a third-party dataset. Read this before using it.

Upstream capture	FourierIntelligence/ActionNet (Fourier Intelligence). Robot: Fourier GR1-T1, 6-DoF Fourier DexHands, one head-mounted camera
ActionNet-derived, redistributed here	conditioning/, conditioning_undist/, real_video/ (real frames and episodes), gtdepth/ (the release's own sensor depth, undistorted and downsampled), s0.npz, and the prompt_actionnet_real / task_actionnet columns
Upstream terms govern that payload	Whatever the upstream repository states. If they disallow redistribution, tell us and this comes down.
Ours (CC-BY-4.0)	generated/ (our I2V generators' output), actions/ (IDM read-out), instruction_generated/, all four mask resolutions, pre_*/, pre2_*/, occ_*/, sphere/, gallery2/, manifest.csv, camera.json, and this document

A fuller treatment of the capture itself -- what the depth is, the two-clock alignment bug, the fisheye-vs-pinhole mask warning -- is in the companion card, glory-hyeok/actionnet-subset100-gtdepth. That card is the reference for the capture; this one is about what we generated from it.

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1. The instruction is counterfactual — this is not a reproduction task

The generator was not asked to reproduce the source episode. It was given the episode's real first frame and told to fetch a different object:

what the real video shows	"Pick up the donut and put it on the third shelf"
what the generator was told	"…pick up the target plastic cup and put it in the plastic basket"

91 of the 100 name a target the real episode never touches. Three consequences, all of which change how a number computed here should be read:

1. Judge against instruction_generated/, never against prompt_actionnet_real. The latter is provenance only — it says which episode the conditioning frame came from.
2. real_video/ is not ground truth. Its arm goes to a different object. It is not an upper bound on anything.
3. real_video/ is therefore a negative control, and a good one: same scene, same conditioning frame, an arm that genuinely moves and grasps — just not the instructed object. Harder than the idle-hand control used on the real set, which never moves at all.

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2. Layout

manifest.csv                 ulid · instruction_generated · target_object · destination ·
                             prompt_actionnet_real · task_actionnet · s0_source · n_action
s0.npz                       ulids (100) + s0 (100, 44)          the robot at the conditioning frame
camera.json                  K_pinhole · K_fisheye · D · space definition

conditioning/<U>.png         real conditioning frame, 1280x800, FISHEYE, lossless
conditioning_undist/<U>.png  the same frame, 1280x800, UNDISTORTED PINHOLE   <- estimate depth here
real_video/<U>.mp4           the full real episode, 1280x800 fisheye, 30 fps  (negative control)

mask/<U>_{target,source}.png       1280x800 FISHEYE      as delivered
mask_undist/<U>_{target,source}.png 1280x800 PINHOLE     for the 3-D lift
mask_768/<U>_{target,source}.png    768x432              for occlusion on the generated clip

generated/{mot,diffonly,block18}/<U>.mp4   768x432, 16 fps, 93 frames
actions/{mot,diffonly,block18}/<U>.npz     action (93,44) + timestamp, from the IDM

gtdepth/depth_<U>.npz        GROUND-TRUTH depth at the conditioning frame, from the sensor:
                             depth (1,400,640) float32 metres, ds=2, K_ds, frame_indices
instruction_generated/<U>.txt  the counterfactual instruction, verbatim, one per clip

pre_{mot,diffonly,block18}/pre_<U>.json    Pre-Contact result: entry frame, sphere centre and
                                           radius, per-frame tip_{L,R}_cm
occ_{mot,diffonly,block18}/occ_<method>_0.json   Occlusion result: peak over the +-1 s window
sphere/<method>_<U>_web.mp4      Pre-Contact video   (10 sampled clips)
gallery2/<method>_<U>_web.mp4    Occlusion video     (the same 10)

gtdepth/ is the sensor's own depth, extracted from the public ActionNet release with synth_gtdepth_npz.py through the SAME undistort maps as the masks. It is here so a depth model can be scored against it -- at inference the filter is meant to run on a predicted map from conditioning_undist/ alone. All 100 verified: object-region validity median 100 %, minimum 61.5 %; object distance 0.46-0.94 m.

target is the object to fetch, source is the acting arm. Both are frame-0 masks.

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3. Three spaces, and which one each thing lives in

space	what is in it	K
fisheye 1280x800	conditioning/, real_video/, mask/	127° equidistant, f 577.47
pinhole 1280x800	conditioning_undist/, mask_undist/, depth belongs here	[[640,0,639.5],[0,640,399.5]]
768x432	generated/, mask_768/	fx 384, fy 345.6 — see below

Depth must be estimated on conditioning_undist/, not on the fisheye frame. P = D·K⁻¹p with a pinhole K over fisheye pixels bends a flat table into a bowl.

768x432 is an anisotropic resize of the fisheye frame, not a crop. Solved by matching the same frame in both resolutions (correlation 0.997) and confirmed against the generator's own dataloader: F.resize(frame, (432,768), antialias=True). Horizontal scale 0.600, vertical 0.540 — pixels are not square, so do no geometry at 768x432. Occlusion is a ratio of two masks that both went through the same resize, so it is unaffected. mask_768 is produced the way the generator produces it: TF.interpolate(mask/255, (432,768), mode="area") > 0.5, not nearest-neighbour.

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4. The IDM actions: units and sign

actions/ holds what an inverse-dynamics model read out of the generated pixels. Same 44-channel layout as our states (left_arm 0-7, left_hand 7-13, left_leg 13-19, neck 19-22, right_arm 22-29, right_hand 29-35, right_leg 35-41, waist 41-44), and the body channels are radians on both sides. The hand channels are not:

	our 44-D state (s0.npz)	IDM action
units	Fourier raw, 0–10.3	radians
closing	negative in this URDF	positive
the exception	thumb pitch, whose range is reversed	thumb pitch, same sign

Feeding IDM hand values through the Fourier conversion puts the fingers at nonsense angles, and mixing the two in a rollout (q + α(a − q)) is arithmetic across unit systems. Use fk.rollout_from_idm_actions, which brings both into radians first. Confirmed physically: the values start near 0, rise to 0.8–1.7 mid-clip and return — a hand opening, closing on the object, and letting go.

The clip is 16 fps, so a ±1 s window is ±16 frames, not ±30. The rollout coefficient needs no adjustment for that: the same episode rolled at 15 and 16 Hz differs by 0.03°, against the rollout's own 0.46° error.

The acting arm is named in the instruction ("the source right robot arm") — 74 right, 26 left — so it need not be inferred.

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5. Where s₀ came from, and why row 0 is safe

observation.state[0] of the matching LeRobot episode. The ActionNet→LeRobot conversion pairs a 60 Hz robot sample with a 30 fps camera frame, so indexing states by frame number is wrong by up to 9 cm at the moving arm — but not at frame 0, where both conventions coincide. Checked against our own hdf5-resampled states on the 6 episodes present in both sets: body joints agree to 1e-4 rad; only a thumb channel differs, by 2.7 % of its raw range.

5 of the 952 have no recoverable s₀ and were excluded before sampling.

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6. What this data is harder than the real set at

	real 100 (croissants)	here
distinct prompts	3	91
target mask, median	11 844 px	2 414 px
boundary sphere	8.2 cm	6.23 cm measured (≈3.7 cm expected — see §7)
clip	~400 frames @ 30 fps	93 @ 16

The targets are blocks, cubes and cups — 0.45x the croissants in linear size. Any tolerance measured on the real set (depth scale error, rollout offsets) is looser than what is needed here and has to be re-derived. The rollout offsets' largest arm term is 4.29°, about 6 cm at the fingertip, which now exceeds the sphere itself.

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7. Known limitation: the boundary sphere is inflated, and why the real set never showed it

Measured on all 100 with GT depth, the sphere's median radius is 6.23 cm against the ~3.7 cm the objects' size predicts, and 16 of 100 exceed 10 cm -- larger than the croissant sphere on the real set, for objects less than half the size.

Splitting the clips by how far the depth spreads over the target mask shows what is moving:

depth spread (1-99 pct)	clips	x	y	z	sphere
<= 5 cm	14	5.8	5.0	3.2	4.02 cm
5-10 cm	43	6.5	6.2	5.8	5.64 cm
10-15 cm	22	7.5	7.2	8.6	7.21 cm
> 15 cm	21	9.3	6.6	15.2	11.46 cm

Width and height barely move; depth runs 3.2 -> 15.2 cm, a factor of 4.75. One class of object cannot keep its width and quintuple its thickness, so what varies is the measurement, not the object. The clean group's 4.02 cm also lands on the ~3.7 cm predicted independently from object size -- that is the real number.

Why the real set never showed this. The same border leak is present there. Two things hid it:

1. The croissant is large and anisotropic. Its AABB is 13.1 x 7.0 x 7.1 cm -- a genuine 13 cm object, whose longest axis is real and dominates the half-diagonal (depth is 43 % of it). The block is 5.8 x 5.0 x 3.2 -- nearly isotropic, and depth is its shortest true axis, so it has the most room to be corrupted and takes over the diagonal the moment it is. Adding 5 cm of leak to z grows the croissant sphere 24 % and the block sphere 42 %.
2. The scene. Every real episode has n_obj = 1, and the mask is ours -- SAM 3 text prompt, largest component, area band. A leak has only the tablecloth to land on, at nearly the croissant's own depth. Here the scene is multi-object, the masks ship with the clips, and 91 of 100 have two or more connected components. A leak lands on a neighbouring object at a different distance, which is exactly a large jump in z.

The direction is permissive. A bigger sphere is entered earlier, so an entry that should not have counted does. Entry counts from this package are an upper bound on the affected clips.

Fitting the depth band around the median instead of by percentile suppresses the tail (same 100 clips, sphere radius):

z selection	median	> 10 cm	max
5-95 percentile (what produced the numbers here)	6.09 cm	15	26.1 cm
median +- 3 MAD	5.30 cm	10	17.2 cm
median +- 6 cm (fixed band)	5.77 cm	3	13.2 cm
mask eroded 2 px, percentile trim	5.30 cm	11	24.4 cm

The fixed band is a prior on object depth extent rather than a measurement, so it is recorded here and not yet applied -- changing it moves the gate, and the gate is being settled against human labels.

One thing this table already rules out: the stray mask components are not the cause. 91 of the 100 target masks carry more than one connected component (up to 30), which looks like the obvious culprit -- but the extra components are specks, the largest holds 99.8 % of the area at the median, and tracing the far-depth pixels puts 0 % of them in the specks against 73 % on the main blob's rim. Keeping only the largest component moves the median 6.09 -> 5.90 cm and the tail 15 -> 13 clips: worth doing as hygiene, since the real set's masks are built that way, but it is not the fix. The leak is a border-bleed on the object's own blob, and only the depth selection reaches it.

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8. How to apply Pre-Contact filtering to these clips

The criterion is the one applied to real episodes in glory-hyeok/actionnet-subset100-gtdepth, whose card carries the full recipe. Read that first; this section is only the four places the generated set differs, and each of them is a place to get it wrong.

8.1 The action stream is predicted, and its hand channels are not the real set's units

There, the rollout integrates the dataset's recorded actions. Here it integrates what an inverse dynamics model read out of the generated pixels -- which is the whole point: the actions are the only thing the generation can influence, so this half of the filter looks at the generation through them and never at the rendering.

The rollout model is identical (beta = 0, alpha = 0.45 body / 0.60 hand), and so are both offset layers. What is not identical is the hand:

	real set	here
hand channels	DexHand raw, [0, 10.3]	radians, with their own sign
sign	as recorded	[-1, -1, -1, -1, +1, -1] over the 6 slots -- thumb pitch is the one slot that agrees

So the hand cannot go through the same conversion. Feeding the raw mixture subtracts radians from DexHand units, and any clamp written for [0, 10.3] then flattens every closing finger to zero -- silently, with a trajectory that still looks plausible. If you reuse a rollout routine from the real path, check its hand clamp is unit-aware before trusting a single number.

A convention check that needs no unit knowledge: the fingertips should converge at the entry frame. They do, by 2.57 cm in 19 of 20 clips -- the geometric event and the grasp coincide, from two signals that share no code.

8.2 The clock is 16 fps, so +-1 s is +-16 frames

Not 30. actions/<method>/<U>.npz holds 93 actions per clip, the clip holds 93 frames, and rollout[t] corresponds to video frame t (rollout[0] is s0, the conditioning frame). The rollout is one sample longer than the video; that last sample has no pixel and should be ignored.

8.3 Two spaces, and only an integer crosses between them

	space	why
Pre-Contact	1280x800 pinhole (conditioning_undist/, mask_undist/, gtdepth/)	K and the extrinsic are calibrated there, and it is where the object is lifted. No fisheye model, no anisotropic resize.
Occlusion	768x432 (generated/, mask_768/)	the arm mask has to come out of the generated frames, and that is their resolution

The only thing that crosses is the entry frame number. Nothing is unprojected on the Occlusion side, so the anisotropic resize costs nothing there -- the score is a ratio of two masks that both went through it.

Do not score Pre-Contact at 768x432. mask_768 is an anisotropic resize of the fisheye frame (scale_x 0.600, scale_y 0.540 -- pixels are not square), and a pinhole K applied to fisheye pixels bends a flat table into a bowl. If you want to draw the boundary on a clip, project through the fisheye model at 1280x800 first and only then apply the two scales; and draw an ellipse, not a circle -- f*r/z is a pinhole identity, and through this chain it comes out 4 % too wide and 17 % too tall.

8.4 The Occlusion arm mask is seeded from a shipped mask, not from geometry

mask_768/<U>_source.png is the acting arm at frame 0 (_target is the object). Seed the tracker from it -- erode first, so a one-pixel error does not pick the tablecloth -- and track forward from frame 0 through the window. On the real set the seed came from FK points projected out of the state, so this also removes the last place the pixel half leaned on the geometry it is meant to corroborate.

The score and the window are unchanged: max over the +-16 frames of |arm ∩ object_at_frame_0| / |object_at_frame_0|.

8.5 Judge against the generated instruction

instruction_generated/<U>.txt, never prompt_actionnet_real. See §1 -- and note the instruction also names the acting arm ("the source right robot arm"), so the task hand is given rather than inferred from hand-channel closure. All 100 say exactly one of source right (74) / source left (26); if you match on the string, fail loudly rather than defaulting, or a phrasing change measures the idle arm on every clip.

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8.6 The frame-0 rule costs nothing here either

Pre-Contact is an event: the entry frame is the first frame at distance 0 having been outside on the frame before, so frame 0 can never qualify. 21 of 300 clips start inside the sphere -- exactly 7 per method, because all three generators share the same 100 conditioning frames, so frame 0 does not depend on the generator. All 21 get an entry event anyway: the hand leaves and comes back. Nothing is lost to the rule. A clip with no entry is a clip whose fingertip never reached the boundary, which is the signal.

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9. What came out, and which numbers are shipped

Two Pre-Contact runs are here, and they differ only in the boundary construction:

	pre_*/ (shipped as run)	pre2_*/ (leak fix applied)
mask	as delivered	largest connected component
depth selection	5-95 percentile	median +- 6 cm
sphere radius, median	6.23 cm	5.75 cm
entry: mot	30	27
entry: diffonly	26	23
entry: block18	30	25

pre2_* is the better estimate and the reason is in §7: the fix is surgical, moving the 14 clips whose object-region depth already spanned under 5 cm by nothing at all (4.02 -> 4.02 cm, worst individual shift 0.54 cm) while pulling the 21 leaking ones from 11.46 to 5.91 cm. Both are shipped so the difference can be inspected rather than believed.

The correction is not cosmetic: it breaks a tie. On pre_* mot and block18 are level at 30; on pre2_* block18 loses 5 against mot's 3, giving mot 27 > block18 25 > diffonly 23. block18's entries leaned on inflated spheres more than the others'. One clip goes the other way and gains an entry (mot / 01JMC162SR6WQWELES) -- dropping the leaked points moved the sphere's centre onto the object, not just shrank it.

occ_*/ was scored against pre_*/. 28 clips have a different entry frame under the fix, so their window moved and their Occlusion score is stale; a rescore is outstanding. Occlusion numbers in occ_*/ are valid only for the pre_* entries they were computed from.

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10. The second round (2026-08-25): two fixes, and which run to read

Two defects were found by re-auditing the chain, both of which made the filter too permissive. Both are fixed, and both rounds ship so the correction can be inspected rather than believed.

	first round	second round
Pre-Contact	pre_*/	pre2_*/
Occlusion	occ_*/	occ2_*/
tracked arm masks	not kept	masks2_*/
sample videos	—	sphere/, gallery3/
summary	—	gallery_meta2.json, summary2.json

Read pre2_* + occ2_*. pre_* + occ_* are kept because they are what the first numbers were computed from; mixing a pre2 entry frame with an occ score is the one combination that is wrong, because the window moved.

Fix 1 -- the boundary swallowed leaked depth (see §7)

Mask-border bleed put points at a neighbouring object's depth into the object cloud, inflating the sphere. Selecting depth as a band around the object-region median instead of by percentile moved only the clips that were broken: the 14 whose depth already spanned under 5 cm came out unchanged (4.02 -> 4.02 cm, worst individual shift 0.54 cm) while the 21 leaking ones fell 11.46 -> 5.91 cm.

Fix 2 -- the arm mask deleted the hand

The tracker's largest-connected-component step was being applied to the ARM. Its own help says why that is wrong: "for an ARM it is dangerous -- when the hand is visually separated from the forearm the hand blob is the SMALLER one and gets deleted, which is exactly where the mask is needed." The moment of contact is exactly that moment. With --keep-all-blobs, and the area floor lowered from 0.002 to 0.0005 of the frame so a hand seen edge-on is reported rather than dropped:

	before	after
window frames missing a mask	one clip at 60.6 % coverage	0
tracking failures	—	0
masks shrinking below 25 % of their median	not measured	0

occ2_* records a track block per clip (want, got, arm_px_{med,min,max}, shrunk) so a 0 % score can be told apart from a lost track after the fact. Every occ == 0 in occ_* is suspect for this reason; in occ2_* it can be checked.

What the fixes did to the numbers

	first round	second round
entry: mot / block18 / diffonly	30 / 30 / 26	27 / 25 / 23
both levels pass	28 / 26 / 22	25 / 23 / 20
Occlusion median	46.6 / 26.5 / 53.1 %	48.1 / 28.4 / 53.8 %
sphere radius, median	6.23 cm	5.75 cm

The ranking survives (mot > block18 > diffonly) but every count fell: both fixes removed passes rather than adding them. Two clips are worth naming because they show each fix working in opposite directions. mot / 01JKF6K1A0MAHZKWXG passed at 3.64 % and now scores 0.00 % -- that overlap was a leftover blob, not the hand. mot / 01JMCA6QKK5TXTFL2E had a 12.1 cm sphere that swallowed the hand at frame 0; the corrected 3.38 cm sphere leaves the fingertip 2.31 cm short, so a clip that was unscoreable became an honest near miss.

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11. The third round (2026-08-25): the run to read is pre4

Two more defects were found and closed; pre4_*/ is the final Pre-Contact run and carries the full config stamp per record (mask_lcc, z_band_m, freeze_platform, right_arm_fit_applied).

Fix 3 -- the right arm's zero is session-dependent. At s0, projected fingertips land ON the frame-0 arm mask for left-handed clips (0-12 px) and miss by 22-59 px (~4-10 cm) for right-handed ones, worst on the 01JK sessions. The croissant-era finding that the right arm needs no offset did not transfer. Per-session 4-joint zeros were fitted on the REAL conditioning frames' arm masks (fit_right_arm.py -> right_arm_fit_by_session.json), held-out validated to 0.1-4.2 px, the two thin sessions pooled (28.0 -> 3.0 px held-out). Coverage: every verdict-relevant arm, 300/300. This correction is structurally always available: the I2V conditioning image is a REAL photo and s0 a real state, so every clip carries its own calibration anchor.

Fix 4 -- the IDM drifts channels whose truth is constant. Recorded platform commands never move (waist action range 0.000 deg; idle-hand travel ~0.3 cm), yet the IDM reads out 2.33 deg of waist_yaw and 15 cm of idle-arm travel -- and the pixels at the IDM-claimed idle-hand destination do not change, proving hallucination. Legs, head, waist and the idle arm are held at s0 through the rollout. Only the waist ever touched the verdict (it swivels the task arm ~2 cm).

	pre2	pre3 (+freeze)	pre4 (+right arm)
mot	27	30	31
block18	25	25	21
diffonly	23	24	17

Side runs, same chain: box boundary 20/14/10 (box-only entries: 0 -- the box nests in the sphere); per-axis trim 5-95 sensitivity 25/14/10. The primary is 1-99 + sphere.

Sign-off audit on pre4, all passing: invariants 300/300; sphere bit-identical across the three methods per ULID (it depends only on s0+depth+mask); round-trip reprojection 99/100 in-mask under both camera models; fingertips converge at entry in 94 % of entries (a signal sharing no code with the geometry); a rerun is verdict-identical; an unknown session key announces itself instead of passing uncorrected. Pose-transfer check: at the ENTRY pose the fingertips sit median 1.6 cm (p90 ~5 cm) from the SAM3-tracked arm -- the tail is what Occlusion exists to arbitrate.

occ_*/ and occ2_*/ predate pre4's entry frames and are stale relative to it; the Occlusion realignment is deliberately deferred.

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12. The fourth round (2026-08-25): pre5 is the final run

Two changes, both in the direction the user's scrutiny pushed: symmetry and fewer hidden priors.

Left arm, same treatment. The croissant-era left offset also drifts by session (01JMC: 27.8 px ~ 4.9 cm). Per-session deltas fitted on the same I anchors (fit_left_arm.py -> left_arm_fit_by_session.json), same held-out gate. 01JMC's fit lands at 11.4 px with two parameters at the bound -- adopted, flagged as strained.

z-selection goes hybrid. The fixed band's thickness prior is replaced as sole guard by an intersection of two weak physical statements: a GAP CLUSTER (sort the mask pixels' depths, cut at jumps > 2 cm that one continuous surface cannot produce, keep the median's cluster -- no thickness prior) and the +-6 cm band (continuous table bleed, which has no gap). Measured: the known leak exhibit 10.8 -> 4.2 cm (true cube size recovered), the genuine 24 cm eggplant untouched, >10 cm tail 3 -> 2, clean-clip spheres move toward the size-predicted truth. Alternatives measured and rejected: per-axis 1-99 alone (tail 22, max 70 cm), 5-95 (mitigates only), gap alone (g=1 cuts the real eggplant, g=3 misses the leak), and a support-plane-removal variant with NO thickness prior (loses 4-0 on exhibits: thin objects live near the plane, 9 clips collapse below the pixel floor). Every selector carries one object-scale statement; the band's is explicit and gate-checked per dataset (§13).

	pre2	pre3	pre4	pre5 (final)
mot	27	30	31	28
block18	25	25	21	20
diffonly	23	24	17	17
sphere median	5.75	5.75	5.75	4.95 cm

The tightened boundary removed 4 entries and added none (the hybrid keep-set is a subset of the band's). Sign-off audit on pre5, 6/6: invariants 300/300, sphere bit-identical across methods, round-trip 99/98 of 100 in-mask, fingertip convergence 94 %, rerun verdict-identical, unknown session keys loud.

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13. The fifth round (2026-08-25): pre6 removes the last inherited constant

The left arm had been riding the croissant-era offset as its base -- calibration borrowed from a DIFFERENT dataset, which is exactly what a batch-portable method must not do. Refitting the left arm FROM ZERO on this batch's own I anchors (bound widened to 16 deg): three session groups reach 0.4 / 3.8 / 6.8 px held-out; 01JMC fails the gate at any bound (all parameters pinned -- something beyond a 4-joint zero) and ships UNCORRECTED rather than patched with a borrowed constant. Its margin audit: all 18 of its left-hand verdicts are no-entry with margins beyond the ~3 cm uncertainty, one borderline (diffonly / 01JMC162SR6WQWELES, miss 3.04 cm vs ~2.9 cm uncertainty), flagged here.

The chain now carries NOTHING a new batch cannot re-derive from itself. pre6_*/ is the final run:

	mot	block18	diffonly
entries (n=100 each)	28	20	16

versus pre5 the only change is one borderline diffonly entry (left offset shifted a few mm). Sign-off audit re-run on pre6: see the audit block in SS12 -- all six checks hold.

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14. The sixth round: pre7, and the batch-portability guarantee

The band's last dataset-specific number is gone. +-6 cm becomes +- 0.4 * L_max, where L_max is the clip's own lateral extent (mask angular size x median depth) -- a dimensionless SHAPE statement ("depth extent <= 0.8x max lateral extent") instead of a centimetre constant. Half-widths now self-scale 1.1-10.4 cm across this batch (median 2.8) where the fixed band was always 6.0. On this set it ties the fixed band on every exhibit (leak 4.25 cm, eggplant 13.22, chopsticks 5.52 -- equal to two decimals) and is tighter at the median (4.61 vs 4.91 cm).

Final verdicts (pre7_*/): mot 26 · block18 18 · diffonly 14; sphere median 4.71 cm. The ranking held through all six rounds and every fix moved counts DOWN, never up.

How much the z-selection matters: removing it entirely (sensor gate + per-axis 1-99 only) inflates entries to 37 / 26 / 18 and the sphere to median 7.14 cm, max 70.8. It is not a tweak -- it decides ~40 % of the verdicts.

Running this on a new batch. Every script takes SYNTH_BATCH:

SYNTH_BATCH=/path/to/new_batch python onboard_batch.py       # 7 gates; fits both arms' zeros
SYNTH_BATCH=/path/to/new_batch python synth_precontact.py --method M -o out/
SYNTH_BATCH=/path/to/new_batch python final_audit.py         # 6/6 = the batch's certificate

onboard_batch.py re-derives or re-checks every constant from the batch itself and prints a prescription on failure rather than defaulting: instruction->hand exact partition; platform-static (measured, not assumed -- a moving camera means DON'T freeze); sensor rails auto-derived from the depth histogram; both arms' session zeros fitted from THIS batch's I anchors with a held-out gate (failing sessions ship uncorrected with a margin audit, never patched with a borrowed constant); the band's bite (does it delete what the cluster kept? deep bites mean it is cutting object); IDM hand convention via the convention-free convergence test. On this batch: 7/7, and the sign-off audit 6/6.

One gate was itself wrong and got fixed here: #5 first compared the gap-cluster's WIDTH to L_max and read 1.75, apparently failing -- but the cluster still contains continuous bleed, so its width overstates thickness (leak-resistant core thickness is 0.49). The operational form -- how much of the cluster does the band delete -- reads median 0 %, and deep bites on 4/100.

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15. Porting this method to a NEW synthetic dataset

Nothing in the method is tied to this set. What IS tied to a dataset is a short list of fitted constants -- and every one of them ships with the procedure that fitted it and the gate that accepted it, so onboarding a new set is running a battery, not redoing research. The structural guarantee that makes this work: an I2V clip always carries its own calibration anchor (the conditioning image is a real photo, s0 a real state), so the geometry can always be re-zeroed on the new data itself.

What a new set must provide (the contract): conditioning image I (real) · s0 at that instant · the action stream · a target-object mask at frame 0 (or a real image SAM can mask) · depth at frame 0 (sensor or predicted) · a rule mapping instruction -> task hand · the generator's resize transform (ours: anisotropic 0.600/0.540, no crop).

What gets re-fitted or re-checked on arrival, with what:

constant	nature	procedure	acceptance gate
arm zeros, per session	drifts between capture sessions (proven here: right 4-10 cm)	fit_right_arm.py / fit_left_arm.py on the I anchors	held-out half <= 12 px; unknown session keys announce themselves
platform + idle-arm freeze	valid only if the capture platform is static	measure recorded action ranges (here: waist 0.000 deg) and clip background motion	if the platform actually moves, do NOT freeze -- the assumption is checked, not assumed
rollout beta/alpha	controller-specific	validate_fk_gr1t1.py recipe on held-out real episodes	reproduce recorded states
sensor gate (0.05-2.6 m)	this sensor's zero-marker and saturation rail	histogram the raw depth: invalid marker + the p99==max rail	gate sits inside the rails
z-band 6 cm	thickness prior	object-region depth-spread distribution on the new set	p95 of genuine spread well under 2x band
gap 2 cm	surface-continuity scale	sweep 1/2/3 cm on known-genuine long objects	genuine objects survive, known leaks cut
IDM hand units/sign	IDM-specific	convention-free check: fingertips must CONVERGE at entry	>= 80 % of entries
instruction -> hand	generation-pipeline phrasing	exact-partition check	ambiguity halts, never defaults

What needs no refit: the boundary construction (LCC x sensor gate x hybrid z-select x 1-99 box -> circumscribed sphere), the entry-event rule, the two-space split, and the audit battery itself (final_audit.py: invariants, cross-method structure identity, round-trip reprojection, grasp convergence, determinism, unknown-session alarm). Run the battery; if all six pass on the new set, the port is done.

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16. Provenance

Generated clips and masks: multiobj_final / multiobj_eval (minyoung). block18 there is byte-identical to ckpt18 in the eval tree — the same generator under two folder names, confirmed by hash, so the action files pair as block18 ↔ ckpt18_unified.data_idm.

Every ingredient was verified before packaging: 62 checks across two passes over manifest, s₀, actions, four mask resolutions, videos, conditioning frames, camera and instructions, plus 300 rollout+FK runs across the three generators. No failures.

Method write-up: filtering/docs/stage5-method.md in our internal RoboCurate_V2 repo (not public -- §8 here carries what a reader needs to reimplement).