Domain: Engineering — Agricultural Engineering
Target concept: Comparing the rice grains before and after dehulling, it was verified that the grains were enclosed by the husk prior to dehulling and became oval-shaped, semi-transparent brown rice after dehulling.

Video generation prompt: Place the paddy on a tray for display, then separate the husk from the grains through rubbing or by using a small manual dehuller, and collect the processed grains.

Evaluation guide:
(i) Target concept: Visual verification that paddy rice is husk-enclosed and transforms into oval, semi-transparent brown rice upon dehulling.
Minimum mechanism: Husk must be mechanically separable via rubbing or manual dehuller; separation must yield morphologically and optically distinct kernels with no intermediate or incorrect states (e.g., milled, cracked, or opaque).
(ii)Storyline: Frame 1: Static shot showing paddy rice placed on tray (elongated, opaque, tan-brown husk-covered). Frame 2: Close-up of hands/dehuller contacting paddy with sustained rubbing or cranking motion. Frame 3: Visible separation: husk fragments detaching, grains emerging. Frame 4: Final static shot showing collected grains on same tray (oval, brown, semi-transparent), with husk fragments optionally visible nearby. Perspective: Fixed overhead or 45° front-fixed viewpoint; all key objects must remain fully visible and spatially anchored to tray throughout; no cuts or camera movement allowed: only continuous take.

Manual:
Experimental Procedure
1. Place paddy rice on a flat tray.
2. Rub paddy manually or operate a small manual dehuller to separate husk from grains.
3. Collect the resulting dehulled grains on the same tray.
Observation of Experimental Phenomena
Before dehulling: paddy grains are elongated and fully enclosed by opaque tan-brown husk.
After dehulling: grains are oval-shaped, uniformly brown, and semi-transparent (light passes through edges).
Summary of Experimental Principles
Dehulling removes the outer husk, exposing the brown rice kernel — confirming that paddy is husk-enclosed and that brown rice is naturally oval and semi-transparent.

Prompt Grounding rubric:
level_1: No paddy grains are shown; no tray appears; neither rubbing-by-hand nor a manual dehuller is shown acting on the paddy; and no collected grains are ever shown.
level_2: Only some of paddy-on-tray, the dehulling action, or collected grains appear, and they don't occur in a sensible order, e.g., collected grains are shown before any paddy is placed on the tray, or grains appear with no dehulling action ever shown.
level_3: Paddy is placed on a tray; a hand rubs the paddy or a small manual dehuller is used on it; grains that result from this action are then shown; the tray, the dehulling action, and the resulting grains all appear in this order, though their exact positions relative to one another may drift (e.g., the tray moves out of its original spot, or the grains end up somewhere clearly disconnected from the tray or dehuller).
level_4: Everything required for the 3-point level holds, and in addition, the tray stays in one place throughout, the hand or dehuller visibly contacts the paddy during the dehulling action, and the resulting grains stay on or right next to the tray, with at most one small setup slip, such as the dehuller or hand only being partly visible during contact, or a few stray grains spilling just outside the tray's edge.
level_5: Rubbing by hand or use of a small manual dehuller is shown making direct contact with paddy that sits on the tray; the resulting grains are then visibly collected onto that same tray or an immediately adjacent container; paddy, tray, dehulling implement (hand or dehuller), and grains are all present, correctly identifiable, and appear in the correct place and order with no step skipped or object substituted.

Scientific and Causal Correctness rubric:
level_1: There is no visible change between the paddy and the resulting grains (same shape, same opaque tan-brown color); or the grains shown afterward are white/polished rice, or fully clear/glass-like, rather than brown rice, contradicting how dehulling actually works.
level_2: Grains appear after the dehulling action but keep the husk's opaque tan-brown color and elongated shape, or turn round/spherical, rather than becoming oval-shaped brown rice; there is no visible contrast between the paddy state and the grain state.
level_3: Two visibly distinct grain states appear: the intact paddy (elongated, opaque, tan-brown, fully covered by husk) and the processed grains (oval-shaped, brown, and somewhat see-through at the edges), but the video doesn't make clear that the dehulling action is what turns one into the other (e.g., the two states are never shown in relation to the same dehulling event).
level_4: The intact paddy (elongated, opaque, tan-brown husk) and the processed grains (oval, brown, semi-transparent) both appear with the dehulling action clearly happening between them, so the transformation reads as caused by that action, with at most one small scientific slip, such as the grains looking slightly yellow rather than brown, or no husk fragments appearing even though the husk was removed.
level_5: The paddy starts fully enclosed in opaque tan-brown husk with an elongated shape; the husk is visibly separated from the grain during the dehulling action; the resulting grains are consistently oval-shaped and brown, and light is visibly passing through their edges (showing they are semi-transparent, unlike the opaque husk); separated husk fragments are visibly distinct from the grains, matching how paddy dehulling actually works.

Spatiotemporal Consistency rubric:
level_1: The tray suddenly appears or disappears between shots; the paddy jumps from the hand directly onto the tray with no placing motion; the dehuller or hand jumps to a different position between frames with no motion in between; grains appear on the tray with no visible dehulling action producing them; or the overall brightness of the scene jumps noticeably between shots with no gradual change.
level_2: At least one clear break occurs: a hand holding paddy enters frame and then, in the next shot, the tray is already empty with no placement shown; the rubbing or cranking motion is jerky with gaps (no continuous contact phase visible); or the grains appear collected in a different-looking background or lighting than the dehulling action.
level_3: The tray, paddy, and dehulling implement stay where they were relative to one another throughout each phase (placement, dehulling, collection); the rubbing/cranking motion flows continuously from first contact to separation; the grains appear on the tray as a direct follow-on from the action with no jump cut, though one small flaw may remain, such as the tray shifting slightly between shots with no hand touching it, or the grain pile appearing to jump from empty to full instead of building up gradually.
level_4: Everything required for the 3-point level holds, and in addition, the tray does not move at all once placed; the paddy is set down on it smoothly; the dehulling motion runs unbroken from contact through separation; the grains accumulate gradually in a way that looks physically caused by the ongoing action, with at most one minor flaw, such as a single brief hold in the motion or slight distortion at the very edge of the frame.
level_5: The tray remains completely stationary and fully in view the whole time; the paddy is placed onto it with continuous, unbroken contact between hand, paddy, and tray; the dehulling action shows smooth, uninterrupted motion with consistent scale and perspective; the grains build up on the tray purely as a visible consequence of the dehulling action, with no jump cuts, warping, lighting jumps, or objects shifting position without a visible cause.