--- license: cc0-1.0 pretty_name: Dancing Chibi Figures language: - en task_categories: - text-to-video - text-to-image - image-to-video - keypoint-detection - image-segmentation tags: - synthetic - video-diffusion - motion - chibi - character-animation - sprite - benchmark - toy-dataset size_categories: - 100K

*One row per motion group; every clip also carries depth, camera-space normals, part segmentation and joints:*

The stick-figure dataset was the minimal case (lines, an exact oracle). This is the next rung: a **real character with volume** — a grey, flat-shaded chibi mannequin (~2.8 heads tall, face guide cross, dark outline, the kind of template figure drawing books use) — while every pixel is still a deterministic function of ~30 known parameters. Same motion, same cameras, same `clip_id` as the stick-figure dataset, so the two can be used together (skeleton → character, stick render ↔ chibi render, pose estimation on chibi proportions). > **v0.1 = first public cut.** Rendering, labels and splits are final for this version. Captions are templated from the > motion labels (see *Captions*) and may be refined in v0.2 without re-rendering. ## Which config? | config | rows | size | contents | |---|---|---|---| | `frames` (default) | 514,800 frames | 5.1 GB | 128² RGBA colour (WebP lossless) + depth16 + normals + seg + all labels + captions | | `mini` | 514,800 frames | 2.09 GB | **64²** version of `frames` — laptops, Colab, classrooms | | motion | — | — | the raw ARDY motion is identical to the stick dataset's `motion` config (same `clip_id`); the chibi retarget is `generator/chibi.py` in the code repo | ## Quick start ```python from datasets import load_dataset ds = load_dataset("sprited/dancing-chibi-figures", "frames", split="validation") row = ds[0] row["color"] # PIL RGBA image, transparent background row["caption"] # "Seen from the front-right, a chibi mannequin waves hello with the right hand; it raises the right hand to head level at 0.5 s ..." row["caption_dynamic"] # observed motion only (from the labels, never from the prompt) row["prompt"] # the text the motion was generated from: "A person waves hello with the right hand." import json, numpy as np events = json.loads(row["events"]) # per-clip motion events (same on every row of a clip) xy = np.frombuffer(row["joint_xy"], np.float32).reshape(27, 2) # normalised [0,1] image coords seg = np.array(row["seg"]) # bone id per pixel (0 = background) ``` Composite the RGBA colour over any background you like; depth/normal/seg let you relight or recolour it (the render is unlit on purpose — the normals are there so you can "afterlight" it). ## What is in a frame **`frames` / `mini` — one row per rendered frame.** | column | type | meaning | |---|---|---| | `sample_id`, `clip_id`, `frame_idx`, `n_frames`, `fps` | str/int | `clip_id = group/prompt_slug_s{seed}/c{cam}`; 120 frames per clip, 20 fps; **identical ids to Dancing Stick Figures** | | `split`, `group`, `held_out` | str/bool | split ∈ train/val/test; group ∈ dance, gesture, locomotion, transitions, idle, acrobatic, **sport** (held out → test only) | | `prompt` (= `text`) | str | the ARDY motion prompt the clip was generated from (143 unique) — the *intent*, not a description of the clip | | `events` | JSON str (identical on every row of a clip-camera) | rule-based motion events from the labels: `travel_m`, `travel_dir`, `heading_change_deg`, `jumps` [[t,dur]], `steps`, `left/right_hand_above_head / _raised / _forward`, `left/right_foot_raised`, `low_posture`, `lying`, `inverted`, `hips_height_m`, `activity_per_s`, `active_s` | | `caption_static` | str | appearance + framing + camera (constant over the clip) | | `caption_dynamic` | str | the observed motion in temporal order, generated from `events` only | | `caption_short`, `caption`, `caption_dense` | str | 5–10 words / 1–2 sentences / 3–6 sentences; 2–3 paraphrase templates sampled per clip-camera | | `seed` | int | ARDY seed 0–9 | | `qa_flags` | str | comma list; `prompt_mismatch:no_locomotion / no_jump / no_turn / no_low_posture / no_arms_up` (heuristics: the clip contradicts its prompt), `frozen`, `out_of_frame` (a joint centre leaves the image — 0.31 % of frames, almost all in `transitions` clips that start on the floor and stand up; the fixed camera is framed on the frame-0 hips). Kept, not filtered | | `cam_yaw`, `cam_pitch` | float (rad) | orthographic camera, same sampling and values as the stick dataset; yaw 0 = figure faces the camera; **positive pitch = camera slightly below** the horizontal | | `cam_center_x/y`, `px_per_m` | float | projection in 128-px units: `x_px = cx + px_per_m·x` (for `mini` divide by 2); scale 50–58 px/m | | `joint_xyz` | binary f32[27,3] | figure-frame 3D joints (x left, y up, z forward), metres, Hips at frame 0 = origin | | `joint_xy` | binary f32[27,2] | image coordinates, normalised to [0,1] | | `joint_depth` | binary f32[27] | depth toward the camera (m), Hips-relative, same convention as the depth map | | `joint_visible` | binary u8[27] | **1 if the bone owns ≥1 pixel in `seg`** — NOT the stick dataset's per-joint occlusion test, despite the same column name; hand-tip and toe bones are absorbed by their neighbours in `seg` and are always 0 (use `joint_xy` for an in-frame test). Will be unified with the stick semantics in v0.2 | | `root_pos`, `root_vel`, `root_heading` | binary f32[3], f32[3], f32[2] | Hips trajectory in the frame-0 figure frame (world travel — the render itself is hips-centred); heading = (cos, sin) yaw | | `foot_contacts` | binary u8[4] | ARDY foot contacts: LeftFoot, LeftToe, RightFoot, RightToe | | `color` | image | 128×128 RGBA WebP (lossless), **transparent background**, unlit flat grey | | `depth` | image | 16-bit PNG, `depth = lo + u16/65535·(hi−lo)`, range [−1.5, 1.5] m toward the camera around the Hips, 0 = background | | `normal` | image | RGB WebP (lossless), camera-space normal `n = rgb/255·2−1` (x right, y up, z toward camera) | | `seg` | image | 8-bit PNG, value = joint id + 1 of the bone owning the pixel (0 = background); exact at render resolution, majority-vote downsampled | | `config`, `size` | str/int | `frames`/128, `mini`/64 | **All left/right in prompts, captions, events and joint names are the figure's own left/right (egocentric), not the viewer's** — a figure facing the camera points "to the left" toward screen-right. Binary columns are raw little-endian arrays: `np.frombuffer(row[col], dtype).reshape(shape)`. Skeleton (`cskel27`, index order): Hips, Spine, Spine1, Spine2, Spine3, Neck, Head, RightShoulder, RightArm, RightForeArm, RightHand, RightHandEnd, RightHandThumb1, LeftShoulder, LeftArm, LeftForeArm, LeftHand, LeftHandEnd, LeftHandThumb1, RightUpLeg, RightLeg, RightFoot, RightToeBase, LeftUpLeg, LeftLeg, LeftFoot, LeftToeBase. `Head` is the head-sphere **centre** (skull base in the stick dataset). ## Captions: prompt ≠ caption The ARDY prompt is what we *asked for*; the clip is what the motion model *produced*, and they disagree more often than you would think ("walks in a circle" turns 62°; "does jumping jacks" jumps twice, then stands). So the captions are generated **from the labels**, Seedance-style: a static part (appearance, framing, camera), a dynamic part (events in temporal order), and three granularities, with the prompt kept as a separate `prompt` column and a `prompt_mismatch` flag when the two clearly contradict. The render is hips-centred, so the captions say "the camera follows the hips" and never claim visible travel; travel lives in `events` / `root_pos`. We also ran an off-the-shelf video VLM (Qwen3-VL-8B) on the clips: it described ~half of them correctly (sitting, waving, kicking) and missed whole-body fast motion (jumps, a flip) and turning on this featureless mannequin — a useful probe, not a caption source; VLM captions are not included in v0.1. ## Splits By **prompt**, never by seed or camera (identical to the stick dataset): `sport` is held out entirely; else hash(prompt) → 90/5/5. | | frames | |---|---| | train | 363,600 | | validation | 18,000 | | test (incl. sport) | 133,200 | ## How it was made prompt → **NVIDIA ARDY** text-to-motion (6 s, 20 fps, seeds 0–9; the same clips as the stick dataset) → chibi retarget (same joint rotations on chibi bone lengths; root travel scaled by the leg ratio so the feet do not slide; ground from foot contacts) → **Blender 5.1** procedural rig (Skin-modifier mannequin over the 27-joint graph + sphere head, heat weights, dual-quaternion skinning; flat Emission material, inverted-hull outline, face guide cross) → 3 orthographic cameras per clip (same sampling as the stick dataset) → two headless Eevee passes per frame (anti-aliased colour; 1-sample exact depth / normal / segmentation) at 256², box-downsampled to 128 / 64 → parquet. Deterministic from `clip_id`; the generator is in the code repo. ## Intended use / limitations Teaching and benchmarking small video/image generative models, conditional generation (skeleton/seg/depth → character), pose estimation on chibi proportions, sprite/character animation research. One template character only (no clothes, hair, faces, props); hips-centred framing (no visible travel); ~0.3 % of frames are partly out of frame (flagged `out_of_frame`); the rig mesh has small internal defects at the neck and wrists invisible at ≤256 px; `prompt_mismatch` flags are heuristics; camera pitch sign follows the stick dataset (positive = from slightly below). ## Baselines & tutorial Two tracks, both trained on `mini` (64px): **🤗 diffusers-standard** — load with three lines, everything transfers to any diffusers project: - [sprited/dancing-chibi-figures-ddpm-64](https://huggingface.co/sprited/dancing-chibi-figures-ddpm-64) — unconditional `DDPMPipeline` (UNet2DModel, 4-channel RGBA). - [sprited/dancing-chibi-figures-t2i-64](https://huggingface.co/sprited/dancing-chibi-figures-t2i-64) — **text-to-image**: a miniature Stable Diffusion (UNet2DConditionModel + frozen CLIP + classifier-free guidance, no VAE). ```python from diffusers import DiffusionPipeline pipe = DiffusionPipeline.from_pretrained("sprited/dancing-chibi-figures-t2i-64", custom_pipeline="sprited/dancing-chibi-figures-t2i-64", trust_remote_code=True) imgs = pipe(["a person jumps in place"] * 4, num_inference_steps=50, guidance_scale=3.0).images ``` **pure PyTorch** — [sprited/dancing-chibi-figures-baselines](https://huggingface.co/sprited/dancing-chibi-figures-baselines): a 64px image model and a **text-conditioned autoregressive video** model (chunked diffusion, CLIP prompt embeddings); trainer and `scripts/rollout.py` in the code repo. A ComfyUI node (`comfy/qversion-chibi`) wraps the image checkpoints. **📓 Colab tutorial** — [dancing_chibi_figures_colab.ipynb](https://github.com/sprited-ai/dancing-chibi-figures/blob/main/notebooks/dancing_chibi_figures_colab.ipynb): look at the data, train the text-to-image model from scratch, turn it into a video model, grade it with a counting robot — free-T4-sized, written for absolute beginners. (Sequel to the stick-figures notebook.) ## Versioning v0.1 (2026-08) first public cut. Planned v0.2: more prompts (a curated set of ~300 from a chibi pose reference book), an anatomy oracle, post-processed outlines, optional colour-coded config, 8-direction sprite views. ## License and attribution Data CC0-1.0. Motion generated with NVIDIA ARDY (NVIDIA Open Model License, which claims no ownership of outputs); character, rig and renderer are procedural code (MIT) — no third-party 3D assets. Paired dataset: [sprited/dancing-stick-figures](https://huggingface.co/datasets/sprited/dancing-stick-figures).