Present animation_motion/ as the default set; document the static split

.gitignore

@@ -0,0 +1,4 @@
+.cache/
+__pycache__/
+*.pyc
+.DS_Store

README.md

@@ -28,23 +28,34 @@ configs:
 
 # Mixamo Animations and Characters
 
-A complete snapshot of the [Mixamo](https://www.mixamo.com/) library: **2,446 motion clips** and
+A complete snapshot of the [Mixamo](https://www.mixamo.com/) library: **2,317 motion clips** and
 **114 rigged characters**, exported as binary FBX (FBX 7.7 / `fbx7_2019`) with per-file metadata.
 
 All animations share one uniform 65-joint `mixamorig` skeleton, so any clip can drive any
 compatible character without remapping.
 
+**Use `animation_motion/`.** The full export contains 2,446 files, but 129 of them are single-pose
+assets that carry no motion at all — Mixamo's `*_Pose*` library, plus `T-Pose` and `Leaning`.
+`animation_motion/` is the 2,317 that actually move; `animation/` keeps all 2,446 for anyone who
+wants the poses too. See [Static clips](#static-clips) for how they were separated.
+
 ## Dataset structure
 
 ```
-animation/                  2,446 .fbx   motion only (skeleton + keyframes, no mesh)
+animation_motion/           2,317 .fbx   clips that move  <- use this
+animation/                  2,446 .fbx   the full export, poses included
 character/                    114 .fbx   T-pose characters with skin mesh, as exported
 character_refined/            114 .fbx   same characters, bone namespaces normalised  <- use this
+
+animation_motion_prompts.json            filename -> text label + Mixamo id, 2,317 entries
+animation_motion_frames.json             filename -> keyframe count, 2,317 entries
+static_clips.csv                         the 129 files left out, with the measurement behind it
+
+animation_prompts.json                   the same, over all 2,446
+animation_frames.json                    the same, over all 2,446
+animation_bones.json                     the 65 bone names used by every animation
 metadata.csv                             browsable index of all 2,446 animations
 characters.csv                           browsable index of all 114 characters
-animation_prompts.json                   filename -> text label + Mixamo id
-animation_frames.json                    filename -> keyframe count
-animation_bones.json                     the 65 bone names used by every animation
 characters.json                          filename -> character name + uuid
 character_bones.json                     filename -> that character's bone list
 character_bone_fix_applied.txt           the 27 characters whose bones were renamed
@@ -52,14 +63,42 @@ character_nonstandard_rig.txt            the 4 characters not using `mixamorig:`
 scripts/                                 download, indexing, normalisation and validation code
 ```
 
-Every JSON index is keyed by FBX filename and maps 1:1 onto the files.
+Every JSON index is keyed by FBX filename and maps 1:1 onto the files. The `animation_motion_*`
+pair covers exactly the 2,317 files in `animation_motion/`; the unsuffixed pair covers all 2,446.
+Files in `animation_motion/` are the same bytes as their counterparts in `animation/`.
+
+## Static clips
+
+129 of the 2,446 exported files hold a pose rather than a motion. They are not a download error —
+Mixamo ships a `*_Pose*` library (`Male_Sitting_Pose_12`, `Female_Standing_Pose_14`, …) alongside
+its animations, and those exports are two frames of the same pose.
+
+They were found by decoding every animation curve and measuring its peak-to-peak range, not by
+filename — keyframe count cannot tell them apart, since a static pose still writes a full set of
+keys, and two of them (`T-Pose`, `Leaning`) are not named like poses at all.
+
+`static_clips.csv` lists all 129 with the measurement and the reason:
+
+| reason | count | |
+|---|---|---|
+| `all curves flat` | 122 | every curve identical frame to frame |
+| `float32 rounding noise only` | 6 | peak-to-peak 0.001–0.024, four orders of magnitude below any real clip |
+| `two-frame pose delta, no in-between frames` | 1 | `Female_Sitting_Pose_7`: a real pose change, but only two frames |
+
+The split is unambiguous. The largest static reading is 0.024 and the smallest moving one is 1.115
+(`Sitting_Idle_4`, a 90-frame breathing idle); nothing falls between. Frame counts separate them
+too — every static file has 2 frames, while the shortest real clip has 8.
+
+Quiet clips are **not** filtered: `Idle_5`, `Rifle_Kneel_Idle`, `Sword_And_Shield_Block_Idle` and
+similar read 1–3 peak-to-peak and are kept, because a breathing idle or a held guard is a motion.
 
 ## Tabular index
 
 Two CSVs make the dataset browsable in the dataset viewer and loadable without downloading
 any FBX. They are generated from the JSON indexes by `scripts/build_tables.py`.
 
-`metadata.csv` — one row per animation:
+`metadata.csv` — one row per animation. It covers all 2,446 files; join against
+`static_clips.csv` to restrict it to the ones that move:
 
 | column | meaning |
 |---|---|
@@ -70,6 +109,13 @@ any FBX. They are generated from the JSON indexes by `scripts/build_tables.py`.
 | `frames` | keyframe count |
 | `motion_id` | Mixamo motion UUID |
 
+```python
+import csv
+static = {r["file"] for r in csv.DictReader(open("static_clips.csv"))}
+moving = [r for r in csv.DictReader(open("metadata.csv"))
+          if r["file"].split("/")[-1] not in static]      # 2,317 rows
+```
+
 `characters.csv` — one row per character, with `bone_count` and `covers_animation_rig`
 (`true` for the 97 characters whose skeleton covers all 65 animation bones).
 
@@ -90,20 +136,20 @@ Fetch only the FBX you need:
 
 ```python
 from huggingface_hub import hf_hub_download
-p = hf_hub_download("Linzhan/Mixamo-Animations-Characters", "animation/Jab_Cross.fbx", repo_type="dataset")
+p = hf_hub_download("Linzhan/Mixamo-Animations-Characters", "animation_motion/Jab_Cross.fbx", repo_type="dataset")
 ```
 
 ## Animations
 
-- **Count**: 2,446 clips
+- **Count**: 2,317 clips that move (2,446 including poses)
 - **Format**: binary FBX 7.7, 30 fps, skeleton + animation curves only (no mesh)
 - **Skeleton**: identical 65-joint `mixamorig` rig in *every* clip
-- **Length**: 2 – 1,884 keyframes (mean 121)
+- **Length**: 8 – 1,884 keyframes in `animation_motion/` (2 – 1,884 across the full export)
 
 Files are named after the motion, e.g. `Jab_Cross.fbx`. Distinct motions that share a Mixamo
 name are disambiguated with a numeric suffix (`Waving.fbx`, `Waving_2.fbx`, `Waving_3.fbx`).
 
-### `animation_prompts.json`
+### `animation_motion_prompts.json`
 
 ```json
 "180_Turn_W_Briefcase.fbx": {
@@ -115,7 +161,7 @@ name are disambiguated with a numeric suffix (`Waving.fbx`, `Waving_2.fbx`, `Wav
 
 | field | meaning |
 |---|---|
-| `prompt` | Mixamo's catalogue name. Present for all 2,446 clips. Short (mean 2.6 words), sometimes abbreviated (`W/`, `2hand`, `L`/`R`). |
+| `prompt` | Mixamo's catalogue name. Present for every clip. Short (mean 2.6 words), sometimes abbreviated (`W/`, `2hand`, `L`/`R`). |
 | `description` | Mixamo's longer description. Present for 2,395 clips (97.9%). Fuller natural language (mean 5.0 words) and usually more specific. |
 | `motion_id` | Mixamo's internal motion UUID. |
 
@@ -127,7 +173,7 @@ yields 2,279. Example — `"Angry Gesture"` covers three different motions, sepa
 their descriptions (`Angrily Pumping Fists Forward`, `Seated Idle With Hands On A Table Being
 Rude`, `Angry Forward Gesture`).
 
-### `animation_frames.json`
+### `animation_motion_frames.json`
 
 ```json
 "180_Turn_W_Briefcase.fbx": 68
@@ -195,8 +241,8 @@ names with a different prefix:
 ```python
 import json
 
-prompts = json.load(open("animation_prompts.json"))
-frames  = json.load(open("animation_frames.json"))
+prompts = json.load(open("animation_motion_prompts.json"))
+frames  = json.load(open("animation_motion_frames.json"))
 
 # text label for a motion-conditioned model
 text = {f: (v.get("description") or v["prompt"]) for f, v in prompts.items()}
@@ -210,12 +256,14 @@ Load an animation onto a character in Blender:
 ```python
 import bpy
 bpy.ops.import_scene.fbx(filepath="character_refined/Adam.fbx")
-bpy.ops.import_scene.fbx(filepath="animation/Jab_Cross.fbx")
+bpy.ops.import_scene.fbx(filepath="animation_motion/Jab_Cross.fbx")
 # both armatures now share the `mixamorig:` bone namespace
 ```
 
 ## Known limitations
 
+- **129 of the 2,446 exported files hold a pose, not a motion**, and are excluded from
+  `animation_motion/`. See [Static clips](#static-clips).
 - **51 clips have no `description`** (2.1%). 36 of them have a unique `prompt`, so the
   `description or prompt` fallback is unambiguous. The other 15 share a `prompt` with other
   clips and therefore cannot be told apart from text alone — the worst case is
@@ -233,8 +281,8 @@ animations and `skin=true` for characters, retargeted onto the standard Y Bot sk
 
 Integrity was verified end to end: every FBX parses without truncation, no byte-identical
 duplicates exist, all index keys match the files exactly, every frame count was re-derived from
-the FBX, and all 2,446 motion names/ids plus 114 character names were cross-checked against the
-Mixamo API. The `scripts/` directory reproduces the download, the indexes and all checks.
+the FBX, every animation curve was decoded to separate motion from pose, and all 2,446 motion
+names/ids plus 114 character names were cross-checked against the Mixamo API. The `scripts/` directory reproduces the download, the indexes and all checks.
 
 ## Terms