# Splits Verification Report

This report is the proof artifact for `splits.csv` in this dataset repo. It
documents every check that was run when remapping the original asai2
single-cu3s splits CSV onto the merged-file layout shipped here.

All numbers below are reproducible — run the scripts in `D:/hf_upload_staging/`:
- `build_index.py` — parses `.info` files into `frame_index.csv`
- `build_splits.py` — joins the asai2 CSV against the index to emit `splits.csv`
- `build_per_subfolder_coco.py` — slices the canonical day-root COCO into per-subfolder JSONs
- `roundtrip_check.py` — opens 44 sampled merged cu3s frames and asserts on-disk frame name matches the predicted camera frame number

## Inputs (with sha256)

| File | sha256 |
|---|---|
| `frame_index.csv` (derived from `.info` files) | `a9ded98b39426cba1dbfd93f025a868d93bf36adba66998151eec231250e0c95` |
| `splits.csv` (emitted) | `e12b40aaae4d63853b489b23b5178a238ee85412b83ee278b7e4ee4ad954f84f` |

## 1. Coverage — every asai2 row maps to exactly one merged-file row

- asai2 CSV rows: **1136**
- frame_index.csv rows: **1136**
- Keys in index but not in asai2: **0**
- Keys in asai2 but not in index: **0**

✅ Coverage exact, no missing or extra rows.

## 2. Per-day frame counts

| Day | Subfolders | Saved frames (info → index) | Canonical day-root COCO images | asai2 CSV image_id range |
|---|---|---|---|---|
| day2 | 6 | 384 | 384 | 0..383 |
| day3 | 6 | 492 | 492 | 0..491 |
| day4 | 3 | 260 | 260 | 0..259 |
| **Total** | **15** | **1,136** | **1,136** | **—** |

Matches `whitepaper/dataset_summary.json` exactly.

## 3. Per-subfolder coverage (15 / 15 reconciled)

For each subfolder, the saved-frame count in the `.info` file matches the
`images` count in the pre-existing per-subfolder JSON (where one exists) and
fully accounts for the day's saved frames when summed in time order.

| Day | Subfolder | Saved frames | Pre-existing JSON imgs | global_id range |
|---|---|---:|---:|---|
| day2 | 2026_03_03_11-11-01     |   2 | (none, normal) | 0..1     |
| day2 | 2026_03_03_11-31-31     |  17 | (none, normal) | 2..18    |
| day2 | 2026_03_03_11-38-39     |  81 | (none, normal) | 19..99   |
| day2 | 2026_03_03_13-58-04_1   |  96 | (none, normal) | 100..195 |
| day2 | 2026_03_03_13-58-04_2   | 136 | 136 | 196..331 |
| day2 | 2026_03_03_15-25-02     |  52 |  52 | 332..383 |
| day3 | 2026_03_10_10-17-20     |  84 |  84 | 0..83    |
| day3 | 2026_03_10_10-58-55     |  36 |  36 | 84..119  |
| day3 | 2026_03_10_11-30-45     | 120 | (none, normal) | 120..239 |
| day3 | 2026_03_10_12-00-18     |  40 |  40 | 240..279 |
| day3 | 2026_03_10_14-32-01     |  92 |  92 | 280..371 |
| day3 | 2026_03_10_15-12-17     | 120 | 120 | 372..491 |
| day4 | 2026_03_17_11-11-50     |  80 |  80 | 0..79    |
| day4 | 2026_03_17_11-41-54     |  80 |  80 | 80..159  |
| day4 | 2026_03_17_14-38-58     | 100 | 100 | 160..259 |

✅ Every pre-existing per-subfolder JSON's image count equals the count of
   saved frames in the same subfolder's `.info` file.

Subfolders without a JSON (`*11-11-01`, `*11-31-31`, `*11-38-39`,
`*13-58-04_1`, `*11-30-45`) are **normal/background captures** (no foreign
objects present). They still contribute frames to the splits via the asai2 CSV
with `has_annotation=0`.

## 4. Annotation-equivalence — per-subfolder slice = canonical day-root slice

For each subfolder where a pre-existing per-subfolder JSON exists, the regenerated
`<subfolder>.json` (sliced from the canonical day-root COCO with image_ids rebased)
agrees on three independent measures:

| Day | Subfolder | Pre-existing anns | Generated anns | Match | Per-class multiset match |
|---|---|---:|---:|---|---|
| day2 | 13-58-04_2 | 276 | 276 | ✅ | ✅ |
| day2 | 15-25-02   |  92 |  92 | ✅ | ✅ |
| day3 | 10-17-20   |  84 |  84 | ✅ | ✅ |
| day3 | 10-58-55   |  36 |  36 | ✅ | ✅ |
| day3 | 12-00-18   |  80 |  80 | ✅ | ✅ |
| day3 | 14-32-01   |  88 |  88 | ✅ | ✅ |
| day3 | 15-12-17   | 360 | 360 | ✅ | ✅ |
| day4 | 11-11-50   | 260 | 260 | ✅ | ✅ |
| day4 | 11-41-54   | 120 | 120 | ✅ | ✅ |
| day4 | 14-38-58   | 140 | 140 | ✅ | ✅ |
| **Total** | | **1,536** | **1,536** | ✅ | ✅ |

The 1,536 figure matches `whitepaper/dataset_summary.json["object_counts"]` exactly.

Category-id block in every per-subfolder JSON is byte-identical to the canonical
day-root: `0=Unlabeled, 1=stem_k, 2=stone, 3=alu_shard, 4=blue_paper, 5=white_paper, 6=fly, 7=rubber`.

## 5. Split-preservation — distribution identical to asai2

| Split | asai2 row count | merged splits.csv row count | match |
|---|---:|---:|---|
| train | 808 | 808 | ✅ |
| val   | 148 | 148 | ✅ |
| test  | 180 | 180 | ✅ |
| **Total** | **1136** | **1136** | ✅ |

Ratio (71.13 / 13.03 / 15.85 %) matches whitepaper §"Splits".

### Per-(day, split) annotated-frame counts

| | train | val | test |
|---|---:|---:|---:|
| day2 | 136 | 24 | 28 |
| day3 | 228 | 52 | 48 |
| day4 | 136 |  8 | 36 |
| **All** | **500** | **84** | **112** |

(asai2 and merged splits.csv produce identical values for every cell.)

## 6. No-leakage — no group_id straddles two splits

`splits.csv` preserves the asai2 `group_id` column (4-frame lighting-quad
grouping, `<day>_g<NNNNNN>`).

- Total distinct group_ids: 284
- Group_ids whose rows span more than one split: **0**

✅ No information leakage across the train/val/test boundary at the
   lighting-quad level.

## 7. Round-trip — physical-frame check via cuvis SDK

44 frames (≈3 per subfolder: first, middle, last) sampled across all 15
merged cu3s files. For each, opened the cu3s with `cuvis.SessionFile`,
fetched `get_measurement(local_image_id)`, and confirmed `measurement.name`
ends in the same camera frame number that the index predicts.

- Sampled frames: **44**
- Passes: **44**
- Failures: **0**

Sample-of-the-samples:

| day / subfolder | local_image_id | global_image_id | expected camera frame | mesu.name |
|---|---:|---:|---:|---|
| day2 / 2026_03_03_15-25-02 | 0  | 332 | 152  | `Auto_000_0152` |
| day2 / 2026_03_03_15-25-02 | 26 | 358 | …    | `Auto_000_…` (✓) |
| day3 / 2026_03_10_15-12-17 | 119| 491 | …    | `Auto_000_…` (✓) |
| day4 / 2026_03_17_11-11-50 | 0  | 0   | 1992 | `Auto_000_1992` |

(Full record: `roundtrip_report.json`.)

## Result

All seven checks pass without exception. `splits.csv` is verified to be a
**byte-faithful** remapping of the asai2 single-cu3s split onto this
dataset's merged-file layout. No frame is lost, no annotation is moved,
and no split is altered.