VALIDATION.md

# Validation Report

## Scope

The current post-v0.3 main-branch candidate validates:

- all 363 canonical Standard rows and direct Standard MP4 paths
- all 128 active Pre-Standard rows and direct Pre-Standard MP4 paths
- persistent record identity and cross-tier uniqueness
- exact Hub Xet file IDs and stored byte sizes
- container-header technical metadata for every active published MP4
- repository membership, filename rules, field types, numeric ranges, and
  stored-orientation consistency

One 6,587,685,497-byte provenance object is promoted to the canonical root,
and the distinct 496,296,535-byte object previously occupying its corrected
name is moved to its curator-confirmed April 4 path. No video bytes are
transcoded, replaced, downloaded in full, or newly uploaded. The promoted
object's properties were read from its public MP4 header using HTTP range
requests. Sizes and content identities were read from the Hub repository
inventory.

The later Standard ingestion adds 17 creator-verified media objects totaling
9,289,459,921 bytes. Every addition was fully decoded before upload, all 17
local SHA-256 identities are unique, and none matches an existing Hub media
object. The batch is indexed without changing the 29-field schema.

The July 13 tier promotion moves one existing 141,221,810-byte object from
Pre-Standard to Standard without changing its payload, Xet identity, or stable
record ID. All 1,205 video frames and the audio stream decode successfully.
The clip begins after drawing has started and reaches a completed, signed
endpoint. The promotion moves the protocol identifier coherently to
`standard-2025-07-13` and preserves the 485-record total.

The August 2026 Standard ingestion adds three creator-verified media objects
totaling 50,478,909,746 bytes. All 231,383 video frames and every audio stream
decode successfully. The batch includes the first 14 × 17 in Standard record,
retains `Rec01` because `Rec02` is expected, and preserves the
existing 29-field schema and protocol identifier.

The August 22–23 recording-sequence ingestion adds three creator-verified media
objects totaling 51,022,796,325 bytes. All 233,723 video frames and every audio
stream decode. Rec03 produced one end-of-stream non-monotonic DTS warning from
FFmpeg's null output during combined-stream validation; direct inspection found
strictly increasing source packet and decoded-frame timestamps at the tail. The
batch retains literal `Rec01` through `Rec03` sequence suffixes and documents a
creator-confirmed Rec03 change from Pelikan black to unmarked, unknown-brand
black ink at approximately `00:04:59`.

## Result

**PASS — zero structural validation errors**

| Check | Result |
| --- | ---: |
| Active indexed rows | 491 |
| Canonical Standard rows | 363 |
| Pre-Standard rows | 128 |
| Metadata columns per index | 29 |
| Unique persistent `record_id` values | 491 |
| Unique nonblank content hashes | 491 |
| Complete encoded-video metadata | 491/491 |
| Canonical repository paths matched | 363/363 |
| Pre-Standard repository paths matched | 128/128 |
| Stored-orientation conflicts | 0 |
| Duplicate active content hashes | 0 |

Both Hub builder configurations explicitly declare the same 29 features. This
prevents per-CSV inference from representing an integer-only canonical
`encoded_frame_rate` column as `int64` while representing historical
fractional rates as `float64` in the Pre-Standard configuration.

## Audited statistics

- Total indexed playback duration: 52.647 hours
- Canonical playback duration: 43.052 hours
- Pre-Standard playback duration: 9.596 hours
- Median active-record playback duration: 337.325 seconds
- Total indexed video size: 2.003 TB decimal
- Stored orientation: 479 portrait, 12 landscape
- Audio streams: 485 present, 6 absent
- Unknown finish dates: 9
- Unknown finish times: 62

## Outstanding warnings

1. Fifteen canonical 30×40 records use `support = Paper`, while
   `Archive_Specifications.md` describes the 30×40 support as Illustration
   Board. The curator must determine whether the rows or the specification are
   wrong; this release candidate does not manufacture a correction.
2. Three creator-confirmed Standard records are shortened derivatives rather
   than full-duration masters. Their start/end limitations remain explicit in
   `notes`; none is represented as a complete capture lineage. The promoted
   July 13 record starts mid-process and reaches a completed, signed endpoint.
3. The 2026-01-11 and 2026-02-08 additions each produced one non-monotonic
   duplicate video-timestamp warning during validation but decoded completely.
   Rec03 from 2026-08-23 produced one end-of-stream non-monotonic DTS warning
   from FFmpeg's null output during combined-stream validation, while source
   packet and decoded-frame timestamps at the tail remained strictly increasing.
   The 2026-01-11 recording also has pronounced lighting variation.
4. Five Pre-Standard records retain `time = 00:00` while their finish date is
   unknown. Confirm whether those are documented midnight times or historical
   placeholders before normalizing them.
5. Two Pre-Standard records retain incomplete material fields because the
   filename evidence is insufficient or ambiguous.
6. Most masters retain an audio stream. Stream presence does not establish
   meaningful signal, and rights/privacy review remains necessary.
7. Encoded frame rate is playback rate and cannot be used as original
   drawing-time sampling.
8. The 2012–2016 layer has no public video payload at this snapshot.
9. Separate Hub configurations prevent tier mixing, but no leakage-safe
   train/validation/test partition has been defined.

## Reproduction

Validate both active indexes:

```bash
python tools/validate_metadata.py metadata.csv \
  --pre-standard-metadata Pre_Standard_Time_Lapses/metadata.csv
```

For the strongest repository-inventory check, first augment the pinned Hub API
JSON with the Xet file IDs returned by the same revision's resolve headers:

```bash
python tools/capture_hub_inventory.py \
  --repo-json repo_api_blobs.json \
  --revision "<revision-under-review>" \
  --output repo_inventory_xet.json
```

Then validate paths, Xet identities, and exact byte sizes together:

```bash
python tools/validate_metadata.py metadata.csv \
  --pre-standard-metadata Pre_Standard_Time_Lapses/metadata.csv \
  --repo-inventory-json repo_inventory_xet.json
```

A plain JSON list of repository paths is also accepted through the legacy
`--repo-files-json` spelling, but that checks membership only; it cannot
independently verify hashes or byte sizes.

Use `--viewer-json` only with a Viewer snapshot produced from the same
repository revision and configuration under review.

The Pre-Standard technical enrichment is reproducible from a pinned Hub API
response containing `siblings` with LFS metadata and an FFmpeg executable:

```bash
python tools/enrich_prestandard.py \
  --metadata Pre_Standard_Time_Lapses/metadata.csv \
  --repo-json repo_inventory_xet.json \
  --revision "<revision-under-review>" \
  --ffmpeg /path/to/ffmpeg \
  --cache prestandard_probe_cache.json \
  --output Pre_Standard_Time_Lapses/metadata.csv
```

The revision is intentionally explicit: reproducing against a moving branch
would weaken both identity and technical-metadata claims.

The canonical v0.2 index remains reproducible from its pinned 335-row source
plus the three audited additions:

```bash
python tools/repair_metadata.py source_metadata.csv metadata.csv \
  --additions tools/metadata_additions_v0.2.csv
```