# Byte-exact recovery receipt: frame 000511

**Status:** authenticated locally on 2026-07-27 and authorised by the owner for
public recovery release on 2026-07-29. This unsigned receipt does not alter any
historical signed release.

One emission frame from the April 2023 Truth Beam PoliePals Trailer record had a
single 262,144-byte UnixFS block that could no longer be retrieved from the
original pin. A numerically faithful reconstruction was published and kept every
surviving byte unchanged. The complete byte-exact frame has now been recovered
from a retained backup.

## Recovered artifacts

| Artifact | Bytes | SHA-256 | CIDv0 |
|---|---:|---|---|
| `000511_bc48b046016adb2ed149471ab0f683f5a9d8dbff9cd544ba2048231c1a4007b2.npy` | 12,583,040 | `6b7a6bc9f052d78dd161d20c22a19a6341f1447af6721a96f72425ce4bce9c1a` | `QmTy4beHLQP71oS1oMtqgNDg3TNU6wirKGfDsf2Rvq6tBr` |
| `lost_block_32.bin` | 262,144 | `f035c6ef0f25ca20d1a9bda8d88cce591be70abb9b209d7c6841f43293a59041` | `QmRyXZyDbVaE6V7vKBL873DwhA8Xb5VSX7ujcoM1kp3Hpx` |

The NPY is a valid C-order array with shape `(1024, 1024, 3)`, dtype
little-endian `float32`, and a 128-byte header. The recovered block is exactly
file bytes `[8,388,608, 8,650,752)` of that frame.

## Authentication

The result is authenticated by measurements that do not depend on the backup
story:

1. `ipfs add --only-hash --cid-version=0` reproduces both CIDs above. Those
   target CIDs were already present in public repository history at commit
   `d294b0d53f29f31e309e3f1fa8fc4083a3f16029`, before this recovery.
2. Against the published reconstruction, every byte before and after the missing
   block is identical. All 15,658 differing bytes are confined to that block.
3. Inside the block, 49,944 of 65,536 float32 values are already bit-identical
   in the reconstruction, or 76.20849609375 percent. The maximum absolute error
   is `1.52587890625e-05`, matching the published reconstruction account.
4. The recovered standalone block is byte-identical to the corresponding slice
   of the recovered full frame.

The complete machine-readable record is
[`RECOVERY_RECEIPT.json`](RECOVERY_RECEIPT.json).

## Availability

This recovery release includes the exact NPY and recovered block through the
existing public data layer:

- [`000511_bc48b046016adb2ed149471ab0f683f5a9d8dbff9cd544ba2048231c1a4007b2.npy`](../../pinata/RECOVERED_truth_beam_poliepals_trailer/000511_bc48b046016adb2ed149471ab0f683f5a9d8dbff9cd544ba2048231c1a4007b2.npy)
- [`lost_block_32.bin`](../../pinata/RECOVERED_truth_beam_poliepals_trailer/lost_block_32.bin)

Publication is complete only when the upload receipt records a fresh download
of each object with the expected byte length and SHA-256. The original owner
archive remains the custody source.

## Recorder-source provenance

The local archive also retains the April 2023 recorder associated with session
`1682718815`. Its 777 original `E`/`R` chain records match every emission and
report filename, and all 776 inter-record BLAKE3 transitions recompute without
error. The public source copy,
[`truth_beam_2023_REDACTED.py`](recorder-source/truth_beam_2023_REDACTED.py),
differs from the archived file only in a security header and replacement of its
hard-coded RSK signing private key with an environment-variable lookup. The
archived original SHA-256 is
`432f08d7a44850c1be3f682eb24e83e0469f3079de48eed546c1345b51969123`.

## Preservation and scope

The byte-exact frame enables repair of the decomposed public mirror. The earlier
reconstruction remains published under its distinct name because it documents a
useful deterministic-recovery result and the float reproducibility lesson.

The historical root CID remains
`QmejyJWognSYn7UhygsHuQzkDK5vY4izU9SsCL785NsHCN`. Its existing CAR remains
labelled **partial** until a complete CAR is rebuilt from the restored bytes and
the root CID is independently reproduced. No historical signed manifest,
signature, CID, or release byte is changed by this unsigned recovery record.

## Reproduce the file checks

```sh
sha256sum 000511_bc48b046016adb2ed149471ab0f683f5a9d8dbff9cd544ba2048231c1a4007b2.npy
sha256sum lost_block_32.bin
ipfs add --only-hash --cid-version=0 -Q 000511_bc48b046016adb2ed149471ab0f683f5a9d8dbff9cd544ba2048231c1a4007b2.npy
ipfs add --only-hash --cid-version=0 -Q lost_block_32.bin
```