Per-file digest
Every archived file carries its digest in the manifest, so a single altered byte becomes detectable.
Photo archiving
Photo archive software that proves what it preserves.
Obscura Flow turns a scattered photographic body of work into documented, verifiable, restorable archives, without ever moving your originals off your own disks.
In short
Photo archiving means preserving images and their context in a way that stays verifiable over time. Obscura Flow builds compressed archive packages carrying a SHA-256 manifest and an Ed25519 signature, then periodically checks that nothing has drifted.
- SHA-256 manifest covering every file in an archive
- Verifiable Ed25519 signature for the whole package
- Optional AES-256-GCM encryption
- Scheduled fixity audits and format validation
- Verified restore with overwrite safeguards
- Local macOS application: originals never leave your disks
Evidence
Archive signature
The complete package is signed. Verification separates an intact archive from one modified after the fact.
Compression
Packages are losslessly compressed in a documented format rather than a proprietary container.
An archive is not a backup
A backup answers "do I still have a copy". An archive answers "can I still understand, prove, and use what I kept". Both are necessary, and neither replaces the other.
- Backup
- A recent copy of a working state, replaced every cycle. It protects against hardware failure and mistakes.
- Archive
- A frozen, documented, sealed state meant to be read again in ten years. It protects against forgetting and decay.
- What links them
- An archive must itself be backed up off-site, following the 3-2-1 rule.
- What separates them
- A backup says nothing about what the images contain or why they were kept.
What makes an archive readable in ten years
The question is not whether the files will still exist, but whether they will still make sense. A useful archive carries its own context.
- Context
- Who, what, where, when, how, why: structured indexing gives every image a searchable description.
- Identifiers
- A persistent inventory number survives file renames and folder reorganizations.
- Metadata
- EXIF, IPTC, and XMP are read then enriched in XMP sidecars, a standard format other tools can read.
- Formats
- Format validation flags files whose future readability is at risk, before they become unreadable.
Verify instead of assuming
Silent corruption gives no warning: a damaged file still opens, until the day it does not. Regular auditing is what separates an archive from a pile of files.
- Fixity audit
- Digests are recomputed and compared against the manifest. Any drift is reported.
- Signature check
- The Ed25519 signature confirms the archive has not been altered since creation.
- Scheduling
- Audits are planned, so they do not depend on a manual reminder everyone ends up postponing.
- Verified restore
- A restore checks the signature before extracting, and offers to preserve existing files rather than overwrite them.
Step by step
Build a verifiable photographic archive
The full path, from importing an existing body of work to the first fixity audit.
Import the collection
Copy, move, or reference existing folders and media. SHA-256 deduplication removes duplicates and automatic resume survives interruptions.
Document
Enrich EXIF, IPTC, and XMP, apply structured indexing, and assign persistent inventory numbers.
Structure
Group into projects, collections, and series. Smart collections follow rules without duplicating files.
Seal
Create the archive package: zstd compression, SHA-256 manifest, Ed25519 signature, and AES-256 encryption where the context requires it.
Copy off-site
Send the archive to S3, Backblaze B2, Cloudflare R2, a NAS, or a local folder, with resumable transfers.
Audit
Schedule fixity audits and format validation, then test a restore: a backup you never restored is not a backup.
Questions
How is archive integrity verified?
Each archive includes a SHA-256 manifest and an Ed25519 signature. Scheduled fixity audits and format validation reveal drift or corruption.
How does restore work?
Verified restore extracts a local or off-site archive after signature checks, with conflict options and overwrite safeguards.
How often should an archive be verified?
A quarterly fixity audit is enough to catch silent corruption before it propagates into backups. Scheduled audits remove the need to remember.
Are encrypted archives portable?
AES-256-GCM encryption is optional. An encrypted archive can only be restored on the Mac that created it because the key stays in that Mac's keychain.
Are my original files modified?
No. The app is non-destructive: enriched metadata is written to XMP sidecars, never into the original files.
What happens if I stop using Obscura Flow?
Your originals never left your disks, and metadata is written to XMP sidecars, a standard format other tools can read. Archives remain packages accompanied by their manifest: nothing depends on the application still being installed.
Decision
Build an archive that stays understandable.
Tell us about your context before the public opening of downloads and commercial offers.