No. 01
"It came from WhatsApp"
Re-encoded, stripped of EXIF, no timestamp authority, no binding to the device that captured it. A defence lawyer rejects it in thirty seconds.
Forensic scene documentation · iOS and Android
Forensic photos, videos and audio,
sealed the moment they're captured.
A single mobile app turns every photo, video and audio recording taken on-site into a signed, RFC 3161 timestamped, BagIt-packaged piece of evidence — ready from the moment of capture.
Coming soon
Locus, tempus, veritas.
Place, time, truth — incontrovertible.
What does Locus do?
It creates multimedia evidence that verifies itself — intact, signed, timestamped and interoperable — with no lock-in to the software vendor.
What is LOCUS
A smartphone that becomes a forensic acquisition device
LOCUS captures photos, videos and audio and wraps them in a self-contained « bundle » — intact, reliably timestamped and verifiable by anyone, with no need to trust the vendor.
Every acquisition produces a package that holds the evidence together with all the metadata, cryptographic signatures and timestamps needed to prove its integrity, authenticity and spatio-temporal placement.
The format is not proprietary: it rests entirely on open standards recognised internationally, so the evidence can be validated with free tools already present on common operating systems.
Privacy first
The server never knows what you captured.
Photos, videos and audio never leave the device except inside the sealed bundle, which stays with you. Only the mathematical proof of the media reaches the LOCUS server — cryptographic hashes, perceptual hashes and any histograms of the generated images — plus the operation metadata. The server checks integrity by fingerprint only: it neither receives nor stores the image, video or audio. Whether it’s a photo, a video or audio, the LOCUS server will never know what it is.
The content travels only with the bundle, according to your documentation needs. On the server, never the scene: only its digital fingerprint.
§ 02 · The gap
A photo on the phone is not evidence.
Three reasons why ordinary captures fall apart the day they are challenged in court.
No. 02
Missing context
Where was it taken? Who was there? Which camera? What time — and according to whose clock? Without context, a photo is just pixels.
No. 03
You only get one shot
You cannot redo a scene survey. Either it is acquired correctly the first time, or the evidence is gone forever.
The Zero-Trust principle
Evidence for a Zero-Trust world.
« Never trust, always verify. » LOCUS brings the Zero-Trust principle to digital evidence: every bundle verifies itself, with free, open tools already present on common operating systems — with no need to take our word, an expert’s or an authority’s. Maths replaces trust.
A hash allows no rebuttal: it matches, or it doesn’t.
§ 03 · How it works
Eleven cryptographic steps,
executed before you put the phone down.
Every step runs automatically on-device. The user shoots; the app seals. No technical knowledge required of the operator.
01
NTP sync
Authoritative time fix from time.cloudflare.com
02
Capture
Native camera, raw frame, no filters applied
03
Watermark
3-line burn-in: time · UUID · GPS+heading
04
EXIF inject
Camera metadata preserved + LOCUS UserComment
05
Triple hash
MD5 · SHA-256 · SHA-512 in one pass
06
RFC 3161 TSA
Sectigo→DigiCert→GlobalSign + InfoCert eIDAS opt-in
07
Ed25519 manifest
Device-bound keypair, manifest signed
08
CASE / UCO
JSON-LD sidecar: Image · Device · Location · Provenance
09
PDF report
Forensic report ready for the case file
10
BagIt assembly
RFC 8493 packaging + tagmanifest TSA
11
Registry + e-mail
Only metadata + fingerprints on the server (never the media), certified e-mail notification
The guarantees
What a LOCUS bundle guarantees
Nine guarantees, each obtained through a cryptographic or data-minimisation mechanism that can be verified independently.
No. 01
Integrity
Two layers of SHA-256 hashes over payload and control files, in BagIt format: changing a single byte makes verification fail.
No. 02
Authenticity
Ed25519 digital signature of the manifest, generated from the device private key.
No. 03
Trusted timestamp
Two RFC 3161 timestamps issued by an accredited Time Stamping Authority (Sectigo).
No. 04
Content provenance
A LOCUS-PROV-v1 manifest embedded in the media itself, for photo and video.
No. 05
Declared fidelity
The capture pipeline is declared in the signed manifest (computational vs raw; no generative AI editing).
No. 06
Traceability
Chain of custody in CASE/UCO format, interoperable with the main forensic tools.
No. 07
Verifiability
Offline verification scripts and a documented manual procedure, with no dependency on the vendor.
No. 08
Confidentiality (privacy by design)
The actual content (photo/video/audio) is never transmitted or stored on the server: it stays in the bundle. Only the histogram and signed perceptual hashes are uploaded; public verification reveals neither the image nor the GPS.
No. 09
Certified notice (IT)
For Italian users with a valid PEC: a certified receipt with independent trusted time, held by a third party.
Inside the app
Acquisition, library and verification in one app
Multi-modal capture
Photo, video and audio — sealed on the device
Italian market
At the end of an acquisition you get a PEC or e-mail notification.
Once the seal is complete, LOCUS automatically sends an acquisition notification. If you have set an Italian Certified E-mail (PEC) in your profile, it is delivered via PEC with a delivery receipt that has legal value (DPR 68/2005, art. 48 of the Italian Digital Administration Code). If you only set a regular e-mail, you receive a plain informational e-mail, with no certified receipt. In both cases the message carries the acquisition report — triple hashes (MD5/SHA-256/SHA-512), RFC 3161 timestamp, manifest signature, device, GPS and NTP data — plus the verification code for independent cross-check. The actual media (photo/video/audio) is NOT carried in the notification and is NOT on the server: it stays in the bundle you keep; online there is only the public verification page with histogram and fingerprints.
- Legal value (with PEC)
- With PEC: a delivery receipt equivalent to registered post with return receipt. With a regular e-mail only: an informational notice, no certified receipt
- Automatic
- No manual step: it fires by itself once the seal is complete (only metadata reaches the server, not the media)
- Lightweight
- Report + verification code only: the media stays in the bundle, never attached
§ 04 · Compliance
Standards baked in.
Not bolted on afterwards.
Conformity references — not certification logos — that govern the bundle structure.
| Reference | Scope | Where in LOCUS |
|---|---|---|
| ISO/IEC 27037:2012 | Identification, collection, acquisition and preservation of digital evidence | Full pipeline |
| SWGDE 18-F-002 · 17-V-002 · 23-I-001 | Digital-evidence acquisition · forensic video/audio · imaging best practices | Capture flow, chain of custody |
| RFC 3161 | Time-Stamp Protocol with authoritative trusted authority | Media + tagmanifest |
| Provenance LOCUS-PROV-v1 | Content provenance, inspired by C2PA/JUMBF (NOT standard C2PA) | APP11 (JPEG) · BMFF uuid box (MP4) |
| CASE 1.3 / UCO 1.4 | Cyber-investigation Analysis Standard Expression | JSON-LD sidecar |
| BagIt RFC 8493 v1.0 | Hierarchical filesystem packaging for transfer | Bundle root |
| EXIF 2.32 | Exchangeable image file format | Preserved unaltered in JPEG |
| eIDAS 910/2014 | Qualified electronic time-stamps (legal value in EU) | Optional via InfoCert TSA |
§ 05 · Who uses it
Twelve professional contexts
where a photo must hold up in court.
LOCUS is designed for those who answer to a judge, an insurer, or a board — not for social-media collectors.
Court-appointed expert (CTU/CTP)
Photographic survey of the contested scene with hash + signature ready to cite in the report.
Police forensics
On-scene survey by judicial police. Bundle attachable to the report.
Fire & rescue investigators
Fire-origin and accident scene documentation.
Site supervisors & surveyors
Construction sites, ATP and structural surveys with unchallengeable photo evidence.
Insurance loss adjuster
Damage assessment that cannot be contested for tampering or backdating.
Private investigator
Lawful documentation packaged for the defence lawyer.
Corporate security
Incident response with verifiable evidence for internal investigations.
Law firm
Evidence collection from the office, immediate delivery to the file.
Agronomist · crop assessor
Dated, geo-referenced crop-damage assessment for compensation.
Conservator · restorer
Dated conservation state of artworks and cultural assets.
Freight forwarder · logistics
Condition of goods at loading/unloading and in-transit damage.
Building / condo manager
State of common areas, damage and leaks in disputes.
§ 06 · Pricing
Pay for what you certify.
A prepaid slot system, designed for legal admissibility. No subscription, no expiration. The more you buy, the lower the unit cost.
How slots are consumed
- 1 slot
- One forensic photo (Sectigo timestamp)
- 1 slot
- One forensic audio recording (Sectigo timestamp)
- 2 slots
- One forensic video (Sectigo timestamp)
- +2
- eIDAS-qualified InfoCert timestamp (per acquisition)
- 2 free
- Sign-up bonus — every new account starts with 2 free slots
Slots are purchased and topped up here on the website, from your account: the mobile app only uses them to acquire. Go to your account →
Starter
5 slots
€ 30
€ 6.00 per slot
- 5 photo/audio or 2 video acquisitions
- Sectigo timestamp
- PEC notification
- Public verification page
Business
50 slots
€ 240
€ 4.80 per slot
- 50 photo/audio or 25 video acquisitions
- Save 20% vs Starter
- eIDAS-qualified option
- Priority email support
- Multi-device
Enterprise
500 slots
€ 1,800
€ 3.60 per slot
- 500 photo/audio or 250 video acquisitions
- Save 40% vs Starter
- eIDAS-qualified on demand
- API access
- Dedicated onboarding
§ 07 · Public verification
Verify a bundle in one second.
Type in the 6-character short code printed in the report or the email and we recompute every cryptographic check live.
Public verification — no login required.
§ 08 · Trust by transparency
And if LOCUS disappeared tomorrow?
The validator still runs offline on any PC.
Locus Validator is the standalone, open-source desktop counterpart of the mobile app — built with the same stack. It recomputes every cryptographic check locally and runs fully offline, with no account required. When a bundle fails and you are online, it can additionally cross-check it against the authoritative server record to pinpoint exactly what was altered — file, hash, signature or timestamp; the only thing it ever sends is anonymous telemetry of validation outcomes — never your identity or the evidence. And if you would rather install nothing: every bundle is self-verifying — it ships with verify.sh/verify.bat and an interactive.html report with in-browser hash validation.
- Offline
- CA certificates of the timestamp authorities are bundled inside the binary. Works air-gapped.
- Cross-platform
- Native builds for macOS (Intel + Apple Silicon), Windows 10+ and Linux x64.
- Open output
- Bilingual PDF report (IT/EN) with the same layout as the LOCUS app — ready to cite in court.
- 9 checks
- BagIt · multi-hash · RFC 3161 ×2 · Ed25519 · provenance (LOCUS-PROV) · CASE/UCO · temporal coherence · audio.
§ 09 · Questions
What forensic teams ask first.
Honest answers, no marketing fluff.
No. Without a connection the RFC 3161 timestamp — the third-party trusted date that gives the acquisition its evidentiary value — cannot be applied, so LOCUS requires an Internet connection to acquire. The Photo, Video and Audio buttons stay disabled until the network is available.
Android 11+ (any vendor, including ruggedised) and iOS 16+. The same bundle format is produced on both platforms.
Slots are purchased and topped up from your account here on the website (the Slots section of your dashboard); the mobile app only uses them for acquisitions and does not sell slots inside the app. Sign in to your account →
The standard timestamp uses public RFC 3161 TSAs in a cascade (Sectigo → DigiCert → GlobalSign), non-qualified. InfoCert is an eIDAS Reg. 910/2014 qualified authority — the timestamp has full legal value in the EU. Both are RFC 3161; legal weight differs.
LOCUS produces robust evidence that any third party can verify independently: a documented chain of custody, cryptographic integrity (hash triple + Ed25519 signature), a trusted date via RFC 3161 timestamp and — on opt-in — an eIDAS-qualified timestamp with full legal value in the EU. Admissibility and evidentiary weight are for the judge to assess case by case: no tool can guarantee them in advance. LOCUS is built to withstand cross-examination — the opposing party, court experts and prosecutors can recompute the checks themselves, even offline, without relying on us.
Absolutely. The bundle is a plain ZIP following the BagIt RFC 8493 v1.0 specification. Any operating system, any text editor, openssl, and a PDF reader are enough to inspect everything.
Two ways: the public web page /verify/<code> on this site, or the standalone offline app Locus Validator (macOS + Windows + Linux).
Every bundle is signed with an Ed25519 key bound to the device (registered TOFU on first use), and the manifest records the operator identity and the device fingerprint. The signature inseparably binds content, device and moment of sealing: a bundle from a different device or operator would carry a different key, detectable on verification.
No — and that is the whole point. Any change, even a single byte, breaks the hash triple, the Ed25519 signature and the timestamp: verification (public page or Locus Validator) detects it immediately and flags the bundle as altered. The evidence is tamper-evident by design.
The actual evidence content (photos, videos, audio) lives only in the BagIt bundle on the user's device, who keeps it and shares it according to their own documentation needs: the user is the custodian of the evidence. On our servers — hosted in the European Union with a GDPR-compliant provider — we keep only account and billing data and the acquisition metadata (cryptographic and perceptual fingerprints, histogram, technical parameters and GPS coordinates): never the actual media. The public verification page discloses neither the image nor the GPS location. Data minimisation is structural (privacy by design) and standard GDPR rights apply (EU Reg. 2016/679): access, rectification, erasure, portability and objection.
No. For confidentiality the actual evidence content (photos, frames, video, audio) is never transmitted or stored on our servers: it stays only in the sealed BagIt bundle you hold. We upload only a histogram image and the perceptual hashes (signed in the manifest): they represent the media without revealing its content. The public verification page shows the histogram — never the real image — and does not disclose the GPS position. The Locus Validator recomputes the histogram and perceptual hashes from the media in the bundle and confirms they match, fully offline.
You are the custodian of the evidence: the actual content lives only in the BagIt bundle you hold, so always keep a backup copy (cloud, NAS or external drive). Our servers keep the verification record and the acquisition metadata — useful to confirm the authenticity of an existing bundle — but not the media: if you lose the bundle we cannot reconstruct it.
The PDF report and the BagIt bundle can be attached as-is. The hash triple and the TSA token are quotable in the report; the signed manifest is the formal proof.
One slot per forensic photo or audio, two per video. The eIDAS-qualified timestamp adds +2 slots. Slot packs start at €30 (5 slots, €6.00 each) and the per-slot price drops with volume, down to €3.00. Dedicated discounts for law-enforcement and public bodies.
No subscription. Slots are bought as you go and never expire: use them whenever you need. They are not refundable in cash. The same wallet is shared with the C.E.R.T.O. desktop suite by AcquisizioniForensi.it.
Create an account, copy your API key from the dashboard and enter it in the app, then point the camera. The forensic pipeline runs on its own. No training required, no installation on a forensic workstation.
Don't make the next on-site survey a story.
Make it evidence.
Two free slots when you sign up. No credit card required. First bundle ready in two minutes.
Coming soon