C.E.R.T.O.
C.E.R.T.O.
Forensically acquire and analyse a user-supplied image: full metadata, geolocation, perceptual fingerprints and tampering indicators, sealed into a verifiable bundle.
C.E.R.T.O.'s Images module performs the forensic evidence collection of an image supplied by the operator and runs an in-depth analysis on it: it extracts EXIF/IPTC/XMP metadata and GPS data, computes cryptographic and perceptual hashes and runs ELA, histogram, Luminance Gradient, Level Sweep and the examination of the JPEG quantization tables. Everything is sealed as digital evidence with a double RFC 3161 timestamp and an Ed25519 signature. It is the tool for court-appointed and party experts, lawyers and law enforcement who must certify a photo and document its authenticity and traces of re-processing.
A repeatable, documented procedure: from the cryptographic fingerprint to the in-depth pixel analysis, every examination of the image leaves a verifiable trace inside the bundle.
Multi-source NTP sync with documented offset and roundtrip: the moment of evidence collection is anchored.
Computation of MD5/SHA-1/SHA-256/SHA-512 on the supplied original image, as is, before any processing: the integrity reference.
Full extraction of embedded metadata — camera, lens, shooting parameters, dates, GPS, author, copyright and C2PA provenance — formatted and human-readable.
Four algorithms (aHash, dHash, pHash, wHash) at three bit depths: fingerprints of the visual appearance, useful to find the same image or detect modified versions.
Error Level Analysis (ELA), histogram, pixel statistics, Luminance Gradient, Level Sweep and JPEG quantization tables with quality estimation.
Reconstruction, from XMP metadata, of the software and tools used, the derivation chain and the Content Credentials (C2PA), distinguishing development from tampering.
Generation of a watermarked version (for review) alongside the authoritative original, with their respective hashes side by side.
manifest.json signed with Ed25519 + double RFC 3161 timestamp, packaging into a BagIt 1.0 bundle with a CASE/UCO description and verify.sh / verify.bat verifiers.
C.E.R.T.O. does not just certify the file: it studies its pixels and metadata with image-analysis tools, to document its authenticity, history and any traces of re-processing.
If the photo contains GPS coordinates in its EXIF metadata, C.E.R.T.O. extracts them and places them on an OpenStreetMap map, documenting the place where the shot was taken as an element of evidence.
Recompresses the JPEG and amplifies the differences: re-processed areas tend to show a different error level. An indicative, not conclusive, technique.
Tone distribution per channel (R/G/B/Luminance) with clipping, entropy, sharpness and dominant colour: an objective baseline for comparison.
The 8×8 matrices that encoded the JPEG: they are the “encoder fingerprint” and, if non-standard, indicate the saving program or a recompression.
Maps the direction of light on surfaces: edges or areas with lighting inconsistent with their surroundings are a classic copy-paste cue.
Highlights pixels at a given tonal level, linked to the histogram: a pasted region often has a slightly different tonal distribution.
Software, tools, derivation chain and Content Credentials (C2PA) from XMP metadata: distinguishes normal photographic development from tampering.
Each evidence collection produces a coordinated set of artefacts, each with a precise forensic role, organised into clearly-named folders inside data/.
The file supplied by the operator, kept as is with its own hash: it is the authoritative media of the bundle, never re-processed.
evidence/<immagine>
A C.E.R.T.O.-watermarked copy for review and sharing, with its own hash distinct from the original's.
evidence/<immagine>_watermarked
The embedded metadata extracted and formatted: shooting parameters, dates, GPS, author, copyright, software and C2PA provenance.
reports/exif-report.txt · metadata/
The fingerprints of the visual appearance (aHash/dHash/pHash/wHash at 64/144/256 bits), to find the image or detect modified versions.
hashes/perceptual-hashes.json
The analysis outputs: ELA, histogram and statistics, Luminance Gradient, Level Sweep, quantization tables and the embedded EXIF preview.
reports/analysis/
The report in PDF and TXT with its own RFC 3161 timestamp and the complete hash inventory (MD5/SHA-1/SHA-256/SHA-512) of all artefacts.
reports/report.pdf · hashes/file-hashes.json
The bundle does not need C.E.R.T.O. to be validated: anyone, even years from now, can verify its authenticity with standard tools. The BagIt 1.0 structure and the interactive dashboard make it self-explanatory.
data/tsa.tsr and outer seal on tagmanifest-sha256.txt.tsr. Free cascade Sectigo→DigiCert→GlobalSign; optional qualified eIDAS InfoCert.Forensic image evidence, in-depth analysis, photo authenticity and bundle verification: the most common questions.
Register for free and download C.E.R.T.O. Desktop for Windows and macOS from your client area.