-
Notifications
You must be signed in to change notification settings - Fork 0
FAQ
A .ddd file is a binary download from a digital tachograph. It contains all recorded data from a specific period: driver identity, vehicle information, daily activity records (driving, work, rest), GNSS (GPS) positions, events, faults, and digital signatures that prove the data has not been tampered with.
There is no standard tool to open .ddd files on a normal computer. This application is designed to fill that gap.
| Driver Card (Carta) | Vehicle Unit (VU) | |
|---|---|---|
| Source | Downloaded from the driver's personal tachograph card | Downloaded from the tachograph unit installed in the vehicle |
| Contains | One driver's activities across multiple vehicles | Activities of all drivers who used that vehicle |
| Typical use | Driver monitoring | Fleet management, vehicle usage analysis |
The application detects the file type automatically and adapts the section tree accordingly (e.g., VU-specific sections such as sensor pairings, company locks, and detailed speed blocks only appear for VU files). Detection is content-based, so a driver-card image wrapped inside a VU download is still recognised and shown as a driver card.
These are mostly the same EU tachograph download with a different file extension, chosen by a country or by the download software rather than by a different data standard:
-
.V1B— vehicle unit (mass memory), French naming. -
.C1B— driver card, French naming. -
.TGD— vehicle or driver file, Spanish naming. -
.ESM— vehicle or driver file produced by some third-party download tools.
The actual tachograph content is defined by the EU specifications (Annex 1B / Annex 1C), not by the extension. When the file holds the raw binary download, it is the same data as a .ddd, and you can open it by choosing All Files in the open dialog (or renaming it to .ddd).
The main exception is .ESM: some tools wrap or compress the payload (for example inside an archive) or emit a non-binary export. In that case the extension alone is not enough — the raw download has to be extracted first. If one of these files does not open, please open an issue with an anonymized sample so support can be confirmed.
These are the three generations of digital tachographs:
- G1 (Generation 1): The original digital tachograph standard (Annex 1B of Reg. 3821/85). Uses STAP encoding.
- G2 (Generation 2): First-generation Smart Tachograph (Annex 1C, Reg. EU 2016/799). Uses BER-TLV encoding. Adds GNSS recording and remote communication.
- G2.2 (Generation 2.2): Second-generation Smart Tachograph (Reg. EU 2023/980). Adds new fields (border crossings, load/unload operations, trailer registrations) and enhanced security.
The application automatically detects which generation a file belongs to from the file header (0x7631 = G2.2, 0x7621/0x7622 = G2, otherwise G1).
GNSS positions are recorded by the tachograph at specific intervals (typically when the vehicle starts, every 3 hours of accumulated driving, and when it stops). Not every minute of driving has a GPS coordinate. Additionally, G1 tachographs do not have GNSS capability at all. Gaps in position data are normal and expected.
Byte coverage is the proportion of the .ddd file that the parser can interpret. Full coverage means every byte was accounted for (decoded data plus recognised padding). The reader sweeps any bytes missed by the structural walk and classifies them as padding or tracked unknown ranges, so undecoded regions are never silently dropped. All test files in the project achieve full coverage.
The parser is deterministic-first and resilient: it decodes according to the EU specification wherever possible, and falls back to best-effort recovery only when needed. For VU downloads it reports TREP completeness (which mandatory sections are present, missing, or suspect). If a file is genuinely partial or corrupted, the reader shows a CORRUPTED / PARTIAL FILE page listing what was recovered and what was discarded. Anything reconstructed by salvage is clearly flagged as low-confidence, so it is never confused with cleanly decoded data. Implausible values (for example an impossible speed) are dropped rather than displayed.
No. The tool is a parser and integrity validator: it decodes the recorded activities and verifies the digital signatures, but it does not currently evaluate driving-time or rest-period rules and does not estimate fines. You can export the activity data to JSON or Excel and run your own compliance analysis on it.
Yes. All processing is local — your .ddd files never leave your computer. There is no cloud upload, no telemetry, and no data sharing. Signature verification uses the ERCA root certificates bundled with the application in the certs/ folder.
Open an issue on the GitHub repository. Please include:
- The operating system you're using
- The
.dddfile generation (G1, G2, or G2.2) - A description of what happened vs. what you expected
- Any error messages displayed
- Reg. 3821/85 (Annex 1B): Original digital tachograph specification
- EU 2016/799 (Annex 1C): Smart Tachograph data specification
- EU 2021/1228 and EU 2023/980: Smart Tachograph V2 data specification
No. The application is read-only. It parses, analyzes, and exports data from .ddd files but never modifies them. This ensures the original file remains forensically intact.
The application is developed and tested on Windows and macOS. If you are comfortable running Python scripts, you can use the from-source installation on Linux by running python app/gui.py or the CLI tools. However, Linux is not an officially supported platform for the pre-built executables.
User Manual
Help
Links