Extract GPS, accelerometer, and gyroscope data from Race-Keeper .rkd telemetry files.
Race-Keeper "Instant Video" systems (by Trivinci Systems LLC, USA) record synchronized video and telemetry at professional track days and racing events. The telemetry is stored in proprietary .rkd binary files, readable only with the included Windows-only player.
This project provides:
- Two independent parser implementations — Python and Go — producing identical output
- Export to Telemetry Overlay Custom CSV (30 Hz)
- Export to GPX 1.1 for track visualization
- The first public documentation of the RKD binary format
The Race-Keeper USB stick comes with a Windows-only video player. If you're on macOS or Linux, you're stuck with raw .mp4 files and no telemetry.
Original Race-Keeper player (Windows only):
After extracting with this tool and loading into Telemetry Overlay:
The CSV export gives you full control over which gauges to display, their appearance, and positioning - something the original player doesn't allow.
See it in action: Demo video on YouTube — Lamborghini Huracan at Circuit de Mettet, Belgium, with full telemetry overlay (speed, g-forces, GPS track map).
cd python
python3 rkd_parser.py outing.rkd # Export CSV + GPX
python3 rkd_parser.py outing.rkd --info # Print session summary only
python3 rkd_parser.py --all-in /Volumes/RACEKEEPER/ # Batch processRequirements: Python 3.9+ (stdlib only)
cd go
go build -o rkd-parser .
./rkd-parser outing.rkd # Export CSV + GPX
./rkd-parser -info outing.rkd # Print session summary only
./rkd-parser -all-in /Volumes/RACEKEEPER/ # Batch processRequirements: Go 1.21+ (stdlib only)
Both implementations produce byte-for-byte identical CSV and GPX output.
A CSV file ready to load into Telemetry Overlay with:
| Channel | Rate | Source |
|---|---|---|
| GPS position (lat/lon) | 30 Hz (interpolated) | GPS receiver |
| Speed (m/s + km/h) | 30 Hz (interpolated) | GPS receiver |
| Altitude (m) | 30 Hz (interpolated) | GPS receiver |
| Heading (deg) | 30 Hz (interpolated) | GPS receiver |
| Vertical speed (ft/min) | 30 Hz (interpolated) | GPS receiver |
| Satellites, GPS fix | 5 Hz | GPS receiver |
| Accelerometer X/Y/Z (m/s²) | 30 Hz | IMU |
| Gyroscope X/Y/Z (deg/s) | 30 Hz | IMU |
| Pitch angle (deg) | 30 Hz | Computed from accelerometer |
| Bank/roll angle (deg) | 30 Hz | Computed from accelerometer |
| Turn rate (deg/s) | 30 Hz | Gyroscope Z axis |
| G-force longitudinal/lateral/total | 30 Hz | Computed from IMU |
| Braking indicator | 30 Hz | Computed from IMU |
| Cumulative distance (km) | 30 Hz | Computed from GPS |
The utc (ms) timestamp column enables automatic sync with video files in Telemetry Overlay.
A standard GPX 1.1 file at native GPS rate (~5 Hz) for:
- Viewing in Google Earth, GPXSee, Strava, etc.
- Verifying the track layout
- Sharing routes
════════════════════════════════════════════════════════════
RKD Session: outing.rkd
════════════════════════════════════════════════════════════
File size: 474,563 bytes
Car ID: 11098
GPS data:
Fixes: 1,457
Duration: 289s (4.8 min)
Max speed: 156.5 km/h (97.3 mph)
Distance: 5.03 km (3.12 mi)
Alt range: 249.9 – 263.7 m
Satellites: 17 – 19
IMU data:
Frames: 8,681
Accel Z (mean): 9.81 m/s² (expect ~9.81)
════════════════════════════════════════════════════════════
The RKD binary format uses a PNG-style magic signature (\x89RKD\r\n\x1a\n) followed by a sequential stream of typed records with 10-byte headers:
| Record Type | Data | Rate |
|---|---|---|
| HEADER (1) | Config key-value pairs | Once |
| GPS (2) | Position, speed, altitude, heading | 5 Hz |
| ACCEL (7) | 3-axis accelerometer (milli-g) | 30 Hz |
| GYRO (12) | 3-axis gyroscope | 30 Hz |
| PERIODIC (6) | System metrics | ~1 Hz |
| TERMINATOR (0x8001) | Session end marker | Once |
See RKD_FORMAT_SPEC.md for the complete binary format specification.
The samples/ directory contains:
sample_mettet.rkd— A truncated RKD file (~50 GPS fixes from Circuit de Mettet)sample_output.csv— Example Telemetry Overlay CSV exportsample_output.gpx— Example GPX track file
├── python/ # Python implementation
│ ├── rkd_parser.py # Parser, exporters, CLI (standalone, no deps)
│ ├── tests/ # Test suite (77 tests, 100% coverage)
│ ├── pyproject.toml # pytest + coverage config
│ └── Makefile # install, test, lint, clean
├── go/ # Go implementation
│ ├── main.go # CLI entry point
│ ├── rkd/ # Parser package
│ ├── go.mod # Module config
│ └── Makefile # build, test, lint, clean
├── samples/ # Shared test data
│ ├── sample_mettet.rkd # Truncated RKD sample
│ ├── sample_output.csv # Reference CSV export
│ └── sample_output.gpx # Reference GPX export
├── Makefile # Root: test/lint/build all
├── CLAUDE.md # Claude Code contribution guidelines
├── RKD_FORMAT_SPEC.md # Formal binary format specification
├── RESEARCH_NOTES.md # Reverse-engineering narrative
├── SESSION_LOG.md # Claude Code interaction log
└── LICENSE # MIT license
This project was born out of frustration: a macOS user with Race-Keeper track day recordings and no way to use the telemetry data. The proprietary .rkd format had no public documentation, and the official tools only run on Windows.
The format was reverse-engineered in a single day using Claude Code as a collaborative analysis partner. The full narrative of the reverse-engineering process is documented in RESEARCH_NOTES.md, and the Claude Code session transcripts are referenced in SESSION_LOG.md.
If you're here because you want to use Race-Keeper data with Telemetry Overlay:
- Copy your
outing.rkdfile from the USB stick - Run:
cd python && python3 rkd_parser.py outing.rkd(or use the Go binary) - Load the generated
.csvinto Telemetry Overlay as a "Custom CSV" data source - The UTC timestamps will auto-sync with your video
The format specification in RKD_FORMAT_SPEC.md is designed to be implementor-friendly, with:
- Exact byte offsets and struct formats
- Unit conversion formulas with examples
- Validation checksums for testing
- Example hex dumps
The Python parser (python/rkd_parser.py) serves as a reference implementation — it's deliberately written to be readable with extensive inline comments explaining each binary format detail. The Go implementation (go/) is a direct port that produces identical output.
- No OBD-2 data support yet. Race-Keeper systems support OBD-II for logging engine RPM, throttle position, coolant temperature, and more. The
.rkdformat includes OBD-2 record types, but the recordings used for reverse-engineering did not have an OBD-II scanner connected (the header log showed "no connection to OBD2"). PRs with sample.rkdfiles that include OBD-2 data are very welcome — this would allow implementing support for those channels.
Found a Race-Keeper system with different record types or data structures? Contributions welcome:
- Open an issue with a hex dump of the first 256 bytes
- If possible, share a sample
.rkdfile (or the record type summary from--info) - Especially wanted:
.rkdfiles with OBD-2 data for testing and implementation
- Reverse engineering & implementation: @sam-dumont
- AI-assisted analysis: Claude Code (Anthropic)
MIT License — see LICENSE
This project is the result of independent reverse engineering. It is not affiliated with, endorsed by, or connected to Race-Keeper or Trivinci Systems LLC.