ALPR Traffic Counting Service¶
The ALPR Traffic service combines traditional traffic counting with Automatic License Plate Recognition (ALPR). For each counted vehicle crossing your measurement cross-sections, the system captures and recognizes the license plate, providing detailed vehicle identification alongside traffic statistics.
Use Cases¶
- Origin-Destination (O-D) studies - Track vehicles between multiple measurement points
- Toll road analysis - Monitor vehicle passages with license plate evidence
- Traffic pattern research - Correlate license plate data with traffic flow
- Fleet monitoring - Track specific vehicle groups through measurement zones
- Border crossing analysis - Document vehicle movements between regions
Camera Requirements¶
Fixed/Stationary Cameras¶
Cameras mounted on poles, bridges, or permanent structures above or beside the road.
Daytime requirements: - Resolution: Full HD (1920×1080) minimum - Frame rate: 20-30 FPS - Clear view of license plates (front or rear) - Optimal angle: 15-45° to the road surface
Nighttime requirements: - Infrared (IR) illumination recommended - Fast shutter speed (1/500s or faster) to avoid motion blur - Low-light capable sensor - Individual camera calibration may be required
Note: Night-time ALPR accuracy depends heavily on camera setup. Contact us for professional assessment and camera configuration guidance.
Generated Reports and Data¶
The ALPR Traffic service produces comprehensive reports combining traffic counting with license plate recognition data.
Output Files¶
| File | Description |
|---|---|
History.csv |
Complete vehicle history with all data fields |
Alpr.csv |
Filtered ALPR-specific data |
Alpr0to500.xlsx, Alpr500to1000.xlsx, ... |
Excel sheets with vehicle images and license plate crops (paginated for large datasets) |
AlprOccurences.csv |
License plate occurrence matrix grouped by time intervals |
Quantity.csv |
Standard traffic counting results |
Report.docx |
Generated measurement report |
Data Fields¶
Each recognized vehicle record contains:
| Field | Description |
|---|---|
ALPR |
Recognized license plate text |
ALPR_score |
Recognition confidence (0.0 - 1.0) |
ALPR_type |
License plate type classification |
ALPR_region |
Region/country code (e.g., "PL", "DE") |
ALPR_lettercode |
District/city letter code (e.g., "WA" for Warsaw) |
ALPR_image |
Cropped license plate image path |
Image |
Full vehicle image path |
Recognition Statistics¶
The system calculates ALPR totals for quality assessment:
| Metric | Description |
|---|---|
| Total vehicles | All counted vehicles in measurement |
| ALPR detected | Vehicles with license plates detected |
| ALPR read | Vehicles with successfully read plates |
| Region recognized | Plates with identified region codes |
| Letter code recognized | Plates with identified district codes |
Polish License Plate Recognition Details¶
Polish standard license plate format: XX YYYYY or XX 123AB
- First 2 characters: Region/district code (e.g., "WA" for Warsaw, "GD" for Gdańsk)
- Remaining characters: Vehicle registration number
Common Polish region codes (ALPR_lettercode):
| Code | Region | Code | Region | Code | Region |
|---|---|---|---|---|---|
| BA | Białystok | PZ | Poznań | TO | Tarnów |
| BN | Bielsko-Biała | RZ | Rzeszów | WA | Warsaw |
| DS | Dolnośląskie (Wrocław) | SL | Silesian (Katowice) | WR | Wrocław |
| GD | Gdańsk | SZ | Szczecin | WN | Włocławek |
| GO | Gorzów | SK | Świętokrzyskie | ZG | Zielona Góra |
| KA | Kalisz | PM | Pomeranian | ||
| KI | Kielce | KR | Kraków | ||
| KO | Koszalin | LD | Łódź | ||
| LE | Legnica | LU | Lublin |
Plate type classifications (ALPR_type):
- STANDARD - Regular vehicle plates (white background)
- EU - EU format with country symbol
- COMMERCIAL - Yellow plates (taxis, rental vehicles)
- AGRICULTURAL - Green plates (farm vehicles)
- DIPLOMATIC - Special format (embassies, international organizations)
- TRANSIT - Temporary transit plates (red border)
Understanding ALPR_score in Polish context:
- 0.95-1.0 = Excellent read (new, clean plates)
- 0.85-0.95 = Good read (standard conditions)
- 0.75-0.85 = Acceptable (typical Polish plates, some wear)
- 0.60-0.75 = Marginal (dirty, faded, or obscured)
- < 0.60 = Poor read (manual verification recommended)
Excel Reports with Images¶
For detailed analysis, the system generates Excel files containing:
- Vehicle thumbnails in the
Imagecolumn - Cropped license plate images in the
ALPR_imagecolumn - All metadata fields for filtering and analysis
Note: Excel files are paginated (default 500 rows per file) to ensure stability with large datasets.
Accuracy¶
| Condition | Expected Accuracy |
|---|---|
| Daytime, clear weather | 85-95% |
| Nighttime with IR | 70-85% |
| Rain/snow | 60-80% |
| Dirty plates | 50-70% |
Overall measurement error (including traffic counting): ~10%
Polish ALPR Use Cases¶
Origin-Destination Studies (O-D Studies)¶
Track vehicle movements between multiple measurement points using the ALPR_lettercode field:
- Vehicles from "WA" (Warsaw) heading to "GD" (Gdańsk)
- Commute patterns between major cities
- Regional transit analysis
Analysis example:
Count vehicles with ALPR_lettercode = "WA" → Group by destination ALPR_lettercode
Result: "How many Warsaw vehicles traveled to Gdańsk today?"
Fleet Monitoring¶
Track specific company vehicles by plate recognition across multiple routes.
Toll Road Analysis¶
Monitor vehicle classifications and plate regions for toll billing and traffic analysis.
Processing speed: x3 real-time for 20 FPS video