Documentation
Complete guide to implementing and working with the General Traffic Signal Specification (GTSS).
basic_timings.txt
basic_timings.txt defines core signal timing parameters for each phase, including minimum green, yellow, all-red, pedestrian timings, and leading pedestrian intervals (LPIs).
phase
phase is a unique identifier for each phase of a traffic signal. It is used to reference the phase in other GTSS files.
signal_id
signal_id is a unique agency specific identifier for each traffic signal. It is used to reference the signal in other GTSS files.
ped_walk
ped_walk is the pedestrian walk during which the WALK indication is displayed and pedestrians are permitted to begin crossing.
ped_clearance
ped_clearance is the pedesrian clearance interval defined for the flashing DON”T WALK time provided for pedestrians to finish crossing safely.
leading_ped_interval
leading_ped_interval is the Leading Pedestrian Interval (LPI) time to provide a head start for pedestrians before conflicting vehicle movements recive a green.
min_green
min_green is the minimum green time served for a phase once it is activated.
max_green
max_green is the maximum allowable green time a phase can receive before it must terminate.
yellow
yellow is the change interval following green that warns users of an impending red indication.
all_red
all_red is the clearance interval after yellow when all approaches are red to allow vehicles to safely clear the intersection
veh_recall_type
veh_recall_type defines whether a phase is placed in recall to serve vehicles without requiring detection. See table for options.
| Encoding | Vehicle Recall Types Defined |
|---|---|
| None | The phase is not automatically served and will only run when a vehicle call is detected |
| Min | The phase is automatically served and will run to its minimum green time if no vehicle call is present |
| Max | The phase is automatically served and will run up to its maximum green time regardless of vehicle detection |
| Soft | The phase is eligible to be served without detection but may be skipped or terminated early based on controller logic. |
ped_recall
ped_recall is a boolean value indicating wheather the pedestrian phase is placed on recall to automatically serve the pedestrian phase every call.
Example
phase,signal_id,ped_walk,ped_clearance,leading_ped_interval,min_green,max_green,yellow,all-red,veh_recall_type,ped_recall
1,1,7,25,3,8,40,4,2,Min,true