README.md

Convert Pupil Time to System Time in RStudio

This script shows how to convert Pupil Time to System Time and store timestamps in DateTime format.

pupil_to_system_timestamps.R

# Load packages
library(readr)
library(tidyr)
library(lubridate)

# Load the desired .csv and info.player.json files from Pupil Player exports
data <- read_csv("../../../../data.csv")
info_player <- read_csv("../../info.player.json")

start_time_system <- extract_numeric(info_player[9,]) #System Time at recording start
start_time_synced <- extract_numeric(info_player[8,]) #Pupil Time at recording start

# Calculate the fixed offset between System and Pupil Time
offset <- start_time_system - start_time_synced

# Add the fixed offset to the timestamp(s) we wish to convert
data$system_timestamp <- data$pupil_timestamp+offset

# Convert System Time timestamps in datetime format
data$datetime <- as_datetime(data$system_timestamp, tz="UTC") #change tz accordingly to your timezone