Setup an experiment and save data

sarmad.m

Hi

I'm new to eye tracking and pygaze . my requirement is to build an experiment to display an image or video file then record eye gaze points and fixations . I have started with pygaze temple in opensesame . I have these questions :

1. How can I add video file or image to the experiment , I have added using sketchpad , but for video how to make it as long as the video plays ?

2. After the video file is finished , how the experiment should end and save the data ?

Thanks for help

eduard

1.How can I add video file or image to the experiment , I have added using sketchpad , but for video how to make it as long as the video plays ?

Yes, with sketchpads you can add images. And with the video plugin, you can present videos. Unless you specify something else, the video will run as long as its duration.

2.After the video file is finished , how the experiment should end and save the data ?

Nothing needs to be done. The experiment will stop once no further items needs to be executed. For the data to be written to file you need to add a loggeritem to the experimental sequence. Then every time this logger item is executed, the current trials will be written to the file.

When eye-tracking, the eyetracker software usually writes a seperate logfile with all the eye position samples. You can either opt for combining these two files after you recorded the data. Or you can send Opensesame variables to the eyetracker and it will be added to the eye logfile right away (at least it does so with the Eyelink eyetrackers)

Eduard

sarmad.m

Hi, I i'm using this code below to recored data from eyetribe using pygaze .

when I run the .bat file it just shows ( press space to start calibration ) when I press space just shows a

white calibration dot and stops the program . what could be the problem ?

import os
from constants import *
from pygaze.display import Display
from pygaze.screen import Screen
from pygaze.keyboard import Keyboard
from pygaze.eyetracker import EyeTracker
import pygaze.libtime as timer

 # Initialise a Display to interact with the monitor
 disp = Display()

# Initialise a Keyboard to collect key presses
kb = Keyboard(keylist=None, timeout=None)

# Create a Screen for the image task instructions
inscr = Screen()
inscr.draw_text(text='Please look at the images. \
\n\n(Press any key to begin)', fontsize=24)

 # Create a Screen with a central fixation cross
 fixscr = Screen()
 fixscr.draw_fixation(fixtype='cross', diameter=8)

# Create a Screen to draw images on later
 imgscr = Screen()

# Initialise a new EyeTracker
 tracker = EyeTracker(disp)

# Calibrate the eye tracker
tracker.calibrate()

# Feed the instructions to the Display
disp.fill(inscr)
# Show the instructions
disp.show()
# Wait until the participant presses any key
# (Allowing them to read the instructions at their own pace)
kb.get_key()

# Loop through all image names
for imgname in IMGNAMES:

# Construct the path to the image
imgpath = os.path.join(IMGDIR, imgname)

# Draw the image on imgscr
# (clear imgscr first, to be sure it's clean)
imgscr.clear()
imgscr.draw_image(imgpath)

# Start recording gaze data
tracker.start_recording()

# Display a status message on the EyeLink computer
# (EyeLink only; doesn't do anything for other brands)
tracker.status_msg('Trial with %s image' % (imgname))

# Log trial start
tracker.log('TRIALSTART')

# Feed the fixation Screen to the Display
disp.fill(fixscr)
# Update the monitor to show the fixation mark
disp.show()
# Log the fixation onset to the gaze data file
tracker.log('fixation_onset')
# Wait for the right duration
timer.pause(FIXTIME)

# Feed the image Screen to the Display
disp.fill(imgscr)
# Update the monitor to show the image
disp.show()
# Log the image onset to the gaze data file
# Include the image name in the message!
tracker.log('image_onset, imgname=%s' % (imgname))
# Wait for the right duration
timer.pause(IMGTIME)

# Clear the Display
disp.fill()
# Update the monitor to show a blank screen
disp.show()
# Log the image offset
tracker.log('image_offset')

# Log the end of the trial
tracker.log('TRIALEND')
# Pause recording
tracker.stop_recording()

# Clear the instructions Screen
inscr.clear()
# Write a new message
inscr.draw_text(text='All done!', fontsize=24)
# Feed the new message to the Display
disp.fill(inscr)
# Show the message
disp.show()
# Wait until the participant presses any key
# (Allowing them to read at their own pace)
kb.get_key()

# Close the connection to the eye tracker
# (This will also close the log file!)
tracker.close()

# Close the Display
disp.close()

eduard

Hi,

I'm not sure why but your line, kb.get_key(), is not responding to key presses. For testing purposes, try using a timeout (e.g. 2000 ms), this solved it for me. However, on the long run, you should find out how to initialize a keyboard the proper way. I don't use the pygaze functions myself, so I can't really help there.

So, use this to check if your experimental sequence is alright: kb.get_key(timeout=2000)

Eduard