Chiasm vs iTrace

Chiasm captures gaze data through participants’ webcams for remote online studies and research. It processes webcam frames in real time and produces timestamped gaze coordinates linked to study events, together with session metadata. Researchers can connect it to Qualtrics, jsPsych, or custom web studies through a JavaScript library. Chiasm says studies can include hundreds of participants at once. Researchers can download gaze data from Chiasm or stream it to their own server; when used with platforms such as Qualtrics, data is held on Chiasm’s servers for later export. Webcam video is not stored by default, though limited calibration or validation recordings may be retained with explicit opt-in consent. The service supports Google Chrome on laptops and desktop computers with webcams. Flex has no monthly minimum and costs €0.25 per minute. Starter is €199 per month with 900 participant-minutes included, and Pro is €499 per month with 3,000 participant-minutes included. A 7-day trial is listed.

iTrace is a free, MIT-licensed toolkit for analyzing webcam eye-tracking data, with a scientific core built on NumPy and SciPy. It computes gaze in degrees of visual angle and detects fixations, saccades, and microsaccades using I-VT, I-DT, and Engbert–Kliegl methods. Pupil tools include blink detection and interpolation, preprocessing, and eye-crop segmentation measured in pixels or relative to iris size. Affine screen-space calibration reports calibration error and gaze-quality measures. The command-line tool analyzes gaze CSV files and exports JSON reports. Optional webcam capture uses OpenCV and MediaPipe, and optional interfaces include a local HTML app using FastAPI and WebSockets and a Streamlit dashboard. Live workflows can export derived gaze, pupil, and capture CSVs. By default, the workflow does not save raw eye video or persisted eye-crop images, though live viewing may send a temporary JPEG crop to a browser over a local WebSocket. The project says its checks use synthetic ground truth rather than real eye-tracking data or a reference device. Webcam pupil size is a relative proxy, not a measurement in millimetres.