PTU ROI LabLocal analysis · your files stay in this browserMethods & limits

BCECF / FLIM WORKSPACE

From photons to a selected region.

Open a PTU raster, mark your objects, then inspect their decay and scan-encoded structure.

No file opened. Single-raster T3 imaging files are supported; acquisition metadata are checked before analysis.

Photon-count image

Native pixels
Open a PTU file
The photon image will appear here.
Brightness represents photon counts, not fluctuation amplitude.
Select pixels by coordinates

Zero-based column (x) and row (y).

Selection stays independent of the expected biological result.

03 Results

Waiting for a region
Selected ROIs
Selected pixels
Photons

Fluorescence decay

The pooled photon decay of an ROI, in nanoseconds.

Scan-encoded structure

0–20 Hz scan-coordinate analysis.
Not a temporal oscillation spectrum.

Several selected ROIs can be calculated jointly. Very small regions may not support this descriptor.

Noise-adjusted Photon-noise estimate
What is measured — and what is not

Pixel selection

The image is reconstructed from photon arrival times and recorded line markers, including the recorded sinusoidal scan correction. Contrast is for display only. Bright pixels are candidates, not proof of mitochondrial identity.

Lifetime observable

We pool microtime histograms within each ROI and calculate a finite-window, background-adjusted decay centroid in ns. This is not an IRF-deconvolved exponential lifetime fit, and it is not an absolute pH measurement.

The 0–20 Hz curve

A dwell-integrated harmonic basis is evaluated at recorded pixel acquisition times. Per-ROI means are removed and photon-noise contributions are subtracted. The result is a signed scan-encoded spatial descriptor in ns², not a temporal PSD or evidence of resonances.

File handling

PTU processing runs in a browser worker. Raw files, selections and calculations are not uploaded by this app or stored on its server. Download masks and results before closing the page. The site does not provide shared project storage.