dapkel

Data Analysis Package for the Kelpie v2 SPAD camera.

Every analysis here is the same pipeline with a different reduction in the middle:

folder of .bin  →  discover files  →  fold frames into a sensor map
                →  scale to physical units  →  save
                →  load  →  plot

The three stages

stage	what it does	on disk
0. raw	the camera writes .bin; dapkel decodes it	*.bin (read-only)
1. process	fold frames into an array, scale to units, save	processed/
2. plot	load the saved array, render figures	results/<kind>/

The rule that keeps this honest: processed/ holds data, results/ holds pictures, and stage 2 never re-unpacks .bin files. Retrying a colormap costs a load, not a full re-read of the raw data.

Start here

On a fresh acquisition, run the data-quality check first. A TDC that never stopped produces data that looks completely normal to every other analysis in this package.

The analyses

• Decoding .bin files — the shared foundation
• Dark count rate — per-pixel DCR maps in cps
• Optical cross-talk — including the clockwise SPAD geometry
• Hitmaps — occupancy and photon rate
• TDC calibration — the code density test
• Coincidences — delta-t and timing jitter
• Background subtraction — measure the accidental background by shifting frames instead of fitting it
• Data quality — check the run before trusting it

Reference

• Adding an analysis — the contract for new measurements
• The triangular delta-t background — why a flat fit inflates the jitter
• dapkel.core — the shared substrate
• Open items — what is known to need deciding, and why it has not been

Plot styling

Importing dapkel applies its matplotlib house style through komorebi_mpl, so plots look consistent out of the box. Your choice always wins:

import dapkel                     # applies the default style on import
import komorebi_mpl
from dapkel.functions import hitmap_analysis

komorebi_mpl.use("night_wave")    # or any registered style, or "default"
hitmap_analysis.collect_and_plot_hitmap(path)   # stage 2: reads the saved map

The plotting functions never touch rcParams themselves, so whatever style is active when they draw is what you get — set it once, after the imports.

Figure sizing follows one rule: square sensor maps are 16×16 in code (core.plots.sensor_map does this), everything else takes figure.figsize from the active style.