fingerprintd/packaging/fptrial.sh
Jorijn van der Graaf a0c8e5b75a Add fptrial.sh: a labelled verification protocol
Thirteen real fprintd-verify runs produced four matches and nine misses and no
rate, because nothing recorded which finger each run used. This script runs the
protocol -- N quick taps with the enrolled finger, then N with a different one
-- tells the user which finger and which tap they are on, and records the label
and the wall-clock latency from prompt to client result per tap. The daemon's
transcript has the frames; this has the labels. A loop change is measured
against this, one variable at a time.
2026-09-02 23:35:20 +02:00

34 lines
1.6 KiB
Shell

#!/bin/sh
# fptrial.sh -- a labelled verification protocol against fingerprintd.
#
# fptrial.sh [correct_taps] [wrong_taps] defaults 10 and 5
#
# Runs fprintd-verify once per tap and tells you which finger to use before
# each one. The daemon's transcript records every frame; THIS records the label
# and the wall-clock time from "press now" to the client seeing a result, which
# is the latency a user feels. Unlabelled runs cannot be turned into a rate.
C=${1:-10}; W=${2:-5}
OUT=/tmp/fptrial-$(date +%Y%m%d-%H%M%S).log
now() { date +%s%N; }
run() { # $1 = label
printf '\n>>> %s -- press and LIFT (quick tap) ... ' "$1"
t0=$(now)
res=$(timeout 20 fprintd-verify user 2>&1 | grep -E 'Verify result' | tail -1)
t1=$(now)
ms=$(( (t1 - t0) / 1000000 ))
verdict=$(printf '%s' "$res" | grep -oE 'verify-(match|no-match|unknown-error)' || echo timeout)
printf '%s (%d ms)\n' "$verdict" "$ms"
printf '%s %s %d\n' "$1" "$verdict" "$ms" >> "$OUT"
sleep 1
}
echo "labelled trial -> $OUT"
i=1; while [ $i -le $C ]; do run "CORRECT $i/$C"; i=$((i+1)); done
echo; echo "===== now switch to a DIFFERENT finger ====="; sleep 3
i=1; while [ $i -le $W ]; do run "WRONG $i/$W"; i=$((i+1)); done
echo
echo "===== summary ====="
awk '$1=="CORRECT"{c++; if($3=="verify-match")cm++; ct+=$4}
$1=="WRONG" {w++; if($3=="verify-match")wm++; wt+=$4}
END{printf " correct finger: %d/%d matched (false negatives %d) mean %d ms\n", cm,c,c-cm,(c?ct/c:0);
printf " wrong finger: %d/%d matched (false ACCEPTS %d) mean %d ms\n", wm,w,wm,(w?wt/w:0)}' "$OUT"
echo " per-tap log: $OUT"