The frame-rate test sylpheed-port and I agreed was the only clean route left.
Same strips, same screen, --framerate_limit=15 against the default. The limit
demonstrably took effect: the title settled at 862 s against 241 s.
First, a gate this work should have had from the start. A slope is only a rate if
its residual is random, so count sign changes in the residual:
default 1299x1303 -4.348 rms 3.33 43/111 OK
883x1134 +4.284 rms 3.08 21/76 SYSTEMATIC
890x1134 +4.284 rms 3.19 15/54 SYSTEMATIC
limit 15 1299x1303 -2.032 rms 1.51 44/83 OK
883x1134 +2.003 rms 1.12 36/61 OK
890x1134 +1.999 rms 0.74 12/37 SYSTEMATIC
So one of the two strips I quoted as "agreeing to three significant figures"
FAILS the linearity gate at default fps: that agreement was between a rate and a
slope through a curve. The port had already caveated the claim for a different
reason; this weakens it further from my own side.
The result, on the one group passing the gate at both settings: -4.348 px/frame
at default against -2.032 at limit 15, a ratio of 2.14.
THE LEAF IS NOT FRAME-LOCKED. A fixed number of units per submitted frame
predicts px/frame unchanged; it changed by 2.14x. Dead.
A simple wall-clock model is dead too, in the other direction: fewer frames per
second means more wall time per frame, so a time-driven leaf should move MORE
px/frame at a lower limit. It moved LESS. Neither model fits and I have no third.
Reach: the effective frame rate was NOT measured. The timing instrument I added
polls for the capture log, which is created when the capture is ARMED rather than
when it finishes, so it reported 0.728 s and is void. The 3.6x boot slowdown says
the limit took effect, not that fps went 28 -> 15. The RATIO is measured; the
absolute rate still is not.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wuu56cE8vJGTBtn1ppsk8v
1538c3e333