The open risk since session 2 was "a sustained action sequence could still
break the bitrate", with every clip measured so far being 1.2-1.7 s. Closed by
measurement rather than by sampling clips by hand.
07_motion_survey.py scans a whole stream at 96x72 for the hottest sliding
window of inter-frame difference. On 00223 the spread between the quietest and
hottest sustained 10 s windows is 10.6x, which is the argument for not eyeballing
it. Hottest is t=539.4s, the Singe endgame.
There, with the fixed lam the CLI uses, sasi overshoots 110 -> 129.6 KB/s (+18%)
and scsi 280 -> 373.8 KB/s (+34%). Rate control moves from "insurance, not a
fix" to required, and is promoted above the full-disc survey. The bus is not
broken -- 381.6 KB/s still fits the 488 KB/s figure -- so FINDINGS 21 survives,
at 78% of the pipe instead of a comfortable margin.
Three further corrections fall out:
- The two largest streams on the disc are bonus material. 00216 is the feature
with a burned-in commentary PiP; 00215 is the commentary. 00223 is the clean
9.4 min. A size-ranked survey would have encoded live action.
- On hard content the 256-colour scene palette (31.33 dB) binds well before the
X68000 display (40.81 dB); scsi is already within 0.51 dB of it.
- FINDINGS 24.5's architecture question resolves to "both paths, chosen per
frame": 30-53% of frames sit above the 70% crossover. Picking per frame costs
a median 37.0% of the frame budget and caps at 53.6%. Reporting for this is
wired into encode.py, which previously only printed a mean over all frames --
the one statistic that cannot answer a per-frame question.
extract.py takes optional start/dur; 08_mode_map.py renders source | decoded |
block-mode map to .webm.
Claude-Session: https://claude.ai/code/session_01194oWYW8DQXK1SZ2DnChW6
prosolis
e00264a058