# PNG compression experiment — October 30, 2026

Original RGB illustration, 640x480. Pillow saves compress_level=0 and 9; no resize, alpha or ICC profile. inputs.json records encoded and decoded SHA256. prepare.py and test.mjs reproduce inputs and two Chrome UI conversions from the current production snapshot. Clean Outline, A4. Download button files compared by encoded SHA256 and decoded RGB difference: zero changed pixels. Chrome 156.0.8078.74. app.js SHA256 fb728a912378c8e7350a98bbbe3b656a5da1c96955411e3c3ec9e83b30dea13c; public script verified identical. Measurements are in measurements.json. Figure contains real exported pages resized for display. Not photographs, performance testing, competitor conversion tests or physical printing. Manual execution requested by user; no scheduled-on-time claim.