Task 146: Video Frame OCR — On-Screen Data Extraction

Status: DONE

Motivation

SOLAR LINE episodes display ship instrument readings, navigation data, and orbital

parameters on screen (HUD displays, cockpit readouts, status panels). These provide

a primary source for verifying analysis parameters that is more reliable than

auto-generated subtitles.

Human directive: build OCR infrastructure as additional data source (see ideas/ocr_speech_to_text.md).

CLAUDE.md: "Video analysis: Downloaded video (gitignored) may be used for frame-by-frame OCR"

Approach

• Used ffmpeg to extract 21+ key frames from EP01 video at timestamps identified

from dialogue data (technical parameter mentions)

• Manual visual reading of frames by Claude (multimodal vision)
• Structured data extraction into JSON format

Key Findings — EP01 On-Screen Parameters

Navigation Display at 10:54 (JO-DIRECT ENTRY)

Most data-rich frame in the episode. Shows full navigation overview:

• V∞ = 12.0 km/s (hyperbolic excess velocity at Jupiter SOI)
• Entry velocity = 17.8 km/s (at 20.0 RJ, Jovian Center frame)
• Azimuth = 282.14°
• BURN SEQUENCE:

- Phase 1: CRUISE ACCEL (Mars → Jovian Sphere) — Completed

- Phase 2: FULL BURN ENTRY — ΔV = +2.4 km/s, T-11:42:18

- Phase 3: PERIJOVE OVERSHOT CORRECTION — ΔV = -2.3 km/s, window ±5:00 min

• Perijupiter altitudes: 1.5 RJ and 2.0 RJ shown on orbital diagram

Engine Thrust Relationships

• 65% output → 6.3 MN (from dialogue at 5:16)
• 100% output → 9.8 MN (from dialogue at 13:33)
• 110% output → 10.7 MN (NEW — from subtitle at 16:49, not in existing analysis)
• Thrust-output relationship is nearly linear (10.7/9.8 = 1.092 ≈ 1.1)

Other Parameters

• Mars apparent diameter 52° on rear camera (→ distance ~3,600 km at departure)
• Perijupiter countdown: 4 min 50 sec remaining
• Overshoot window: ±180 seconds
• Fuel type: D-He3 (deuterium-helium-3) cartridge system

Analysis Implications

1. V∞=12.0 km/s should be cross-referenced with our computed hyperbolic excess velocity
2. Total ΔV budget from HUD: +2.4 + |-2.3| = 4.7 km/s — compare with our analysis
3. 110% thrust capability (10.7 MN) adds a parameter not in existing EP01 analysis
4. Mars apparent diameter gives an independent distance check for departure timing
5. Navigation display confirms perijupiter at 1.5 RJ (matches dialogue "オーバー筋の木星高度は1.5RJ")

Artifacts

• ts/src/extract-frames.py: Frame extraction script with EP01 keyframe timestamps
• reports/data/episodes/ep01_onscreen_data.json: Structured on-screen parameter data
• raw_data/frames/ep01/: Extracted frame images (gitignored)
• raw_data/video/: Downloaded video (gitignored)

Notes

• Frame text resolution limited at 720p; higher resolution may reveal more HUD detail
• Automated OCR (manga-ocr, tesseract) not yet integrated — manual reading was more

accurate for this initial extraction

• Future work: extend to EP02-EP05, automate subtitle text extraction from frames