Hard-burned subtitles OCR to SRT extractor

• Apple Silicon M1/M2 toolchain for extracting .SRT subtitles from movies with embedded hard-burned subtitles
• the OCR step is using a modified version of macOCR (forked from https://github.com/xulihang/macOCR); the macos Apple Silicon ARM64 binary is included in the repo as OCR

The workflow sequence run by the do-all.sh script:

1. Generate cropped video with ffmpeg (you'll have to adjust the crop area for your video size)
2. Generate PNG snapshots (using ffmpeg ... fps=1 — 1 snapshot per second)
3. Optical Character Recognition using macOCR (Apple Silicon only) outputs JSON file.
4. Convert JSON to SRT + normalize and deduplicate using https://github.com/cdown/srt.

NOTE

• this collection of scripts is work in progress and will require tweaking for each specific scenario (the corresponding places that need editing are marked with TODO comments in the code); use at your own risk