embed-subtitles

# Embed Subtitles Burn SRT subtitles into video files using FFmpeg. ## Prerequisites **No SRT file?** Use the `transcribe` skill first to generate subtitles from audio/video. **Need translation?** After transcribing, read the SRT, translate each entry preserving timestamps, write new SRT file. No API needed. ## Quick Start ```bash cd ~/.claude/skills/embed-subtitles/scripts # Burn SRT into video npx ts-node embed-subtitles.ts -i video.mp4 -s subtitles.srt -o output.mp4 # Custom styling npx ts-node embed-subtitles.ts -i video.mp4 -s subtitles.srt -o output.mp4 \ --font-size 24 --position bottom --margin 40 # Add credit text overlay at end npx ts-node embed-subtitles.ts -i video.mp4 -s subtitles.srt -o output.mp4 \ --credit "Your Name" --credit-position top ``` ## Options | Option | Short | Default | Description | |--------|-------|---------|-------------| | `--input` | `-i` | (required) | Input video file | | `--subtitles` | `-s` | (required) | SRT subtitle file | | `--output` | `-o` | (required) | Output video file | | `--font-size` | | 20 | Font size in pixels | | `--font-name` | | Arial | Font family name | | `--position` | | bottom | Subtitle position: top, center, bottom | | `--margin` | | 25 | Margin from edge in pixels | | `--color` | | white | Text color | | `--outline` | | 2 | Outline thickness | | `--shadow` | | 1 | Shadow depth | | `--credit` | | | Credit text to show at end | | `--credit-position` | | top | Credit position: top, bottom | | `--credit-duration` | | 2.5 | Credit display duration in seconds | | `--extract-frame` | | | Extract frame at specified second for verification | ## Position Values - `top` - Near top of video (good for credits, avoids bottom burned-in text) - `center` - Middle of video - `bottom` - Near bottom of video (traditional subtitle position) ## Dependencies - FFmpeg (must be installed and in PATH) ## RTL Auto-Detection & Fix (CRITICAL) **Before embedding ANY SRT file, Claude MUST check if the content is RTL.** ### Detection Read the SRT file and check if the majority of text lines contain Hebrew/Arabic/Farsi characters: - Hebrew range: `\u0590-\u05FF` - Arabic range: `\u0600-\u06FF` - Farsi additional: `\u0750-\u077F` If RTL content is detected, apply the fix BEFORE passing to FFmpeg. ### RTL Fix Wrap each text line (not index numbers, not timestamps) with Unicode directional marks: ```python python3 -c " import re with open('SRT_FILE_PATH', 'r', encoding='utf-8') as f: content = f.read() lines = content.split('\n') result = [] for line in lines: stripped = line.strip() if stripped and not re.match(r'^\d+$', stripped) and not re.match(r'\d{2}:\d{2}:\d{2}', stripped): line = '\u202B' + line + '\u202C' result.append(line) with open('SRT_FILE_PATH', 'w', encoding='utf-8') as f: f.write('\n'.join(result)) " ``` - **U+202B** (RLE - Right-to-Left Embedding): forces RTL paragraph direction - **U+202C** (PDF - Pop Directional Formatting): closes the embedding **This fixes:** English words at line start, periods/commas on wrong side, mixed bidi text. ### When to apply Claude should analyze the SRT content intelligently: - If most text is Hebrew/Arabic/Farsi → apply RTL fix - If mixed but predominantly RTL → apply RTL fix - If LTR (English, Spanish, etc.) → skip - No flag needed from the user - detect automatically ## Notes - For Arabic credits, use English text due to FFmpeg drawtext RTL limitations - Use `--extract-frame` to verify subtitle positioning before final render