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+# Core Features
+
+## 1. Frame Extraction
+- Extract from specific timecode (HH:MM:SS.ms) or frame number
+- Output format options (PNG, JPG)
+
+## 2. GPS Matching
+- Parse SRT subtitle format
+- Look up GPS at exact timecode match
+- Error handling for missing coordinates
+
+## 3. EXIF Writing
+- Overwrite GPS coordinates in extracted frames
+- Use exiftool (frames never have EXIF data)
+
+## 4. Single Frame Extraction
+- Extract one frame at specific timecode
+- Return GPS with the frame
+
+## 5. Batch Extraction
+- Walk through entire MP4 at fixed intervals (e.g., every 500ms)
+- Extract frames + match GPS at each interval
+- Support time intervals from CLI or config
+
+## 6. Batch Time List Extraction
+- Extract multiple frames at specified timecodes
+- Optionally load times from a file
+
+## Additional Features
+
+- Progress bar for long batch jobs
+- Verify frame timestamps match SRT timestamps
+- Logging/debugging mode
+- Summary report (frames extracted, GPS match rate, errors)
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