Subtitle Time Shift Script

This is a Python script designed to help you adjust the timing of subtitles in .srt files. Whether you need to fix sync issues or simply shift the timing, this script will allow you to add or subtract time to all subtitle timestamps in the file.

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Features

• Adjust subtitle times by any given amount of seconds.
• Supports HH:MM:SS,SSS format commonly used in .srt subtitle files.
• Creates a new adjusted subtitle file with the same content but with updated timings.

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Installation

No installation is required, just make sure you have Python installed (version 3.x recommended).

1. Clone the repository or download the script.
2. Ensure your subtitle file is in .srt format and accessible.

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Usage

1. Download the subtitle_time_shift.py script and place it in the same folder as your .srt subtitle file, or specify the full path to the subtitle file.
2. Open your terminal/command prompt and run the script:

python subtitle_time_shift.py

3. When prompted, enter the number of seconds you want to shift the subtitle times by:
   • Positive number to increase the timestamp (delay subtitles).
   • Negative number to decrease the timestamp (advance subtitles).

Example input:

Enter the number of seconds to increase the timestamps: 2.5

4. The script will read your subtitle file, adjust the timestamps, and create a new file with _adj appended to the original filename. For example, if your file was movie.srt, the adjusted file will be named movie.srt_adj.

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Example

Given a subtitle line like:

00:01:23,500 --> 00:01:25,000
Hello, how are you?

If you input 2 seconds to shift, the adjusted subtitle will be:

00:01:25,500 --> 00:01:27,000
Hello, how are you?

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Code Walkthrough

• convert_to_seconds(time_str): Converts a subtitle timestamp from HH:MM:SS,SSS format to total seconds (including milliseconds).

• convert_to_timestamp(seconds): Converts seconds back into the HH:MM:SS,SSS format.

• adjust_subtitles(file_path, time_shift_seconds): Reads the .srt file, identifies all timestamps using regex, and applies the time shift. Then, it writes the adjusted subtitles to a new file.

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Requirements

• Python 3.x
• No external dependencies (uses built-in Python libraries like re).