Batch caption videos with subtitles

Batch captioning videos with subtitles involves generating subtitle files (like .srt or .vtt) for multiple videos at once. Here’s a streamlined process to do this efficiently using tools like FFmpeg, Whisper by OpenAI, or third-party software. Below are methods you can use depending on your preference for command-line tools or GUI software.

Method 1: Using Whisper (OpenAI’s ASR model) for Batch Subtitle Generation

Requirements

• Python installed

• Whisper by OpenAI

• FFmpeg

Installation

bash
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pip install git+https://github.com/openai/whisper.git 
pip install ffmpeg-python

Batch Script (Python Example)

python
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import os
import whisper

model = whisper.load_model("base")  # You can use "tiny", "small", "medium", or "large"
input_folder = "videos"
output_folder = "subtitles"

os.makedirs(output_folder, exist_ok=True)

for filename in os.listdir(input_folder):
    if filename.endswith((".mp4", ".mkv", ".avi", ".mov")):
        video_path = os.path.join(input_folder, filename)
        print(f"Transcribing {filename}...")
        result = model.transcribe(video_path)
        srt_path = os.path.join(output_folder, f"{os.path.splitext(filename)[0]}.srt")
        with open(srt_path, "w", encoding="utf-8") as f:
            f.write(result["srt"])
        print(f"Saved subtitles to {srt_path}")

To Burn Subtitles (Optional)

bash
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ffmpeg -i input.mp4 -vf subtitles=subtitles/input.srt output.mp4

Method 2: Using AutoSub (Open Source Alternative)

Installation

bash
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pip install git+https://github.com/agermanidis/autosub.git

Batch Script

bash
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for file in *.mp4; do
    autosub "$file"
done

This will generate .srt subtitle files for each video in the current directory.

Method 3: Use a GUI Tool (for non-programmers)

Recommended Tools

1. Kapwing – Upload videos and auto-generate captions.

2. Subtitle Edit – Import video/audio and auto-generate subtitles using Google or Whisper ASR.

3. Jubler + MPlayer – Good for manual editing in batch jobs.

Tips for SEO-Optimized Subtitles

• Use clear punctuation and accurate timestamps.

• Include keywords naturally within the dialogue.

• Save subtitles in .srt format for YouTube or .vtt for HTML5 use.

• Ensure filenames match video titles for better video SEO indexing.

Batch Automation with FFmpeg + Whisper

You can integrate Whisper transcription and FFmpeg subtitle burning in a shell script or Python automation pipeline to process entire folders of videos automatically.

Let me know if you want a ready-to-use automation script tailored for a specific OS (Windows, macOS, Linux) or subtitle format (e.g., .srt, .vtt).