Create Video Preview

A Python script that creates video previews by extracting and combining short clips from throughout a video file, perfect for creating quick "sampler" videos to preview content.

Features

• Automatic FFmpeg Detection: Finds and lets you select from available FFmpeg installations
• Interactive Video Selection: Browse MP4 files with duration, size, and modification date information
• Customizable Preview Length: Choose clip duration (1-60 seconds) and total preview percentage (1-50%)
• Smart File Handling: Options to overwrite, skip, or rename existing output files
• High Quality Output: Uses optimized encoding settings (CRF 10, 320k audio bitrate)
• Automatic Cleanup: Removes temporary files after processing

Requirements

• Python 3.6+
• FFmpeg (automatically detected or manually specified)

Installation

1. Clone this repository:

git clone https://github.com/dataforge/create-video-preview.git
cd create-video-preview

2. Ensure FFmpeg is installed and accessible:
   • Windows: Download from ffmpeg.org or install via package manager
   • macOS: brew install ffmpeg
   • Linux: sudo apt install ffmpeg (Ubuntu/Debian) or equivalent for your distribution

Usage

Interactive Mode (Recommended)

python create_preview.py

This will:

1. Detect available FFmpeg installations
2. Show all MP4 files in the current directory with metadata
3. Let you select a video file
4. Configure clip length and preview percentage

Command Line Mode

python create_preview.py path/to/video.mp4

Example Workflow

1. Select Video: Choose from available MP4 files with duration info
2. Set Clip Length: Default 10 seconds (1-60 seconds allowed)
3. Choose Preview Percentage: Select what portion of the video to sample
   • 5% of a 60-minute video = 3 minutes of preview (18 clips at 10 seconds each)
   • 10% of a 30-minute video = 3 minutes of preview (18 clips at 10 seconds each)
4. Output: Creates [original_name] sampler.mp4

How It Works

The script extracts clips evenly distributed throughout the video:

1. Analysis: Gets video duration and calculates clip positions
2. Extraction: Creates temporary clips at calculated intervals
3. Concatenation: Combines clips into a single preview video
4. Cleanup: Removes temporary files

For example, with a 60-minute video and 10% preview:

• Total preview time: 6 minutes
• With 10-second clips: 36 clips extracted
• Clips taken every ~100 seconds throughout the video

Output Format

• Video Codec: H.264 (libx264) with CRF 10 (high quality)
• Audio Codec: AAC at 320k bitrate
• Naming: [original_filename] sampler.mp4

Error Handling

• Validates FFmpeg installation and accessibility
• Checks video file existence and readability
• Handles file conflicts with user choices (overwrite/skip/rename)
• Provides clear error messages for common issues

Technical Details

• Uses FFmpeg's -ss (seek) and -t (duration) parameters for precise clip extraction
• Creates a concat file for efficient clip combination
• Temporary files use timestamps to avoid conflicts
• Cross-platform compatibility (Windows, macOS, Linux)

Troubleshooting

FFmpeg not found:

• Ensure FFmpeg is installed and in your system PATH
• The script will search common installation directories
• You can select from multiple detected installations

Video not processing:

• Check that the video file is a valid MP4
• Ensure sufficient disk space for temporary files
• Verify the video isn't corrupted or encrypted

Output quality issues:

• The script uses high-quality settings (CRF 10)
• For smaller files, increase CRF value in the code (line 230)

License

This project is open source. Feel free to modify and distribute as needed.