README

Overview

This repository contains a single bash script designed to download, trim, and convert videos from a provided URL using yt-dlp and ffmpeg. The script automates the process of downloading a video, removing portions from the beginning and/or end, and exporting the result as a high-quality MP4 file.

Prerequisites

Before running the script, ensure you have the following dependencies installed:

yt-dlp: A command-line program to download videos from YouTube and other websites.
- yt-dlp GitHub
ffmpeg: A powerful tool to record, convert, and stream audio and video.
- FFmpeg Official Website

On a Linux system, you can install these using:

sudo apt-get install yt-dlp ffmpeg

Usage

To use this script, follow the steps below:

Make the script executable (if not already):
```
chmod +x <script-name>.sh
```
Run the script:
```
./<script-name>.sh
```
The script will prompt for the following inputs:
- Video URL: Provide the URL of the video you want to download.
- Output file name: Specify the name of the output file (without the .mp4 extension).
- Seconds to trim from the beginning: Optionally, specify how many seconds to trim from the start of the video (default is 0).
- Seconds to trim from the end: Optionally, specify how many seconds to trim from the end of the video (default is 0).
The script will:
- Download the video in the highest available quality using yt-dlp.
- Use ffmpeg to trim the specified portions from the video.
- Save the output in the desired MP4 format with h.264 video encoding, AAC audio encoding, and specific bitrate settings.
- Delete the original downloaded file to save space.

Example Workflow

$ ./download_trim_convert.sh
Enter the video URL: https://www.example.com/video
Downloading video...
Enter the output file name (e.g., output_4k2): my_video
Enter seconds to trim from the beginning (default is 0): 5
Enter seconds to trim from the end (default is 0): 10

This example would download the video, trim 5 seconds from the start and 10 seconds from the end, then output it as my_video.mp4.

Script Breakdown

Download the video: The script uses yt-dlp to download the best available quality video and audio combination into a file named input.<extension>.
Video Trimming:
- Prompts for user input to determine how many seconds to trim from the beginning and end of the video.
- Extracts the video's total duration using ffmpeg and calculates the new end time.
Conversion:
- Uses ffmpeg to encode the video using h.264 and AAC codecs, with a video bitrate of 18M, and outputs the video at 30 frames per second in an .mp4 container.
Cleanup: The original downloaded file is deleted after processing to avoid unnecessary disk usage.

Notes

The script assumes the video URL is valid and that the desired output file ends with .mp4.
It uses h264_videotoolbox for video encoding, which works efficiently on Apple hardware. If you are running this script on other platforms, you might need to adjust the codec (-c:v option).

License

This project is provided as-is without any explicit license. You are free to use, modify, and distribute it as needed.

d-meagher/video-compress