Merge MKV video files with a random OPUS audio file, creating new video files with varied background audio

go.sh

#!/bin/bash

set -euo pipefail

# Define directories
video_dir="./video"
audio_dir="./audio"

# Create an array of all opus files
mapfile -t music_files < <(find "$audio_dir" -type f -name '*.opus')

# Loop over all mkv video files in the video directory
for video_file in "$video_dir"/*/*.mkv; do
    # Select a random music file
    random_idx=$((RANDOM % ${#music_files[@]}))
    random_music="${music_files[$random_idx]}"

    # Define the output file path
    output_file="${video_file%.*}_new.mkv"

    # Log the process
    echo "Processing: $video_file with $random_music"

    # Execute ffmpeg command
    ffmpeg -i "$video_file" -i "$random_music" -map 0:v -map 1:a -c:v copy -c:a aac -shortest "$output_file" -y
done

yt-dlp.sh

yt-dlp -x \
"https://www.youtube.com/watch?v=fRg0K5rgXog&pp=ygUoQmVldGhvdmVuJ3MgU3ltcGhvbnkgTm8uIDYgKCJQYXN0b3JhbCIpIA%3D%3D" \
"https://www.youtube.com/watch?v=ea2WoUtbzuw&pp=ygUfQ2xhdWRlIERlYnVzc3kncyAiQ2xhaXIgZGUgTHVuZQ%3D%3D" \
"https://www.youtube.com/watch?v=FS6o3qFimsc&pp=ygUbRXJpayBTYXRpZSdzICJHeW1ub3DDqWRpZXMi" \
"https://www.youtube.com/watch?v=Qut5e3OfCvg" \
"https://www.youtube.com/watch?v=XOVndSdAq2Q&pp=ygUoUHlvdHIgSWx5aWNoIFRjaGFpa292c2t5J3MgIlRoZSBTZWFzb25zIg%3D%3D" \
"https://www.youtube.com/watch?v=O7YZ9FQIO-8" \
"https://www.youtube.com/watch?v=B0V24-WaYH0" \
"https://www.youtube.com/watch?v=O7YZ9FQIO-8&pp=ygUXVGNoYWlrb3Zza3kncyBzd2FuIGxha2U%3D" \
"https://www.youtube.com/watch?v=9IhmroynRtc" \
"https://www.youtube.com/watch?v=36ofZvGldnU" \
"https://www.youtube.com/watch?v=qVn2YGvIv0w"