Script to generate clip rips from a video

clip-ripper

#!/bin/bash

# clip-ripper v1.0.0
# Author: Richard Nelson [email protected]
# Description: A script to slice videos into smaller clips using FFmpeg.
# Usage: Run with required parameters to extract video segments.

VERSION="1.0.0"

# Function to display help message
usage() {
    echo ""
    echo "Clip-Ripper v$VERSION"
    echo "Usage: $0 --input-video <input_video> --length <segment_length_in_seconds> --slice-file <slice_file> [--output-dir <output_directory>] [--prefix-time <seconds>] [--separator <char>]"
    echo ""
    echo "Parameters:"
    echo "  --input-video <input_video>   Required. Path to the input video file."
    echo "  --length <seconds>            Required. Length of each segment in seconds."
    echo "  --slice-file <slice_file>     Required. File containing HH:MM:SS and tags."
    echo "  --output-dir <directory>      Optional. Directory to save sliced video files."
    echo "  --prefix-time <seconds>       Optional. Shift start time of each slice backward."
    echo "  --separator <char>            Optional. Custom field separator (default: '|')."
    echo ""
    echo "Example:"
    echo "  $0 --input-video myVideo.MOV --length 3 --slice-file slices.txt --output-dir clips --prefix-time 2 --separator '|'"
    echo ""
    exit 1
}

# Show help message if no arguments are provided or if --help is used
if [[ "$#" -eq 0 || "$1" == "--help" ]]; then
    usage
fi

# Default separator
separator="|"

# Parse command-line arguments
while [[ "$#" -gt 0 ]]; do
    case $1 in
        --input-video) input_file="$2"; shift 2;;
        --length) segment_length="$2"; shift 2;;
        --slice-file) slice_file="$2"; shift 2;;
        --output-dir) output_dir="$2"; shift 2;;
        --prefix-time) prefix_time="$2"; shift 2;;
        --separator) separator="$2"; shift 2;;
        *) echo "Unknown parameter: $1"; usage;;
    esac
done

# Validate required parameters
if [[ -z "$input_file" || -z "$segment_length" || -z "$slice_file" ]]; then
    echo "Error: Missing required parameters."
    usage
fi

# Validate input video
if [[ ! -f "$input_file" ]]; then
    echo "Error: Input video file '$input_file' does not exist."
    usage
fi

# Validate segment length
if ! [[ "$segment_length" =~ ^[0-9]+$ ]]; then
    echo "Error: Segment length must be a positive integer."
    usage
fi

# Validate slice file
if [[ ! -f "$slice_file" ]]; then
    echo "Error: Slice file '$slice_file' does not exist."
    usage
fi

# Validate prefix time (default to 0 if not set)
if [[ -z "$prefix_time" ]]; then
    prefix_time=0
elif ! [[ "$prefix_time" =~ ^[0-9]+$ ]]; then
    echo "Error: Prefix time must be a positive integer."
    usage
fi

# Validate and create output directory if specified
if [[ -n "$output_dir" ]]; then
    mkdir -p "$output_dir" || { echo "Error: Failed to create output directory '$output_dir'"; exit 1; }
else
    output_dir="."  # Default to current directory
fi

counter=1

while IFS="$separator" read -r start_time tag_info; do
    # Trim whitespace from tag_info
    tag_info=$(echo "$tag_info" | xargs)

    # Validate HH:MM:SS format using regex
    if ! [[ "$start_time" =~ ^[0-9]{2}:[0-9]{2}:[0-9]{2}$ ]]; then
        echo "Error: Invalid time format '$start_time'. Expected HH:MM:SS."
        exit 1
    fi

    # Convert start time to total seconds
    IFS=: read -r h m s <<< "$start_time"
    start_seconds=$((10#$h * 3600 + 10#$m * 60 + 10#$s))

    # Apply prefix-time shift **backwards**
    adjusted_start_seconds=$((start_seconds - prefix_time))

    # Ensure start time doesn't go negative
    if [[ "$adjusted_start_seconds" -lt 0 ]]; then
        adjusted_start_seconds=0
    fi

    # Calculate end time
    end_seconds=$((adjusted_start_seconds + segment_length))

    # Convert times back to HH:MM:SS format
    adjusted_start_time=$(printf "%02d:%02d:%02d" $((adjusted_start_seconds/3600)) $(((adjusted_start_seconds%3600)/60)) $((adjusted_start_seconds%60)))
    end_time=$(printf "%02d:%02d:%02d" $((end_seconds/3600)) $(((end_seconds%3600)/60)) $((end_seconds%60)))

    # Sanitize tag for filename (keep alphanumeric and spaces)
    if [[ -n "$tag_info" ]]; then
        safe_tag=$(echo "$tag_info" | tr -cd '[:alnum:] ')   # Keep only alphanumeric and spaces
        safe_tag=$(echo "$safe_tag" | tr ' ' '_')             # Replace spaces with underscores
        output_file="$output_dir/${input_file%.*}-slice${counter}-${safe_tag}.${input_file##*.}"
    else
        output_file="$output_dir/${input_file%.*}-slice${counter}.${input_file##*.}"
    fi

    # Generate FFmpeg command
    echo "ffmpeg -i \"$input_file\" -ss $adjusted_start_time -to $end_time -c copy \"$output_file\""
    
    counter=$((counter + 1))
done < "$slice_file"