This script uses FFMPEG to convert videos to formats compatible with various iPods based on encoding profiles described in Apple technical specifications.

ipod-video-encode.sh

t#!/bin/bash
#
# Script Name: Colin's iPod Video Encoding Tool
# Version 0.2
# Description: This script uses FFMPEG to convert videos to formats compatible with various iPods based on encoding profiles described in Apple technical specifications.
# Author: Colin Steinmann
# Contact: https://github.com/metaColin
# Date: August 29, 2023
#
# License:
# This script is provided under the following terms:
#
# - You are free to use and distribute this script in any free (non-commercial) product.
# - If you wish to use this script in a commercial or monetized product, please contact the author to obtain a license.
#
# This script is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
# Without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#

# Release Notes
# Only iPod gen 5.5 has been implemented (see TODO).
# Don't forget to 'chmod u+x ipod-video-encode.sh'
# FFMPEG must be installed/added to PATH to use this script

# Misc Notes
# Get video FPS: 'ffprobe -v error -select_streams v -of default=noprint_wrappers=1:nokey=1 -show_entries stream=r_frame_rate file.mp4' 
# AtomicParsley file.mp4 --DeepScan --iPod-uuid 1200
# Weird modification of 'atoms' was not yeielding good results
# In the end encoding with the '.m4v' file extension instead of '.mp4' made the iPod 5.5 accept H.264 video, up to 1.5 Mbps, 640 x 480 video

# References

# iPod 5.5 - Fifth Generation iPod (Late 2006) - Technical Specifications
# https://support.apple.com/kb/SP26?viewlocale=en_US&locale=en_US
# H.264 video, up to 1.5 Mbps, 640 by 480 pixels, 30 frames per sec, Baseline Low-Complexity Profile with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats
# H.264 video, up to 768 Kbps, 320 by 240 pixels, 30 frames per sec., Baseline Profile up to Level 1.3 with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats
# MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per sec., Simple Profile with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats

# Wikipedia - iPod Model Table
# https://en.wikipedia.org/wiki/IPod_Classic#Models

# Forum Posts
# https://www.reddit.com/r/ipod/comments/qnrurh/how_can_i_convert_video_for_the_ipod_5th_gen/
# https://stackoverflow.com/questions/59297824/ffmpeg-cli-set-r-30-if-input-30-fps-else-r-to-take-input-fps-if-30-fps
# https://stackoverflow.com/questions/27792934/get-video-fps-using-ffprobe
# https://www.reddit.com/r/ipod/comments/e3694n/encoding_for_video_5g_with_recent_handbrake/
# https://i.imgur.com/ORhKSGV.png
# https://www.reddit.com/r/ipod/comments/e8qevg/cant_add_any_mp4_480p_h264_videos_to_ipod_video/


# TODO
# Add subtitle default extraction/burn-in flags as an option for all encoding profiles.
# Add multi-track audio default extraction flags as an option for all encoding profiles.
# Add option to restore 4:3 video that had been pillarboxed for 16:9. (Thus returning it to it's former glory.)
# Add option to letterbox 16:9 movies into a 4:3 frame and then put the subs in the lettbox. Maybe push the video to allow for a bigger caption area.
# Implement additional iPod encoding profiles
# Implement iPod Nano encoding profiles (3rd, 4th, 5th, and 7th Generation)
# Implement iPod Touch encoding profiles  (All Generations)
# Stretch goal: Audio encoding profiles for all iPods evar!?!!

# TODO Encoding Profiles

# iPod 5.0 - Fifth Generation iPod (iPod with video) 30 GB, 60 GB - Technical Specifications
# https://support.apple.com/kb/SP41?viewlocale=en_US&locale=en_US
# H.264 video: up to 768 Kbps, 320 x 240, 30 frames per sec., Baseline Profile up to Level 1.3 with AAC-LC up to 160 Kbps, 48 Khz, stereo audio in .m4v, .mp4 and .mov file formats
# MPEG-4 video: up to 2.5 mbps, 480 x 480, 30 frames per sec., Simple Profile with AAC-LC up to 160 Kbps, 48 Khz, stereo audio in .m4v, .mp4 and .mov file formats

# iPod 6.0 - iPod classic - Technical Specifications
# https://support.apple.com/kb/SP15?viewlocale=en_US&locale=en_US
# H.264 video, up to 1.5 Mbps, 640 by 480 pixels, 30 frames per second, Low-Complexity version of the H.264 Baseline Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats
# H.264 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Baseline Profile up to Level 3.0 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats
# MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

# iPod 6.5 - iPod classic (120GB) - Technical Specifications
# https://support.apple.com/kb/SP498?viewlocale=en_US&locale=en_US
# H.264 video, up to 1.5 Mbps, 640 by 480 pixels, 30 frames per second, Low-Complexity version of the H.264 Baseline Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats
# H.264 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Baseline Profile up to Level 3.0 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats
# MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

# iPod 7.0 - iPod classic 160GB (Late 2009) - Technical Specifications
# https://support.apple.com/kb/SP572?viewlocale=en_US&locale=en_US
# H.264 video, up to 1.5 Mbps, 640 by 480 pixels, 30 frames per second, Low-Complexity version of the H.264 Baseline Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats
# H.264 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Baseline Profile up to Level 3.0 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats
# MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

echo "**************************"
echo "iPod Video Encoding Tool"
echo "**************************"
echo
echo "Select a device:"
echo "  5.0) Fifth Generation iPod"
echo "  5.5) Fifth Generation iPod (Late 2006)"
echo "  6.0) iPod classic"
echo "  6.5) iPod classic (120GB)"
echo "  7.0) iPod classic 160GB (Late 2009)"
echo
read device
echo

# Set encoding options based on the selected profile
if [[ "$device" == "5" || "$device" == "5.0" ]]; then
    echo "iPod 5.0 - Fifth Generation iPod (iPod with video) 30 GB, 60 GB"
    echo "Sorry, encoding profiles for this iPod have not been implemented yet"
    exit 1

elif [ "$device" == "5.5" ]; then
    echo "iPod 5.5 - Fifth Generation iPod (Late 2006)"
    echo
    echo "Select an encoding profile: " profile
    echo "  1) H.264 video, up to 1.5 Mbps, 640 x 480 pixels"
    echo "  2) H.264 video, up to 768 Kbps, 320 x 240 pixels"
    echo "  3) MPEG-4 video, up to 2.5 Mbps, 640 x 480 pixels"
    echo
    read profile
    echo

    if [ "$profile" == "1" ]; then
        echo "H.264 video, up to 1.5 Mbps, 640 by 480 pixels, 30 frames per sec, Baseline Low-Complexity Profile with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats"
        ffmpeg_command="ffmpeg -i \"\$input_file\" -c:v libx264 -profile:v baseline -level 2.0 -b:v 0 -maxrate 1500k -bufsize 1500k -vf \"scale=w=min(640\\,iw):h=min(480\\,ih),select='eq(n,0)+if(gt(t-prev_selected_t,1/30.50),1,0)'\" -c:a aac -b:a 160k -ar 48000 -ac 2 \"converted/\$output_file.m4v\""
    elif [ "$profile" == "2" ]; then
        echo "H.264 video, up to 768 Kbps, 320 by 240 pixels, 30 frames per sec., Baseline Profile up to Level 1.3 with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats"
        ffmpeg_command="ffmpeg -i \"\$input_file\" -c:v libx264 -profile:v baseline -level 1.3 -b:v 0 -maxrate 768k -vf \"scale=w=min(320\\,iw):h=min(240\\,ih),select='eq(n,0)+if(gt(t-prev_selected_t,1/30.50),1,0)'\" -c:a aac -b:a 160k -ar 48000 -ac 2 \"converted/\$output_file.mp4\""
    elif [ "$profile" == "3" ]; then
        echo "MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per sec., Simple Profile with AAC-LC audio up to 160 Kbps, 48 kHz, stereo audio in .m4v, .mp4, and .mov file formats"
        ffmpeg_command="ffmpeg -i \"\$input_file\" -c:v mpeg4 -b:v 0 -maxrate 2500k -vf \"scale=w=min(640\\,iw):h=min(480\\,ih),select='eq(n,0)+if(gt(t-prev_selected_t,1/30.50),1,0)'\" -c:a aac -b:a 160k -ar 48000 -ac 2 \"converted_mpeg4_640x480/\$output_file.mp4\""
    else
        echo "Invalid encoding profile selected"
        exit 1
    fi

elif [[ "$device" == "6" || "$device" == "6.0" ]]; then
    echo "iPod 6.0 - iPod classic"
    echo "Sorry, encoding profiles for this iPod have not been implemented yet"
    exit 1

elif [ "$device" == "6.5" ]; then
    echo "iPod 6.5 - iPod classic (120GB)"
    echo "Sorry, encoding profiles for this iPod have not been implemented yet"
    exit 1

elif [[ "$device" == "7" || "$device" == "7.0" ]]; then
    echo "iPod 7.0 - iPod classic 160GB (Late 2009)"
    echo "Sorry, encoding profiles for this iPod have not been implemented yet"
    exit 1

else 
    echo "Invalid device selected"
    exit 1
fi

echo
echo "You chose ipod gen $device, with encoding profile $profile"
echo
# echo "$ffmpeg_command"

# Create a subdirectory for converted files if it doesn't exist
mkdir -p converted

function batch_convert() {
    # Loop through each file in the current directory
    for input_file in *; do
        # Check if the item is a file (not a directory)
        if [ -f "$input_file" ]; then
            # Check if the file has a video extension (you can add more extensions if needed)
            if [[ "$input_file" == *.mp4 || "$input_file" == *.mkv || "$input_file" == *.avi ]]; then
                
                # Remove the file extension using parameter expansion
                output_file="${input_file%.*}"

                eval "$ffmpeg_command"

            fi
        fi
    done
}

function single_convert() {
    input_file="$1"
    output_file="${input_file%.*}"
    eval "$ffmpeg_command"
}

echo "Choose an operation:"
echo "  1) Convert a single file"
echo "  2) Batch convert all files in the current directory"
read operation

if [ "$operation" == "1" ]; then
    echo "Enter the name of the input file:"
    read input_file
    single_convert "$input_file"
elif [ "$operation" == "2" ]; then
    batch_convert
else
    echo "Invalid operation selected"
    exit 1
fi