ffmpeg commands for optimized video output

ffmpeg_the_works.sh

#!/bin/bash
#
# Example usage:
# bash ffmpeg_the_works.sh PATH/TO/FILE.mp4

if ! command -v ffmpeg > /dev/null;
then
    echo "Missing ffmpeg!";
    exit 1;
fi

# --------------------------------------------------------- #
# ffmpeg_gif ()                                             #
# Converts a video with ffmpeg to a 15fps optimized gif     #
# Parameters: $source_file $target_file                     #
# Returns: target_file                                      #
# --------------------------------------------------------- #
function ffmpeg_gif() {
    palette="/tmp/palette.png"
    # filters="fps=15,scale=320:-1:flags=lanczos"
    filters="fps=15"
    ffmpeg -v warning -i "$1" -vf "$filters,palettegen" -y $palette
    ffmpeg -v warning -i "$1" -i $palette -lavfi "$filters [x]; [x][1:v] paletteuse" -y $2
}

# ---------------------------------------------------------#
# ffmpeg_the_works ()                                      #
# Converts a video to mp4, webm & gif with ffmpeg          #
# Parameters: $source_file                                 #
# Returns: $file-comp.mp4, $file-comp.webm, $file-comp.gif #
# ---------------------------------------------------------#
function ffmpeg_the_works() {

    FILENAME="${1}"
    FILENAME_NO_EXT="${FILENAME%.*}"

    ffmpeg -v warning -i "$FILENAME" -c:v libx264 -profile:v main -vf format=yuv420p -c:a aac -movflags +faststart "$2.mp4"
    printf "\nRunning ffmpeg on %s to optimize mp4\n" "$FILENAME"
    ffmpeg -v warning -i "$FILENAME" -b:v 0 -crf 25 "$FILENAME_NO_EXT-comp.mp4"

    printf "\nRunning ffmpeg on %s to optimize webm\n" "$FILENAME"
    ffmpeg -v warning -i "$FILENAME" -b:v 0 -crf 41 "$FILENAME_NO_EXT-comp.webm"

    printf "\nRunning ffmpeg_gif\n"
    ffmpeg_gif "$FILENAME" "$FILENAME_NO_EXT-comp.gif"

    printf "\n######## EXAMPLE VIDEO CODE: #########"
    printf "\n"
    printf "\n<video autoplay loop muted preload playsinline poster=\"SOME_FALLBACK_IMAGE.png\">"
    printf "\n\t<source src=\"%s-comp.webm\" type=\"video/webm\" />" "$FILENAME_NO_EXT"
    printf "\n\t<source src=\"%s-comp.mp4\" type=\"video/mp4\" />" "$FILENAME_NO_EXT"
    printf "\n\t<!--[if lt IE 9]><img src=\"%s-comp.gif\" /><![endif]-->" "$FILENAME_NO_EXT"
    printf "\n</video>"
    printf "\n"
    printf "\n######################################"
    printf "\n"
}

# run it
ffmpeg_the_works "$@"