fastermp4-withsound.bash

#!/bin/bash

set -x

SPEEDUP=1.5
while test -n "$1"
do
    yes | ffmpeg -i "$1" \
        -vf "setpts=PTS/${SPEEDUP}" \
        -c:v libx264 -preset slow -crf 23 -pix_fmt yuv420p \
        -af "atempo=${SPEEDUP}" -c:a aac -b:a 128k \
        -movflags +faststart \
        "$1".mp4 || exit 1
	shift
done

fastermp4.bash

#!/bin/bash

set -x

SPEEDUP=1.5
while test -n "$1"
do
    yes | ffmpeg -i "$1" -vf "setpts=PTS/${SPEEDUP}" -an -c:v libx264 -preset slow -crf 23 -pix_fmt yuv420p "$1".mp4 || exit 1
	shift
done