ffsubshot

#!/usr/bin/env bash

# ffsubshot: Take a screenshot at the given timestamp, with subtitles.

set -eo pipefail

# By default, assume subtitles are baked into the input.
# Users can override this to use an external subtitle file.
SUB_FILE="${SUB_FILE:-${1}}"

function help {
  echo "Usage: ffsubshot <input> <timestamp> <output>"
  exit
}

function installed {
    cmd=$(command -v "${1}")

    [[ -n "${cmd}" ]] && [[ -f "${cmd}" ]]
    return ${?}
}

[[ $# -eq 3 && -f $1 && -n $2 && ! -f $3 ]] || help
installed ffmpeg || { >&2 echo "Missing ffmpeg."; exit 1; }

ffmpeg -ss "${2}" -copyts \
  -i "${1}" -vf subtitles="${SUB_FILE}" \
  -vframes 1 "${3}"