clipify

#!/bin/bash

# SPDX-FileCopyrightText: 2018 - 2024 sudorook <daemon@nullcodon.com>
#
# SPDX-License-Identifier: GPL-3.0-or-later
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the Free
# Software Foundation, either version 3 of the License, or (at your option)
# any later version.
#
# This program 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. See the GNU General Public License
# for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program. If not, see <https://www.gnu.org/licenses/>.

set -Eeuo pipefail

ROOT="$(dirname "${0}")"

source "${ROOT}"/globals

! check_command bc ffmpeg ffprobe sed && exit 3

# Global functions.
function print_usage() {
  show_header "Usage:"
  cat << EOF
  -i  --input       input video (e.g. input.mp4)"
  -o  --output      output video (e.g. output.mp4)"
  -s  --start       starting timestamp (e.g. 01:20.5)"
  -l  --length      length in seconds (e.g. 3.5)"
  -e  --end         ending timestamp (e.g. 01:20.5)"
EOF
}

function scan_input {
  local vstring
  local sstring

  fstring="$(ffprobe -probesize 1G -analyzeduration 1G -v error -show_format file:"${IN}")"
  vstring="$(ffprobe -probesize 1G -analyzeduration 1G -v error \
               -select_streams v:0 -show_streams file:"${IN}")"
  sstring="$(ffprobe -probesize 1G -analyzeduration 1G -v error \
               -select_streams s:0 -show_streams file:"${IN}")"

  if ! [[ -v VCODEC ]]; then
    VCODEC="$(echo "${vstring}" | sed -n "s/^codec_name=\(.*\)$/\1/p")"
  fi
  if ! [[ -v WIDTH ]]; then
    WIDTH="$(echo "${vstring}" | sed -n "s/^width=\(.*\)$/\1/p")"
  fi
  if ! [[ -v HEIGHT ]]; then
    HEIGHT="$(echo "${vstring}" | sed -n "s/^height=\(.*\)$/\1/p")"
  fi
  if ! [[ -v RESOLUTIONS ]]; then
    RESOLUTIONS=("native")
  fi
  if ! [[ -v DURATION ]]; then
    DURATION="$(echo "${fstring}" | sed -n "s/^duration=\(.*\)$/\1/p")"
  fi
  if ! [[ -v DIMENSIONS ]]; then
    DIMENSIONS=("${WIDTH}x${HEIGHT}")
  fi
  if ! [[ -v ASPECTRATIO ]]; then
    ASPECTRATIO="$(echo "${vstring}" | sed -n "s/^display_aspect_ratio=\(.*\)$/\1/p")"
  fi
  if ! [[ -v FPS ]]; then
    FPS="$(echo "${vstring}" | sed -n "s/^r_frame_rate=\(.*\)$/\1/p" | bc -l)"
  fi
  if ! [[ -v SCODEC ]]; then
    SCODEC="$(echo "${sstring}" | sed -n "s/^codec_name=\(.*\)$/\1/p")"
  fi
}

function make_clip {
  cmd="ffmpeg -probesize 1G -analyzeduration 1G -v info -i file:${IN@Q} -ss ${START}"
  if [[ -v LENGTH ]]; then
    cmd="${cmd} -t ${LENGTH}"
  elif [[ -v END ]]; then
    cmd="${cmd} -to ${END}"
  fi
  cmd="${cmd} -c copy -y file:${OUT@Q}"
  eval "${cmd}"
}

START=0.0

OPTIONS=i:o:s:e:l:t:
LONGOPTIONS=input:,output:,start:,end:,length:,subtitle:
PARSED=$(getopt -o "${OPTIONS}" --long "${LONGOPTIONS}" -n "${0}" -- "${@}")
eval set -- "${PARSED}"

while [ ${#} -ge 1 ]; do
  case "${1}" in
    -i | --input)
      IN="${2}"
      scan_input
      shift 2
      ;;
    -o | --output)
      OUT="${2}"
      shift 2
      ;;
    -s | --start)
      START="${2}"
      shift 2
      ;;
    -e | --end)
      END="${2}"
      shift 2
      ;;
    -l | --length)
      LENGTH="${2}"
      shift 2
      ;;
    --)
      shift
      break
      ;;
    *)
      show_error "ERROR: invalid flag ${1}."
      print_usage
      exit 3
      ;;
  esac
done

# Check if variables are set before running ffmpeg.
if ! [[ -v IN ]] || ! [[ -v OUT ]]; then
  show_error "ERROR: missing input/output files."
  print_usage
  exit 3
fi

if ! [[ -v LENGTH ]] && ! [[ -v END ]]; then
  LENGTH="$(echo "${DURATION} - ${START}" | bc -l)"
fi

make_clip