{ ... }: {
	text = ''
		# Convert between different formats.
		# By default tries to convert all files.
		# Usage: transcode <FORMAT> [FILES]
		function transcode() { local IFS=$'\n'
			local format=''${1}
			local targets=(''${@:2})
			[[ "''${targets}" = "" ]] && targets=($(_ls_file))

			# Report no format.
			if [[ "''${format}" = "" ]] || [[ "''${format}" =~ "." ]]; then
				_error "No format specified."
				help transcode
				return 2
			fi

			process() {
				# Define context names and status.
				local from="''${target##*.}"
				local to="''${format}"
				local output="''${target##*/}"
				output="''${output%.*}.''${to}"

				# Skip if file exists.
				[[ -f "''${output}" ]] && { _iterate_skip "Already exists."; return 0; }

				# Support multiple inputs.
				[[ "''${to}" = "flac" ]] && from=""
				[[ "''${to}" = "jxl"  ]] && from=""
				[[ "''${to}" = "mka"  ]] && from=""
				[[ "''${to}" = "mkv"  ]] && from=""
				[[ "''${to}" = "mp3"  ]] && from=""

				# Send convert.
				case "''${from}-''${to}" in
					"gz-xz"|"tgz-txz")
						_transcode_gz-xz "''${target}" "''${output}"
						;;
					"xz-gz"|"txz-tgz")
						_transcode_xz-gz "''${target}" "''${output}"
						;;
					"-mp3")
						_transcode_mp3 "''${target}" "''${output}"
						;;
					"-flac")
						_transcode_flac "''${target}" "''${output}"
						;;
					"-mka")
						_transcode_mka "''${target}" "''${output}"
						;;
					"-mkv")
						_transcode_mkv "''${target}" "''${output}"
						;;
					"-jxl")
						_transcode_jxl "''${target}" "''${output}"
						;;
					*)
						_error "Conversion ''${target##*.}-''${to} not supported."
						return 1
						;;
				esac
			}

			_iterate_targets process ''${targets[@]}
		}

		function _transcode_gz-xz() {
			[[ -f "''${2}" ]] && return 1
			pv "''${1}" | gzip -d | xz -9e > "''${2}"
		}

		function _transcode_xz-gz() {
			[[ -f "''${2}" ]] && return 1
			pv "''${1}" | xz -d | gzip -1 > "''${2}"
		}

		function _transcode_mp3() {
			ffmpeg -n -i "''${1}" -c:a libmp3lame -b:a 320k -f mp3 "''${2}"
		}

		function _transcode_flac() {
			ffmpeg -n -i "''${1}" -c:a flac -f flac "''${2}"
		}

		function _transcode_mka() {
			local braudio=$(_ffprobe_ba "''${1}")
			[[ ''${braudio} -gt 128 ]] && braudio=128

			ffmpeg -n -i "''${1}" -ac 2 -c:a libopus -b:a ''${braudio}k -vn "''${2}"
		}

		function _transcode_mkv() {
			local keyint=$(_ffprobe_keyint "''${1}")
			local braudio=$(_ffprobe_ba "''${1}")
			local fps=$(_ffprobe_fps "''${1}")
			[[ ''${braudio} -gt 128 ]] && braudio=128
			[[ ''${fps} -gt 30 ]] && fps=30

			# ffmpeg -n -i "''${1}" -c:a libopus -b:a ''${braudio}k -c:v libsvtav1 -crf 30 -svtav1-params "fast-decode=1:tune=0" -preset 8 -pix_fmt yuv420p10le -g ''${keyint} -vf "scale=-2:min'(1080,ih)'" "''${2}"
			ffmpeg -n -i "''${1}" -map 0 -map -v -map V -map -t -dn -c:s srt -ac 2 -c:a libopus -b:a ''${braudio}k -c:v libsvtav1 -crf 30 -svtav1-params "tune=0" -pix_fmt yuv420p10le -g ''${keyint} -vf "scale=-2:min'(1080,ih)' , fps=''${fps}" "''${2}"
		}

		function _transcode_jxl() {
			cjxl -e 10 --lossless_jpeg=1 -- "''${1}" "''${2}"
		}
	'';
}