Convert any movie to WebM (AV1/Opus/WebVTT)

ffmpeg.sh

#!/usr/bin/env bash

set -o errexit
set -o nounset
set -o pipefail
shopt -s inherit_errexit

# e.g. "Movie name (Year)" or "Series name (Year) - S01E01 - Episode title"
TITLE="${TITLE:-}"
DESCRIPTION="${DESCRIPTION:-}"
INPUT="${INPUT:-}"
OUTPUT="${OUTPUT:-}"
OVERWRITE="${OVERWRITE:-0}"
EXTERNAL_SUB="${EXTERNAL_SUB:-1}"
PRESET="${PRESET:-6}"
CRF="${CRF:-30}"
PRESET_INTERVAL="${PRESET_INTERVAL:-"-1"}"
CRF_INTERVAL="${CRF_INTERVAL:-"-5"}"
PRESET_MAX="${PRESET_MAX:-${PRESET}}"
PRESET_MIN="${PRESET_MIN:-${PRESET}}"
CRF_MAX="${CRF_MAX:-${CRF}}"
CRF_MIN="${CRF_MIN:-${CRF}}"
PIX_FMT="${PIX_FMT:-yuv420p10le}"
KEYINT_SEC="${KEYINT_SEC:-5}"
SS="${SS:-}"
TO="${TO:-}"
MAX_RES="${MAX_RES:-}"

if test -z "${INPUT}" || test -z "${OUTPUT}"
then
	echo "You need to set the INPUT & OUTPUT environment variable"
	exit 1
fi

if test "${OUTPUT##*.}" == "webm"
then
	EXTENSION="webm"
else
	EXTENSION="mkv"
fi

if test "${OVERWRITE}" -eq 1
then
	OVERWRITE="-y"
else
	OVERWRITE="-n"
fi

PARAMS=()
FFPROBE="$(ffprobe -loglevel warning -print_format json -show_format -show_streams "${INPUT}")"

if test -z "${FFPROBE}"
then
	echo "ffprobe..."
	exit 1
fi

if test -n "${SS}"
then
	PARAMS+=(-ss "${SS}")
fi

if test -n "${TO}"
then
	PARAMS+=(-to "${TO}")
fi

if test -n "${MAX_RES}"
then
	FFPROBE_VIDEO_WIDTH="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].width // ""')"
	FFPROBE_VIDEO_HEIGHT="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].height // ""')"
	VIDEO_DIM_DIFF="$(echo "${FFPROBE_VIDEO_WIDTH} ${FFPROBE_VIDEO_HEIGHT}" | awk '{ printf "%.3f\n", $1/$2 }')"
	MAX_RES_WIDTH="${MAX_RES%x*}"
	MAX_RES_HEIGHT="${MAX_RES#*x}"
	SCALE_WIDTH="min(${MAX_RES_WIDTH},iw):-2"
	SCALE_HEIGHT="-2:min(${MAX_RES_HEIGHT},ih)"

	if test -z "${MAX_RES_WIDTH}" && test -z "${MAX_RES_HEIGHT}"
	then
		SCALE=""
	elif test -n "${MAX_RES_WIDTH}" && test -z "${MAX_RES_HEIGHT}"
	then
		SCALE="${SCALE_WIDTH}"
	elif test -z "${MAX_RES_WIDTH}" && test -n "${MAX_RES_HEIGHT}"
	then
		SCALE="${SCALE_HEIGHT}"
	else
		MAX_RES_DIFF="$(echo "${MAX_RES_WIDTH} ${MAX_RES_HEIGHT}" | awk '{ printf "%.3f\n", $1/$2 }')"

		if $(echo "${VIDEO_DIM_DIFF} ${MAX_RES_DIFF}" | awk '{ exit !( $1 > $2 ) }')
		then
			SCALE="${SCALE_WIDTH}"
		elif $(echo "${VIDEO_DIM_DIFF} ${MAX_RES_DIFF}" | awk '{ exit !( $1 < $2 ) }')
		then
			SCALE="${SCALE_HEIGHT}"
		else
			SCALE=""
		fi
	fi

	if test -n "${SCALE}"
	then
		PARAMS+=(-filter:v:0 scale="'${SCALE}'")
	fi
fi

FFPROBE_VIDEO_FRAME_RATE="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].r_frame_rate // ""')"
if test -n "${FFPROBE_VIDEO_FRAME_RATE}"
then
	KEYINT="$(echo "${KEYINT_SEC}*${FFPROBE_VIDEO_FRAME_RATE}" | awk -F '[*/]' '{ printf "%.0f\n", $1*$2/$3 }')"
else
	KEYINT="120"
fi

FFPROBE_VIDEO_COLOR_RANGE="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].color_range // ""')"
FFPROBE_VIDEO_COLOR_SPACE="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].color_space // ""')"
FFPROBE_VIDEO_COLOR_TRANSFER="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].color_transfer // ""')"
FFPROBE_VIDEO_COLOR_PRIMARIES="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "video")] | .[0].color_primaries // ""')"

COLOR_RANGE="${FFPROBE_VIDEO_COLOR_RANGE:-tv}"
COLOR_SPACE="${FFPROBE_VIDEO_COLOR_SPACE:-bt709}"
COLOR_TRANSFER="${FFPROBE_VIDEO_COLOR_TRANSFER:-bt709}"
COLOR_PRIMARIES="${FFPROBE_VIDEO_COLOR_PRIMARIES:-bt709}"

FFPROBE_AUDIO_CHANNELS="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "audio")] | .[0].channels // ""')"
if test -n "${FFPROBE_AUDIO_CHANNELS}"
then
	BITRATE_AUDIO="$(echo "64*${FFPROBE_AUDIO_CHANNELS}" | awk -F '*' '{ printf "%.0f\n", $1*$2 }')K"
else
	BITRATE_AUDIO="128K"
fi

FFPROBE_AUDIO_CHANNEL_LAYOUT="$(echo "${FFPROBE}" | jq -r '[.streams[] | select(.codec_type == "audio")] | .[0].channel_layout // ""')"
if test -n "${FFPROBE_AUDIO_CHANNEL_LAYOUT}" && test "${FFPROBE_AUDIO_CHANNEL_LAYOUT}" != "stereo" && test "${FFPROBE_AUDIO_CHANNEL_LAYOUT}" != "mono"
then
	MAPPING_FAMILY="1"
	CHANNEL_LAYOUTS="7.1|6.1|5.1|5.0|quad|3.0"
else
	MAPPING_FAMILY="0"
	CHANNEL_LAYOUTS="stereo|mono"
fi

for PRESET in $(seq ${PRESET_MAX} ${PRESET_INTERVAL} ${PRESET_MIN})
do
	for CRF in $(seq ${CRF_MAX} ${CRF_INTERVAL} ${CRF_MIN})
	do
		INFO=""
		if test "${PRESET_MAX}" -ne "${PRESET_MIN}"
		then
			INFO="${INFO}.pre${PRESET}"
		fi

		if test "${CRF_MAX}" -ne "${CRF_MIN}"
		then
			INFO="${INFO}.crf${CRF}"
		fi

		if test "${EXTERNAL_SUB}" -eq 1
		then
			ffmpeg \
				-benchmark \
				-probesize 9223372036854775807 \
				-analyzeduration 9223372036854775807 \
				-fflags +genpts+igndts \
				-i "${INPUT}" \
				-map "0:s:0?" -c:s:0 webvtt \
				"${PARAMS[@]}" "${OVERWRITE}" \
				"${OUTPUT%.*}${INFO}.en.vtt" || true
		fi

		set -x
		ffmpeg \
			-benchmark \
			-probesize 9223372036854775807 \
			-analyzeduration 9223372036854775807 \
			-fflags +genpts+igndts \
			-i "${INPUT}" \
			-map "0:v:0?" \
			-c:v:0 libsvtav1 \
			-preset:v:0 "${PRESET}" \
			-crf:v:0 "${CRF}" \
			-pix_fmt:v:0 "${PIX_FMT}" \
			-color_primaries:v:0 "${COLOR_PRIMARIES}" \
			-color_trc:v:0 "${COLOR_TRANSFER}" \
			-colorspace:v:0 "${COLOR_SPACE}" \
			-color_range:v:0 "${COLOR_RANGE}" \
			-svtav1-params:v:0 enable-overlays=1:enable-tf=0:fast-decode=0:film-grain=0:film-grain-denoise=0:keyint="${KEYINT}":scd=1:tune=0 \
			-map "0:a:0?" \
			-c:a:0 libopus \
			-b:a:0 "${BITRATE_AUDIO}" \
			-vbr:a:0 on \
			-mapping_family:a:0 "${MAPPING_FAMILY}" \
			-filter:a:0 aformat=channel_layouts="${CHANNEL_LAYOUTS}" \
			-map "0:s:0?" \
			-c:s:0 webvtt \
			-map_chapters -1 \
			-map_metadata -1 \
			-metadata:g title="${TITLE}" \
			-metadata:g description="${DESCRIPTION}" \
			-metadata:s:v:0 language="" \
			-metadata:s:v:0 title="" \
			-metadata:s:a:0 language="eng" \
			-metadata:s:a:0 title="English" \
			-metadata:s:s:0 language="eng" \
			-metadata:s:s:0 title="English" \
			-disposition:v:0 default \
			-disposition:a:0 default \
			-disposition:s:0 default \
			"${PARAMS[@]}" "${OVERWRITE}" \
			"${OUTPUT%.*}${INFO}.${EXTENSION#.}"
		set +x
	done
done