ffmpeg.sh

ffmpeg.sh

#!/bin/zsh

main() {
    local file="$1"
    local filename="${file:t}"
    local filestem="${file:t:r}"
    local filedir="${file:h}"
    local safe_name="${filename//\"/\\\"}"

    # ───── probe video info ─────────────────────
    local SRC_HEIGHT
    SRC_HEIGHT=$(ffprobe -v error -select_streams v:0 -show_entries stream=height \
        -of default=nokey=1:noprint_wrappers=1 "$file")

    local SRC_FPS_RAW
    SRC_FPS_RAW=$(ffprobe -v error -select_streams v:0 -show_entries stream=r_frame_rate \
        -of default=nokey=1:noprint_wrappers=1 "$file")

    local FPS_NUM=${SRC_FPS_RAW%%/*}
    local FPS_DEN=${SRC_FPS_RAW##*/}
    [[ "$FPS_DEN" == "$SRC_FPS_RAW" ]] && FPS_DEN=1
    local SRC_FPS=$(( (FPS_NUM + FPS_DEN / 2) / FPS_DEN ))

    local SRC_DUR_RAW
    SRC_DUR_RAW=$(ffprobe -v error -show_entries format=duration \
        -of default=nokey=1:noprint_wrappers=1 "$file")
    local SRC_DUR_SEC=${SRC_DUR_RAW%%.*}

    local SRC_AUDIO_KBPS=128
    local audio_br
    audio_br=$(ffprobe -v error -select_streams a:0 -show_entries stream=bit_rate \
        -of default=nokey=1:noprint_wrappers=1 "$file" 2>/dev/null)
    [[ -n "$audio_br" && "$audio_br" != "N/A" ]] && SRC_AUDIO_KBPS=$(( audio_br / 1000 ))

    echo " Probed: ${SRC_HEIGHT}p / ${SRC_FPS}fps / ${SRC_DUR_SEC}s"

    # ───── build resolution choices ─────────────
    local -a res_items=()
    local res_default="keep"
    for r in 2160 1440 1080 720; do
        (( r <= SRC_HEIGHT )) && res_items+=("${r}p")
        (( r == SRC_HEIGHT )) && res_default="${r}p"
    done
    [[ "$res_default" == "keep" ]] && res_items+=("keep")

    local res_as_list=""
    for item in "${res_items[@]}"; do
        [[ -n "$res_as_list" ]] && res_as_list+=", "
        res_as_list+="\"$item\""
    done

    local CHOSEN_RES
    CHOSEN_RES=$(osascript -e "choose from list {${res_as_list}} with prompt \"Resolution (source: ${SRC_HEIGHT}p)\" default items {\"${res_default}\"} with title \"FFmpeg - ${safe_name}\"")
    [[ "$CHOSEN_RES" == "false" ]] && echo " Cancelled." && return

    # ───── build FPS choices ────────────────────
    local -a fps_items=()
    local fps_default="keep"
    for fp in 240 120 60 30 24; do
        (( fp <= SRC_FPS )) && fps_items+=("${fp}fps")
        (( fp == SRC_FPS )) && fps_default="${fp}fps"
    done
    [[ "$fps_default" == "keep" ]] && fps_items+=("keep")

    local fps_as_list=""
    for item in "${fps_items[@]}"; do
        [[ -n "$fps_as_list" ]] && fps_as_list+=", "
        fps_as_list+="\"$item\""
    done

    local CHOSEN_FPS
    CHOSEN_FPS=$(osascript -e "choose from list {${fps_as_list}} with prompt \"FPS (source: ${SRC_FPS}fps)\" default items {\"${fps_default}\"} with title \"FFmpeg - ${safe_name}\"")
    [[ "$CHOSEN_FPS" == "false" ]] && echo " Cancelled." && return

    # ───── Codec ────────────────────────────────
    local CHOSEN_CODEC_LABEL
    CHOSEN_CODEC_LABEL=$(osascript -e "choose from list {\"H.264 (libx264)\", \"H.265 (libx265)\"} with prompt \"Codec\" default items {\"H.264 (libx264)\"} with title \"FFmpeg - ${safe_name}\"")
    [[ "$CHOSEN_CODEC_LABEL" == "false" ]] && echo " Cancelled." && return

    # ───── CRF ──────────────────────────────────
    local crf_result
    crf_result=$(osascript -e "display dialog \"CRF (default 23)\" default answer \"23\" with title \"FFmpeg - ${safe_name}\" buttons {\"Cancel\", \"OK\"} default button \"OK\"" 2>/dev/null) || { echo " Cancelled."; return; }
    local CHOSEN_CRF="${crf_result##*text returned:}"
    [[ -z "$CHOSEN_CRF" ]] && CHOSEN_CRF="23"

    # ───── Dedup ────────────────────────────────
    local CHOSEN_DEDUP
    CHOSEN_DEDUP=$(osascript -e "choose from list {\"None\", \"Dedup (CFR, shorter)\", \"Dedup (VFR)\"} with prompt \"Dedup frames\" default items {\"None\"} with title \"FFmpeg - ${safe_name}\"")
    [[ "$CHOSEN_DEDUP" == "false" ]] && echo " Cancelled." && return

    # ───── Audio ────────────────────────────────
    local CHOSEN_AUDIO_LABEL
    CHOSEN_AUDIO_LABEL=$(osascript -e "choose from list {\"Keep audio\", \"Remove audio\"} with prompt \"Audio\" default items {\"Keep audio\"} with title \"FFmpeg - ${safe_name}\"")
    [[ "$CHOSEN_AUDIO_LABEL" == "false" ]] && echo " Cancelled." && return

    # ───── Target MB ────────────────────────────
    local target_result
    target_result=$(osascript -e "display dialog \"Target file size in MB (leave empty to skip)\" default answer \"\" with title \"FFmpeg - ${safe_name}\" buttons {\"Cancel\", \"OK\"} default button \"OK\"" 2>/dev/null) || { echo " Cancelled."; return; }
    local TARGET_MB="${target_result##*text returned:}"
    [[ -z "$TARGET_MB" ]] && TARGET_MB="0"

    # ───── parse selections ─────────────────────
    [[ "$CHOSEN_RES" != "keep" ]] && CHOSEN_RES="${CHOSEN_RES%p}"
    [[ "$CHOSEN_FPS" != "keep" ]] && CHOSEN_FPS="${CHOSEN_FPS%fps}"

    local CHOSEN_CODEC="libx264"
    [[ "$CHOSEN_CODEC_LABEL" == *"libx265"* ]] && CHOSEN_CODEC="libx265"

    local DEDUP_MODE="none"
    [[ "$CHOSEN_DEDUP" == *"CFR"* ]] && DEDUP_MODE="cfr"
    [[ "$CHOSEN_DEDUP" == *"VFR"* ]] && DEDUP_MODE="vfr"

    local AUDIO_IDX=0
    [[ "$CHOSEN_AUDIO_LABEL" == *"Remove"* ]] && AUDIO_IDX=1

    # ───── build ffmpeg arguments ───────────────
    local -a ffargs=(-i "$file" -c:v "$CHOSEN_CODEC")
    [[ "$CHOSEN_CODEC" == "libx265" ]] && ffargs+=(-tag:v hvc1)
    ffargs+=(-crf "$CHOSEN_CRF")

    # maxrate cap
    local MAXRATE=0 BUFSIZE=0
    if [[ "$TARGET_MB" != "0" ]]; then
        local AUDIO_COST=$SRC_AUDIO_KBPS
        (( AUDIO_IDX == 1 )) && AUDIO_COST=0
        local TOTAL_KBPS=$(( TARGET_MB * 8192 / SRC_DUR_SEC ))
        local VIDEO_KBPS=$(( TOTAL_KBPS - AUDIO_COST ))
        (( VIDEO_KBPS <= 0 )) && VIDEO_KBPS=100
        MAXRATE=$(( VIDEO_KBPS * 3 / 2 ))
        BUFSIZE=$(( MAXRATE * 2 ))
        ffargs+=(-maxrate "${MAXRATE}k" -bufsize "${BUFSIZE}k")
    fi

    # video filters
    local VF_CHAIN=""
    [[ "$DEDUP_MODE" == "cfr" ]] && VF_CHAIN="mpdecimate=hi=300:lo=300:frac=1:max=0,setpts=N/FRAME_RATE/TB"
    [[ "$DEDUP_MODE" == "vfr" ]] && VF_CHAIN="mpdecimate=hi=300:lo=300:frac=1:max=0"
    if [[ "$CHOSEN_RES" != "keep" ]]; then
        [[ -z "$VF_CHAIN" ]] && VF_CHAIN="scale=-2:${CHOSEN_RES}" || VF_CHAIN="${VF_CHAIN},scale=-2:${CHOSEN_RES}"
    fi
    [[ -n "$VF_CHAIN" ]] && ffargs+=(-vf "$VF_CHAIN")

    [[ "$CHOSEN_FPS" != "keep" ]] && ffargs+=(-r "$CHOSEN_FPS")
    [[ "$DEDUP_MODE" == "vfr" ]] && ffargs+=(-vsync vfr)

    if (( AUDIO_IDX == 1 )); then
        ffargs+=(-an)
    else
        ffargs+=(-c:a copy)
    fi

    # ───── build output filename suffix ─────────
    local SUFFIX=""
    [[ "$CHOSEN_RES" != "keep" ]] && SUFFIX="${SUFFIX}_${CHOSEN_RES}p"
    [[ "$CHOSEN_FPS" != "keep" ]] && SUFFIX="${SUFFIX}_${CHOSEN_FPS}fps"
    [[ "$CHOSEN_CODEC" == "libx265" ]] && SUFFIX="${SUFFIX}_h265"
    [[ "$CHOSEN_CRF" != "23" ]] && SUFFIX="${SUFFIX}_crf${CHOSEN_CRF}"
    [[ "$DEDUP_MODE" != "none" ]] && SUFFIX="${SUFFIX}_dedup"
    [[ "$DEDUP_MODE" == "vfr" ]] && SUFFIX="${SUFFIX}-vfr"
    (( AUDIO_IDX == 1 )) && SUFFIX="${SUFFIX}_noaudio"
    [[ "$TARGET_MB" != "0" ]] && SUFFIX="${SUFFIX}_${TARGET_MB}mb"
    [[ -z "$SUFFIX" ]] && SUFFIX="_transcoded"

    local OUTPUT="${filedir}/${filestem}${SUFFIX}.mp4"
    ffargs+=("$OUTPUT")

    local AUDIO_DISPLAY="-c:a copy"
    (( AUDIO_IDX == 1 )) && AUDIO_DISPLAY="-an"
    local RATE_DISPLAY="(none)"
    [[ "$TARGET_MB" != "0" ]] && RATE_DISPLAY="-maxrate ${MAXRATE}k -bufsize ${BUFSIZE}k"

    echo ""
    echo " ================================================"
    echo " Res:    ${CHOSEN_RES}"
    echo " FPS:    ${CHOSEN_FPS}"
    echo " Codec:  ${CHOSEN_CODEC}"
    echo " CRF:    ${CHOSEN_CRF}"
    echo " Dedup:  ${DEDUP_MODE}"
    echo " Audio:  ${AUDIO_DISPLAY}"
    echo " Rate:   ${RATE_DISPLAY}"
    echo " Output: ${filestem}${SUFFIX}.mp4"
    echo " ================================================"
    echo ""

    ffmpeg "${ffargs[@]}"

    echo ""
    echo " [done] ${filename}"
    echo ""
}

# ───── entry point ──────────────────────────────
if [[ $# -eq 0 ]]; then
    # No arguments: open a file picker
    local chosen
    chosen=$(osascript <<'EOF'
set fileList to choose file with prompt "Select video file(s) to transcode" with multiple selections allowed
set output to ""
repeat with f in fileList
    if output is not "" then set output to output & linefeed
    set output to output & POSIX path of f
end repeat
return output
EOF
    ) || { echo " No file selected."; exit 0; }
    while IFS= read -r line; do
        [[ -n "$line" ]] && main "$line"
    done <<< "$chosen"
else
    for f in "$@"; do
        main "$f"
    done
fi

echo " All done. Press Enter to close."
read -r