SNES Development
Working with Audio and Video

Managing Media Files

Setup

brew install ffmpeg mediainfo mkvtoolnix mp4box

Handbrake Subler

mv SublerCLI /usr/local/bin/SublerCLI

Identifying Problems in Files

mediainfo source.mkv

Convert Audio

Extract AC3 / DTS

ffmpeg -i video.mkv -acodec copy audio.ac3

Convert to AC3

ffmpeg -i audio.dts -acodec ac3 -ab 448k -ac 6 output.ac3

Convert to AAC

ffmpeg -i audio.dts -acodec aac -ab 192k -ac 2 -strict -2 output.m4a
ffmpeg -i audio.dts -acodec libfaac -ab 192k -ac 2 output.m4a

Convert to AAC 5.1

ffmpeg -i audio.dts -acodec aac -ab 1536k -ac 6 -strict -2 output.m4a
ffmpeg -i audio.dts -acodec libfaac -ab 1536k -ac 6 output.m4a

Convert to FLAC

ffmpeg -i audio.dts output.flac

Convert Container

Convert AVI to MKV

Ordering of tracks will change with from file to file.

for video in *.avi; do
    filename=$(basename "$video" .avi)
    echo "Processing $filename ...";
    /Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -o "${filename}.mkv" \
        --language "0:eng" --track-name "0:XVID" --forced-track "0:no" \
        --language "1:eng" --track-name "1:MP3 2.0" --forced-track "1:no" \
        --audio-tracks 1 --video-tracks 0 \
        --no-subtitles --no-track-tags --no-global-tags --no-chapters \
        "${filename}.avi" --track-order "0:0,0:1"
done

Convert MKV to MP4

Alternatives: https://github.com/Bilalh/MKV-Utilities/blob/master/encoding.sh https://github.com/flexiondotorg/MKV-to-MP4/blob/master/MKV-to-MP4.sh

SublerCLI -source source.mkv -dest source.mp4

for video in *.mkv; do
    filename=$(basename "$video" .mkv)
    echo "Processing $filename ...";
    SublerCLI -source "${filename}.mkv" -dest "${filename}.mp4"
    mp4box -unhint "${filename}.mp4"
    mp4box -hint "${filename}.mp4"
done

ffmpeg -i input.mkv -vcodec copy -acodec copy -scodec copy
ffmpeg -i input.mkv -vcodec copy -acodec aac -ab 192k -ac 2 -strict -2 output.m4a -scodec copy # (2ch)
ffmpeg -i input.mkv -vcodec copy -acodec aac -ab 1536k -ac 6 -strict -2 output.m4a -scodec copy # (5.1ch)

Convert MP4 to MKV

/Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -o "destination.mkv" \
    --language "0:eng" --track-name "0:6ch AC3" --default-track "0:yes" --forced-track "0:no" --compression "0:none" \
    --language "1:eng" --track-name "1:x264"    --default-track "1:yes" --forced-track "1:no" --compression "1:none" --display-dimensions "1:1280x720" \
    --audio-tracks 0 --video-tracks 1 --no-subtitles --no-track-tags --no-global-tags --no-chapters \
    "source.mkv" --track-order "0:1,0:0"

Convert FLV to MP3

The same applies to any supported audio codec in the FLV.

ffmpeg -i source.flv -vn -acodec copy destination.mp3

Convert FLV to MKV/MP4

This assumes that the MKV/MP4 container accepts the audio / video format in the FLV.
Windows

ffmpeg -i source.flv -vcodec copy -acodec copy destination.mkv
ffmpeg -i source.flv -vcodec copy -acodec copy destination.mp4

Fixing MP4 Hinting Metadata

mp4box -unhint source.mp4
mp4box -hint source.mp4

for video in *.mp4; do
    filename=$(basename "$video" .mp4)
    echo "Processing $filename ...";
    mp4box -unhint "${filename}.mp4"
    mp4box -hint "${filename}.mp4"
done

Fixing MKV Metadata

Remove Header Compression

Some hardware players have issues with header compression introduced in 4.0.0

/Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -o "destination.mkv" \
    --no-attachments --compression '-1:none' \
    "source.mkv"

Reorder and Correct Tracks

/Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -o "destination.mkv" \
    --language "0:eng" --track-name "0:6ch AC3" --default-track "0:yes" --forced-track "0:no" --compression "0:none" \
    --language "1:eng" --track-name "1:x264"    --default-track "1:yes" --forced-track "1:no" --compression "1:none" --display-dimensions "1:1280x720" \
    --audio-tracks 0 --video-tracks 1 --no-subtitles --no-track-tags --no-global-tags --no-chapters \
    "source.mkv" \
    --track-order "0:1,0:0"

Reorder and Correct Tracks in Groups of Files

for video in *.mkv
do
    filename=$(basename "$video" .mkv)
    audio_track_id=$(/Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -i "$video" | grep -m 1 "audio" | cut -d ":" -f 1 | cut -d " " -f 3)
    video_track_id=$(/Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -i "$video" | grep -m 1 "video" | cut -d ":" -f 1 | cut -d " " -f 3)
    # echo " $filename : $audio_track_id : $video_track_id ";
     /Applications/Mkvtoolnix.app/Contents/MacOS/mkvmerge -o "${filename}.clean.mkv" \
        --language "${audio_track_id}:eng" --track-name "${audio_track_id}:2ch AC3" --default-track "${audio_track_id}:yes" --forced-track "${audio_track_id}:no" --compression "${audio_track_id}:none" \
        --language "${video_track_id}:eng" --track-name "${video_track_id}:x264"    --default-track "${video_track_id}:yes" --forced-track "${video_track_id}:no" --compression "${video_track_id}:none" --display-dimensions "${video_track_id}:1280x720" \
        --audio-tracks $audio_track_id --video-tracks $video_track_id --no-subtitles --no-track-tags --no-global-tags --no-chapters \
    "${filename}.mkv" \
        --language "0:eng" --track-name "0:SRT" --forced-track "0:no" --subtitle-tracks 0 --no-video --no-audio --no-track-tags --no-global-tags --no-chapters "${filename}.srt" \
        --track-order "0:${video_track_id},0:${audio_track_id},1:0"
done

Misc.

Extract Fonts from MKV

for i in $*; do
    echo $i
    ids=`mkvmerge -i "$i"  | grep -oP '(?<=Attachment ID )[0-9]+'`
    for id in $ids; do
        mkvextract attachments "$i" $id
    done
done

Extract Subtitles from MKV

for i in *.mkv; do
    echo "$i"
    #Subs=`MediaInfo "$i" | grep -A 1 Text | grep ID | head -n 1 | grep -oP "\d+"`
    Subs=`mkvmerge -i "$i" | grep 'subtitles' | grep -oP '(?<=Track ID )\d+'`
    Name=${i%.*}
    mkvextract tracks "$i" ${Subs}:${Name}.ssa
done

Extract Audio from MKV

for i in *.mkv; do
    filename=$(basename "$i" .mkv)
    ffmpeg -i "$i" -acodec copy "${filename}.ac3"
done