Ubuntu – MTS video files – how to merge and convert multiple files

You can resize and convert with ffmpeg using ffmpeg -i input.ogv -s widthxheight -sameq output.flv.
You can also change the video bit rate with -b:v bitarate and control the frame rate with -r framerate to reduce the size of outcome. As izx has mentioned the bit rate option is recommended over changing frame rate or dropping frames.

I've decided to gain some experience with Bash and wrote the below script, that has next features:

• It can handle all files and folders, placed into the current directory.
• If there are more than one subtitle or video file (except sample files), the script will ask for manual interaction.
• In all other cases the script will automatically move all files and folders into a backup directory (be careful where you run it!) , that will be moved into the user's trash folder, instead of to be deleted.
• It can handle several types of video and subtitle extensions.
• It uses mkvmerge to merge video with subtitle files also uses notify-send to show some messages in GUI. Also it uses gvfs-trash to move files in user's trash folder.
• It can be used as Nautilus script or as regular shell script but GIU environment is required while notify-send command exists into the script's body.
• The name of the output file could be based on the directory name (default) or on the name of the source video file.
• Additionally when only two files are selected (one video and one subtitle file), they will be merged and rest of the folder's content will be retained. The output file will be named after the source video file. This option is available only when the script is used as Nautilus script.

The script:

#!/bin/bash -e

# Check if all tools are available
[ -x /usr/bin/notify-send ] || (echo "Please, install 'notify-send'"; exit 1)
[ -x /usr/bin/mkvmerge ] || (echo "Please, install 'mkvmerge'"; exit 1)

# Allowed video and subtitle file extensions
EXT_VIDEO=("mp4 avi mpg mov mkv wmv")
EXT_SUB=("sub str srt vtt")

# Files, which names contains some of next strings will be removed in auto mode
FILTER=("sample Sample SAMPLE")

# Log file
MERGE_LOG="/tmp/merge-video-sub.log" 
echo > "$MERGE_LOG"

#
# Functions
#

function get-video-and-sub-file-names {
    # Get the names of the video and subtitle files and move the rest of the files into the Backup directory
    for ((i=0; i<${#FILE_LIST[@]}; i++)); do
        FILE_NAME="${FILE_LIST[$i]%.*}"
        FILE_EXT="${FILE_LIST[$i]##*.}"

        if   [[ "${EXT_SUB[@]}" == *"$FILE_EXT"* ]]; then
            SUB_FULL_FILE_NAME="${FILE_LIST[$i]}"
            SUB_FILE_NAME="${FILE_NAME}"
            SUB_FILE_EXT="${FILE_EXT}"
        elif [[ "${EXT_VIDEO[@]}" == *"$FILE_EXT"* ]]; then
            VIDEO_FULL_FILE_NAME="${FILE_LIST[$i]}"
            VIDEO_FILE_NAME="${FILE_NAME}"
            VIDEO_FILE_EXT="${FILE_EXT}"
        else
            # We need 'find' to manipulate only with files, because "$BACKUP_DIR" is in the queue
            find ./* -maxdepth 0 -type f -name "${FILE_LIST[$i]}" -exec mv "{}" "$BACKUP_DIR" \; -exec echo -e "The file {} was REMOVED.\n" >> "$MERGE_LOG" \;
        fi
    done
}

function get-the-content-of-the-current-directory {
    # Get the content of the current directory
    shopt -s nullglob
    FILE_LIST=(*)
    shopt -u nullglob
}

function mkvmerge-video-and-sub-files {
    # Create merged file
    mkvmerge -o "$OUTPUT_FILE" "$VIDEO_FULL_FILE_NAME" "$SUB_FULL_FILE_NAME"
    sleep 3
}

#
# Scenario 1: If exactly two files are selected in Nautilus! Then check if they are 1 video and 1 subtitle files, if yes - merge and remove them
# Scenario 2: Else run the standard procedure
#

# Get the files, selected in Nautilus as file list. Use next command to check the result: notify-send "MESSAGE" "`echo -e "${#FILE_LIST[@]}"; printf '%s\n' "${FILE_LIST[@]}"`"
IFS_BAK=$IFS
IFS=$'\t\n'
FILE_LIST=($NAUTILUS_SCRIPT_SELECTED_FILE_PATHS)
IFS=$IFS_BAK


if [ "${#FILE_LIST[@]}" -eq "2" ]
then # Scenario 1

    # Get the names of the video and subtitle files
    get-video-and-sub-file-names

    if   [[ "${EXT_SUB[@]}" == *" $SUB_FILE_EXT "* ]] && [[ "${EXT_VIDEO[@]}" == *" $VIDEO_FILE_EXT "* ]]
    then
        notify-send "OK" "`echo -e "The following files will be MERGED and MOVED to trash:"; printf '\t-\ %s\n' "${FILE_LIST[@]##*/}"`"

        # Construct the name of the merged file. 
        OUTPUT_FILE="${VIDEO_FILE_NAME}.sub.mkv"

        # Merge the files
        mkvmerge-video-and-sub-files        

        # Move video and subtitle files into user's trash directory and create trash infofile
        if [ -f "$OUTPUT_FILE" ]
        then
            gvfs-trash "$VIDEO_FULL_FILE_NAME"
            gvfs-trash "$SUB_FULL_FILE_NAME"            
            notify-send "OK" "`echo -e "THE NAME OF THE NEW MERGED FILE IS:\n${OUTPUT_FILE##*/}"`"
        else
            notify-send "ERROR 1" "`echo "Something went wrong!"`"
        fi
    else
        notify-send "ERROR" "`echo -e "\n\t\nTo use this function, please select exactly:\n\t- 1 video file and\n\t- 1 subtitle file!\n\t\nYou are selected these files:"; printf '\t-\ %s\n' "${FILE_LIST[@]##*/}"`"
    fi

else # Scenario 2

    # Get the current directory name
    DIR_NAME="${PWD##*/}"

    # Create Backup sub-directory 
    BACKUP_DIR="${DIR_NAME}.backup"
    [ -d "${BACKUP_DIR}" ] || mkdir "$BACKUP_DIR" && echo "The directory $BACKUP_DIR was CREATED.\n" > "$MERGE_LOG"

    # Move all sub-directories into the Backup directory
    shopt -s dotglob
    find ./* -maxdepth 0 -type d ! -name "*$BACKUP_DIR*" -prune -exec mv "{}" "$BACKUP_DIR" \; -exec echo "The directory {} was REMOVED.\n" >> "$MERGE_LOG" \;
    shopt -u dotglob

    # Move all files and folders, whose names contains a string, that exists in $FILTER[@]
    for f in $FILTER; do
        shopt -s dotglob
        find ./* -maxdepth 0 ! -name "*$BACKUP_DIR*" -type f -name "*$f*" -exec mv "{}" "$BACKUP_DIR" \; -exec echo "The file {} was REMOVED.\n" >> "$MERGE_LOG" \;
        shopt -u dotglob
    done

    # Get the entire content of the current directory
    get-the-content-of-the-current-directory

    # Get the names of the video and subtitle files and move the rest of the files into the Backup directory
    get-video-and-sub-file-names

    # Construct the name of the merged file. It could be based on the parent directory or on the video file name Make your choice and comment/uncomment next lines
    #OUTPUT_FILE="${VIDEO_FILE_NAME}.sub.mkv"
    OUTPUT_FILE="${DIR_NAME}.sub.mkv"

    # Get the entire content of the current directory after the filtering
    get-the-content-of-the-current-directory

    echo -e "$(cat $MERGE_LOG)" && notify-send "OK" "`echo -e "$(cat $MERGE_LOG)"`" && echo > "$MERGE_LOG"

    # Check the current structure of the directory
    if [ "${#FILE_LIST[@]}" -ne "3" ]; then
        echo "The content structure must consists of next 3 items:" > "$MERGE_LOG"
        echo "\t- 1 movie file,\n\t- 1 subtitle file and\n\t- 1 backup directory." >> "$MERGE_LOG"
        echo "\n\t\nThe current number of contained items is ${#FILE_LIST[@]}." >> "$MERGE_LOG" && echo >> "$MERGE_LOG"
        echo "\n\t\nPLEASE RESOLVE THIS MANUALLY!" >> "$MERGE_LOG"
        echo -e "$(cat $MERGE_LOG)" && notify-send "ERROR" "`echo -e "$(cat $MERGE_LOG)"`"
    else
        echo "The directory structure looks good, is contains ${#FILE_LIST[@]} items." > "$MERGE_LOG"
        echo " - The source VIDEO file is: ${VIDEO_FULL_FILE_NAME::21}... .${VIDEO_FULL_FILE_NAME##*.}" >> "$MERGE_LOG"
        echo " - The source SUB file is: ${SUB_FULL_FILE_NAME::25}... .${SUB_FULL_FILE_NAME##*.}" >> "$MERGE_LOG"
        echo "They has been merged and removed!" | tr /a-z/ /A-Z/ >> "$MERGE_LOG"

        # Merge the files
        mkvmerge-video-and-sub-files

        # Move video and subtitle files into the Backup directory
        mv "$VIDEO_FULL_FILE_NAME" "$BACKUP_DIR" 
        mv "$SUB_FULL_FILE_NAME" "$BACKUP_DIR" 

        # Move the Backup directory to trash and create trash infofile
        if [ -f "$OUTPUT_FILE" ]; then
            gvfs-trash "$BACKUP_DIR" 

            echo "\n\t\nThe Backup directory has been MOVED to Trash!\n\t\n" >> "$MERGE_LOG"
            echo "The name of the new merged file is:"  | tr /a-z/ /A-Z/ >> "$MERGE_LOG"
            echo "${OUTPUT_FILE##*/}" >> "$MERGE_LOG"
            echo -e "$(cat $MERGE_LOG)" && notify-send "OK" "`echo -e "$(cat $MERGE_LOG)"`"
        else
            echo "Something went wrong!" && notify-send "ERROR 2" "`echo "Something went wrong!"`"
        fi

    fi
fi

rm "$MERGE_LOG"
exit 1

Setup:

• Create executable file and paste the above content inside. Let's call this file merge-video-sub:

  touch merge-video-sub 
  chmod +x merge-video-sub
  nano merge-video-sub
  

• Copy (or ln -s) this file into the folder ~/.local/share/nautilus/scripts to make it available as Nautilus script for the current user.

• At the moment I can't find a way how to make it available system wide as Nautilus script.

• Copy the file into ~/bin (and add export PATH=$PATH:~/bin to the bottom of ~/.bashrc if is needed) to make it available as shell command for the current user.

• Copy the file into /usr/local/bin to make it available as shell command system wide.

• The short way is to curl the script from my PasteBin directly into nautilus/scripts folder:

  curl https://pastebin.com/raw/HrLTibuR | sed -e 's/\r$//' > $HOME/.local/share/nautilus/scripts/merge-video-sub
  chmod +x $HOME/.local/share/nautilus/scripts/merge-video-sub
  

Demo:

• The previous demo

Additional references:

• Encode forced subtitles using mkvmerge
• How to merge srt, idx or sub subtitles with MKV in seconds
• ToolSlick: SUB to SRT Converter and SubtitleTools: Convert Sub/Idx to Srt