A simple Linux shell script for translating an .srt file into another language and merging both languages into an .ass file

transmerge.sh

#!/bin/sh

#
#  This program takes an .srt file, translates it, and merges both translations into a .ass file with the user's selected
#  language on top of the screen and the other language at the bottom.
#
#  Usage: ./transmerge.sh [source language] [target language] [language on top (en|fri|...)] [source .srt] [target .ass (optional)]
#
#      ex., $ ./transmerge.sh en fr en movie.srt
#
#      New file: movie.ass
#
#  Above translates English to merged English+French with English displaying at the top of the screen and French the bottom.
#

source_lang=$1
target_lang=$2
top=$3
source_file=$4
file_saved=$5
sleep_s=12
lines=0
count=0

[ "$top" == "$source_lang" ] && bot=$target_lang || bot=$source_lang 
[ "$file_saved" == "" ] && file_saved=$(echo $source_file | sed "s/\.srt$/\.ass/g")
file_saved=$file_saved"."$(date +"%m%d%H%M%S")
formatted_file=$file_saved".1"

filetype=$(file -i $source_file | awk -F'=' '{print $2'})
[ "$filetype" == "utf-8" ] && iconv -f $filetype $source_file -o $formatted_file || perl -CS -pwe '' $source_file > $formatted_file
perl -i -CS -ane 's/<i>//g; s/<\/i>//g; s/- //g; s/\*//g; s/\r//g; $n=(@F==0) ? $n+1 : 0; print if $n<=1' $formatted_file

substart="[Script Info]\n\
ScriptType: v4.00+\\n\
Collisions: Normal\\n\
PlayDepth: 0\nTimer: 100,0000\n\
Video Aspect Ratio: 0\n\
WrapStyle: 0\n\
ScaledBorderAndShadow: no\n\
\n\
[V4+ Styles]\n\
Format: Name,Fontname,Fontsize,PrimaryColour,SecondaryColour,OutlineColour,BackColour,Bold,Italic,Underline,StrikeOut,ScaleX,ScaleY,Spacing,Angle,BorderStyle,Outline,Shadow,Alignment,MarginL,MarginR,MarginV,Encoding\n\
Style: "$top",Arial,10,&H00F9FFFF,&H00FFFFFF,&H00000000,&H00000000,-1,0,0,0,100,100,0,0,1,1,0,8,10,10,10,0\n\
Style: "$bot",Arial,18,&H00F9FFF9,&H00FFFFFF,&H00000000,&H00000000,-1,0,0,0,100,100,0,0,1,2,0,2,10,10,10,0\n\
\n\
[Events]\n\
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text"
echo -e $substart > $file_saved

for task in "Formatting" "Translating"; do

   echo -e "\n\n"$task" "$(echo $source_file | rev | cut -f 2- -d '.' | rev)".srt ...\n\n\n"$substart

   while read -r lineNum; read -r lineTime; read -r lineText; do

      ## Only loop if no empty text is found
      while [[ $lineText =~ [^[:space:]] ]]; do ## [ "$lineText" != "" ]
         text=$text$lineText" "
         read -r lineText
      done

      if [ "$task" == "Translating" ]; then
         translation=$(wget -U "Mozilla/5.0" -q -O- "http://translate.googleapis.com/translate_a/single?client=gtx&sl=$source_lang&tl=$target_lang&dt=t&q=$text" | perl -lne 'push @a,/(?<!\,\[\[)\[\"(.*?)(?<!\\)\"/g;END{print "@a"}' | perl -CS -pwe 's/\N{U+005C}\N{U+0022}/\N{U+0022}/g;')
         #translation=$(trans -s $source_lang -t $target_lang -b "$text")
      else
         translation=$text
      fi

      ## Add\Remove a space for question marks, exclamation marks, colons... depending on language
      if [ "$source_lang" == "fr" ]; then
         text=$(echo $text | perl -CS -pwe 's/((?!=\w)\s(?=[!|?|;|:]))//g; s/((?<=[\w|\s])[!|?|;|:])/ $&/g; s/\N{U+00AB}(?=\S)/$& /g; s/(?=\S)\N{U+00BB}/ $&/g; ')
      else
         text=$(echo $text | sed 's/ !/!/g; s/ ?/?/g; s/ :/:/g; s/ ;/\;/g;')
      fi

      ## “ = U+201C, ” = U+201D, ' = U+0027 , " = U+0022, « = U+00AB, » = U+00BB
      if [ "$target_lang" == "fr" ]; then
         translation=$(echo $translation | perl -CS -pwe 's/((?!=\w)\s(?=[!|?|;|:]))//g; s/((?<=[\w|\s])[!|?|;|:])/ $&/g; s/\N{U+00AB}(?=\S)/$& /g; s/(?=\S)\N{U+00BB}/ $&/g;')
      else
         translation=$(echo $translation | sed 's/ !/!/g; s/ ?/?/g; s/ :/:/g; s/ ;/\;/g;')
      fi

      ## Grab and incorperate timeline info. This shell command is faster than awk, sed, and cut
      timeStamp="Dialogue: 0,"${lineTime:1:7}"."${lineTime:9:2}","${lineTime:18:7}"."${lineTime:26:2}","
      first=$timeStamp$top",,0000,0000,0000,,"$([ "$top" == "$source_lang" ] && echo $text || echo $translation)
      second=$timeStamp$bot",,0000,0000,0000,,"$([ "$top" != "$source_lang" ] && echo $text || echo $translation)

      if [ "$task" == "Translating" ]; then
         count=$((count + 1))  
         printf "%s\n%s\n" "$first" "$second" |tee -a $file_saved

         ## Don't sleep after last translation as it's not necessary
         if [[ $lines -ne $count ]]; then
             percentage=$(( ($count*100)/$lines ))
             echo -n $'\e[s' ## Save cursor position

             for (( i=$sleep_s; i>0; i-- )); do
                timeleft=$(date -d@$(( ($lines-$count-1)*$sleep_s+$i )) -u +%H:%M:%S)
                echo -e -n "\e[7m\e[1mFile: "$source_file"   Logical line: "$count" / "$lines" ("$percentage"%)   Real line: "$lineNum" / "$realLines"   Time left: "$timeleft"   Next translation: "$i"s... "$'\e[u'
                sleep 1
             done

             ## Print spaces to delete info line then reset cursor to previous position
             printf "%-135s %s" "Translating..." $'\e[u'
         fi
      else
         lines=$((lines + 1))
         printf "%s\n%s\n" "$first" "$second"
         realLines=$lineNum
      fi

      text=""
   done < $formatted_file
done

new_file_saved=$(echo $file_saved | rev | cut -f 2- -d '.' | rev)
mv $file_saved $new_file_saved
rm $formatted_file

echo -e "\n\nDone!\n\n"
echo "cat "$(pwd)"/"$new_file_saved
echo "vi "$(pwd)"/"$source_file

How does it work?

Take an .srt file, such as this one:

sample.srt:

1
00:01:29,000 --> 00:01:30,131
C'était vers 1912.

2
00:01:30,471 --> 00:01:32,121
Jules, étranger â Paris,
avait demandé â Jim

3
00:01:32,201 --> 00:01:34,111
qu'il connaissait â peine
de le faire entrer

4
00:01:34,191 --> 00:01:36,861
au bal des Quat'z -Arts.
Jim lui avait procuré une carte

5
00:01:36,941 --> 00:01:38,431
et l'avait amené chez le costumier.

~ Courtesy Jules et Jim (1962)

Make the script executable:
$ chmod +x transmerge.sh

Run the script with the filename:
$ ./transmerge.sh fr en en sample.srt

The above command tells transmerge that the source language is French, the target language is English and that English will be displayed on top, French, on the bottom.

The resulting file is:

sample.ass:

[Script Info]
ScriptType: v4.00+
Collisions: Normal
PlayDepth: 0
Timer: 100,0000
Video Aspect Ratio: 0
WrapStyle: 0
ScaledBorderAndShadow: no

[V4+ Styles]
Format: Name,Fontname,Fontsize,PrimaryColour,SecondaryColour,OutlineColour,BackColour,Bold,Italic,Underline,StrikeOut,ScaleX,ScaleY,Spacing,Angle,BorderStyle,Outline,Shadow,Alignment,MarginL,MarginR,MarginV,Encoding
Style: en,Arial,10,&H00F9FFFF,&H00FFFFFF,&H00000000,&H00000000,-1,0,0,0,100,100,0,0,1,1,0,8,10,10,10,0
Style: fr,Arial,18,&H00F9FFF9,&H00FFFFFF,&H00000000,&H00000000,-1,0,0,0,100,100,0,0,1,2,0,2,10,10,10,0

[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:01:29.00,0:01:30.13,en,,0000,0000,0000,,It was around 1912.
Dialogue: 0,0:01:29.00,0:01:30.13,fr,,0000,0000,0000,,C'était vers 1912.
Dialogue: 0,0:01:30.47,0:01:32.12,en,,0000,0000,0000,,Jules, a stranger in Paris, had asked Jim
Dialogue: 0,0:01:30.47,0:01:32.12,fr,,0000,0000,0000,,Jules, étranger â Paris, avait demandé â Jim
Dialogue: 0,0:01:32.20,0:01:34.11,en,,0000,0000,0000,,he barely knew to bring him in
Dialogue: 0,0:01:32.20,0:01:34.11,fr,,0000,0000,0000,,qu'il connaissait â peine de le faire entrer
Dialogue: 0,0:01:34.19,0:01:36.86,en,,0000,0000,0000,,at the Quat'z -Arts ball. Jim had given him a card
Dialogue: 0,0:01:34.19,0:01:36.86,fr,,0000,0000,0000,,au bal des Quat'z -Arts. Jim lui avait procuré une carte
Dialogue: 0,0:01:36.94,0:01:38.43,en,,0000,0000,0000,,and brought him to the costumer.
Dialogue: 0,0:01:36.94,0:01:38.43,fr,,0000,0000,0000,,et l'avait amené chez le costumier.

Here is an example of how a generated .ass subtitle file might look in a video player. VLC player is used in this case. Please note that not all players accent .ass format:

Screenshot from 2020-03-25 11-25-46

good thanks