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Author Topic: How to Convert .SUB and .IDX Subtitles to .SRT Subtitle file/s.  (Read 29473 times)


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How to Convert .SUB and .IDX Subtitles to a .SRT Subtitle files.

This is the text only version of the tutorial, so any reference to pictures etc will have to be guessed at.
Although, if you print this out first, then it may help when actually editing the .SUB file.
Also some of the text refers to .AVI movies which have been split into two parts, but again this will make sense as you go.

Sometimes you encounter .SUB and .IDX (Vobsub subtitles) and the program you are using to convert the AVI to DVD like ConvertXtoDVD for example, takes anything but those type of files.
The usual format for Subtitles are .SRT so let's convert to that.
(Since this was first written later versions of ConvertXtoDVD now recognise .SUB and .IDX files) "But you can't edit those as you can with .SRT files""

Just a reminder before we get started.
If you find there are any errors after viewing with VLC Player, then the .SRT file can be edited using "Notepad" (but do not alter the times)
Oh, and don't let this somewhat lengthy document put you off, it's actually a lot easier than it may sound.

* * * * * ** *
OK, here we go:

First you will need to have access a program called "SubResync" which is part of "Vobsub" and also "VLC Player"
You need VLC Player to find out what the FPS (Frames Per Seconds) of the avi file/s are and also to test the outcome before burning.

Once you have both installed, use VLC to open the first AVI.
Once you have it open, go to View > Stream and Media Info.
Now click the Advanced Information tab.
Then under Stream 0 (Which is the video stream) it displays the Frame Rate.
This is usually one of the following values:-


If it isn't one of those, then I guess you're screwed and that release sucks.
Once you see the Frame Rate, that's the same thing as Frames Per Second (FPS), which you will need later on, so write it down (This piece of information is crucial).

Now run SubResync which got installed when you installed VobSub (Should be in the VobSub folder in the Start Menu).
Click on the Open button and set the correct FPS in the drop down list to the bottom left of the Cancel button.
Then proceed to open the FIRST .SUB file.

Now you will see a drop down list under the Reset timing button.
From this list you will want to choose the language, usually it's 00 - English, which is what it's set to by default.
Render should be set, and Unlink shouldn't be set.

Now click Save As. and in the new window that pops up, make sure you set Save as type: to Subripper (*.srt).
Then click Save.

Now comes the fun part,  :-X
The main window will expand and at the bottom and will show words or phrases, and a small window will pop up.
In this small window it will show a text box and an image of a letter at the right.
What you are going to do is type the letter it shows you. So in this case at the bottom, I would press 'M' and press ENTER. (IF M was the correct letter)
The reason you are doing this is because SUB and IDX subtitles are what they call “Image Subtitles”, and you want to convert them to SRT which are text subtitles.
What this program is doing is using Optical Character Recognition (OCR) to map each letter image to a text letter.
So basically you're going to do this until it has all the letters used in the subtitle and all variations of it.
The red box at the bottom shows what letter or character sequence you are currently typing.

Sometimes you will encounter punctuation. Usually you just type it in, for example the red box will be around a period character and so you just type the period.
However, sometimes it's a letter you already typed but it's followed by punctuation.
For example say you've already typed in 'e', but now it's asking you for 'e' again except it's immediately followed by an exclamation mark.
This is because there is a variation in the image which made it not be able to detect the 'e' like it did last time.
What you would do in this case is click the “Extend” button so that the red box at the bottom includes the exclamation mark.
Now what you would do is type 'e!' into the box. If it ever encounters that same character sequence, 'e!', it won't ask you again.

This might seem tedious but you get used to it.
You can get into the mood and begin to do it pretty quickly, but still be careful because any mistakes will be transferred into the end result.

Sometimes you will get two or more letters in the box. This is because the images of the letters are merged and the OCR system in SubResync can't tell them apart.
This is fine though because you can. Simply type both letters (Or more depending on your situation) and you'll be fine.

Sometimes the red box will select one letter and half of another. This is for the same reason as above except it's a weird situation where it confuses the OCR into thinking that the first half of the second letter is part of the first letter, disconnected from the second.
What you would do in this case is click the “Extend” button so that the red box at the bottom includes the second letter.

Sometimes you'll get the red box over the top dot of a colon  ':'. You can't just type a period and be done with it, you have to click Extend so that it highlights both dots (Possibly even the next character).

You will want to use the Extend button again, otherwise if you only type 'f' in the above example, in the end result it will spell fiendly, and it will replace any other

occurrence of the italicised 'fr' with 'f'. So click Extend so that it includes both characters and type both letters.
If after extending, it happens again, keep doing it until only complete letters are included, even if it means having to extend until the end of the entire word.

You know you're done when suddenly there's no more letters to type and you're back at the usual main window.

If you have a split .AVI file (Part 1 & Part 2) then repeat the ENTIRE process again with the second AVI.
Don't freak out! SubResync can save the information you typed in before, so this time it will only ask you for any new character/character sequences it encounters.
NOTE: (If you don't want this to happen and you want to clear the database before you convert the subtitle file, if for example you had mistakes in the previous one or you simply want to start over for fun or because you think the styling is different in these subtitles, you set the Clear image->letter(s) database option when you hit Save As...)

Chances are that the second avi is the same framerate as the first one so you shouldn't have to check, but the check only takes a few seconds so it wouldn't hurt to double check.

If you have two SRT files you can now try them/it out with VLC.
Simply put each SRT in the same folder as the AVI file it was created from.
For example, put the "Movie Part 1.SRT" file in the same folder as the "Movie Part 1.AVI"
Make sure both the avi and the srt files have exactly the same name (Excluding of course, the extension) and play the avi in VLC, it should automatically import the SRT file.

To join two SRT files together, use "SRT File Joiner"

Out of curiosity I timed myself with converting a SUB/IDX  file to .SRT and with working at a reasonably careful pace it took me 20 minutes to convert a file, the result was also perfect without any mistakes.
« Last Edit: August 20, 2009, 12:41:12 PM by oldfogy »