I had the How to make a digital backup of your DVD collection wihtout qualtiy loss? The idea is to avoid losing your movie collection after years of use, and improve the cinematic experience by upgrading your subtitles from a sad images sequence to a real text file, which font and size you’ll be able to configure.
The process is quite easy with the right tools, this post will tell you how to do it on Windows.
Copying the disc
All commercial DVD are protected by encryption, which you’ ll need to get around (for personal backup reasons of course). The free open source software MakeMKV make it on the fly while reading the disc. Insert your disc, wait for MakeMKV to detect it and click on the big central icon. The software will automatically pass on the encryption and display the list of titles and chapters. This may take a few minutes, a few more if the disc is in a bad shape.
Select the movie track (usually the longer title, containing the more chapters), the audio track and your favorite subtitles. Choose an output folder and press “Make MKV”. Make sure your computer has enough disk space though : you will need around 4 GB per disc. Remember that MakeMKV does not compress the movie, it just clones it to your computer.
Well done, you now have a backup disc which you can play at anytime with VLC or any other media player.
DVD subtitles is the worst part of the archiving process: they’re not text file display on the movie track, they’re a blurry sequence of images with pixelated outlines which display badly on modern screens.
You can improve this by passing an OCR on every image and creating a real subtitle text file (you’ll even be able to correct a few misspelling on the process…)
First step: extract the subtitles track. We’ll use the free MKVExtractGUI software to extract the subs from your previously created MKV package. Open the soft, select your MKV as input file, select the track tagged as VOBSUB and extract. You’ll obtain two new files : .idx and .sub.
Second step: OCR the image files. The last free open source software you’ll need is Subtitle Edit. Go to “File” > “Import/OCR VobSub” and select your idx/sub files. Before starting the OCR, carefully selection the language of the subtitles and the language of the dictionary. Check “Italic”, uncheck “Music Symbol” (if you don’t want every interrogation mark interpreted as a music note…).
Every image will be teated and transformed in text. The operation will pause every time a word is not recognized, allowing you to choose between a dictionary suggestion or a manual correction. At the end of the operation you’ll get the possibility to modify your text again, search and replace characters or word.
The software also allow to modify the time position of any subtitle, while playing the video at the same time.
When satisfied, just save your work. You have created an highly configurable SRT file. Next time you play your MKV movie, select this new subtitle track to get an improved user experience.