Synchronize subtitle file based on audio fragments

I am working on a project that includes the automated download, synchronization and cleaning of subtitles for any given movie (video) file. I already built the automated download of the subtitles and cleaning of the (removing credits etc), but I am a bit stuck on the synchronization part. In my current approach I have the following: 1) I download subtitles based on filename of the video file 2) I extract audio fragments from the video file 3) *This is what is missing* I want to calculate the offset between the spoken words in the audio fragments and the subtitle file 4) I clean the subtitles For this project I only want to have the functionality of number 3 provided. So the functionality should take 5 audio fragments of 20seconds and the start position of these audio files (so that you exactly know when the the audio fragments in the movie start) and should calculate the difference between the subtitles and the time these sentences are spoken in the movie. My audio fragments I test with can be found here: [login to view URL]!dpxWDAzL!4vRoa53qxh-6_oFShmXj0l_QqA6why7ndcAZZb7g1ZE [login to view URL]!thBiQB4Q!duh7myW-_yyS4Ht3Q0DXfgsSICvXpidac12o_p-ejI0 [login to view URL]!80QQHTQL!jxJRRA82FUOmUsR0HmuG2umKRAsIQ-o0m1iB_bdLWYA I know this is something quite hard to accomplish, hence the high value of this project. If you can convince me with the successrate of the functionality, it's more than worth it to me.