Text search in audio-video file using subtitle file

Sometimes it happens that when watching movie/video or listening to a long speech/song we are only interested in the part where speaker is talking of some specific context but we have no option to search for that part other than going through the complete audio/video file. For example: A user may be interested only in listening to that part of the Obama's talk where he talks about Foreign policies rather than going through the complete video. If given an option then the user can search for "Foreign policies" as a text in the video and then can jump/seek directly to that particular instance to watch the part.

How to tackle this problem: To search for some specific word/line in an audio/video file either there is need to implement the speech to text algorithm and then search for the text or some complex speech recognition algorithm both which is not reliable to give 100% accurate results. Rather than following these approaches user can search in the subtitles (.srt or may be some other subtitle format) file associated with that audio/video for that word/line and can jump directly to that instance to see that part of the clip. The format of the subtitle file (.srt) is such that it has time stamp in the beginning of each line followed by the line which the speaker is speaking. So if a text is search in that file (like a normal text search in the .txt file) it can give the time stamp corresponding to that particular text field and then the audio-video player can be browsed or can be jumped (seek) to that particular location of interest. If more than one field is return in the search then the player can return all the time stamps of that search and user can select which position he/she wants the video to jump/seek. This feature can be integrated in the existing audio-video players with an ease because already the players know how to read the subtitle (.srt) files and show it on the video.

 Various advantages from this:

1. It can be integrated in the existing audio-video players with an ease because already the players know how to read the subtitle (.srt) files and show it on the video. 
2. It can also support multi language search like Chinese, Hindi, Japanese, etc because a simple text search supports multi language search and the subtitles can be made available in many languages. 
3. To support this feature if subtitle file is being added (coupled) to the existing or new audio/video files then the increase in the file size is not very significant since the file size of the .srt files is in kbs only. 
4. For almost all the big movies and songs, subtitles file is already available. Hence it would be easy to support search in the already existing files. 
5. This idea is not specific to mobile phones only. It can be used for any audio-video player whether it is desktop application or mobile one or it can be separate unit of audio-video player or iPods, etc. 
6. Since it is a simple text search in a files, it will be pretty fast also and easy to implement. 
7. Also this technology can be used in video searches over the internet since most of the searches on internet are made through text fields only. So, to search a video over the internet which all contains some text of interest, user can search for such words/phrases in subtitles file and get the relevant video.

 etc...