Is it possible to play a video on iPhone and have a subtitles synchronized with it show up?

Question

I want to add a "subtitles" to a video played in an iPhone app. I don't want those subtitles encoded into the video itself - ideally I'd love to have a view showing the video (with pause, play, volume and such standard controls) together with a view displaying the text that changes together with movie time changing.

If I drawn that, it's something like this,

So, basicly, I would need a way to get a method called when movie is playing, and then synchronize the text displayed on the label with the movie timing.

Anyone used a solution that was able to do it?

Answer 1

I've recently done something that syncs graphics to times in an audio track. The way I did it was by using the currentPlaybackTime property of the MPMediaPlayback interface (which the MoviePlayer controller should also conform to). This returns the seconds elapsed in the media, in a double (typedef'ed as NSTimeInterval). The actual synchronisation in my app was not done in notifications, as I couldn't find any resembling a "tick", but instead I created a timer, calling a function queried the currentPlaybackTime, and updated the graphics based on this.

In terms of your implementation, I would assume you have some kind of system for associating label text (subtitles) with a particular time. You could then compare the text's time range with the time returned from currentPlaybackTime to find the correct text to display.