iOS audio help

[MxDx]

I am using on currentTimeChanged theInterval to sync graphic objects in my app with the playback location of an audio file.
The player object is used for audio playback on Mac OS.
I need to implement this same functionality for the iOS platform.

I'm looking at mergAVPlayerCreate & mergAVPlayerCreatePeriodicTimeObserver to handle this.
#1 Is this the best way to implement it?
I'm still new to LC - the docs on these functions leaves me scratching my head.
#2 Are there any example files I might find somewhere. ( I've yet to find anything)

This is what I have so far - but it doesn't work. ( the path checks out)

Code: Select all

-- Path to the audio file
   put specialFolderPath("engine") & "/Audio Files/myMP3File" into tFilePath   -- myMP3File is a placeholder.
   
   --   -- Create a new AVPlayer object
   put mergAVPlayerCreate("avPlayer", ) into tPlayerID
   
   -- Set the file path for the player
   set the fileName of player tPlayerID to tFilePath
   
   --   -- Start playing the audio file
   play player tPlayerID[/indent]

Thanks in advance

[MxDx]

Wow 300 views and not one tip.
I guess mergAV isn't used much in LC.

[Emily-Elizabeth]

Code: Select all

   put mergAVPlayerCreate("avPlayer", ) into tPlayerID

What is "avPlayer" ?

[MxDx]

Code: Select all

   put mergAVPlayerCreate("avPlayer", ) into tPlayerID

What is "avPlayer" ?

Good question.
The LC documentation advertises the first argument to be - a pointer to an asset in memory?
I really don't understand asset in memory.

So I thought mergAVPlayerCreate("avPlayer", ) would create a player named avPlayer.
But now that I look at it, that doesn't make sense.
Maybe the asset is an audio file in my projects assets folder?
then I would suspect I don't need
-- Set the file path for the player
set the fileName of player tPlayerID to tFilePath
Well I have something to test.
Thanks for your response.

[jacque]

Why not use a standard player control? It works on all platforms.

[MxDx]

According to the LC docs
OS - mac, windows, linux
Platforms - desktop, server

[MxDx]

Why not use a standard player control? It works on all platforms.

The Player object function > currentTimeChanged doesn't work on iOS.
On the desktop I use this function to sync a graphic on the screen with the audio track.
So on mobile I would have to keep checking the audio track position with a loop or something which is my last resort.
mergAV has a mergAVPlayerCreatePeriodicTimeObserver fuction that would handle this.
I'm banging away on this with the help of GPT-4 ..ha ha

[jacque]

The player control does work on all platforms, but you're right that currentTimeChanged is only listed for desktop and server. You wouldn't have to loop though, LC sends a message every time the frame changes so all you'd need to do is write a handler to catch that message. If the current time is a key point that you've designated, then your handler can take action.

It's moot though if you're building for iOS. One other thing: I used callbacks in a project, which is similar to currentTimeChanged, to key audio to successive field text updates. It worked well on my machine and my client's, but when the app was used on slower or older machines it failed miserably. We didn't realize it for some time, but once we tested it, the delay was bad enough that we removed the feature entirely.

I agree that the mergAV documentation is pretty obscure. I don't quite understand it either.

[MxDx]

LC sends a message every time the frame changes

How do I grab that message?

[jacque]

LC sends a message every time the frame changes

How do I grab that message?

It's in the dictionary:

Code: Select all

on currentTimeChanged theInterval -- display the time in a field
  put theInterval into field "Time Code"
end currentTimeChanged

The contents of the handler would be whatever you want to do about the player's current time (the interval.) I think you'll get this message many times per second, so you'd want to designate certain intervals where the handler would act.

But if you are building for iOS then a player control won't work. But the "mobileControlCreate" command does work to create players on mobile. That's a bit more scripting though, since you have to create, manage, and delete the player instance in script. See the "mobileControlCreate" command in the dictionary. You can also use mobileControlGet to get the currentTime of the mobile player, but in this case you're right that you'd need to loop every second or two to see where the player is at. There's no automatic messaging that I know of, like there is for the desktop control.

[MxDx]

LC sends a message every time the frame changes

How do I grab that message?

It's in the dictionary:

Code: Select all

on currentTimeChanged theInterval -- display the time in a field
  put theInterval into field "Time Code"
end currentTimeChanged

I guess I wasn't clear enough in my first post that I have already implemented the Mac OS version of my app using currentTimeChanged.
But thanks for your reply.

I ended up going a different route then using the mergAV functions. Not as slick as I would like but it works.