Question

In my iOS app (SDK 5.6), I create an AVURLAsset from a short video, like so:

AVURLAsset *asset = [AVURLAsset URLAssetWithURL:assetURL options:nil];

This seems to work fine. If I examine the asset in gdb, it looks like this:

(gdb) po asset
<AVURLAsset: 0x1a1c40, URL = file://localhost/var/mobile/Applications/A2142D8E-BC19-4E0B-A4C8-ABED4F7D4970/Documents/sample_iTunes.mov>

I use a sample .mov file from the Apple website, stored in the app’s Documents directory.

I would like to know the duration of this video, for further processing, but when I examine the duration property, I get this:

(gdb) po asset.duration
There is no member named duration.

What am I doing wrong? Is there any other way to determine the duration of an AVAsset or AVAssetTrack?

TIA: John

Answer 1

Creating the asset, however, does not necessarily mean that it’s ready for use. To be used, an asset must have loaded its tracks. Load the asset with

[asset loadValuesAsynchronouslyForKeys:[NSArray
arrayWithObject:tracksKey] completionHandler:
^{
// The completion block goes here.
}];

And there should be a ‘duration’ key in the array.

When loading completes, get the duration with

Float64 durationSeconds = CMTimeGetSeconds([<#An asset#> duration]);