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POAVAsset has no tracks or duration when created from an ALAsset URL
 

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  1. POAVAsset has no tracks or duration when created from an ALAsset URL
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    <p>I'm pulling all of the video assets from ALAssetsLibrary (Basically everything that's being recorded from the native camera app). I am then running an enumeration on each video asset that does this to each video:</p> <pre><code> // The end of the enumeration is signaled by asset == nil. if (alAsset) { //Get the URL location of the video ALAssetRepresentation *representation = [alAsset defaultRepresentation]; NSURL *url = [representation url]; //Create an AVAsset from the given URL NSDictionary *asset_options = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:YES] forKey:AVURLAssetPreferPreciseDurationAndTimingKey]; AVAsset *avAsset = [[AVURLAsset alloc] initWithURL:url options:asset_options];//[AVURLAsset URLAssetWithURL:url options:asset_options]; //Here is the problem NSLog([NSString stringWithFormat:@"%i", [avAsset.tracks count]]); NSLog([NSString stringWithFormat:@"%f", CMTimeGetSeconds(avAsset.duration)]); } </code></pre> <p>NSLog is reporting that the AVAsset that I've gotten from my ALAsset has 0 tracks, and has a duration of 0.0 seconds. I checked the url, and it's "assets-library://asset/asset.MOV?id=9F482CF8-B4F6-40C2-A687-0D05F5F25529&amp;ext=MOV" which seems correct. I know alAsset is actually a video, and the correct video, because I've displayed alAsset.thumbnail, and it's shown the correct thumbnail for the video.</p> <p>All this leads me to believe there's something going wrong in the initialization for avAsset, but for the life of me, I can't figure out what's going wrong. Can anyone help me?</p> <p><strong>Update:</strong></p> <p>I think i've confirmed that the url being given to me by ALAssetRepresentation is faulty, which is weird because it gives me the correct thumbnail. I added this code in:</p> <pre><code>NSLog([NSString stringWithFormat:@"%i", [url checkResourceIsReachableAndReturnError:&amp;error]]); NSLog([NSString stringWithFormat:@"%@", error]); </code></pre> <p>It gives me this:</p> <pre><code>0 Error Domain=NSCocoaErrorDomain Code=4 "The operation couldn’t be completed. (Cocoa error 4.)" UserInfo=0x19df60 {} </code></pre> <p>I'm still not sure what would cause that. The only thing I'm noticing is the url, which is "assets-library://asset/asset.MOV?id=9F482CF8-B4F6-40C2-A687-0D05F5F25529&amp;ext=MOV" is different from what I've seen as I've been searching around for this. The one i've seen elsewhere looks more like "assets-library://asset/asset.MOV?id=1000000394&amp;ext=MOV", with a number instead of an alphanumeric, dash separated name. </p> <p>If it helps, I'm using XCode 4.2 Beta, and iOS5. Please let me know if you can think of anything. Thanks.</p>
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