2
具有以下,和MP3文件:AVAssetTrack:音轨没有timeRange?
AVURLAsset* audio = [[AVURLAsset alloc]initWithURL:audioUrl options:nil];
AVAssetTrack* audioTrack = [[audio tracksWithMediaType:AVMediaTypeAudio]
objectAtIndex:0];
CMTime audioDuration = audio.duration;
NSLog(@"audioDuration: %qi/%i; audioTrackDuration: %qi/%i",
audioDuration.value, audioDuration.timescale,
audioTrack.timeRange.duration.value,
audioTrack.timeRange.duration.timescale);
我得到:
audioDuration: 1513728/44100; audioTrackDuration: 0/1
需要注意的是赛道本身是好的,当我使用它以后。我想这可能是一个异步键 - 值编码的问题,但这个NSParameterAssert
似传:
AVKeyValueStatus trStatus = [audioTrack statusOfValueForKey:@"timeRange"
error:&theError];
NSParameterAssert(trStatus == AVKeyValueStatusLoaded);
这是怎么回事?这只是格式的一个怪癖?