2
具有以下,和MP3文件:AVAssetTrack:音軌沒有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
需要注意的是賽道本身是好的,當我使用它以後。我想這可能是一個異步鍵 - 值編碼的問題,但這個NSParameterAssert
似傳:
AVKeyValueStatus trStatus = [audioTrack statusOfValueForKey:@"timeRange"
error:&theError];
NSParameterAssert(trStatus == AVKeyValueStatusLoaded);
這是怎麼回事?這只是格式的一個怪癖?