AVMutableCompositionTrack - insertTimeRange - insertEmptyTimeRange issue
audio, avfoundation, iphone
Solution
Still don't know what this "insertEmptyTimeRange" means. I made a work around with a "silence"-audio file which has nothing in it. I put this empty audio file between the two sound files and this does it for me. Question closed ;) (But if someone could explain this "insertEmptyTimeRange" this would be still interesting...)
Problem
I have a strange problem: I want to generate a new sound file out of two soundfiles and silence. sound1: 2 seconds long + silence: 2 seconds silence + sound2: 2 seconds long When I try the code below, I get a 6 seconds long soundfile with all the parts, but in a different order! The order is: sound1, sound2, silence I am not able to put this silence in the middle of this composition (also not at the beginning). Is this a typical behavior or do I something wrong? Here is the code for putting the segments together: ``` [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, [audio1 duration]) ofTrack:clipAudioTrack1 atTime:kCMTimeZero error:nil]; [compositionAudioTrack insertEmptyTimeRange:CMTimeRangeMake(kCMTimeZero, CMTimeMake(2, 1))]; [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, [audio2 duration]) ofTrack:clipAudioTrack2 atTime:CMTimeMake(4, 1) error:nil]; ``` Perhaps someone has an idea? Thank you in advance! By the way: following code without the insertEmptyTimeRange-line doesn't work either, it just generates 4 seconds of sound and sound2 slides to the end of sound1: ``` [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, [audio1 duration]) ofTrack:clipAudioTrack1 atTime:kCMTimeZero error:nil]; [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, [audio2 duration]) ofTrack:clipAudioTrack2 atTime:CMTimeMake(4, 1) error:nil]; ``` It seems that it is not allowed that there is "nothing" between segments!?