"_CMTimeGetSeconds", símbolo (s) no encontrado para la architecture armv7 -IOS

Al usar este código

AVPlayerItem *playerItem = [AVPlayerItem playerItemWithURL:selectedVideoUrl]; CMTime duration = playerItem.duration; float seconds = CMTimeGetSeconds(duration); NSLog(@"duration: %.2f", seconds); 


 Undefined symbols for architecture armv7: "_CMTimeGetSeconds", referenced from: -[VideoUpload imagePickerController:didFinishPickingMediaWithInfo:] in VideoUpload.o ld: symbol(s) not found for architecture armv7 clang: error: linker command failed with exit code 1 (use -v to see invocation) 

CMTime se define en CoreMedia.framework. Agregue ese marco a su proyecto.

Y eche un vistazo a la reference CMTime de Apple