将由多个wav文件组成的单个wav文件导出到iPhone音乐库

Question

Is there any API for iOS that allows me to create a WAV file made up of several other WAV samples? I am making a beat making app, the beat sound themselves are made of several small wav sounds like kick.wav, snare.wav etc. I want to assemble all these separate .wav sounds based on user's pattern to make a final output.wav. What should be the way to do this for iOS platform?

Answer 1

There is no iOS API to do anything like that directly, file to file.

The sequence of steps to do it manually might include reading the WAV files into buffers of raw PCM samples (AVAssetReader), resampling if the sample rates aren't all appropriate, compositing the samples at appropriate time offsets using a DSP mixer (including gain control and limiting), then writing the resulting composite vector as a new WAV file.

Each of those steps might be a separate questions, and for more than one stackexchange site, as there is more than one way to resample and mix down samples, and doing it well might be non-trivial, depending on your exact requirements.