What's the standard way of reading and writing audio files on Android / Kotlin?

I am very confused. I've found plenty of posts that discuss this at some level, but they're all either giving a third party answer (someone's own implementation like https://medium.com/@rizveeredwan/working-with-wav-files-in-android-52e9500297e or https://stackoverflow.com/a/43569709/4959635 or https://gist.github.com/kmark/d8b1b01fb0d2febf5770) or using some Java class, of which I don't know how it's related to the Android SDK (https://stackoverflow.com/a/26598862/4959635, https://gist.github.com/niusounds/3e49013a8e942cdba3fbfe1c336b61fc, https://github.com/google/oboe/issues/548#issuecomment-502758633).

I cannot find a standard way from the Android documentation. Some answer said to use https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.io/java.io.-input-stream/read-bytes.html for reading, but I'm quite sure this doesn't parse the file header.

So what's the standard way of processing audio files on Android / Kotlin?

I'm already using dr_wav just fine on desktop, so I am actually thinking of just using that through NDK and maybe creating a wrapper to it.

CodePudding user response：

Well, there is no strict standard.

In production, you usually choose stable third party library or your company's reusable internal solution for this kind of tasks. You still can implement it yourself, but it will cost you time, since most likely the implementation will consist of hundreds of lines of code and you probably will just create another variation of existing solution which is present on the internet.

CodePudding user response：

Your use case is not clear from the question.

Assuming that you need to process raw audio data (PCM samples) - the standard way is to read the (compressed) input file using the MediaExtractor and decode the packets using the MediaCodec. Note that the documentation includes some example code.

The MediaCodec outputs ByteBuffers containing raw PCM samples. The binary format is described here.