[jprjr_]

For FLAC, latency is primarily driven by block size and the library's own internal buffering.

Using the API you can set the blocksize, but there's no manual flush function. The only way to flush output is to call the "finish" function, which as its name implies - marks the stream as finished.

I actually wrote my own FLAC encoder for this exact reason - https://github.com/jprjr/tflac - focused on latency over efficient compression.