It is stored in a text file as a stream of 'r' and 'c' characters - render and capture.
This is the format output by APM with apm_debug_dump on, and it is readable by audioproc_f.
Bug: webrtc:9252
Change-Id: I01e9e104ed7e3fb45e623730343a0c2addc81d1b
Reviewed-on: https://webrtc-review.googlesource.com/75502
Reviewed-by: Oleh Prypin <oprypin@webrtc.org>
Reviewed-by: Alex Loiko <aleloi@webrtc.org>
Commit-Queue: Sam Zackrisson <saza@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23213}