ADPCM was developed in the early 1970s at Bell Labs for voice coding, by P. Cummiskey, N. S. Jayant, and James L. Flanagan.
Recording via built-in microphone or FM radio in ADPCM WAV (32 kbit/s mono or 64k bps stereo; using FFmpeg codec named adpcm ima wav), ACT (8 kbit/s) or VOR (32 or 8 kbit/s) formats, and ability to play back these files locally or via Windows Media Player when connected as an MSC device.