mod_sivr_asr
Designed to work with asrd | Manual
mod_google_asr
Google speech-to-text service (full featured, v1-api)
Opensource version and examples | Manual
mod_openai_asr
OpenAI speech-to-text service (full featured, v1-api)
Opensource version and examples | Manual

mod_sivr_asr | mod_google_asr | mod_openai_asr

Feature	Commercial
Supported audio channels	*
Voice activity detection (Advanced VAD)	+
Voice features extraction ( ivectors )	+
Auto gain control (AGC)	+
Speech start timeout timer	+
Results in json with extra info (audio chunk, duration, etc)	+
Returning service errors	+
Keeping audio chunks	+
Source code	-
Price	$950

Feature	Opensource	Commercial
Supported audio channels	1	*
Voice activity detection (VAD)	+	+
Auto gain control (AGC)	-	+
Speech start timeout timer	-	+
Results in json with extra info (audio chunk, duration, etc)	-	+
Returning service errors	-	+
Keeping audio chunks	-	+
Voice features protection (complicates speaker identification)	-	-
Flexible HTTP settings (proxy/timeouts/etc...)	+	+
Source code	+	-
Price	free	$250

Feature	Opensource	Commercial
Supported audio channels	1	*
Voice activity detection (VAD)	+	+
Auto gain control (AGC)	-	+
Flexible HTTP settings (proxy/timeouts/etc...)	+	+
Speech start timeout timer	-	+
Results in json with extra info (audio chunk, duration, etc)	-	+
Returning service errors	-	+
Keeping audio chunks	-	+
Voice features protection (complicates speaker identification)	-	-
Flexible HTTP settings (proxy/timeouts/etc...)	+	+
Source code	+	-
Price	free	$250