Continue prototyping

audio/audio.go

@@ -0,0 +1,53 @@
+package audio
+
+import (
+	"os/exec"
+	"fmt"
+	"regexp"
+)
+
+
+type MicStreamConfig struct {
+	Format string
+	Device string
+	Encoding string
+	Bitrate int
+	Channels int
+}
+
+func StreamMic(config MicStreamConfig) *exec.Cmd {
+	cmd := exec.Command("ffmpeg", "-re",
+		"-f", config.Format,
+		"-i", config.Device,
+		"-f", config.Encoding,
+		"-ar", fmt.Sprintf("%d", config.Bitrate),
+		"-ac", fmt.Sprintf("%d", config.Channels),
+		"-",
+	)
+	return cmd
+}
+
+func GetMicDevice() (string, error) {
+	cmd := exec.Command("ffmpeg",
+		"-f", "avfoundation",
+		"-list_devices", "true",
+		"-i", "\"\"",
+	)
+	// ignore error, this ffmpeg command returns exit status 1
+	outputBytes, _ := cmd.CombinedOutput()
+	output := string(outputBytes)
+	parsedOutput := parseDeviceNumber(output)
+	if parsedOutput == "" {
+		return "", fmt.Errorf("Command: %s\nFailed to parse FFmpeg output:\n%s", cmd, output)
+	}
+	return parsedOutput, nil
+}
+
+func parseDeviceNumber(ffmpegOutput string) string {
+	re := regexp.MustCompile(`\[(\d)\].*?[Mm]icrophone`)
+	matches := re.FindStringSubmatch(ffmpegOutput)	
+	if (len(matches) == 2) {
+		return matches[1]
+	}
+	return ""
+}