audio

pi/roverd/tts.go

@@ -3,6 +3,7 @@ package roverd
 import (
 	"context"
 	"fmt"
+	"os"
 	"os/exec"
 	"strings"
 	"time"
@@ -47,29 +48,75 @@ func (c *WSClient) handleTTSPayload(ctx context.Context, payload *ttsPayload) er
 	runCtx, cancel := context.WithTimeout(ctx, 12*time.Second)
 	defer cancel()
 
+	tmp, err := os.CreateTemp("", "roverd-tts-*.wav")
+	if err != nil {
+		return fmt.Errorf("tts temp file: %w", err)
+	}
+	tmpPath := tmp.Name()
+	_ = tmp.Close()
+	defer os.Remove(tmpPath)
+
+	if err := synthTTS(runCtx, engine, voice, pitch, text, tmpPath); err != nil {
+		return err
+	}
+	if err := playTTSFile(runCtx, tmpPath, c.cfg.Audio.PlaybackDevice, c.getAudioLevels().TTSGain); err != nil {
+		return err
+	}
+	return nil
+}
+
+func synthTTS(ctx context.Context, engine, voice string, pitch int, text, outputWavPath string) error {
 	var cmd *exec.Cmd
 	switch engine {
 	case "espeak", "e":
-		args := []string{}
+		args := []string{"-w", outputWavPath}
 		if pitch > 0 {
 			args = append(args, "-p", fmt.Sprintf("%d", pitch))
 		}
 		args = append(args, text)
-		cmd = exec.CommandContext(runCtx, "espeak", args...)
+		cmd = exec.CommandContext(ctx, "espeak", args...)
 	case "flite", "f":
 		args := []string{}
 		if voice != "" {
 			args = append(args, "-voice", voice)
 		}
-		args = append(args, "-t", text)
-		cmd = exec.CommandContext(runCtx, "flite", args...)
+		args = append(args, "-t", text, "-o", outputWavPath)
+		cmd = exec.CommandContext(ctx, "flite", args...)
 	default:
 		return fmt.Errorf("unsupported tts engine: %s", engine)
 	}
 
 	out, err := cmd.CombinedOutput()
 	if err != nil {
-		return fmt.Errorf("tts exec failed: %w (%s)", err, string(out))
+		return fmt.Errorf("tts synth failed: %w (%s)", err, string(out))
+	}
+	return nil
+}
+
+func playTTSFile(ctx context.Context, wavPath, playbackDevice string, gain float64) error {
+	if playbackDevice == "" {
+		playbackDevice = "default"
+	}
+	gain = clampAudioGain(gain)
+	if gain == 0 {
+		// Mute is an explicit value users may choose.
+		return nil
+	}
+
+	args := []string{
+		"-hide_banner",
+		"-loglevel", "warning",
+		"-i", wavPath,
+		"-af", fmt.Sprintf("aresample=16000,volume=%g", gain),
+		"-ac", "1",
+		"-ar", "16000",
+		"-f", "alsa",
+		playbackDevice,
+	}
+	cmd := exec.CommandContext(ctx, "ffmpeg", args...)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("tts playback failed: %w (%s)", err, string(out))
 	}
 	return nil
 }