Google Cloud Text-to-Speech example

tts.go

package main

// http://codegists.com/code/google-cloud-speech-example/

import (
        "cloud.google.com/go/texttospeech/apiv1"
        "context"
        flags "github.com/jessevdk/go-flags"
        texttospeechpb "google.golang.org/genproto/googleapis/cloud/texttospeech/v1"
        "io/ioutil"
        "log"
        "os"
)

type Options struct {
        // https://cloud.google.com/text-to-speech/docs/voices
        // "ja-JP-Wavenet-A" or "ja-JP-Standard-A" in Japan
        Voice string  `short:"v" long:"voice" description:"voice name" default:"ja-JP-Standard-A"`
        Lang  string  `short:"l" long:"lang" description:"language code" default:"ja-JP"`
        Rate  float64 `short:"r" long:"rate" description:"speaking rate" default:"1.0"`
        Out   string  `short:"o" long:"out" description:"output filename" default:"speech.mp3"`
}

func main() {
        var opts Options

        _, err := flags.Parse(&opts)
        if err != nil {
                log.Fatal(err)
        }

        bytes, err := ioutil.ReadAll(os.Stdin)
        if err != nil {
                log.Fatal(err)
        }

        ctx := context.Background()
        c, err := texttospeech.NewClient(ctx)
        if err != nil {
                log.Fatal(err)
        }
        req := &texttospeechpb.SynthesizeSpeechRequest{
                Input: &texttospeechpb.SynthesisInput{
                        InputSource: &texttospeechpb.SynthesisInput_Text{
                                Text: string(bytes),
                        },
                },
                Voice: &texttospeechpb.VoiceSelectionParams{
                        LanguageCode: opts.Lang,
                        Name:         opts.Voice,
                        // SsmlGender: 1,
                },
                AudioConfig: &texttospeechpb.AudioConfig{
                        AudioEncoding: texttospeechpb.AudioEncoding_MP3,
                        SpeakingRate:  opts.Rate,
                },
        }
        resp, err := c.SynthesizeSpeech(ctx, req)
        if err != nil {
                log.Fatal(err)
        }
        err = ioutil.WriteFile(opts.Out, resp.GetAudioContent(), 0644)
        if err != nil {
                log.Fatal(err)
        }
}