text: <?php
  /**
   * Copyright 2018 Google Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /**
   * For instructions on how to run the samples:
   *
   * @see https://github.com/GoogleCloudPlatform/php-docs-samples/tree/master/texttospeech/README.md
   */
  
  // Include Google Cloud dependendencies using Composer
  require_once __DIR__ . '/../vendor/autoload.php';
  
  if (count($argv) != 1) {
      return print("Usage: php list_voices.php\n");
  }
  
  // [START tts_list_voices]
  use Google\Cloud\TextToSpeech\V1\TextToSpeechClient;
  
  // create client object
  $client = new TextToSpeechClient();
  
  // perform list voices request
  $response = $client->listVoices();
  $voices = $response->getVoices();
  
  foreach ($voices as $voice) {
      // display the voice's name. example: tpc-vocoded
      printf('Name: %s' . PHP_EOL, $voice->getName());
  
      // display the supported language codes for this voice. example: 'en-US'
      foreach ($voice->getLanguageCodes() as $languageCode) {
          printf('Supported language: %s' . PHP_EOL, $languageCode);
      }
  
      // SSML voice gender values from TextToSpeech\V1\SsmlVoiceGender
      $ssmlVoiceGender = ['SSML_VOICE_GENDER_UNSPECIFIED', 'MALE', 'FEMALE',
      'NEUTRAL'];
  
      // display the SSML voice gender
      $gender = $voice->getSsmlGender();
      printf('SSML voice gender: %s' . PHP_EOL, $ssmlVoiceGender[$gender]);
  
      // display the natural hertz rate for this voice
      printf('Natural Sample Rate Hertz: %d' . PHP_EOL,
          $voice->getNaturalSampleRateHertz());
  }
  
  $client->close();
  // [END tts_list_voices]
  