{

if (!defined('Grpc\STATUS_OK')) {

throw new \Exception('Install the grpc extension ' .

'(pecl install grpc)');

}

if (!class_exists('Google\Cloud\Speech\V1\SpeechGrpcClient')) {

throw new \Exception('Install the proto client PHP library ' .

'(composer require google/proto-client)');

}

if (!class_exists('Google\GAX\GrpcConstants')) {

throw new \Exception('Install the GAX library ' .

'(composer require google/gax)');

}

$speechClient = new SpeechClient();

try {

$config = new RecognitionConfig();

$config->setLanguageCode($languageCode);

$config->setSampleRateHertz($sampleRateHertz);

// encoding must be an enum, convert from string

$encodingEnum = constant(RecognitionConfig_AudioEncoding::class . '::' . $encoding);

$config->setEncoding($encodingEnum);

$strmConfig = new StreamingRecognitionConfig();

$strmConfig->setConfig($config);

$strmReq = new StreamingRecognizeRequest();

$strmReq->setStreamingConfig($strmConfig);

$strm = $speechClient->streamingRecognize();

$strm->write($strmReq);

$strmReq = new StreamingRecognizeRequest();

$f = fopen($audioFile, "rb");

$fsize = filesize($audioFile);

$bytes = fread($f, $fsize);

$strmReq->setAudioContent($bytes);

$strm->write($strmReq);

foreach ($strm->closeWriteAndReadAll() as $response) {

foreach ($response->getResults() as $result) {

foreach ($result->getAlternatives() as $alt) {

printf("Transcription: %s\n", $alt->getTranscript());

}

}

}

} finally {

$speechClient->close();

}