An idiomatic C++ client library for theCloud Speech-to-Text API, a service which converts audio to text by applying powerful neural network models.
While this library isGA, please note Google Cloud C++ client libraries donotfollowSemantic Versioning.
Quickstart
The following shows the code that you'll run in thegoogle/cloud/speech/quickstart/directory, which should give you a taste of the Cloud Speech-to-Text API C++ client library API.
#include "google/cloud/speech/v1/speech_client.h"
#include "google/cloud/project.h"
#include <iostream>
int main(int argc, char* argv[]) try {
auto constexpr kDefaultUri = "gs://cloud-samples-data/speech/hello.wav";
if (argc > 2) {
std::cerr << "Usage: " << argv[0] << " [gcs-uri]\n"
<< " The gcs-uri must be in gs://... format. It defaults to "
<< kDefaultUri << "\n";
return 1;
}
auto uri = std::string{argc == 2 ? argv[1] : kDefaultUri};
namespace speech = ::google::cloud::speech_v1;
auto client = speech::SpeechClient(speech::MakeSpeechConnection());
google::cloud::speech::v1::RecognitionConfig config;
config.set_language_code("en-US");
google::cloud::speech::v1::RecognitionAudio audio;
audio.set_uri(uri);
auto response = client.Recognize(config, audio);
if (!response) throw std::move(response).status();
std::cout << response->DebugString() << "\n";
return 0;
} catch (google::cloud::Status const& status) {
std::cerr << "google::cloud::Status thrown: " << status << "\n";
return 1;
}
Main classes
This library offers multiple*Clientclasses, which are listed below. Each one of these classes exposes all the RPCs for a service as member functions of the class. This library groups multiple services because they are part of the same product or are often used together. A typical example may be the administrative and data plane operations for a single product.
The library also has other classes that provide helpers, configuration parameters, and infrastructure to mock the*Clientclasses when testing your application.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThis webpage provides documentation for the Cloud Speech-to-Text API C++ client library, which facilitates converting audio to text using neural network models.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release candidate version for the C++ library is 2.37.0-rc, with a comprehensive list of previous versions available, including version 2.19.0 which is the current version in scope for the provided documentation.\u003c/p\u003e\n"],["\u003cp\u003eThe library includes \u003ccode\u003e*Client\u003c/code\u003e classes like \u003ccode\u003eAdaptationClient\u003c/code\u003e, and \u003ccode\u003eSpeechClient\u003c/code\u003e for different services, enabling developers to use these as member functions for the remote procedure calls (RPCs).\u003c/p\u003e\n"],["\u003cp\u003eThe library offers resources on error handling, endpoint overrides, authentication credential overrides, retry policies, and configurable environment variables to assist users in customizing their implementation.\u003c/p\u003e\n"],["\u003cp\u003eThe Cloud Speech C++ client library does not use semantic versioning, and a code snippet is provided for quick start implementation.\u003c/p\u003e\n"]]],[],null,["Version 2.19.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/speech/latest)\n- [2.41.0](/cpp/docs/reference/speech/2.41.0)\n- [2.40.0](/cpp/docs/reference/speech/2.40.0)\n- [2.39.0](/cpp/docs/reference/speech/2.39.0)\n- [2.38.0](/cpp/docs/reference/speech/2.38.0)\n- [2.37.0](/cpp/docs/reference/speech/2.37.0)\n- [2.36.0](/cpp/docs/reference/speech/2.36.0)\n- [2.35.0](/cpp/docs/reference/speech/2.35.0)\n- [2.34.0](/cpp/docs/reference/speech/2.34.0)\n- [2.33.0](/cpp/docs/reference/speech/2.33.0)\n- [2.32.0](/cpp/docs/reference/speech/2.32.0)\n- [2.31.0](/cpp/docs/reference/speech/2.31.0)\n- [2.30.0](/cpp/docs/reference/speech/2.30.0)\n- [2.29.0](/cpp/docs/reference/speech/2.29.0)\n- [2.28.0](/cpp/docs/reference/speech/2.28.0)\n- [2.27.0](/cpp/docs/reference/speech/2.27.0)\n- [2.26.0](/cpp/docs/reference/speech/2.26.0)\n- [2.25.1](/cpp/docs/reference/speech/2.25.1)\n- [2.24.0](/cpp/docs/reference/speech/2.24.0)\n- [2.23.0](/cpp/docs/reference/speech/2.23.0)\n- [2.22.1](/cpp/docs/reference/speech/2.22.1)\n- [2.21.0](/cpp/docs/reference/speech/2.21.0)\n- [2.20.0](/cpp/docs/reference/speech/2.20.0)\n- [2.19.0](/cpp/docs/reference/speech/2.19.0)\n- [2.18.0](/cpp/docs/reference/speech/2.18.0)\n- [2.17.0](/cpp/docs/reference/speech/2.17.0)\n- [2.16.0](/cpp/docs/reference/speech/2.16.0)\n- [2.15.1](/cpp/docs/reference/speech/2.15.1)\n- [2.14.0](/cpp/docs/reference/speech/2.14.0)\n- [2.13.0](/cpp/docs/reference/speech/2.13.0)\n- [2.12.0](/cpp/docs/reference/speech/2.12.0)\n- [2.11.0](/cpp/docs/reference/speech/2.11.0) \n\nCloud Speech-to-Text API C++ Client Library\n===========================================\n\nAn idiomatic C++ client library for the [Cloud Speech-to-Text API](https://cloud.google.com/speech), a service which converts audio to text by applying powerful neural network models.\n\nWhile this library is **GA** , please note Google Cloud C++ client libraries do **not** follow [Semantic Versioning](https://semver.org/).\n\n### Quickstart\n\nThe following shows the code that you'll run in the `google/cloud/speech/quickstart/` directory, which should give you a taste of the Cloud Speech-to-Text API C++ client library API. \n\n #include \"google/cloud/speech/v1/speech_client.h\"\n #include \"google/cloud/project.h\"\n #include \u003ciostream\u003e\n\n int main(int argc, char* argv[]) try {\n auto constexpr kDefaultUri = \"gs://cloud-samples-data/speech/hello.wav\";\n if (argc \u003e 2) {\n std::cerr \u003c\u003c \"Usage: \" \u003c\u003c argv[0] \u003c\u003c \" [gcs-uri]\\n\"\n \u003c\u003c \" The gcs-uri must be in gs://... format. It defaults to \"\n \u003c\u003c kDefaultUri \u003c\u003c \"\\n\";\n return 1;\n }\n auto uri = std::string{argc == 2 ? argv[1] : kDefaultUri};\n\n namespace speech = ::google::cloud::speech_v1;\n auto client = speech::SpeechClient(speech::MakeSpeechConnection());\n\n google::cloud::speech::v1::RecognitionConfig config;\n config.set_language_code(\"en-US\");\n google::cloud::speech::v1::RecognitionAudio audio;\n audio.set_uri(uri);\n auto response = client.Recognize(config, audio);\n if (!response) throw std::move(response).status();\n std::cout \u003c\u003c response-\u003eDebugString() \u003c\u003c \"\\n\";\n\n return 0;\n } catch (google::cloud::Status const& status) {\n std::cerr \u003c\u003c \"google::cloud::Status thrown: \" \u003c\u003c status \u003c\u003c \"\\n\";\n return 1;\n }\n\n### Main classes\n\nThis library offers multiple `*Client` classes, which are listed below. Each one of these classes exposes all the RPCs for a service as member functions of the class. This library groups multiple services because they are part of the same product or are often used together. A typical example may be the administrative and data plane operations for a single product.\n\nThe library also has other classes that provide helpers, configuration parameters, and infrastructure to mock the `*Client` classes when testing your application.\n\n- [`speech_v1::AdaptationClient`](/cpp/docs/reference/speech/2.19.0/classgoogle_1_1cloud_1_1speech__v1_1_1AdaptationClient)\n- [`speech_v1::SpeechClient`](/cpp/docs/reference/speech/2.19.0/classgoogle_1_1cloud_1_1speech__v1_1_1SpeechClient)\n- [`speech_v2::SpeechClient`](/cpp/docs/reference/speech/2.19.0/classgoogle_1_1cloud_1_1speech__v2_1_1SpeechClient)\n\n### More Information\n\n- [Error Handling](https://cloud.google.com/cpp/docs/reference/common/latest/common-error-handling.html) - describes how the library reports errors.\n- [How to Override the Default Endpoint](/cpp/docs/reference/speech/2.19.0/speech-override-endpoint) - describes how to override the default endpoint.\n- [How to Override the Authentication Credentials](/cpp/docs/reference/speech/2.19.0/speech-override-authentication) - describes how to change the authentication credentials used by the library.\n- [Override Retry, Backoff, and Idempotency Policies](/cpp/docs/reference/speech/2.19.0/speech-override-retry) - describes how to change the default retry policies.\n- [Environment Variables](/cpp/docs/reference/speech/2.19.0/speech-env) - describes environment variables that can configure the behavior of the library."]]