content/browser/speech/google_one_shot_remote_engine.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_SPEECH_GOOGLE_ONE_SHOT_REMOTE_ENGINE_H_
   6 #define CONTENT_BROWSER_SPEECH_GOOGLE_ONE_SHOT_REMOTE_ENGINE_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "content/browser/speech/audio_encoder.h"
  14 #include "content/browser/speech/speech_recognition_engine.h"
  15 #include "content/common/content_export.h"
  16 #include "net/url_request/url_fetcher_delegate.h"
  17
  18 namespace net {
  19 class URLRequestContextGetter;
  20 }
  21
  22 namespace content {
  23
  24 // Implements a SpeechRecognitionEngine by means of remote interaction with
  25 // Google speech recognition webservice.
  26 class CONTENT_EXPORT GoogleOneShotRemoteEngine
  27     : public NON_EXPORTED_BASE(SpeechRecognitionEngine),
  28       public net::URLFetcherDelegate {
  29  public:
  30   // Duration of each audio packet.
  31   static const int kAudioPacketIntervalMs;
  32   // ID passed to URLFetcher::Create(). Used for testing.
  33   static int url_fetcher_id_for_tests;
  34
  35   explicit GoogleOneShotRemoteEngine(net::URLRequestContextGetter* context);
  36   virtual ~GoogleOneShotRemoteEngine();
  37
  38   // SpeechRecognitionEngine methods.
  39   virtual void SetConfig(const SpeechRecognitionEngineConfig& config) OVERRIDE;
  40   virtual void StartRecognition() OVERRIDE;
  41   virtual void EndRecognition() OVERRIDE;
  42   virtual void TakeAudioChunk(const AudioChunk& data) OVERRIDE;
  43   virtual void AudioChunksEnded() OVERRIDE;
  44   virtual bool IsRecognitionPending() const OVERRIDE;
  45   virtual int GetDesiredAudioChunkDurationMs() const OVERRIDE;
  46
  47   // net::URLFetcherDelegate methods.
  48   virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
  49
  50  private:
  51   SpeechRecognitionEngineConfig config_;
  52   scoped_ptr<net::URLFetcher> url_fetcher_;
  53   scoped_refptr<net::URLRequestContextGetter> url_context_;
  54   scoped_ptr<AudioEncoder> encoder_;
  55
  56   DISALLOW_COPY_AND_ASSIGN(GoogleOneShotRemoteEngine);
  57 };
  58
  59 }  // namespace content
  60
  61 #endif  // CONTENT_BROWSER_SPEECH_GOOGLE_ONE_SHOT_REMOTE_ENGINE_H_