Introducing new data types and IPC messages for scripted JS speech recognition APIs (Speech CL2.0)

content/browser/speech/speech_recognition_engine.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_ENGINE_H_
 #define CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_ENGINE_H_
 #pragma once
 
 #include <string>
-#include <vector>
 
 #include "base/basictypes.h"
+#include "content/public/common/speech_recognition_grammar.h"
 
 namespace content {
 struct SpeechRecognitionResult;
 struct SpeechRecognitionError;
 }
 
 namespace speech {
 
 class AudioChunk;
 
 // This interface models the basic contract that a speech recognition engine,
 // either working locally or relying on a remote web-service, must obey.
 // The expected call sequence for exported methods is:
 // StartRecognition      Mandatory at beginning of SR.
 //   TakeAudioChunk      For every audio chunk pushed.
 //   AudioChunksEnded    Finalize the audio stream (omitted in case of errors).
 // EndRecognition        Mandatory at end of SR (even on errors).
-// No delegate callback is allowed before Initialize() or after Cleanup().
+// No delegate callbacks are allowed before StartRecognition or after
+// EndRecognition. If a recognition was started, the caller can free the
+// SpeechRecognitionEngine only after calling EndRecognition.
 class SpeechRecognitionEngine {
  public:
   // Interface for receiving callbacks from this object.
   class Delegate {
    public:
     // Called whenever a result is retrieved. It might be issued several times,
     // (e.g., in the case of continuous speech recognition engine
     // implementations).
     virtual void OnSpeechRecognitionEngineResult(
         const content::SpeechRecognitionResult& result) = 0;
     virtual void OnSpeechRecognitionEngineError(
         const content::SpeechRecognitionError& error) = 0;
 
    protected:
     virtual ~Delegate() {}
   };
 
+  // Remove engine configuration.
+  struct Config {
+    Config();
+    ~Config();
+
+    std::string language;
+    content::SpeechRecognitionGrammarArray grammars;
+    bool filter_profanities;
+    std::string hardware_info;
+    std::string origin_url;
+    int audio_sample_rate;
+    int audio_num_bits_per_sample;
+  };
+
   virtual ~SpeechRecognitionEngine() {}
 
+  // Set/change the recognition engine configuration. It is not allowed to call
+  // this function while a recognition is ongoing.
+  virtual void SetConfig(const Config& config) = 0;
+
   // Called when the speech recognition begins, before any TakeAudioChunk call.
   virtual void StartRecognition() = 0;
 
   // End any recognition activity and don't make any further callback.
   // Must be always called to close the corresponding StartRecognition call,
   // even in case of errors.
   // No further TakeAudioChunk/AudioChunksEnded calls are allowed after this.
   virtual void EndRecognition() = 0;
 
   // Push a chunk of uncompressed audio data, where the chunk length agrees with
@@ skipping 14 matching lines @@
   // set_delegate detached from constructor for lazy dependency injection.
   void set_delegate(Delegate* delegate) { delegate_ = delegate; }
 
  protected:
   Delegate* delegate() const { return delegate_; }
 
  private:
   Delegate* delegate_;
 };
 
-// This typedef is to workaround the issue with certain versions of
+// These typedefs are to workaround the issue with certain versions of
 // Visual Studio where it gets confused between multiple Delegate
-// classes and gives a C2500 error. (I saw this error on the try bots -
-// the workaround was not needed for my machine).
+// classes and gives a C2500 error.
 typedef SpeechRecognitionEngine::Delegate SpeechRecognitionEngineDelegate;
+typedef SpeechRecognitionEngine::Config SpeechRecognitionEngineConfig;
 
 }  // namespace speech
 
 #endif  // CONTENT_BROWSER_SPEECH_SPEECH_RECOGNITION_ENGINE_H_