ppapi: implement PPB_AudioEncoder

content/renderer/pepper/audio_encoder_shim.h

+// Copyright 2015 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_RENDERER_PEPPER_AUDIO_ENCODER_SHIM_H_
+#define CONTENT_RENDERER_PEPPER_AUDIO_ENCODER_SHIM_H_
+
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+
+struct PP_AudioProfileDescription;
+
+namespace base {
+class SingleThreadTaskRunner;
+}  // namespace base
+
+namespace ppapi {
+namespace proxy {
+struct PPB_AudioEncodeParameters;
+}  // namespace proxy
+}  // namespace ppapi
+
+namespace content {
+
+// This class should be constructed, used, and destructed on the main
+// (render) thread.
+class AudioEncoderShim {
+ public:
+  // Class used to pass data between the different threads.
+  class AudioData : public base::RefCountedThreadSafe<AudioData> {
+   public:
+   virtual uint8_t* GetData() = 0;
+    virtual size_t GetSize() = 0;
+
+   protected:
+    AudioData() {}
+    virtual ~AudioData() {}
+
+   private:
+    friend class base::RefCountedThreadSafe<AudioData>;
+
+    DISALLOW_COPY_AND_ASSIGN(AudioData);
+  };
+
+  // Callback to signal encoded data. If |size| is negative, an error
+  // occured.
+  typedef base::Callback<void(const scoped_refptr<AudioData>& output,
+                              int32_t size)> BitstreamBufferReadyCB;
+
+  AudioEncoderShim();
+  ~AudioEncoderShim();
+
+  std::vector<PP_AudioProfileDescription> GetSupportedProfiles();
+  bool Initialize(const ppapi::proxy::PPB_AudioEncodeParameters& parameters);
+  int32_t GetNumberOfSamplesPerFrame();
+  void Encode(const scoped_refptr<AudioData>& input,
+              const scoped_refptr<AudioData>& output,
+              BitstreamBufferReadyCB callback);
+  void RequestBitrateChange(uint32_t bitrate);
+
+ private:
+  class EncoderImpl;
+  class OpusEncoderImpl;
+  class SpeexEncoderImpl;
+
+  void OnEncodeDone(const scoped_refptr<AudioData>& output,
+                    int32_t output_size,
+                    BitstreamBufferReadyCB callback);
+
+  scoped_ptr<EncoderImpl> encoder_impl_;
+
+  // Task doing the encoding.
+  scoped_refptr<base::SingleThreadTaskRunner> media_task_runner_;
+
+  base::WeakPtrFactory<AudioEncoderShim> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(AudioEncoderShim);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_PEPPER_VIDEO_ENCODER_SHIM_H_