media/base/fake_audio_render_callback.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 MEDIA_BASE_FAKE_AUDIO_RENDER_CALLBACK_H_
   6 #define MEDIA_BASE_FAKE_AUDIO_RENDER_CALLBACK_H_
   7
   8 #include "media/base/audio_renderer_sink.h"
   9 #include "testing/gmock/include/gmock/gmock.h"
  10
  11 namespace media {
  12
  13 // Fake RenderCallback which will fill each request with a sine wave.  Sine
  14 // state is kept across callbacks.  State can be reset to default via reset().
  15 class FakeAudioRenderCallback : public AudioRendererSink::RenderCallback {
  16  public:
  17   // The function used to fulfill Render() is f(x) = sin(2 * PI * x * |step|),
  18   // where x = [|number_of_frames| * m, |number_of_frames| * (m + 1)] and m =
  19   // the number of Render() calls fulfilled thus far.
  20   explicit FakeAudioRenderCallback(double step);
  21   virtual ~FakeAudioRenderCallback();
  22
  23   // Renders a sine wave into the provided audio data buffer.  If |half_fill_|
  24   // is set, will only fill half the buffer.
  25   int Render(AudioBus* audio_bus, int audio_delay_milliseconds) OVERRIDE;
  26   MOCK_METHOD0(OnRenderError, void());
  27
  28   // Toggles only filling half the requested amount during Render().
  29   void set_half_fill(bool half_fill) { half_fill_ = half_fill; }
  30
  31   // Reset the sine state to initial value.
  32   void reset() { x_ = 0; }
  33
  34   // Returns the last |audio_delay_milliseconds| provided to Render() or -1 if
  35   // no Render() call occurred.
  36   int last_audio_delay_milliseconds() { return last_audio_delay_milliseconds_; }
  37
  38  private:
  39   bool half_fill_;
  40   double x_;
  41   double step_;
  42   int last_audio_delay_milliseconds_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(FakeAudioRenderCallback);
  45 };
  46
  47 }  // namespace media
  48
  49 #endif  // MEDIA_BASE_FAKE_AUDIO_RENDER_CALLBACK_H_