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// 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.
#include <string.h>
#include <algorithm>
#include <limits>
#include "ppapi/cpp/audio_config.h"
#include "ppapi/cpp/dev/audio_input_dev.h"
#include "ppapi/cpp/graphics_2d.h"
#include "ppapi/cpp/image_data.h"
#include "ppapi/cpp/instance.h"
#include "ppapi/cpp/logging.h"
#include "ppapi/cpp/module.h"
#include "ppapi/cpp/rect.h"
#include "ppapi/cpp/size.h"
#include "ppapi/utility/completion_callback_factory.h"
class MyInstance : public pp::Instance {
public:
explicit MyInstance(PP_Instance instance)
: pp::Instance(instance),
callback_factory_(this),
sample_count_(0),
channel_count_(0),
samples_(NULL),
timer_interval_(0),
pending_paint_(false),
waiting_for_flush_completion_(false) {
}
virtual ~MyInstance() {
audio_input_.StopCapture();
delete[] samples_;
}
virtual bool Init(uint32_t argc, const char* argn[], const char* argv[]) {
// This sample frequency is guaranteed to work.
const PP_AudioSampleRate kSampleFrequency = PP_AUDIOSAMPLERATE_44100;
const uint32_t kSampleCount = 1024;
const uint32_t kChannelCount = 1;
sample_count_ = pp::AudioConfig::RecommendSampleFrameCount(this,
kSampleFrequency,
kSampleCount);
PP_DCHECK(sample_count_ > 0);
channel_count_ = kChannelCount;
pp::AudioConfig config = pp::AudioConfig(this,
kSampleFrequency,
sample_count_);
samples_ = new int16_t[sample_count_ * channel_count_];
memset(samples_, 0, sample_count_ * channel_count_ * sizeof(int16_t));
audio_input_ = pp::AudioInput_Dev(this, config, CaptureCallback, this);
if (!audio_input_.StartCapture())
return false;
// Try to ensure that we pick up a new set of samples between each
// timer-generated repaint.
timer_interval_ = (sample_count_ * 1000) / kSampleFrequency + 5;
ScheduleNextTimer();
return true;
}
virtual void DidChangeView(const pp::Rect& position, const pp::Rect& clip) {
if (position.size() == size_)
return;
size_ = position.size();
device_context_ = pp::Graphics2D(this, size_, false);
if (!BindGraphics(device_context_))
return;
Paint();
}
private:
void ScheduleNextTimer() {
PP_DCHECK(timer_interval_ > 0);
pp::Module::Get()->core()->CallOnMainThread(
timer_interval_,
callback_factory_.NewRequiredCallback(&MyInstance::OnTimer),
0);
}
void OnTimer(int32_t) {
ScheduleNextTimer();
Paint();
}
void DidFlush(int32_t result) {
waiting_for_flush_completion_ = false;
if (pending_paint_)
Paint();
}
void Paint() {
if (waiting_for_flush_completion_) {
pending_paint_ = true;
return;
}
pending_paint_ = false;
if (size_.IsEmpty())
return; // Nothing to do.
pp::ImageData image = PaintImage(size_);
if (!image.is_null()) {
device_context_.ReplaceContents(&image);
waiting_for_flush_completion_ = true;
device_context_.Flush(
callback_factory_.NewRequiredCallback(&MyInstance::DidFlush));
}
}
pp::ImageData PaintImage(const pp::Size& size) {
pp::ImageData image(this, PP_IMAGEDATAFORMAT_BGRA_PREMUL, size, false);
if (image.is_null())
return image;
// Clear to dark grey.
for (int y = 0; y < size.height(); y++) {
for (int x = 0; x < size.width(); x++)
*image.GetAddr32(pp::Point(x, y)) = 0xff202020;
}
int mid_height = size.height() / 2;
int max_amplitude = size.height() * 4 / 10;
// Draw some lines.
for (int x = 0; x < size.width(); x++) {
*image.GetAddr32(pp::Point(x, mid_height)) = 0xff606060;
*image.GetAddr32(pp::Point(x, mid_height + max_amplitude)) = 0xff404040;
*image.GetAddr32(pp::Point(x, mid_height - max_amplitude)) = 0xff404040;
}
// Draw our samples.
for (int x = 0, i = 0;
x < std::min(size.width(), static_cast<int>(sample_count_));
x++, i += channel_count_) {
int y = samples_[i] * max_amplitude /
(std::numeric_limits<int16_t>::max() + 1) + mid_height;
*image.GetAddr32(pp::Point(x, y)) = 0xffffffff;
}
return image;
}
// TODO(viettrungluu): Danger! We really should lock, but which thread
// primitives to use? In any case, the |StopCapture()| in the destructor
// shouldn't return until this callback is done, so at least we should be
// writing to a valid region of memory.
static void CaptureCallback(const void* samples,
uint32_t num_bytes,
void* ctx) {
MyInstance* thiz = static_cast<MyInstance*>(ctx);
PP_DCHECK(num_bytes ==
thiz->sample_count_ * thiz->channel_count_ * sizeof(int16_t));
memcpy(thiz->samples_, samples, num_bytes);
}
pp::CompletionCallbackFactory<MyInstance> callback_factory_;
uint32_t sample_count_;
uint32_t channel_count_;
int16_t* samples_;
int32_t timer_interval_;
// Painting stuff.
pp::Size size_;
pp::Graphics2D device_context_;
bool pending_paint_;
bool waiting_for_flush_completion_;
pp::AudioInput_Dev audio_input_;
};
class MyModule : public pp::Module {
public:
virtual pp::Instance* CreateInstance(PP_Instance instance) {
return new MyInstance(instance);
}
};
namespace pp {
// Factory function for your specialization of the Module object.
Module* CreateModule() {
return new MyModule();
}
} // namespace pp
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