[PPAPI] Add media stream video track example

ppapi/examples/media_stream_video/media_stream_video.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 2014 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 <stdlib.h>
-#include <string.h>
-
-#include <map>
-#include <vector>
-
-#include "ppapi/c/dev/ppb_video_capture_dev.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/c/ppb_opengles2.h"
-#include "ppapi/cpp/dev/buffer_dev.h"
-#include "ppapi/cpp/dev/device_ref_dev.h"
-#include "ppapi/cpp/dev/video_capture_dev.h"
-#include "ppapi/cpp/dev/video_capture_client_dev.h"
 #include "ppapi/cpp/completion_callback.h"
+#include "ppapi/cpp/dev/var_resource_dev.h"
+#include "ppapi/cpp/graphics_3d.h"
 #include "ppapi/cpp/graphics_3d_client.h"
-#include "ppapi/cpp/graphics_3d.h"
 #include "ppapi/cpp/instance.h"
+#include "ppapi/cpp/media_stream_video_track.h"
 #include "ppapi/cpp/module.h"
 #include "ppapi/cpp/rect.h"
 #include "ppapi/cpp/var.h"
+#include "ppapi/cpp/video_frame.h"
 #include "ppapi/lib/gl/include/GLES2/gl2.h"
 #include "ppapi/utility/completion_callback_factory.h"
 
 // When compiling natively on Windows, PostMessage can be #define-d to
 // something else.
 #ifdef PostMessage
 #undef PostMessage
 #endif
 
 // Assert |context_| isn't holding any GL Errors.  Done as a macro instead of a
 // function to preserve line number information in the failure message.
 #define AssertNoGLError() \
   PP_DCHECK(!gles2_if_->GetError(context_->pp_resource()));
 
 namespace {
 
-const char* const kDelimiter = "#__#";
-
 // This object is the global object representing this plugin library as long
 // as it is loaded.
-class VCDemoModule : public pp::Module {
+class MediaStreamVideoModule : public pp::Module {
  public:
-  VCDemoModule() : pp::Module() {}
-  virtual ~VCDemoModule() {}
+  MediaStreamVideoModule() : pp::Module() {}
+  virtual ~MediaStreamVideoModule() {}
 
   virtual pp::Instance* CreateInstance(PP_Instance instance);
 };
 
-class VCDemoInstance : public pp::Instance,
-                       public pp::Graphics3DClient,
-                       public pp::VideoCaptureClient_Dev {
+class MediaStreamVideoDemoInstance : public pp::Instance,
+                        public pp::Graphics3DClient {
  public:
-  VCDemoInstance(PP_Instance instance, pp::Module* module);
-  virtual ~VCDemoInstance();
+  MediaStreamVideoDemoInstance(PP_Instance instance, pp::Module* module);
+  virtual ~MediaStreamVideoDemoInstance();
 
   // pp::Instance implementation (see PPP_Instance).
   virtual void DidChangeView(const pp::Rect& position,
                              const pp::Rect& clip_ignored);
   virtual void HandleMessage(const pp::Var& message_data);
 
   // pp::Graphics3DClient implementation.
   virtual void Graphics3DContextLost() {
     InitGL();
     CreateYUVTextures();
     Render();
   }
 
-  virtual void OnDeviceInfo(PP_Resource resource,
-                            const PP_VideoCaptureDeviceInfo_Dev& info,
-                            const std::vector<pp::Buffer_Dev>& buffers) {
-    capture_info_ = info;
-    buffers_ = buffers;
-    CreateYUVTextures();
-  }
-
-  virtual void OnStatus(PP_Resource resource, uint32_t status) {
-  }
-
-  virtual void OnError(PP_Resource resource, uint32_t error) {
-  }
-
-  virtual void OnBufferReady(PP_Resource resource, uint32_t buffer) {
-    const char* data = static_cast<const char*>(buffers_[buffer].data());
-    int32_t width = capture_info_.width;
-    int32_t height = capture_info_.height;
-    gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE0);
-    gles2_if_->TexSubImage2D(
-        context_->pp_resource(), GL_TEXTURE_2D, 0, 0, 0, width, height,
-        GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
-
-    data += width * height;
-    width /= 2;
-    height /= 2;
-
-    gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE1);
-    gles2_if_->TexSubImage2D(
-        context_->pp_resource(), GL_TEXTURE_2D, 0, 0, 0, width, height,
-        GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
-
-    data += width * height;
-    gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE2);
-    gles2_if_->TexSubImage2D(
-        context_->pp_resource(), GL_TEXTURE_2D, 0, 0, 0, width, height,
-        GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
-
-    video_capture_.ReuseBuffer(buffer);
-    if (is_painting_)
-      needs_paint_ = true;
-    else
-      Render();
-  }
-
  private:
   void Render();
 
   // GL-related functions.
   void InitGL();
   GLuint CreateTexture(int32_t width, int32_t height, int unit);
   void CreateGLObjects();
   void CreateShader(GLuint program, GLenum type, const char* source, int size);
   void PaintFinished(int32_t result);
   void CreateYUVTextures();
 
-  void Open(const pp::DeviceRef_Dev& device);
-  void Stop();
-  void Start();
-  void EnumerateDevicesFinished(int32_t result,
-                                std::vector<pp::DeviceRef_Dev>& devices);
-  void OpenFinished(int32_t result);
-
-  static void MonitorDeviceChangeCallback(void* user_data,
-                                          uint32_t device_count,
-                                          const PP_Resource devices[]);
+  // Callback that is invoked when new frames are recevied.
+  void OnGetFrame(int32_t result, pp::VideoFrame frame);
 
   pp::Size position_size_;
   bool is_painting_;
   bool needs_paint_;
   GLuint texture_y_;
   GLuint texture_u_;
   GLuint texture_v_;
-  pp::VideoCapture_Dev video_capture_;
-  PP_VideoCaptureDeviceInfo_Dev capture_info_;
-  std::vector<pp::Buffer_Dev> buffers_;
-  pp::CompletionCallbackFactory<VCDemoInstance> callback_factory_;
+  pp::MediaStreamVideoTrack video_track_;
+  pp::CompletionCallbackFactory<MediaStreamVideoDemoInstance> callback_factory_;
 
   // Unowned pointers.
   const struct PPB_OpenGLES2* gles2_if_;
 
   // Owned data.
   pp::Graphics3D* context_;
 
-  std::vector<pp::DeviceRef_Dev> enumerate_devices_;
-  std::vector<pp::DeviceRef_Dev> monitor_devices_;
+  pp::Size frame_size_;
 };
 
-VCDemoInstance::VCDemoInstance(PP_Instance instance, pp::Module* module)
+MediaStreamVideoDemoInstance::MediaStreamVideoDemoInstance(
+    PP_Instance instance, pp::Module* module)
     : pp::Instance(instance),
       pp::Graphics3DClient(this),
-      pp::VideoCaptureClient_Dev(this),
       is_painting_(false),
       needs_paint_(false),
       texture_y_(0),
       texture_u_(0),
       texture_v_(0),
-      video_capture_(this),
       callback_factory_(this),
       context_(NULL) {
   gles2_if_ = static_cast<const struct PPB_OpenGLES2*>(
       module->GetBrowserInterface(PPB_OPENGLES2_INTERFACE));
   PP_DCHECK(gles2_if_);
-
-  capture_info_.width = 320;
-  capture_info_.height = 240;
-  capture_info_.frames_per_second = 30;
 }
 
-VCDemoInstance::~VCDemoInstance() {
-  video_capture_.MonitorDeviceChange(NULL, NULL);
+MediaStreamVideoDemoInstance::~MediaStreamVideoDemoInstance() {
   delete context_;
 }
 
-void VCDemoInstance::DidChangeView(
+void MediaStreamVideoDemoInstance::DidChangeView(
     const pp::Rect& position, const pp::Rect& clip_ignored) {
   if (position.width() == 0 || position.height() == 0)
     return;
   if (position.size() == position_size_)
     return;
 
   position_size_ = position.size();
 
   // Initialize graphics.
   InitGL();
-
   Render();
 }
 
-void VCDemoInstance::HandleMessage(const pp::Var& message_data) {
-  if (message_data.is_string()) {
-    std::string event = message_data.AsString();
-    if (event == "PageInitialized") {
-      int32_t result = video_capture_.MonitorDeviceChange(
-          &VCDemoInstance::MonitorDeviceChangeCallback, this);
-      if (result != PP_OK)
-        PostMessage(pp::Var("MonitorDeviceChangeFailed"));
+void MediaStreamVideoDemoInstance::HandleMessage(const pp::Var& var_message) {
+  if (!var_message.is_dictionary())
+    return;
+  pp::VarDictionary var_dictionary_message(var_message);
+  pp::Var var_track = var_dictionary_message.Get("track");
+  if (!var_track.is_resource())
+    return;
 
-      pp::CompletionCallbackWithOutput<std::vector<pp::DeviceRef_Dev> >
-          callback = callback_factory_.NewCallbackWithOutput(
-              &VCDemoInstance::EnumerateDevicesFinished);
-      result = video_capture_.EnumerateDevices(callback);
-      if (result != PP_OK_COMPLETIONPENDING)
-        PostMessage(pp::Var("EnumerationFailed"));
-    } else if (event == "UseDefault") {
-      Open(pp::DeviceRef_Dev());
-    } else if (event == "Stop") {
-      Stop();
-    } else if (event == "Start") {
-      Start();
-    } else if (event.find("Monitor:") == 0) {
-      std::string index_str = event.substr(strlen("Monitor:"));
-      int index = atoi(index_str.c_str());
-      if (index >= 0 && index < static_cast<int>(monitor_devices_.size()))
-        Open(monitor_devices_[index]);
-      else
-        PP_NOTREACHED();
-    } else if (event.find("Enumerate:") == 0) {
-      std::string index_str = event.substr(strlen("Enumerate:"));
-      int index = atoi(index_str.c_str());
-      if (index >= 0 && index < static_cast<int>(enumerate_devices_.size()))
-        Open(enumerate_devices_[index]);
-      else
-        PP_NOTREACHED();
-    }
-  }
+  pp::Resource resource_track = pp::VarResource_Dev(var_track).AsResource();
+
+  video_track_ = pp::MediaStreamVideoTrack(resource_track);
+
+  video_track_.GetFrame(callback_factory_.NewCallbackWithOutput(
+        &MediaStreamVideoDemoInstance::OnGetFrame));
 }
 
-void VCDemoInstance::InitGL() {
+void MediaStreamVideoDemoInstance::InitGL() {
   PP_DCHECK(position_size_.width() && position_size_.height());
   is_painting_ = false;
 
   delete context_;
   int32_t attributes[] = {
     PP_GRAPHICS3DATTRIB_ALPHA_SIZE, 0,
     PP_GRAPHICS3DATTRIB_BLUE_SIZE, 8,
     PP_GRAPHICS3DATTRIB_GREEN_SIZE, 8,
     PP_GRAPHICS3DATTRIB_RED_SIZE, 8,
     PP_GRAPHICS3DATTRIB_DEPTH_SIZE, 0,
@@ skipping 12 matching lines @@
   gles2_if_->Clear(context_->pp_resource(), GL_COLOR_BUFFER_BIT);
   gles2_if_->Viewport(context_->pp_resource(), 0, 0,
                       position_size_.width(), position_size_.height());
 
   BindGraphics(*context_);
   AssertNoGLError();
 
   CreateGLObjects();
 }
 
-void VCDemoInstance::Render() {
+void MediaStreamVideoDemoInstance::Render() {
   PP_DCHECK(!is_painting_);
   is_painting_ = true;
   needs_paint_ = false;
   if (texture_y_) {
     gles2_if_->DrawArrays(context_->pp_resource(), GL_TRIANGLE_STRIP, 0, 4);
   } else {
     gles2_if_->Clear(context_->pp_resource(), GL_COLOR_BUFFER_BIT);
   }
   pp::CompletionCallback cb = callback_factory_.NewCallback(
-      &VCDemoInstance::PaintFinished);
+      &MediaStreamVideoDemoInstance::PaintFinished);
   context_->SwapBuffers(cb);
 }
 
-void VCDemoInstance::PaintFinished(int32_t result) {
+void MediaStreamVideoDemoInstance::PaintFinished(int32_t result) {
   is_painting_ = false;
   if (needs_paint_)
     Render();
 }
 
-GLuint VCDemoInstance::CreateTexture(int32_t width, int32_t height, int unit) {
+GLuint MediaStreamVideoDemoInstance::CreateTexture(
+    int32_t width, int32_t height, int unit) {
   GLuint texture_id;
   gles2_if_->GenTextures(context_->pp_resource(), 1, &texture_id);
   AssertNoGLError();
   // Assign parameters.
   gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE0 + unit);
   gles2_if_->BindTexture(context_->pp_resource(), GL_TEXTURE_2D, texture_id);
   gles2_if_->TexParameteri(
       context_->pp_resource(), GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
       GL_NEAREST);
   gles2_if_->TexParameteri(
       context_->pp_resource(), GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,
       GL_NEAREST);
   gles2_if_->TexParameterf(
       context_->pp_resource(), GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
       GL_CLAMP_TO_EDGE);
   gles2_if_->TexParameterf(
       context_->pp_resource(), GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,
       GL_CLAMP_TO_EDGE);
 
   // Allocate texture.
   gles2_if_->TexImage2D(
       context_->pp_resource(), GL_TEXTURE_2D, 0, GL_LUMINANCE, width, height, 0,
       GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
   AssertNoGLError();
   return texture_id;
 }
 
-void VCDemoInstance::CreateGLObjects() {
+void MediaStreamVideoDemoInstance::CreateGLObjects() {
   // Code and constants for shader.
   static const char kVertexShader[] =
       "varying vec2 v_texCoord;            \n"
       "attribute vec4 a_position;          \n"
       "attribute vec2 a_texCoord;          \n"
       "void main()                         \n"
       "{                                   \n"
       "    v_texCoord = a_texCoord;        \n"
       "    gl_Position = a_position;       \n"
       "}";
@@ skipping 64 matching lines @@
   gles2_if_->EnableVertexAttribArray(context, pos_location);
   gles2_if_->VertexAttribPointer(context, pos_location, 2,
                                  GL_FLOAT, GL_FALSE, 0, 0);
   gles2_if_->EnableVertexAttribArray(context, tc_location);
   gles2_if_->VertexAttribPointer(
       context, tc_location, 2, GL_FLOAT, GL_FALSE, 0,
       static_cast<float*>(0) + 8);  // Skip position coordinates.
   AssertNoGLError();
 }
 
-void VCDemoInstance::CreateShader(
+void MediaStreamVideoDemoInstance::CreateShader(
     GLuint program, GLenum type, const char* source, int size) {
   PP_Resource context = context_->pp_resource();
   GLuint shader = gles2_if_->CreateShader(context, type);
   gles2_if_->ShaderSource(context, shader, 1, &source, &size);
   gles2_if_->CompileShader(context, shader);
   gles2_if_->AttachShader(context, program, shader);
   gles2_if_->DeleteShader(context, shader);
 }
 
-void VCDemoInstance::CreateYUVTextures() {
-  int32_t width = capture_info_.width;
-  int32_t height = capture_info_.height;
+void MediaStreamVideoDemoInstance::CreateYUVTextures() {
+  int32_t width = frame_size_.width();
+  int32_t height = frame_size_.height();
+  if (width == 0 || height == 0)
+    return;
+  if (texture_y_)
+    gles2_if_->DeleteTextures(context_->pp_resource(), 1, &texture_y_);
+  if (texture_u_)
+    gles2_if_->DeleteTextures(context_->pp_resource(), 1, &texture_u_);
+  if (texture_v_)
+    gles2_if_->DeleteTextures(context_->pp_resource(), 1, &texture_v_);
   texture_y_ = CreateTexture(width, height, 0);
 
   width /= 2;
   height /= 2;
   texture_u_ = CreateTexture(width, height, 1);
   texture_v_ = CreateTexture(width, height, 2);
 }
 
-void VCDemoInstance::Open(const pp::DeviceRef_Dev& device) {
-  pp::CompletionCallback callback = callback_factory_.NewCallback(
-      &VCDemoInstance::OpenFinished);
-  int32_t result = video_capture_.Open(device, capture_info_, 4, callback);
-  if (result != PP_OK_COMPLETIONPENDING)
-    PostMessage(pp::Var("OpenFailed"));
+void MediaStreamVideoDemoInstance::OnGetFrame(
+    int32_t result, pp::VideoFrame frame) {
+  if (result != PP_OK)
+    return;
+  const char* data = static_cast<const char*>(frame.GetDataBuffer());
+  pp::Size size;
+  PP_DCHECK(frame.GetSize(&size));
+  if (size != frame_size_) {
+    frame_size_ = size;
+    CreateYUVTextures();
+  }
+
+  int32_t width = frame_size_.width();
+  int32_t height = frame_size_.height();
+  gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE0);
+  gles2_if_->TexSubImage2D(
+      context_->pp_resource(), GL_TEXTURE_2D, 0, 0, 0, width, height,
+      GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
+
+  data += width * height;
+  width /= 2;
+  height /= 2;
+
+  gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE1);
+  gles2_if_->TexSubImage2D(
+      context_->pp_resource(), GL_TEXTURE_2D, 0, 0, 0, width, height,
+      GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
+
+  data += width * height;
+  gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE2);
+  gles2_if_->TexSubImage2D(
+      context_->pp_resource(), GL_TEXTURE_2D, 0, 0, 0, width, height,
+      GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
+
+  if (is_painting_)
+    needs_paint_ = true;
+  else
+    Render();
+
+  video_track_.RecycleFrame(frame);
+  video_track_.GetFrame(callback_factory_.NewCallbackWithOutput(
+      &MediaStreamVideoDemoInstance::OnGetFrame));
 }
 
-void VCDemoInstance::Stop() {
-  if (video_capture_.StopCapture() != PP_OK)
-    PostMessage(pp::Var("StopFailed"));
-}
-
-void VCDemoInstance::Start() {
-  if (video_capture_.StartCapture() != PP_OK)
-    PostMessage(pp::Var("StartFailed"));
-}
-
-void VCDemoInstance::EnumerateDevicesFinished(
-    int32_t result,
-  std::vector<pp::DeviceRef_Dev>& devices) {
-  if (result == PP_OK) {
-    enumerate_devices_.swap(devices);
-    std::string device_names = "Enumerate:";
-    for (size_t index = 0; index < enumerate_devices_.size(); ++index) {
-      pp::Var name = enumerate_devices_[index].GetName();
-      PP_DCHECK(name.is_string());
-
-      if (index != 0)
-        device_names += kDelimiter;
-      device_names += name.AsString();
-    }
-    PostMessage(pp::Var(device_names));
-  } else {
-    PostMessage(pp::Var("EnumerationFailed"));
-  }
-}
-
-void VCDemoInstance::OpenFinished(int32_t result) {
-  if (result == PP_OK)
-    Start();
-  else
-    PostMessage(pp::Var("OpenFailed"));
-}
-
-// static
-void VCDemoInstance::MonitorDeviceChangeCallback(void* user_data,
-                                                 uint32_t device_count,
-                                                 const PP_Resource devices[]) {
-  VCDemoInstance* thiz = static_cast<VCDemoInstance*>(user_data);
-
-  std::string device_names = "Monitor:";
-  thiz->monitor_devices_.clear();
-  thiz->monitor_devices_.reserve(device_count);
-  for (size_t index = 0; index < device_count; ++index) {
-    thiz->monitor_devices_.push_back(pp::DeviceRef_Dev(devices[index]));
-    pp::Var name = thiz->monitor_devices_.back().GetName();
-    PP_DCHECK(name.is_string());
-
-    if (index != 0)
-      device_names += kDelimiter;
-    device_names += name.AsString();
-  }
-  thiz->PostMessage(pp::Var(device_names));
-}
-
-pp::Instance* VCDemoModule::CreateInstance(PP_Instance instance) {
-  return new VCDemoInstance(instance, this);
+pp::Instance* MediaStreamVideoModule::CreateInstance(PP_Instance instance) {
+  return new MediaStreamVideoDemoInstance(instance, this);
 }
 
 }  // anonymous namespace
 
 namespace pp {
 // Factory function for your specialization of the Module object.
 Module* CreateModule() {
-  return new VCDemoModule();
+  return new MediaStreamVideoModule();
 }
 }  // namespace pp