Pepper: Add latency calculation to ppapi/examples/video_decode.

ppapi/examples/video_decode/video_decode.cc

 // 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 <stdio.h>
 #include <string.h>
 
 #include <iostream>
 #include <queue>
 #include <sstream>
@@ skipping 141 matching lines @@
   Decoder(MyInstance* instance, int id, const pp::Graphics3D& graphics_3d);
   ~Decoder();
 
   int id() const { return id_; }
   bool flushing() const { return flushing_; }
   bool resetting() const { return resetting_; }
 
   void Reset();
   void RecyclePicture(const PP_VideoPicture& picture);
 
+  PP_TimeTicks GetAverageLatency() {
+    return num_pictures_ ? total_latency_ / num_pictures_ : 0;
+  }
+
  private:
   void InitializeDone(int32_t result);
   void Start();
   void DecodeNextFrame();
   void DecodeDone(int32_t result);
   void PictureReady(int32_t result, PP_VideoPicture picture);
   void FlushDone(int32_t result);
   void ResetDone(int32_t result);
 
   MyInstance* instance_;
   int id_;
 
   pp::VideoDecoder* decoder_;
   pp::CompletionCallbackFactory<Decoder> callback_factory_;
 
   size_t encoded_data_next_pos_to_decode_;
   int next_picture_id_;
   bool flushing_;
   bool resetting_;
+
+  const PPB_Core* core_if_;
+  static const int kMaxDecodeDelay = 128;
+  PP_TimeTicks decode_time_[kMaxDecodeDelay];
+  PP_TimeTicks total_latency_;
+  int num_pictures_;
 };
 
 #if defined USE_VP8_TESTDATA_INSTEAD_OF_H264
 
 // VP8 is stored in an IVF container.
 // Helpful description: http://wiki.multimedia.cx/index.php?title=IVF
 
 static void GetNextFrame(size_t* start_pos, size_t* end_pos) {
   size_t current_pos = *start_pos;
   if (current_pos == 0)
@@ skipping 29 matching lines @@
 Decoder::Decoder(MyInstance* instance,
                  int id,
                  const pp::Graphics3D& graphics_3d)
     : instance_(instance),
       id_(id),
       decoder_(new pp::VideoDecoder(instance)),
       callback_factory_(this),
       encoded_data_next_pos_to_decode_(0),
       next_picture_id_(0),
       flushing_(false),
-      resetting_(false) {
+      resetting_(false),
+      total_latency_(0.0),
+      num_pictures_(0) {
+  core_if_ = static_cast<const PPB_Core*>(
+      pp::Module::Get()->GetBrowserInterface(PPB_CORE_INTERFACE));
+
 #if defined USE_VP8_TESTDATA_INSTEAD_OF_H264
   const PP_VideoProfile kBitstreamProfile = PP_VIDEOPROFILE_VP8MAIN;
 #else
   const PP_VideoProfile kBitstreamProfile = PP_VIDEOPROFILE_H264MAIN;
 #endif
 
   assert(!decoder_->is_null());
   decoder_->Initialize(graphics_3d,
                        kBitstreamProfile,
                        PP_TRUE /* allow_software_fallback */,
@@ skipping 47 matching lines @@
     }
 
     // Find the start of the next frame.
     size_t start_pos = encoded_data_next_pos_to_decode_;
     size_t end_pos;
     GetNextFrame(&start_pos, &end_pos);
     encoded_data_next_pos_to_decode_ = end_pos;
     // Decode the frame. On completion, DecodeDone will call DecodeNextFrame
     // to implement a decode loop.
     uint32_t size = static_cast<uint32_t>(end_pos - start_pos);
+    decode_time_[next_picture_id_ % kMaxDecodeDelay] = core_if_->GetTimeTicks();
     decoder_->Decode(next_picture_id_++,
                      size,
                      kData + start_pos,
                      callback_factory_.NewCallback(&Decoder::DecodeDone));
   }
 }
 
 void Decoder::DecodeDone(int32_t result) {
   assert(decoder_);
   // Break out of the decode loop on abort.
   if (result == PP_ERROR_ABORTED)
     return;
   assert(result == PP_OK);
   if (!flushing_ && !resetting_)
     DecodeNextFrame();
 }
 
 void Decoder::PictureReady(int32_t result, PP_VideoPicture picture) {
   assert(decoder_);
   // Break out of the get picture loop on abort.
   if (result == PP_ERROR_ABORTED)
     return;
   assert(result == PP_OK);
+
+  num_pictures_++;
+  PP_TimeTicks latency = core_if_->GetTimeTicks() -
+                         decode_time_[picture.decode_id % kMaxDecodeDelay];
+  total_latency_ += latency;
+
   decoder_->GetPicture(
       callback_factory_.NewCallbackWithOutput(&Decoder::PictureReady));
   instance_->PaintPicture(this, picture);
 }
 
 void Decoder::FlushDone(int32_t result) {
   assert(decoder_);
   assert(result == PP_OK || result == PP_ERROR_ABORTED);
   assert(flushing_);
   flushing_ = false;
@@ skipping 11 matching lines @@
 MyInstance::MyInstance(PP_Instance instance, pp::Module* module)
     : pp::Instance(instance),
       pp::Graphics3DClient(this),
       is_painting_(false),
       num_frames_rendered_(0),
       first_frame_delivered_ticks_(-1),
       last_swap_request_ticks_(-1),
       swap_ticks_(0),
       callback_factory_(this),
       context_(NULL) {
-  assert((console_if_ = static_cast<const PPB_Console*>(
-              module->GetBrowserInterface(PPB_CONSOLE_INTERFACE))));
-  assert((core_if_ = static_cast<const PPB_Core*>(
-              module->GetBrowserInterface(PPB_CORE_INTERFACE))));
-  assert((gles2_if_ = static_cast<const PPB_OpenGLES2*>(
-              module->GetBrowserInterface(PPB_OPENGLES2_INTERFACE))));
+  console_if_ = static_cast<const PPB_Console*>(
+      pp::Module::Get()->GetBrowserInterface(PPB_CONSOLE_INTERFACE));
+  core_if_ = static_cast<const PPB_Core*>(
+      pp::Module::Get()->GetBrowserInterface(PPB_CORE_INTERFACE));
+  gles2_if_ = static_cast<const PPB_OpenGLES2*>(
+      pp::Module::Get()->GetBrowserInterface(PPB_OPENGLES2_INTERFACE));
+
   RequestInputEvents(PP_INPUTEVENT_CLASS_MOUSE);
 }
 
 MyInstance::~MyInstance() {
   if (!context_)
     return;
 
   PP_Resource graphics_3d = context_->pp_resource();
   if (shader_2d_.program)
     gles2_if_->DeleteProgram(graphics_3d, shader_2d_.program);
@@ skipping 112 matching lines @@
 
 void MyInstance::PaintFinished(int32_t result) {
   assert(result == PP_OK);
   swap_ticks_ += core_if_->GetTimeTicks() - last_swap_request_ticks_;
   is_painting_ = false;
   ++num_frames_rendered_;
   if (num_frames_rendered_ % 50 == 0) {
     double elapsed = core_if_->GetTimeTicks() - first_frame_delivered_ticks_;
     double fps = (elapsed > 0) ? num_frames_rendered_ / elapsed : 1000;
     double ms_per_swap = (swap_ticks_ * 1e3) / num_frames_rendered_;
+    double secs_average_latency = 0;
+    for (DecoderList::iterator it = video_decoders_.begin();
+         it != video_decoders_.end();
+         ++it)
+      secs_average_latency += (*it)->GetAverageLatency();
+    secs_average_latency /= video_decoders_.size();
+    double ms_average_latency = 1000 * secs_average_latency;
     LogError(this).s() << "Rendered frames: " << num_frames_rendered_
                        << ", fps: " << fps
-                       << ", with average ms/swap of: " << ms_per_swap;
+                       << ", with average ms/swap of: " << ms_per_swap
+                       << ", with average latency (ms) of: "
+                       << ms_average_latency;
   }
 
   // If the decoders were reset, this will be empty.
   if (pending_pictures_.empty())
     return;
 
   const PendingPicture& next = pending_pictures_.front();
   Decoder* decoder = next.decoder;
   const PP_VideoPicture& picture = next.picture;
   decoder->RecyclePicture(picture);
@@ skipping 32 matching lines @@
 
   assertNoGLError();
 
   CreateGLObjects();
 }
 
 void MyInstance::CreateGLObjects() {
   // Assign vertex positions and texture coordinates to buffers for use in
   // shader program.
   static const float kVertices[] = {
-      -1, 1, -1, -1, 1, 1, 1, -1,  // Position coordinates.
-      0,  1, 0,  0,  1, 1, 1, 0,   // Texture coordinates.
+      -1, -1, -1, 1, 1, -1, 1, 1,  // Position coordinates.
+      0,  1,  0,  0, 1, 1,  1, 0,  // Texture coordinates.
   };
 
   GLuint buffer;
   gles2_if_->GenBuffers(context_->pp_resource(), 1, &buffer);
   gles2_if_->BindBuffer(context_->pp_resource(), GL_ARRAY_BUFFER, buffer);
 
   gles2_if_->BufferData(context_->pp_resource(),
                         GL_ARRAY_BUFFER,
                         sizeof(kVertices),
                         kVertices,
@@ skipping 115 matching lines @@
 };
 
 }  // anonymous namespace
 
 namespace pp {
 // Factory function for your specialization of the Module object.
 Module* CreateModule() {
   return new MyModule();
 }
 }  // namespace pp