VideoCaptureHost

content/browser/renderer_host/video_capture_memory.cc

+// Copyright (c) 2011 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 "content/browser/renderer_host/video_capture_memory.h"
+
+#include "base/logging.h"
+#include "base/stl_util-inl.h"
+#include "media/video/capture/video_capture_color_conversion.h"
+
+// The number of TransportDIBs VideoCaptureMemory allocate.
+static const unsigned int kNoOfDIBS = 3;
+
+VideoCaptureMemory::VideoCaptureMemory(
+    VideoCaptureMemory::EventHandler* event_handler,
+    VCEntryId entry)
+    : event_handler_(*event_handler),
+      entry_id_(entry) {}
+
+VideoCaptureMemory::~VideoCaptureMemory() {
+  // Delete all TransportDIBs
+  STLDeleteContainerPairSecondPointers(owned_dibs_.begin(),
+                                       owned_dibs_.end());
+  owned_dibs_.clear();
+}
+
+VideoCaptureMemory::VCEntryId VideoCaptureMemory::entry_id() {
+  return entry_id_;
+}
+
+bool VideoCaptureMemory::AddTransportDIB(TransportDIB::Handle handle) {
+// Check if we own this handle
+  const bool own_dib = owned_dibs_.find(handle) != owned_dibs_.end();
+  if (!own_dib) {
+    return false;
+  }
+
+  lock_.Acquire();
+  free_dibs_.push_back(handle);
+  lock_.Release();
+  return true;
+}
+
+bool VideoCaptureMemory::ReadyToDelete() {
+  base::AutoLock lock(lock_);
+  return free_dibs_.size() == owned_dibs_.size();
+}
+
+void VideoCaptureMemory::OnIncomingCapturedFrame(const uint8* data,
+                                                 int length,
+                                                 base::Time timestamp) {
+  TransportDIB::Handle handle;
+  // Check if there is a TransportDIB to fill.
+  bool buffer_exist = false;
+  lock_.Acquire();
+  if (free_dibs_.size() > 0) {
+    handle = free_dibs_.back();
+    free_dibs_.pop_back();
+    buffer_exist = true;
+  }
+  lock_.Release();
+
+  if (!buffer_exist) {
+    return;
+  }
+
+  TransportDIB* dib = TransportDIB::Map(handle);
+  uint8* target = static_cast<uint8*> (dib->memory());
+  CHECK(dib->size() >= (unsigned int) (frame_info_.width*frame_info_.height*3) /
+                                       2);
+
+  // Do color conversion from the camera format to I420.
+  media::VideoCaptureColorConversion::ConvertToI420(frame_info_.color, data,
+                                                    frame_info_.width,
+                                                    frame_info_.height,
+                                                    target);
+  event_handler_.OnBufferReady(entry_id_, handle, timestamp);
+}
+
+void VideoCaptureMemory::OnError() {
+  event_handler_.OnError(entry_id_);
+}
+
+void VideoCaptureMemory::OnFrameInfo(
+    const media::VideoCaptureDevice::Capability& info) {
+  DCHECK(owned_dibs_.empty());
+  // Lock needed since the buffers are used in OnIncomingFrame.
+  // And we need to use it there in order to avoid memcpy of complete frames
+  lock_.Acquire();
+  const size_t needed_size = (info.width * info.height * 3) / 2;
+  for (unsigned int i = 0; i < kNoOfDIBS; ++i) {
+    TransportDIB* dib = TransportDIB::Create(needed_size, i);
+    if (!dib) {
+      break;
+    }
+    owned_dibs_.insert(std::make_pair(dib->handle(), dib));
+    free_dibs_.push_back(dib->handle());
+  }
+  frame_info_= info;
+  lock_.Release();
+
+  // Check that all Dibs where created
+  if (owned_dibs_.size() != kNoOfDIBS) {
+    event_handler_.OnError(entry_id_);
+  }
+  event_handler_.OnFrameInfo(entry_id_, info.width, info.height,
+                             info.frame_rate);
+}