content/browser/renderer_host/media/video_capture_controller.cc

   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 #include "content/browser/renderer_host/media/video_capture_controller.h"
   6
   7 #include <map>
   8 #include <set>
   9
  10 #include "base/bind.h"
  11 #include "base/debug/trace_event.h"
  12 #include "base/metrics/histogram.h"
  13 #include "base/metrics/sparse_histogram.h"
  14 #include "base/stl_util.h"
  15 #include "content/browser/renderer_host/media/media_stream_manager.h"
  16 #include "content/browser/renderer_host/media/video_capture_manager.h"
  17 #include "content/common/gpu/client/gl_helper.h"
  18 #include "content/public/browser/browser_thread.h"
  19 #include "gpu/command_buffer/common/mailbox_holder.h"
  20 #include "media/base/video_frame.h"
  21 #include "media/base/video_util.h"
  22 #include "media/base/yuv_convert.h"
  23 #include "third_party/libyuv/include/libyuv.h"
  24
  25 #if defined(OS_ANDROID)
  26 #include "content/browser/renderer_host/image_transport_factory_android.h"
  27 #else
  28 #include "content/browser/compositor/image_transport_factory.h"
  29 #endif
  30
  31 using media::VideoCaptureFormat;
  32
  33 namespace content {
  34
  35 namespace {
  36
  37 static const int kInfiniteRatio = 99999;
  38
  39 #define UMA_HISTOGRAM_ASPECT_RATIO(name, width, height) \
  40     UMA_HISTOGRAM_SPARSE_SLOWLY( \
  41         name, \
  42         (height) ? ((width) * 100) / (height) : kInfiniteRatio);
  43
  44 class PoolBuffer : public media::VideoCaptureDevice::Client::Buffer {
  45  public:
  46   PoolBuffer(const scoped_refptr<VideoCaptureBufferPool>& pool,
  47              int buffer_id,
  48              void* data,
  49              size_t size)
  50       : Buffer(buffer_id, data, size), pool_(pool) {
  51     DCHECK(pool_.get());
  52   }
  53
  54  private:
  55   virtual ~PoolBuffer() { pool_->RelinquishProducerReservation(id()); }
  56
  57   const scoped_refptr<VideoCaptureBufferPool> pool_;
  58 };
  59
  60 class SyncPointClientImpl : public media::VideoFrame::SyncPointClient {
  61  public:
  62   explicit SyncPointClientImpl(GLHelper* gl_helper) : gl_helper_(gl_helper) {}
  63   virtual ~SyncPointClientImpl() {}
  64   virtual uint32 InsertSyncPoint() OVERRIDE {
  65     return gl_helper_->InsertSyncPoint();
  66   }
  67   virtual void WaitSyncPoint(uint32 sync_point) OVERRIDE {
  68     gl_helper_->WaitSyncPoint(sync_point);
  69   }
  70
  71  private:
  72   GLHelper* gl_helper_;
  73 };
  74
  75 void ReturnVideoFrame(const scoped_refptr<media::VideoFrame>& video_frame,
  76                       uint32 sync_point) {
  77   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  78 #if defined(OS_ANDROID)
  79   GLHelper* gl_helper =
  80       ImageTransportFactoryAndroid::GetInstance()->GetGLHelper();
  81 #else
  82   GLHelper* gl_helper = ImageTransportFactory::GetInstance()->GetGLHelper();
  83 #endif
  84   DCHECK(gl_helper);
  85   // UpdateReleaseSyncPoint() creates a new sync_point using |gl_helper|, so
  86   // wait the given |sync_point| using |gl_helper|.
  87   gl_helper->WaitSyncPoint(sync_point);
  88   SyncPointClientImpl client(gl_helper);
  89   video_frame->UpdateReleaseSyncPoint(&client);
  90 }
  91
  92 }  // anonymous namespace
  93
  94 struct VideoCaptureController::ControllerClient {
  95   ControllerClient(const VideoCaptureControllerID& id,
  96                    VideoCaptureControllerEventHandler* handler,
  97                    base::ProcessHandle render_process,
  98                    media::VideoCaptureSessionId session_id,
  99                    const media::VideoCaptureParams& params)
 100       : controller_id(id),
 101         event_handler(handler),
 102         render_process_handle(render_process),
 103         session_id(session_id),
 104         parameters(params),
 105         session_closed(false) {}
 106
 107   ~ControllerClient() {}
 108
 109   // ID used for identifying this object.
 110   const VideoCaptureControllerID controller_id;
 111   VideoCaptureControllerEventHandler* const event_handler;
 112
 113   // Handle to the render process that will receive the capture buffers.
 114   const base::ProcessHandle render_process_handle;
 115   const media::VideoCaptureSessionId session_id;
 116   const media::VideoCaptureParams parameters;
 117
 118   // Buffers that are currently known to this client.
 119   std::set<int> known_buffers;
 120
 121   // Buffers currently held by this client, and syncpoint callback to call when
 122   // they are returned from the client.
 123   typedef std::map<int, scoped_refptr<media::VideoFrame> > ActiveBufferMap;
 124   ActiveBufferMap active_buffers;
 125
 126   // State of capture session, controlled by VideoCaptureManager directly. This
 127   // transitions to true as soon as StopSession() occurs, at which point the
 128   // client is sent an OnEnded() event. However, because the client retains a
 129   // VideoCaptureController* pointer, its ControllerClient entry lives on until
 130   // it unregisters itself via RemoveClient(), which may happen asynchronously.
 131   //
 132   // TODO(nick): If we changed the semantics of VideoCaptureHost so that
 133   // OnEnded() events were processed synchronously (with the RemoveClient() done
 134   // implicitly), we could avoid tracking this state here in the Controller, and
 135   // simplify the code in both places.
 136   bool session_closed;
 137 };
 138
 139 // Receives events from the VideoCaptureDevice and posts them to a
 140 // VideoCaptureController on the IO thread. An instance of this class may safely
 141 // outlive its target VideoCaptureController.
 142 //
 143 // Methods of this class may be called from any thread, and in practice will
 144 // often be called on some auxiliary thread depending on the platform and the
 145 // device type; including, for example, the DirectShow thread on Windows, the
 146 // v4l2_thread on Linux, and the UI thread for tab capture.
 147 class VideoCaptureController::VideoCaptureDeviceClient
 148     : public media::VideoCaptureDevice::Client {
 149  public:
 150   explicit VideoCaptureDeviceClient(
 151       const base::WeakPtr<VideoCaptureController>& controller,
 152       const scoped_refptr<VideoCaptureBufferPool>& buffer_pool);
 153   virtual ~VideoCaptureDeviceClient();
 154
 155   // VideoCaptureDevice::Client implementation.
 156   virtual scoped_refptr<Buffer> ReserveOutputBuffer(
 157       media::VideoFrame::Format format,
 158       const gfx::Size& size) OVERRIDE;
 159   virtual void OnIncomingCapturedData(const uint8* data,
 160                                       int length,
 161                                       const VideoCaptureFormat& frame_format,
 162                                       int rotation,
 163                                       base::TimeTicks timestamp) OVERRIDE;
 164   virtual void OnIncomingCapturedVideoFrame(
 165       const scoped_refptr<Buffer>& buffer,
 166       const VideoCaptureFormat& buffer_format,
 167       const scoped_refptr<media::VideoFrame>& frame,
 168       base::TimeTicks timestamp) OVERRIDE;
 169   virtual void OnError(const std::string& reason) OVERRIDE;
 170   virtual void OnLog(const std::string& message) OVERRIDE;
 171
 172  private:
 173   scoped_refptr<Buffer> DoReserveOutputBuffer(media::VideoFrame::Format format,
 174                                               const gfx::Size& dimensions);
 175
 176   // The controller to which we post events.
 177   const base::WeakPtr<VideoCaptureController> controller_;
 178
 179   // The pool of shared-memory buffers used for capturing.
 180   const scoped_refptr<VideoCaptureBufferPool> buffer_pool_;
 181
 182   bool first_frame_;
 183 };
 184
 185 VideoCaptureController::VideoCaptureController(int max_buffers)
 186     : buffer_pool_(new VideoCaptureBufferPool(max_buffers)),
 187       state_(VIDEO_CAPTURE_STATE_STARTED),
 188       weak_ptr_factory_(this) {
 189 }
 190
 191 VideoCaptureController::VideoCaptureDeviceClient::VideoCaptureDeviceClient(
 192     const base::WeakPtr<VideoCaptureController>& controller,
 193     const scoped_refptr<VideoCaptureBufferPool>& buffer_pool)
 194     : controller_(controller), buffer_pool_(buffer_pool), first_frame_(true) {}
 195
 196 VideoCaptureController::VideoCaptureDeviceClient::~VideoCaptureDeviceClient() {}
 197
 198 base::WeakPtr<VideoCaptureController> VideoCaptureController::GetWeakPtr() {
 199   return weak_ptr_factory_.GetWeakPtr();
 200 }
 201
 202 scoped_ptr<media::VideoCaptureDevice::Client>
 203 VideoCaptureController::NewDeviceClient() {
 204   scoped_ptr<media::VideoCaptureDevice::Client> result(
 205       new VideoCaptureDeviceClient(this->GetWeakPtr(), buffer_pool_));
 206   return result.Pass();
 207 }
 208
 209 void VideoCaptureController::AddClient(
 210     const VideoCaptureControllerID& id,
 211     VideoCaptureControllerEventHandler* event_handler,
 212     base::ProcessHandle render_process,
 213     media::VideoCaptureSessionId session_id,
 214     const media::VideoCaptureParams& params) {
 215   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 216   DVLOG(1) << "VideoCaptureController::AddClient, id " << id.device_id
 217            << ", " << params.requested_format.frame_size.ToString()
 218            << ", " << params.requested_format.frame_rate
 219            << ", " << session_id
 220            << ")";
 221
 222   // If this is the first client added to the controller, cache the parameters.
 223   if (!controller_clients_.size())
 224     video_capture_format_ = params.requested_format;
 225
 226   // Signal error in case device is already in error state.
 227   if (state_ == VIDEO_CAPTURE_STATE_ERROR) {
 228     event_handler->OnError(id);
 229     return;
 230   }
 231
 232   // Do nothing if this client has called AddClient before.
 233   if (FindClient(id, event_handler, controller_clients_))
 234     return;
 235
 236   ControllerClient* client = new ControllerClient(
 237       id, event_handler, render_process, session_id, params);
 238   // If we already have gotten frame_info from the device, repeat it to the new
 239   // client.
 240   if (state_ == VIDEO_CAPTURE_STATE_STARTED) {
 241     controller_clients_.push_back(client);
 242     return;
 243   }
 244 }
 245
 246 int VideoCaptureController::RemoveClient(
 247     const VideoCaptureControllerID& id,
 248     VideoCaptureControllerEventHandler* event_handler) {
 249   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 250   DVLOG(1) << "VideoCaptureController::RemoveClient, id " << id.device_id;
 251
 252   ControllerClient* client = FindClient(id, event_handler, controller_clients_);
 253   if (!client)
 254     return kInvalidMediaCaptureSessionId;
 255
 256   // Take back all buffers held by the |client|.
 257   for (ControllerClient::ActiveBufferMap::iterator buffer_it =
 258            client->active_buffers.begin();
 259        buffer_it != client->active_buffers.end();
 260        ++buffer_it) {
 261     buffer_pool_->RelinquishConsumerHold(buffer_it->first, 1);
 262   }
 263   client->active_buffers.clear();
 264
 265   int session_id = client->session_id;
 266   controller_clients_.remove(client);
 267   delete client;
 268
 269   return session_id;
 270 }
 271
 272 void VideoCaptureController::StopSession(int session_id) {
 273   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 274   DVLOG(1) << "VideoCaptureController::StopSession, id " << session_id;
 275
 276   ControllerClient* client = FindClient(session_id, controller_clients_);
 277
 278   if (client) {
 279     client->session_closed = true;
 280     client->event_handler->OnEnded(client->controller_id);
 281   }
 282 }
 283
 284 void VideoCaptureController::ReturnBuffer(
 285     const VideoCaptureControllerID& id,
 286     VideoCaptureControllerEventHandler* event_handler,
 287     int buffer_id,
 288     uint32 sync_point) {
 289   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 290
 291   ControllerClient* client = FindClient(id, event_handler, controller_clients_);
 292
 293   // If this buffer is not held by this client, or this client doesn't exist
 294   // in controller, do nothing.
 295   ControllerClient::ActiveBufferMap::iterator iter;
 296   if (!client || (iter = client->active_buffers.find(buffer_id)) ==
 297                      client->active_buffers.end()) {
 298     NOTREACHED();
 299     return;
 300   }
 301   scoped_refptr<media::VideoFrame> frame = iter->second;
 302   client->active_buffers.erase(iter);
 303   buffer_pool_->RelinquishConsumerHold(buffer_id, 1);
 304
 305   if (sync_point)
 306     BrowserThread::PostTask(BrowserThread::UI,
 307                             FROM_HERE,
 308                             base::Bind(&ReturnVideoFrame, frame, sync_point));
 309 }
 310
 311 const media::VideoCaptureFormat&
 312 VideoCaptureController::GetVideoCaptureFormat() const {
 313   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 314   return video_capture_format_;
 315 }
 316
 317 scoped_refptr<media::VideoCaptureDevice::Client::Buffer>
 318 VideoCaptureController::VideoCaptureDeviceClient::ReserveOutputBuffer(
 319     media::VideoFrame::Format format,
 320     const gfx::Size& size) {
 321   return DoReserveOutputBuffer(format, size);
 322 }
 323
 324 void VideoCaptureController::VideoCaptureDeviceClient::OnIncomingCapturedData(
 325     const uint8* data,
 326     int length,
 327     const VideoCaptureFormat& frame_format,
 328     int rotation,
 329     base::TimeTicks timestamp) {
 330   TRACE_EVENT0("video", "VideoCaptureController::OnIncomingCapturedData");
 331
 332   if (!frame_format.IsValid())
 333     return;
 334
 335   // Chopped pixels in width/height in case video capture device has odd
 336   // numbers for width/height.
 337   int chopped_width = 0;
 338   int chopped_height = 0;
 339   int new_unrotated_width = frame_format.frame_size.width();
 340   int new_unrotated_height = frame_format.frame_size.height();
 341
 342   if (new_unrotated_width & 1) {
 343     --new_unrotated_width;
 344     chopped_width = 1;
 345   }
 346   if (new_unrotated_height & 1) {
 347     --new_unrotated_height;
 348     chopped_height = 1;
 349   }
 350
 351   int destination_width = new_unrotated_width;
 352   int destination_height = new_unrotated_height;
 353   if (rotation == 90 || rotation == 270) {
 354     destination_width = new_unrotated_height;
 355     destination_height = new_unrotated_width;
 356   }
 357   const gfx::Size dimensions(destination_width, destination_height);
 358   if (!media::VideoFrame::IsValidConfig(media::VideoFrame::I420,
 359                                         dimensions,
 360                                         gfx::Rect(dimensions),
 361                                         dimensions)) {
 362     return;
 363   }
 364
 365   scoped_refptr<Buffer> buffer =
 366       DoReserveOutputBuffer(media::VideoFrame::I420, dimensions);
 367
 368   if (!buffer.get())
 369     return;
 370   uint8* yplane = NULL;
 371   bool flip = false;
 372   yplane = reinterpret_cast<uint8*>(buffer->data());
 373   uint8* uplane =
 374       yplane +
 375       media::VideoFrame::PlaneAllocationSize(
 376           media::VideoFrame::I420, media::VideoFrame::kYPlane, dimensions);
 377   uint8* vplane =
 378       uplane +
 379       media::VideoFrame::PlaneAllocationSize(
 380           media::VideoFrame::I420, media::VideoFrame::kUPlane, dimensions);
 381   int yplane_stride = dimensions.width();
 382   int uv_plane_stride = yplane_stride / 2;
 383   int crop_x = 0;
 384   int crop_y = 0;
 385   libyuv::FourCC origin_colorspace = libyuv::FOURCC_ANY;
 386
 387   libyuv::RotationMode rotation_mode = libyuv::kRotate0;
 388   if (rotation == 90)
 389     rotation_mode = libyuv::kRotate90;
 390   else if (rotation == 180)
 391     rotation_mode = libyuv::kRotate180;
 392   else if (rotation == 270)
 393     rotation_mode = libyuv::kRotate270;
 394
 395   switch (frame_format.pixel_format) {
 396     case media::PIXEL_FORMAT_UNKNOWN:  // Color format not set.
 397       break;
 398     case media::PIXEL_FORMAT_I420:
 399       DCHECK(!chopped_width && !chopped_height);
 400       origin_colorspace = libyuv::FOURCC_I420;
 401       break;
 402     case media::PIXEL_FORMAT_YV12:
 403       DCHECK(!chopped_width && !chopped_height);
 404       origin_colorspace = libyuv::FOURCC_YV12;
 405       break;
 406     case media::PIXEL_FORMAT_NV21:
 407       DCHECK(!chopped_width && !chopped_height);
 408       origin_colorspace = libyuv::FOURCC_NV21;
 409       break;
 410     case media::PIXEL_FORMAT_YUY2:
 411       DCHECK(!chopped_width && !chopped_height);
 412       origin_colorspace = libyuv::FOURCC_YUY2;
 413       break;
 414     case media::PIXEL_FORMAT_UYVY:
 415       DCHECK(!chopped_width && !chopped_height);
 416       origin_colorspace = libyuv::FOURCC_UYVY;
 417       break;
 418     case media::PIXEL_FORMAT_RGB24:
 419       origin_colorspace = libyuv::FOURCC_24BG;
 420 #if defined(OS_WIN)
 421       // TODO(wjia): Currently, for RGB24 on WIN, capture device always
 422       // passes in positive src_width and src_height. Remove this hardcoded
 423       // value when nagative src_height is supported. The negative src_height
 424       // indicates that vertical flipping is needed.
 425       flip = true;
 426 #endif
 427       break;
 428     case media::PIXEL_FORMAT_ARGB:
 429       origin_colorspace = libyuv::FOURCC_ARGB;
 430       break;
 431     case media::PIXEL_FORMAT_MJPEG:
 432       origin_colorspace = libyuv::FOURCC_MJPG;
 433       break;
 434     default:
 435       NOTREACHED();
 436   }
 437
 438   libyuv::ConvertToI420(data,
 439                         length,
 440                         yplane,
 441                         yplane_stride,
 442                         uplane,
 443                         uv_plane_stride,
 444                         vplane,
 445                         uv_plane_stride,
 446                         crop_x,
 447                         crop_y,
 448                         frame_format.frame_size.width(),
 449                         (flip ? -frame_format.frame_size.height() :
 450                                 frame_format.frame_size.height()),
 451                         new_unrotated_width,
 452                         new_unrotated_height,
 453                         rotation_mode,
 454                         origin_colorspace);
 455   scoped_refptr<media::VideoFrame> frame =
 456       media::VideoFrame::WrapExternalPackedMemory(
 457           media::VideoFrame::I420,
 458           dimensions,
 459           gfx::Rect(dimensions),
 460           dimensions,
 461           yplane,
 462           media::VideoFrame::AllocationSize(media::VideoFrame::I420,
 463                                             dimensions),
 464           base::SharedMemory::NULLHandle(),
 465           base::TimeDelta(),
 466           base::Closure());
 467   DCHECK(frame.get());
 468
 469   VideoCaptureFormat format(
 470       dimensions, frame_format.frame_rate, media::PIXEL_FORMAT_I420);
 471   BrowserThread::PostTask(
 472       BrowserThread::IO,
 473       FROM_HERE,
 474       base::Bind(
 475           &VideoCaptureController::DoIncomingCapturedVideoFrameOnIOThread,
 476           controller_,
 477           buffer,
 478           format,
 479           frame,
 480           timestamp));
 481
 482   if (first_frame_) {
 483     UMA_HISTOGRAM_COUNTS("Media.VideoCapture.Width",
 484                          frame_format.frame_size.width());
 485     UMA_HISTOGRAM_COUNTS("Media.VideoCapture.Height",
 486                          frame_format.frame_size.height());
 487     UMA_HISTOGRAM_ASPECT_RATIO("Media.VideoCapture.AspectRatio",
 488                                frame_format.frame_size.width(),
 489                                frame_format.frame_size.height());
 490     UMA_HISTOGRAM_COUNTS("Media.VideoCapture.FrameRate",
 491                          frame_format.frame_rate);
 492     UMA_HISTOGRAM_ENUMERATION("Media.VideoCapture.PixelFormat",
 493                               frame_format.pixel_format,
 494                               media::PIXEL_FORMAT_MAX);
 495     first_frame_ = false;
 496   }
 497 }
 498
 499 void
 500 VideoCaptureController::VideoCaptureDeviceClient::OnIncomingCapturedVideoFrame(
 501     const scoped_refptr<Buffer>& buffer,
 502     const VideoCaptureFormat& buffer_format,
 503     const scoped_refptr<media::VideoFrame>& frame,
 504     base::TimeTicks timestamp) {
 505   BrowserThread::PostTask(
 506       BrowserThread::IO,
 507       FROM_HERE,
 508       base::Bind(
 509           &VideoCaptureController::DoIncomingCapturedVideoFrameOnIOThread,
 510           controller_,
 511           buffer,
 512           buffer_format,
 513           frame,
 514           timestamp));
 515 }
 516
 517 void VideoCaptureController::VideoCaptureDeviceClient::OnError(
 518     const std::string& reason) {
 519   MediaStreamManager::SendMessageToNativeLog(
 520       "Error on video capture: " + reason);
 521   BrowserThread::PostTask(BrowserThread::IO,
 522       FROM_HERE,
 523       base::Bind(&VideoCaptureController::DoErrorOnIOThread, controller_));
 524 }
 525
 526 void VideoCaptureController::VideoCaptureDeviceClient::OnLog(
 527     const std::string& message) {
 528   MediaStreamManager::SendMessageToNativeLog("Video capture: " + message);
 529 }
 530
 531 scoped_refptr<media::VideoCaptureDevice::Client::Buffer>
 532 VideoCaptureController::VideoCaptureDeviceClient::DoReserveOutputBuffer(
 533     media::VideoFrame::Format format,
 534     const gfx::Size& dimensions) {
 535   size_t frame_bytes = 0;
 536   if (format == media::VideoFrame::NATIVE_TEXTURE) {
 537     DCHECK_EQ(dimensions.width(), 0);
 538     DCHECK_EQ(dimensions.height(), 0);
 539   } else {
 540     // The capture pipeline expects I420 for now.
 541     DCHECK_EQ(format, media::VideoFrame::I420)
 542         << "Non-I420 output buffer format " << format << " requested";
 543     frame_bytes = media::VideoFrame::AllocationSize(format, dimensions);
 544   }
 545
 546   int buffer_id_to_drop = VideoCaptureBufferPool::kInvalidId;
 547   int buffer_id =
 548       buffer_pool_->ReserveForProducer(frame_bytes, &buffer_id_to_drop);
 549   if (buffer_id == VideoCaptureBufferPool::kInvalidId)
 550     return NULL;
 551   void* data;
 552   size_t size;
 553   buffer_pool_->GetBufferInfo(buffer_id, &data, &size);
 554
 555   scoped_refptr<media::VideoCaptureDevice::Client::Buffer> output_buffer(
 556       new PoolBuffer(buffer_pool_, buffer_id, data, size));
 557
 558   if (buffer_id_to_drop != VideoCaptureBufferPool::kInvalidId) {
 559     BrowserThread::PostTask(BrowserThread::IO,
 560         FROM_HERE,
 561         base::Bind(&VideoCaptureController::DoBufferDestroyedOnIOThread,
 562                    controller_, buffer_id_to_drop));
 563   }
 564
 565   return output_buffer;
 566 }
 567
 568 VideoCaptureController::~VideoCaptureController() {
 569   STLDeleteContainerPointers(controller_clients_.begin(),
 570                              controller_clients_.end());
 571 }
 572
 573 void VideoCaptureController::DoIncomingCapturedVideoFrameOnIOThread(
 574     const scoped_refptr<media::VideoCaptureDevice::Client::Buffer>& buffer,
 575     const media::VideoCaptureFormat& buffer_format,
 576     const scoped_refptr<media::VideoFrame>& frame,
 577     base::TimeTicks timestamp) {
 578   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 579   DCHECK_NE(buffer->id(), VideoCaptureBufferPool::kInvalidId);
 580
 581   int count = 0;
 582   if (state_ == VIDEO_CAPTURE_STATE_STARTED) {
 583     for (ControllerClients::iterator client_it = controller_clients_.begin();
 584          client_it != controller_clients_.end(); ++client_it) {
 585       ControllerClient* client = *client_it;
 586       if (client->session_closed)
 587         continue;
 588
 589       if (frame->format() == media::VideoFrame::NATIVE_TEXTURE) {
 590         client->event_handler->OnMailboxBufferReady(client->controller_id,
 591                                                     buffer->id(),
 592                                                     *frame->mailbox_holder(),
 593                                                     buffer_format,
 594                                                     timestamp);
 595       } else {
 596         bool is_new_buffer = client->known_buffers.insert(buffer->id()).second;
 597         if (is_new_buffer) {
 598           // On the first use of a buffer on a client, share the memory handle.
 599           size_t memory_size = 0;
 600           base::SharedMemoryHandle remote_handle = buffer_pool_->ShareToProcess(
 601               buffer->id(), client->render_process_handle, &memory_size);
 602           client->event_handler->OnBufferCreated(
 603               client->controller_id, remote_handle, memory_size, buffer->id());
 604         }
 605
 606         client->event_handler->OnBufferReady(
 607             client->controller_id, buffer->id(), buffer_format, timestamp);
 608       }
 609
 610       bool inserted =
 611           client->active_buffers.insert(std::make_pair(buffer->id(), frame))
 612               .second;
 613       DCHECK(inserted) << "Unexpected duplicate buffer: " << buffer->id();
 614       count++;
 615     }
 616   }
 617
 618   buffer_pool_->HoldForConsumers(buffer->id(), count);
 619 }
 620
 621 void VideoCaptureController::DoErrorOnIOThread() {
 622   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 623   state_ = VIDEO_CAPTURE_STATE_ERROR;
 624
 625   for (ControllerClients::iterator client_it = controller_clients_.begin();
 626        client_it != controller_clients_.end(); ++client_it) {
 627     ControllerClient* client = *client_it;
 628     if (client->session_closed)
 629        continue;
 630
 631     client->event_handler->OnError(client->controller_id);
 632   }
 633 }
 634
 635 void VideoCaptureController::DoBufferDestroyedOnIOThread(
 636     int buffer_id_to_drop) {
 637   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 638
 639   for (ControllerClients::iterator client_it = controller_clients_.begin();
 640        client_it != controller_clients_.end(); ++client_it) {
 641     ControllerClient* client = *client_it;
 642     if (client->session_closed)
 643       continue;
 644
 645     if (client->known_buffers.erase(buffer_id_to_drop)) {
 646       client->event_handler->OnBufferDestroyed(client->controller_id,
 647                                                buffer_id_to_drop);
 648     }
 649   }
 650 }
 651
 652 VideoCaptureController::ControllerClient*
 653 VideoCaptureController::FindClient(
 654     const VideoCaptureControllerID& id,
 655     VideoCaptureControllerEventHandler* handler,
 656     const ControllerClients& clients) {
 657   for (ControllerClients::const_iterator client_it = clients.begin();
 658        client_it != clients.end(); ++client_it) {
 659     if ((*client_it)->controller_id == id &&
 660         (*client_it)->event_handler == handler) {
 661       return *client_it;
 662     }
 663   }
 664   return NULL;
 665 }
 666
 667 VideoCaptureController::ControllerClient*
 668 VideoCaptureController::FindClient(
 669     int session_id,
 670     const ControllerClients& clients) {
 671   for (ControllerClients::const_iterator client_it = clients.begin();
 672        client_it != clients.end(); ++client_it) {
 673     if ((*client_it)->session_id == session_id) {
 674       return *client_it;
 675     }
 676   }
 677   return NULL;
 678 }
 679
 680 int VideoCaptureController::GetClientCount() {
 681   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 682   return controller_clients_.size();
 683 }
 684
 685 }  // namespace content