add components for integration test which will detect breakage of media pipeline with video captu...

media/video/capture/fake_capture_video_decoder.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 "media/video/capture/fake_capture_video_decoder.h"
+
+#include "base/bind.h"
+#include "base/message_loop.h"
+#include "media/base/demuxer_stream.h"
+#include "media/base/filter_host.h"
+#include "media/base/limits.h"
+#include "media/base/video_util.h"
+
+namespace media {
+
+FakeCaptureVideoDecoder::FakeCaptureVideoDecoder(
+    base::MessageLoopProxy* message_loop_proxy,
+    const VideoCapture::VideoCaptureCapability& capability)

[scherkus (not reviewing), 2011/12/21 20:26:45]

if you passed in a gfx::Rect and base::TimeDelta for duration you wouldn't need
to depend on VideoCapture code at all -- in fact you could move this class to
media/filters/ and name it something like "VideoFrameGenerator"

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+    : message_loop_proxy_(message_loop_proxy),
+      capability_(capability),

[scherkus (not reviewing), 2011/12/21 20:26:45]

this isn't used -- remove?

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+      natural_size_(capability.width, capability.height),
+      state_(kUnInitialized) {
+  int64 interval = 33;
+  if (capability.max_fps > 0) {
+    interval = (1000 + capability.max_fps - 1) / capability.max_fps;
+  }
+  frame_interval_ms_ = base::TimeDelta::FromMilliseconds(interval);

[scherkus (not reviewing), 2011/12/21 20:26:45]

nit: why not name this duration?

also ms suffix isn't needed since it's a TimeDelta

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+}
+
+FakeCaptureVideoDecoder::~FakeCaptureVideoDecoder() {}
+
+void FakeCaptureVideoDecoder::Initialize(
+    DemuxerStream* demuxer_stream,
+    const PipelineStatusCB& filter_callback,
+    const StatisticsCallback& stat_callback) {
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(&FakeCaptureVideoDecoder::InitializeOnDecoderThread,
+                 this, make_scoped_refptr(demuxer_stream),
+                 filter_callback, stat_callback));
+}
+
+void FakeCaptureVideoDecoder::Read(const ReadCB& callback) {
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(&FakeCaptureVideoDecoder::ReadOnDecoderThread,
+                 this, callback));
+}
+
+const gfx::Size& FakeCaptureVideoDecoder::natural_size() {
+  return natural_size_;
+}
+
+void FakeCaptureVideoDecoder::Pause(const base::Closure& callback) {
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(&FakeCaptureVideoDecoder::PauseOnDecoderThread,
+                 this, callback));
+}
+
+void FakeCaptureVideoDecoder::Flush(const base::Closure& callback) {
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(&FakeCaptureVideoDecoder::FlushOnDecoderThread,
+                 this, callback));
+}
+
+void FakeCaptureVideoDecoder::Stop(const base::Closure& callback) {
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(&FakeCaptureVideoDecoder::StopOnDecoderThread,
+                 this, callback));
+}
+
+void FakeCaptureVideoDecoder::Seek(base::TimeDelta time,
+                                   const FilterStatusCB& cb) {
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(&FakeCaptureVideoDecoder::SeekOnDecoderThread,
+                 this, time, cb));
+}
+
+void FakeCaptureVideoDecoder::InitializeOnDecoderThread(
+    DemuxerStream* demuxer_stream,
+    const PipelineStatusCB& filter_callback,
+    const StatisticsCallback& stat_callback) {
+  DVLOG(1) << "InitializeOnDecoderThread";
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+
+  statistics_callback_ = stat_callback;

[scherkus (not reviewing), 2011/12/21 20:26:45]

if you're not using this you don't have to save it

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+  filter_callback.Run(PIPELINE_OK);
+  state_ = kNormal;
+}
+
+void FakeCaptureVideoDecoder::ReadOnDecoderThread(const ReadCB& callback) {
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+  CHECK(read_cb_.is_null());
+  read_cb_ = callback;
+  GenerateFrameOnDecoderThread();

[scherkus (not reviewing), 2011/12/21 20:26:45]

don't even bother saving the callback -- just generate the frame here
immediately run unless stopped

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+}
+
+void FakeCaptureVideoDecoder::PauseOnDecoderThread(

[scherkus (not reviewing), 2011/12/21 20:26:45]

you shouldn't have to do anything on Pause() -- delete the code and let the
default impl take care of running the callback

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+    const base::Closure& callback) {
+  DVLOG(1) << "PauseOnDecoderThread";
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+  state_ = kPaused;
+  VideoDecoder::Pause(callback);
+}
+
+void FakeCaptureVideoDecoder::FlushOnDecoderThread(

[scherkus (not reviewing), 2011/12/21 20:26:45]

you shouldn't have to do anything on Flush() -- delete the code and let the
default impl take care of running the callback

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+    const base::Closure& callback) {
+  DVLOG(1) << "FlushOnDecoderThread";
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+  if (!read_cb_.is_null()) {
+    scoped_refptr<VideoFrame> video_frame =
+        VideoFrame::CreateBlackFrame(natural_size_.width(),
+                                     natural_size_.height());
+    DeliverFrame(video_frame);
+  }
+  VideoDecoder::Flush(callback);
+}
+
+void FakeCaptureVideoDecoder::StopOnDecoderThread(
+    const base::Closure& callback) {
+  DVLOG(1) << "StopOnDecoderThread";
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+  state_ = kStopped;
+  VideoDecoder::Stop(callback);

[scherkus (not reviewing), 2011/12/21 20:26:45]

just run the callback yourself :)

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+}
+
+void FakeCaptureVideoDecoder::SeekOnDecoderThread(

[scherkus (not reviewing), 2011/12/21 20:26:45]

you shouldn't have to do anything on Seek() -- delete the code and let the
default impl take care of running the callback

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+    base::TimeDelta time, const FilterStatusCB& cb) {
+  DVLOG(1) << "SeekOnDecoderThread";
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+
+  cb.Run(PIPELINE_OK);
+  state_ = kNormal;
+  host()->SetNaturalVideoSize(natural_size_);

[scherkus (not reviewing), 2011/12/21 20:26:45]

this shouldn't be needed as VideoRendererBase calls this method

[wjia(left Chromium), 2012/01/03 17:08:12]

Done.

+  GenerateFrameOnDecoderThread();
+}
+
+void FakeCaptureVideoDecoder::GenerateFrameOnDecoderThread() {
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+
+  if (read_cb_.is_null() || kNormal != state_)
+    return;
+
+  // Always allocate a new frame.
+  //
+  // TODO(scherkus): migrate this to proper buffer recycling.
+  scoped_refptr<VideoFrame> video_frame =
+      VideoFrame::CreateFrame(VideoFrame::YV12,
+                              natural_size_.width(),
+                              natural_size_.height(),
+                              base::TimeDelta(),

[scherkus (not reviewing), 2011/12/21 20:26:45]

every timestamp is zero?

[wjia(left Chromium), 2012/01/03 17:08:12]

I thought frame_duration is good enough. current_time has been added.

+                              frame_interval_ms_);
+
+  // TODO(wjia): set pixel data to pre-defined patterns if it's desired to
+  // verify frame content.
+  DeliverFrame(video_frame);
+}
+
+void FakeCaptureVideoDecoder::DeliverFrame(
+    const scoped_refptr<VideoFrame>& video_frame) {
+  // Reset the callback before running to protect against reentrancy.
+  ReadCB read_cb = read_cb_;
+  read_cb_.Reset();
+  read_cb.Run(video_frame);
+}
+
+}  // namespace media