Implement all resolution change policies for desktop and tab capture.

content/browser/media/capture/content_video_capture_device_core.cc

Index: content/browser/media/capture/content_video_capture_device_core.cc
diff --git a/content/browser/media/capture/content_video_capture_device_core.cc b/content/browser/media/capture/content_video_capture_device_core.cc
index 8d44104c1c418f4a3f21d9648b682d4a34ce74d7..8a06da43884697362f1d7c3fb475736cf4be2818 100644
--- a/content/browser/media/capture/content_video_capture_device_core.cc
+++ b/content/browser/media/capture/content_video_capture_device_core.cc
@@ -49,7 +49,9 @@ ThreadSafeCaptureOracle::ThreadSafeCaptureOracle(
       oracle_(base::TimeDelta::FromMicroseconds(
           static_cast<int64>(1000000.0 / params.requested_format.frame_rate +
                              0.5 /* to round to nearest int */))),
-      params_(params) {}
+      params_(params),
+      resolution_evaluator_(params.requested_format.frame_size,
+                            params.resolution_change_policy) {}
 
 ThreadSafeCaptureOracle::~ThreadSafeCaptureOracle() {}
 
@@ -67,9 +69,7 @@ bool ThreadSafeCaptureOracle::ObserveEventAndDecideCapture(
   if (!client_)
     return false;  // Capture is stopped.
 
-  if (capture_size_.IsEmpty())
-    capture_size_ = max_frame_size();
-  const gfx::Size visible_size = capture_size_;
+  const gfx::Size visible_size = resolution_evaluator_.capture_size();
   // Always round up the coded size to multiple of 16 pixels.
   // See http://crbug.com/402151.
   const gfx::Size coded_size((visible_size.width() + 15) & ~15,
@@ -141,30 +141,15 @@ bool ThreadSafeCaptureOracle::ObserveEventAndDecideCapture(
 
 gfx::Size ThreadSafeCaptureOracle::GetCaptureSize() const {
   base::AutoLock guard(lock_);
-  return capture_size_.IsEmpty() ? max_frame_size() : capture_size_;
+  return resolution_evaluator_.capture_size();
 }
 
 void ThreadSafeCaptureOracle::UpdateCaptureSize(const gfx::Size& source_size) {
   base::AutoLock guard(lock_);
-
-  // Update |capture_size_| based on |source_size| if either: 1) The resolution
-  // change policy specifies fixed frame sizes and |capture_size_| has not yet
-  // been set; or 2) The resolution change policy specifies dynamic frame
-  // sizes.
-  if (capture_size_.IsEmpty() || params_.resolution_change_policy ==
-      media::RESOLUTION_POLICY_ANY_WITHIN_LIMIT) {
-    capture_size_ = source_size;
-    // The capture size should not exceed the maximum frame size.
-    if (capture_size_.width() > max_frame_size().width() ||
-        capture_size_.height() > max_frame_size().height()) {
-      capture_size_ = media::ComputeLetterboxRegion(
-          gfx::Rect(max_frame_size()), capture_size_).size();
-    }
-    // The capture size must be even and not less than the minimum frame size.
-    capture_size_ = gfx::Size(
-        std::max(kMinFrameWidth, MakeEven(capture_size_.width())),
-        std::max(kMinFrameHeight, MakeEven(capture_size_.height())));
-  }
+  resolution_evaluator_.UpdateForNewSourceSize(source_size);
+  VLOG(1) << "Source size changed to " << source_size.ToString()
+          << " --> Capture size is now "
+          << resolution_evaluator_.capture_size().ToString();
 }
 
 void ThreadSafeCaptureOracle::Stop() {
@@ -234,23 +219,15 @@ void ContentVideoCaptureDeviceCore::AllocateAndStart(
     return;
   }
 
-   if (params.requested_format.frame_size.width() < kMinFrameWidth ||
-       params.requested_format.frame_size.height() < kMinFrameHeight) {
-     std::string error_msg =
-         "invalid frame size: " + params.requested_format.frame_size.ToString();
-     DVLOG(1) << error_msg;
-     client->OnError(error_msg);
-     return;
-   }
-
-  media::VideoCaptureParams new_params = params;
-  // Frame dimensions must each be an even integer since the client wants (or
-  // will convert to) YUV420.

[Wez, 2015/05/14 01:44:54]

Do we need to worry about the I420 even-size limitations here?

[miu, 2015/05/14 21:12:26]

No.  As part of this change I realized we were writing a lot of redundant "make
even" code all over the place.  I've eliminated it in most places throughout
these files.  There are only two code points that still do it (the ones where an
ARGB frame is converted to an I420 frame).  I ran a ton of manual tests to
double-check everything end-to-end is working correctly.

-  new_params.requested_format.frame_size.SetSize(
-      MakeEven(params.requested_format.frame_size.width()),
-      MakeEven(params.requested_format.frame_size.height()));
+  if (params.requested_format.frame_size.IsEmpty()) {
+    std::string error_msg =
+        "invalid frame size: " + params.requested_format.frame_size.ToString();
+    DVLOG(1) << error_msg;
+    client->OnError(error_msg);
+    return;
+  }
 
-  oracle_proxy_ = new ThreadSafeCaptureOracle(client.Pass(), new_params);
+  oracle_proxy_ = new ThreadSafeCaptureOracle(client.Pass(), params);
 
   // Starts the capture machine asynchronously.
   BrowserThread::PostTaskAndReplyWithResult(
@@ -259,7 +236,7 @@ void ContentVideoCaptureDeviceCore::AllocateAndStart(
       base::Bind(&VideoCaptureMachine::Start,
                  base::Unretained(capture_machine_.get()),
                  oracle_proxy_,
-                 new_params),
+                 params),
       base::Bind(&ContentVideoCaptureDeviceCore::CaptureStarted, AsWeakPtr()));
 
   TransitionStateTo(kCapturing);