Index: media/base/download_rate_monitor.cc |
=================================================================== |
--- media/base/download_rate_monitor.cc (revision 118589) |
+++ media/base/download_rate_monitor.cc (working copy) |
@@ -1,4 +1,4 @@ |
-// Copyright (c) 2012 The Chromium Authors. All rights reserved. |
+// 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. |
@@ -91,6 +91,8 @@ |
if (stopped_) |
return; |
+ is_downloading_data_ = true; |
+ |
// Check monotonically nondecreasing constraint. |
base::Time previous_time; |
if (!current_sample_.is_null()) |
@@ -118,11 +120,12 @@ |
} |
void DownloadRateMonitor::SetNetworkActivity(bool is_downloading_data) { |
- // Record when download defers for the first time. |
- if (!is_downloading_data && !has_deferred_) { |
- has_deferred_ = true; |
- NotifyCanPlayThroughIfNeeded(); |
- } |
+ if (is_downloading_data == is_downloading_data_) |
+ return; |
+ // Invalidate the current sample if downloading is going from start to stopped |
+ // or vice versa. |
+ current_sample_.Reset(); |
+ is_downloading_data_ = is_downloading_data; |
} |
void DownloadRateMonitor::Stop() { |
@@ -136,13 +139,13 @@ |
has_notified_can_play_through_ = false; |
current_sample_.Reset(); |
sample_window_.clear(); |
+ is_downloading_data_ = false; |
total_bytes_ = -1; |
buffered_bytes_ = 0; |
local_source_ = false; |
bitrate_ = 0; |
stopped_ = true; |
streaming_ = false; |
- has_deferred_ = false; |
} |
DownloadRateMonitor::~DownloadRateMonitor() { } |
@@ -207,9 +210,8 @@ |
if (local_source_ || streaming_) |
return true; |
- // If all bytes are buffered or if enough bytes were buffered such that |
- // downloading has deferred, fire CanPlayThrough. |
- if (buffered_bytes_ == total_bytes_ || has_deferred_) |
+ // If all bytes are buffered, fire CanPlayThrough. |
+ if (buffered_bytes_ == total_bytes_) |
return true; |
// If bitrate is unknown, optimistically fire CanPlayThrough immediately. |
@@ -226,9 +228,12 @@ |
if (download_rate > 0) |
return download_rate >= bytes_needed_per_second; |
- // With very fast connections, we may want to fire CanPlayThrough before |
- // waiting for the sample window size to reach |kNumberOfSamples|. Check for |
- // this scenario. |
+ // If download rate is unknown, it may be because the media is being |
+ // downloaded so fast that it cannot collect an adequate number of samples |
+ // before the download gets deferred. |
+ // |
+ // To catch this case, we also look at how much data is being downloaded |
+ // immediately after the download begins. |
if (sample_window_.size() < kNumberOfSamples) { |
int64 bytes_downloaded_since_start = |
bytes_downloaded_in_window() + current_sample_.bytes_downloaded(); |