media/blink/buffered_data_source_host_impl.cc

   1 // Copyright 2014 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 "media/blink/buffered_data_source_host_impl.h"
   6
   7 #include "media/base/timestamp_constants.h"
   8
   9 namespace media {
  10
  11 BufferedDataSourceHostImpl::BufferedDataSourceHostImpl()
  12     : total_bytes_(0),
  13       did_loading_progress_(false) { }
  14
  15 BufferedDataSourceHostImpl::~BufferedDataSourceHostImpl() { }
  16
  17 void BufferedDataSourceHostImpl::SetTotalBytes(int64 total_bytes) {
  18   total_bytes_ = total_bytes;
  19 }
  20
  21 void BufferedDataSourceHostImpl::AddBufferedByteRange(int64 start, int64 end) {
  22   buffered_byte_ranges_.Add(start, end);
  23   did_loading_progress_ = true;
  24 }
  25
  26 static base::TimeDelta TimeForByteOffset(
  27     int64 byte_offset, int64 total_bytes, base::TimeDelta duration) {
  28   double position = static_cast<double>(byte_offset) / total_bytes;
  29   // Snap to the beginning/end where the approximation can look especially bad.
  30   if (position < 0.01)
  31     return base::TimeDelta();
  32   if (position > 0.99)
  33     return duration;
  34   return base::TimeDelta::FromMilliseconds(
  35       static_cast<int64>(position * duration.InMilliseconds()));
  36 }
  37
  38 void BufferedDataSourceHostImpl::AddBufferedTimeRanges(
  39     Ranges<base::TimeDelta>* buffered_time_ranges,
  40     base::TimeDelta media_duration) const {
  41   DCHECK(media_duration != kNoTimestamp());
  42   DCHECK(media_duration != kInfiniteDuration());
  43   if (total_bytes_ && buffered_byte_ranges_.size()) {
  44     for (size_t i = 0; i < buffered_byte_ranges_.size(); ++i) {
  45       int64 start = buffered_byte_ranges_.start(i);
  46       int64 end = buffered_byte_ranges_.end(i);
  47       buffered_time_ranges->Add(
  48           TimeForByteOffset(start, total_bytes_, media_duration),
  49           TimeForByteOffset(end, total_bytes_, media_duration));
  50     }
  51   }
  52 }
  53
  54 bool BufferedDataSourceHostImpl::DidLoadingProgress() {
  55   bool ret = did_loading_progress_;
  56   did_loading_progress_ = false;
  57   return ret;
  58 }
  59
  60 }  // namespace media