Index: webrtc/rtc_base/bitrateallocationstrategy.cc |
diff --git a/webrtc/rtc_base/bitrateallocationstrategy.cc b/webrtc/rtc_base/bitrateallocationstrategy.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..99ecca9c3fe9dd82d83859b0ed8c46f3e200ca32 |
--- /dev/null |
+++ b/webrtc/rtc_base/bitrateallocationstrategy.cc |
@@ -0,0 +1,124 @@ |
+/* |
+ * Copyright 2017 The WebRTC Project Authors. All rights reserved. |
+ * |
+ * Use of this source code is governed by a BSD-style license |
+ * that can be found in the LICENSE file in the root of the source |
+ * tree. An additional intellectual property rights grant can be found |
+ * in the file PATENTS. All contributing project authors may |
+ * be found in the AUTHORS file in the root of the source tree. |
+ */ |
+ |
+#include "webrtc/rtc_base/bitrateallocationstrategy.h" |
+#include <algorithm> |
+#include <utility> |
+ |
+namespace rtc { |
+ |
+std::vector<uint32_t> BitrateAllocationStrategy::SetAllBitratesToMinimum( |
+ const ArrayView<const TrackConfig*> track_configs) { |
+ std::vector<uint32_t> track_allocations; |
+ for (const auto* track_config : track_configs) { |
+ track_allocations.push_back(track_config->min_bitrate_bps); |
+ } |
+ return track_allocations; |
+} |
+ |
+std::vector<uint32_t> BitrateAllocationStrategy::DistributeBitratesEvenly( |
+ const ArrayView<const TrackConfig*> track_configs, |
+ uint32_t available_bitrate) { |
+ std::vector<uint32_t> track_allocations = |
+ SetAllBitratesToMinimum(track_configs); |
+ uint32_t sum_min_bitrates = 0; |
+ uint32_t sum_max_bitrates = 0; |
+ for (const auto* track_config : track_configs) { |
+ sum_min_bitrates += track_config->min_bitrate_bps; |
+ sum_max_bitrates += track_config->max_bitrate_bps; |
+ } |
+ if (sum_min_bitrates >= available_bitrate) { |
+ return track_allocations; |
+ } else if (available_bitrate >= sum_max_bitrates) { |
+ auto track_allocations_it = track_allocations.begin(); |
+ for (const auto* track_config : track_configs) { |
+ *track_allocations_it++ = track_config->max_bitrate_bps; |
+ } |
+ return track_allocations; |
+ } else { |
+ // If sum_min_bitrates < available_bitrate < sum_max_bitrates allocate |
+ // bitrates evenly up to max_bitrate_bps starting from the track with the |
+ // lowest max_bitrate_bps. Reminder of available bitrate split evenly among |
+ // remaining tracks. |
+ std::multimap<uint32_t, size_t> max_bitrate_sorted_configs; |
+ for (const TrackConfig** track_configs_it = track_configs.begin(); |
+ track_configs_it != track_configs.end(); track_configs_it++) { |
+ max_bitrate_sorted_configs.insert(std::pair<uint32_t, size_t>( |
+ (*track_configs_it)->max_bitrate_bps, |
+ track_configs_it - track_configs.begin())); |
+ } |
+ uint32_t total_available_increase = (available_bitrate - sum_min_bitrates); |
+ int processed_configs = 0; |
+ for (const auto& track_config_pair : max_bitrate_sorted_configs) { |
+ uint32_t available_increase = |
+ total_available_increase / |
+ (static_cast<uint32_t>(track_configs.size() - processed_configs)); |
+ uint32_t consumed_increase = |
+ std::min(track_configs[track_config_pair.second]->max_bitrate_bps - |
+ track_configs[track_config_pair.second]->min_bitrate_bps, |
+ available_increase); |
+ track_allocations[track_config_pair.second] += consumed_increase; |
+ total_available_increase -= consumed_increase; |
+ ++processed_configs; |
+ } |
+ return track_allocations; |
+ } |
+} |
+ |
+AudioPriorityBitrateAllocationStrategy::AudioPriorityBitrateAllocationStrategy( |
+ std::string audio_track_id, |
+ uint32_t sufficient_audio_bitrate) |
+ : audio_track_id_(audio_track_id), |
+ sufficient_audio_bitrate_(sufficient_audio_bitrate) {} |
+ |
+std::vector<uint32_t> AudioPriorityBitrateAllocationStrategy::AllocateBitrates( |
+ uint32_t available_bitrate, |
+ const ArrayView<const TrackConfig*> track_configs) { |
+ const TrackConfig* audio_track_config = NULL; |
+ size_t audio_config_index = -1; |
+ uint32_t sum_min_bitrates = 0; |
+ |
+ for (auto*& track_config : track_configs) { |
+ sum_min_bitrates += track_config->min_bitrate_bps; |
+ if (track_config->track_id == audio_track_id_) { |
+ audio_track_config = track_config; |
+ audio_config_index = &track_config - &track_configs[0]; |
+ } |
+ } |
+ if (audio_track_config == NULL) { |
+ return DistributeBitratesEvenly(track_configs, available_bitrate); |
+ } |
+ auto safe_sufficient_audio_bitrate = std::min( |
+ std::max(audio_track_config->min_bitrate_bps, sufficient_audio_bitrate_), |
+ audio_track_config->max_bitrate_bps); |
+ if (available_bitrate <= sum_min_bitrates) { |
+ return SetAllBitratesToMinimum(track_configs); |
+ } else { |
+ if (available_bitrate <= sum_min_bitrates + safe_sufficient_audio_bitrate - |
+ audio_track_config->min_bitrate_bps) { |
+ std::vector<uint32_t> track_allocations = |
+ SetAllBitratesToMinimum(track_configs); |
+ track_allocations[audio_config_index] += |
+ available_bitrate - sum_min_bitrates; |
+ return track_allocations; |
+ } else { |
+ const TrackConfig* saved_track_config = track_configs[audio_config_index]; |
+ TrackConfig sufficient_track_config(*track_configs[audio_config_index]); |
+ sufficient_track_config.min_bitrate_bps = safe_sufficient_audio_bitrate; |
+ track_configs[audio_config_index] = &sufficient_track_config; |
+ std::vector<uint32_t> track_allocations = |
+ DistributeBitratesEvenly(track_configs, available_bitrate); |
+ track_configs[audio_config_index] = saved_track_config; |
+ return track_allocations; |
+ } |
+ } |
+} |
+ |
+} // namespace rtc |