blob: a88898fc0300f1a837abcb2dd7d1e4a1b7e3facd [file] [log] [blame]
* Copyright (c) 2014 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 <queue>
#include "webrtc/modules/include/module_common_types.h"
#include "webrtc/rtc_base/basictypes.h"
#include "webrtc/typedefs.h"
namespace webrtc {
class RtcEventLog;
// Note that this class isn't thread-safe by itself and therefore relies
// on being protected by the caller.
class BitrateProber {
explicit BitrateProber(RtcEventLog* event_log);
void SetEnabled(bool enable);
// Returns true if the prober is in a probing session, i.e., it currently
// wants packets to be sent out according to the time returned by
// TimeUntilNextProbe().
bool IsProbing() const;
// Initializes a new probing session if the prober is allowed to probe. Does
// not initialize the prober unless the packet size is large enough to probe
// with.
void OnIncomingPacket(size_t packet_size);
// Create a cluster used to probe for |bitrate_bps| with |num_probes| number
// of probes.
void CreateProbeCluster(int bitrate_bps, int64_t now_ms);
// Returns the number of milliseconds until the next probe should be sent to
// get accurate probing.
int TimeUntilNextProbe(int64_t now_ms);
// Information about the current probing cluster.
PacedPacketInfo CurrentCluster() const;
// Returns the minimum number of bytes that the prober recommends for
// the next probe.
size_t RecommendedMinProbeSize() const;
// Called to report to the prober that a probe has been sent. In case of
// multiple packets per probe, this call would be made at the end of sending
// the last packet in probe. |probe_size| is the total size of all packets
// in probe.
void ProbeSent(int64_t now_ms, size_t probe_size);
enum class ProbingState {
// Probing will not be triggered in this state at all times.
// Probing is enabled and ready to trigger on the first packet arrival.
// Probe cluster is filled with the set of data rates to be probed and
// probes are being sent.
// Probing is enabled, but currently suspended until an explicit trigger
// to start probing again.
// A probe cluster consists of a set of probes. Each probe in turn can be
// divided into a number of packets to accommodate the MTU on the network.
struct ProbeCluster {
PacedPacketInfo pace_info;
int sent_probes = 0;
int sent_bytes = 0;
int64_t time_created_ms = -1;
int64_t time_started_ms = -1;
int retries = 0;
// Resets the state of the prober and clears any cluster/timing data tracked.
void ResetState(int64_t now_ms);
int64_t GetNextProbeTime(const ProbeCluster& cluster);
ProbingState probing_state_;
// Probe bitrate per packet. These are used to compute the delta relative to
// the previous probe packet based on the size and time when that packet was
// sent.
std::queue<ProbeCluster> clusters_;
// Time the next probe should be sent when in kActive state.
int64_t next_probe_time_ms_;
int next_cluster_id_;
RtcEventLog* const event_log_;
} // namespace webrtc