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/*
* Copyright (c) 2012 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.
*/
#ifndef MODULES_AUDIO_CODING_NETEQ_PACKET_BUFFER_H_
#define MODULES_AUDIO_CODING_NETEQ_PACKET_BUFFER_H_
#include "absl/types/optional.h"
#include "modules/audio_coding/neteq/decoder_database.h"
#include "modules/audio_coding/neteq/packet.h"
#include "modules/include/module_common_types_public.h" // IsNewerTimestamp
namespace webrtc {
class DecoderDatabase;
class StatisticsCalculator;
class TickTimer;
struct SmartFlushingConfig {
// When calculating the flushing threshold, the maximum between the target
// level and this value is used.
int target_level_threshold_ms = 500;
// A smart flush is triggered when the packet buffer contains a multiple of
// the target level.
int target_level_multiplier = 3;
};
// This is the actual buffer holding the packets before decoding.
class PacketBuffer {
public:
enum BufferReturnCodes {
kOK = 0,
kFlushed,
kPartialFlush,
kNotFound,
kBufferEmpty,
kInvalidPacket,
kInvalidPointer
};
// Constructor creates a buffer which can hold a maximum of
// `max_number_of_packets` packets.
PacketBuffer(size_t max_number_of_packets, const TickTimer* tick_timer);
// Deletes all packets in the buffer before destroying the buffer.
virtual ~PacketBuffer();
PacketBuffer(const PacketBuffer&) = delete;
PacketBuffer& operator=(const PacketBuffer&) = delete;
// Flushes the buffer and deletes all packets in it.
virtual void Flush(StatisticsCalculator* stats);
// Partial flush. Flush packets but leave some packets behind.
virtual void PartialFlush(int target_level_ms,
size_t sample_rate,
size_t last_decoded_length,
StatisticsCalculator* stats);
// Returns true for an empty buffer.
virtual bool Empty() const;
// Inserts `packet` into the buffer. The buffer will take over ownership of
// the packet object.
// Returns PacketBuffer::kOK on success, PacketBuffer::kFlushed if the buffer
// was flushed due to overfilling.
virtual int InsertPacket(Packet&& packet,
StatisticsCalculator* stats,
size_t last_decoded_length,
size_t sample_rate,
int target_level_ms,
const DecoderDatabase& decoder_database);
// Inserts a list of packets into the buffer. The buffer will take over
// ownership of the packet objects.
// Returns PacketBuffer::kOK if all packets were inserted successfully.
// If the buffer was flushed due to overfilling, only a subset of the list is
// inserted, and PacketBuffer::kFlushed is returned.
// The last three parameters are included for legacy compatibility.
// TODO(hlundin): Redesign to not use current_*_payload_type and
// decoder_database.
virtual int InsertPacketList(
PacketList* packet_list,
const DecoderDatabase& decoder_database,
absl::optional<uint8_t>* current_rtp_payload_type,
absl::optional<uint8_t>* current_cng_rtp_payload_type,
StatisticsCalculator* stats,
size_t last_decoded_length,
size_t sample_rate,
int target_level_ms);
// Gets the timestamp for the first packet in the buffer and writes it to the
// output variable `next_timestamp`.
// Returns PacketBuffer::kBufferEmpty if the buffer is empty,
// PacketBuffer::kOK otherwise.
virtual int NextTimestamp(uint32_t* next_timestamp) const;
// Gets the timestamp for the first packet in the buffer with a timestamp no
// lower than the input limit `timestamp`. The result is written to the output
// variable `next_timestamp`.
// Returns PacketBuffer::kBufferEmpty if the buffer is empty,
// PacketBuffer::kOK otherwise.
virtual int NextHigherTimestamp(uint32_t timestamp,
uint32_t* next_timestamp) const;
// Returns a (constant) pointer to the first packet in the buffer. Returns
// NULL if the buffer is empty.
virtual const Packet* PeekNextPacket() const;
// Extracts the first packet in the buffer and returns it.
// Returns an empty optional if the buffer is empty.
virtual absl::optional<Packet> GetNextPacket();
// Discards the first packet in the buffer. The packet is deleted.
// Returns PacketBuffer::kBufferEmpty if the buffer is empty,
// PacketBuffer::kOK otherwise.
virtual int DiscardNextPacket(StatisticsCalculator* stats);
// Discards all packets that are (strictly) older than timestamp_limit,
// but newer than timestamp_limit - horizon_samples. Setting horizon_samples
// to zero implies that the horizon is set to half the timestamp range. That
// is, if a packet is more than 2^31 timestamps into the future compared with
// timestamp_limit (including wrap-around), it is considered old.
virtual void DiscardOldPackets(uint32_t timestamp_limit,
uint32_t horizon_samples,
StatisticsCalculator* stats);
// Discards all packets that are (strictly) older than timestamp_limit.
virtual void DiscardAllOldPackets(uint32_t timestamp_limit,
StatisticsCalculator* stats);
// Removes all packets with a specific payload type from the buffer.
virtual void DiscardPacketsWithPayloadType(uint8_t payload_type,
StatisticsCalculator* stats);
// Returns the number of packets in the buffer, including duplicates and
// redundant packets.
virtual size_t NumPacketsInBuffer() const;
// Returns the number of samples in the buffer, including samples carried in
// duplicate and redundant packets.
virtual size_t NumSamplesInBuffer(size_t last_decoded_length) const;
// Returns the total duration in samples that the packets in the buffer spans
// across.
virtual size_t GetSpanSamples(size_t last_decoded_length,
size_t sample_rate,
bool count_waiting_time) const;
// Returns true if the packet buffer contains any DTX or CNG packets.
virtual bool ContainsDtxOrCngPacket(
const DecoderDatabase* decoder_database) const;
// Static method returning true if `timestamp` is older than `timestamp_limit`
// but less than `horizon_samples` behind `timestamp_limit`. For instance,
// with timestamp_limit = 100 and horizon_samples = 10, a timestamp in the
// range (90, 100) is considered obsolete, and will yield true.
// Setting `horizon_samples` to 0 is the same as setting it to 2^31, i.e.,
// half the 32-bit timestamp range.
static bool IsObsoleteTimestamp(uint32_t timestamp,
uint32_t timestamp_limit,
uint32_t horizon_samples) {
return IsNewerTimestamp(timestamp_limit, timestamp) &&
(horizon_samples == 0 ||
IsNewerTimestamp(timestamp, timestamp_limit - horizon_samples));
}
private:
absl::optional<SmartFlushingConfig> smart_flushing_config_;
size_t max_number_of_packets_;
PacketList buffer_;
const TickTimer* tick_timer_;
};
} // namespace webrtc
#endif // MODULES_AUDIO_CODING_NETEQ_PACKET_BUFFER_H_
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