1 /* 2 * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_BUFFER_H_ 12 #define WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_BUFFER_H_ 13 14 #include "webrtc/base/constructormagic.h" 15 #include "webrtc/modules/audio_coding/neteq/packet.h" 16 #include "webrtc/typedefs.h" 17 18 namespace webrtc { 19 20 // Forward declaration. 21 class DecoderDatabase; 22 23 // This is the actual buffer holding the packets before decoding. 24 class PacketBuffer { 25 public: 26 enum BufferReturnCodes { 27 kOK = 0, 28 kFlushed, 29 kNotFound, 30 kBufferEmpty, 31 kInvalidPacket, 32 kInvalidPointer 33 }; 34 35 // Constructor creates a buffer which can hold a maximum of 36 // |max_number_of_packets| packets. 37 PacketBuffer(size_t max_number_of_packets); 38 39 // Deletes all packets in the buffer before destroying the buffer. 40 virtual ~PacketBuffer(); 41 42 // Flushes the buffer and deletes all packets in it. 43 virtual void Flush(); 44 45 // Returns true for an empty buffer. 46 virtual bool Empty() const; 47 48 // Inserts |packet| into the buffer. The buffer will take over ownership of 49 // the packet object. 50 // Returns PacketBuffer::kOK on success, PacketBuffer::kFlushed if the buffer 51 // was flushed due to overfilling. 52 virtual int InsertPacket(Packet* packet); 53 54 // Inserts a list of packets into the buffer. The buffer will take over 55 // ownership of the packet objects. 56 // Returns PacketBuffer::kOK if all packets were inserted successfully. 57 // If the buffer was flushed due to overfilling, only a subset of the list is 58 // inserted, and PacketBuffer::kFlushed is returned. 59 // The last three parameters are included for legacy compatibility. 60 // TODO(hlundin): Redesign to not use current_*_payload_type and 61 // decoder_database. 62 virtual int InsertPacketList(PacketList* packet_list, 63 const DecoderDatabase& decoder_database, 64 uint8_t* current_rtp_payload_type, 65 uint8_t* current_cng_rtp_payload_type); 66 67 // Gets the timestamp for the first packet in the buffer and writes it to the 68 // output variable |next_timestamp|. 69 // Returns PacketBuffer::kBufferEmpty if the buffer is empty, 70 // PacketBuffer::kOK otherwise. 71 virtual int NextTimestamp(uint32_t* next_timestamp) const; 72 73 // Gets the timestamp for the first packet in the buffer with a timestamp no 74 // lower than the input limit |timestamp|. The result is written to the output 75 // variable |next_timestamp|. 76 // Returns PacketBuffer::kBufferEmpty if the buffer is empty, 77 // PacketBuffer::kOK otherwise. 78 virtual int NextHigherTimestamp(uint32_t timestamp, 79 uint32_t* next_timestamp) const; 80 81 // Returns a (constant) pointer the RTP header of the first packet in the 82 // buffer. Returns NULL if the buffer is empty. 83 virtual const RTPHeader* NextRtpHeader() const; 84 85 // Extracts the first packet in the buffer and returns a pointer to it. 86 // Returns NULL if the buffer is empty. The caller is responsible for deleting 87 // the packet. 88 // Subsequent packets with the same timestamp as the one extracted will be 89 // discarded and properly deleted. The number of discarded packets will be 90 // written to the output variable |discard_count|. 91 virtual Packet* GetNextPacket(size_t* discard_count); 92 93 // Discards the first packet in the buffer. The packet is deleted. 94 // Returns PacketBuffer::kBufferEmpty if the buffer is empty, 95 // PacketBuffer::kOK otherwise. 96 virtual int DiscardNextPacket(); 97 98 // Discards all packets that are (strictly) older than timestamp_limit, 99 // but newer than timestamp_limit - horizon_samples. Setting horizon_samples 100 // to zero implies that the horizon is set to half the timestamp range. That 101 // is, if a packet is more than 2^31 timestamps into the future compared with 102 // timestamp_limit (including wrap-around), it is considered old. 103 // Returns number of packets discarded. 104 virtual int DiscardOldPackets(uint32_t timestamp_limit, 105 uint32_t horizon_samples); 106 107 // Discards all packets that are (strictly) older than timestamp_limit. 108 virtual int DiscardAllOldPackets(uint32_t timestamp_limit); 109 110 // Returns the number of packets in the buffer, including duplicates and 111 // redundant packets. 112 virtual size_t NumPacketsInBuffer() const; 113 114 // Returns the number of samples in the buffer, including samples carried in 115 // duplicate and redundant packets. 116 virtual size_t NumSamplesInBuffer(DecoderDatabase* decoder_database, 117 size_t last_decoded_length) const; 118 119 // Increase the waiting time counter for every packet in the buffer by |inc|. 120 // The default value for |inc| is 1. 121 virtual void IncrementWaitingTimes(int inc = 1); 122 123 virtual void BufferStat(int* num_packets, int* max_num_packets) const; 124 125 // Static method that properly deletes the first packet, and its payload 126 // array, in |packet_list|. Returns false if |packet_list| already was empty, 127 // otherwise true. 128 static bool DeleteFirstPacket(PacketList* packet_list); 129 130 // Static method that properly deletes all packets, and their payload arrays, 131 // in |packet_list|. 132 static void DeleteAllPackets(PacketList* packet_list); 133 134 // Static method returning true if |timestamp| is older than |timestamp_limit| 135 // but less than |horizon_samples| behind |timestamp_limit|. For instance, 136 // with timestamp_limit = 100 and horizon_samples = 10, a timestamp in the 137 // range (90, 100) is considered obsolete, and will yield true. 138 // Setting |horizon_samples| to 0 is the same as setting it to 2^31, i.e., 139 // half the 32-bit timestamp range. IsObsoleteTimestamp(uint32_t timestamp,uint32_t timestamp_limit,uint32_t horizon_samples)140 static bool IsObsoleteTimestamp(uint32_t timestamp, 141 uint32_t timestamp_limit, 142 uint32_t horizon_samples) { 143 return IsNewerTimestamp(timestamp_limit, timestamp) && 144 (horizon_samples == 0 || 145 IsNewerTimestamp(timestamp, timestamp_limit - horizon_samples)); 146 } 147 148 private: 149 size_t max_number_of_packets_; 150 PacketList buffer_; 151 RTC_DISALLOW_COPY_AND_ASSIGN(PacketBuffer); 152 }; 153 154 } // namespace webrtc 155 #endif // WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_BUFFER_H_ 156