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_RTP_RTCP_SOURCE_RTP_RECEIVER_STRATEGY_H_ 12 #define WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_RECEIVER_STRATEGY_H_ 13 14 #include "webrtc/base/scoped_ptr.h" 15 #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp.h" 16 #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h" 17 #include "webrtc/modules/rtp_rtcp/source/rtp_utility.h" 18 #include "webrtc/system_wrappers/include/critical_section_wrapper.h" 19 #include "webrtc/typedefs.h" 20 21 namespace webrtc { 22 23 class TelephoneEventHandler; 24 25 // This strategy deals with media-specific RTP packet processing. 26 // This class is not thread-safe and must be protected by its caller. 27 class RTPReceiverStrategy { 28 public: 29 static RTPReceiverStrategy* CreateVideoStrategy(RtpData* data_callback); 30 static RTPReceiverStrategy* CreateAudioStrategy( 31 RtpData* data_callback, 32 RtpAudioFeedback* incoming_messages_callback); 33 ~RTPReceiverStrategy()34 virtual ~RTPReceiverStrategy() {} 35 36 // Parses the RTP packet and calls the data callback with the payload data. 37 // Implementations are encouraged to use the provided packet buffer and RTP 38 // header as arguments to the callback; implementations are also allowed to 39 // make changes in the data as necessary. The specific_payload argument 40 // provides audio or video-specific data. The is_first_packet argument is true 41 // if this packet is either the first packet ever or the first in its frame. 42 virtual int32_t ParseRtpPacket(WebRtcRTPHeader* rtp_header, 43 const PayloadUnion& specific_payload, 44 bool is_red, 45 const uint8_t* payload, 46 size_t payload_length, 47 int64_t timestamp_ms, 48 bool is_first_packet) = 0; 49 50 virtual TelephoneEventHandler* GetTelephoneEventHandler() = 0; 51 52 // Retrieves the last known applicable frequency. 53 virtual int GetPayloadTypeFrequency() const = 0; 54 55 // Computes the current dead-or-alive state. 56 virtual RTPAliveType ProcessDeadOrAlive( 57 uint16_t last_payload_length) const = 0; 58 59 // Returns true if we should report CSRC changes for this payload type. 60 // TODO(phoglund): should move out of here along with other payload stuff. 61 virtual bool ShouldReportCsrcChanges(uint8_t payload_type) const = 0; 62 63 // Notifies the strategy that we have created a new non-RED payload type in 64 // the payload registry. 65 virtual int32_t OnNewPayloadTypeCreated( 66 const char payloadName[RTP_PAYLOAD_NAME_SIZE], 67 int8_t payloadType, 68 uint32_t frequency) = 0; 69 70 // Invokes the OnInitializeDecoder callback in a media-specific way. 71 virtual int32_t InvokeOnInitializeDecoder( 72 RtpFeedback* callback, 73 int8_t payload_type, 74 const char payload_name[RTP_PAYLOAD_NAME_SIZE], 75 const PayloadUnion& specific_payload) const = 0; 76 77 // Checks if the payload type has changed, and returns whether we should 78 // reset statistics and/or discard this packet. 79 virtual void CheckPayloadChanged(int8_t payload_type, 80 PayloadUnion* specific_payload, 81 bool* should_discard_changes); 82 83 virtual int Energy(uint8_t array_of_energy[kRtpCsrcSize]) const; 84 85 // Stores / retrieves the last media specific payload for later reference. 86 void GetLastMediaSpecificPayload(PayloadUnion* payload) const; 87 void SetLastMediaSpecificPayload(const PayloadUnion& payload); 88 89 protected: 90 // The data callback is where we should send received payload data. 91 // See ParseRtpPacket. This class does not claim ownership of the callback. 92 // Implementations must NOT hold any critical sections while calling the 93 // callback. 94 // 95 // Note: Implementations may call the callback for other reasons than calls 96 // to ParseRtpPacket, for instance if the implementation somehow recovers a 97 // packet. 98 explicit RTPReceiverStrategy(RtpData* data_callback); 99 100 rtc::scoped_ptr<CriticalSectionWrapper> crit_sect_; 101 PayloadUnion last_payload_; 102 RtpData* data_callback_; 103 }; 104 } // namespace webrtc 105 106 #endif // WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_RECEIVER_STRATEGY_H_ 107