1 /*
2  *  Copyright (c) 2019 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 MODULES_RTP_RTCP_SOURCE_RTP_PACKETIZER_AV1_H_
12 #define MODULES_RTP_RTCP_SOURCE_RTP_PACKETIZER_AV1_H_
13 
14 #include <stddef.h>
15 #include <stdint.h>
16 
17 #include <vector>
18 
19 #include "api/array_view.h"
20 #include "api/video/video_frame_type.h"
21 #include "modules/rtp_rtcp/source/rtp_format.h"
22 
23 namespace webrtc {
24 
25 class RtpPacketizerAv1 : public RtpPacketizer {
26  public:
27   RtpPacketizerAv1(rtc::ArrayView<const uint8_t> payload,
28                    PayloadSizeLimits limits,
29                    VideoFrameType frame_type);
30   ~RtpPacketizerAv1() override = default;
31 
NumPackets()32   size_t NumPackets() const override { return packets_.size() - packet_index_; }
33   bool NextPacket(RtpPacketToSend* packet) override;
34 
35  private:
36   struct Obu {
37     uint8_t header;
38     uint8_t extension_header;  // undefined if (header & kXbit) == 0
39     rtc::ArrayView<const uint8_t> payload;
40     int size;  // size of the header and payload combined.
41   };
42   struct Packet {
PacketPacket43     explicit Packet(int first_obu_index) : first_obu(first_obu_index) {}
44     // Indexes into obus_ vector of the first and last obus that should put into
45     // the packet.
46     int first_obu;
47     int num_obu_elements = 0;
48     int first_obu_offset = 0;
49     int last_obu_size;
50     // Total size consumed by the packet.
51     int packet_size = 0;
52   };
53 
54   // Parses the payload into serie of OBUs.
55   static std::vector<Obu> ParseObus(rtc::ArrayView<const uint8_t> payload);
56   // Returns the number of additional bytes needed to store the previous OBU
57   // element if an additonal OBU element is added to the packet.
58   static int AdditionalBytesForPreviousObuElement(const Packet& packet);
59   static std::vector<Packet> Packetize(rtc::ArrayView<const Obu> obus,
60                                        PayloadSizeLimits limits);
61   uint8_t AggregationHeader() const;
62 
63   const VideoFrameType frame_type_;
64   const std::vector<Obu> obus_;
65   const std::vector<Packet> packets_;
66   size_t packet_index_ = 0;
67 };
68 
69 }  // namespace webrtc
70 #endif  // MODULES_RTP_RTCP_SOURCE_RTP_PACKETIZER_AV1_H_
71