mirror of
https://gitee.com/xia-chu/ZLMediaKit.git
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113 lines
3.0 KiB
C++
113 lines
3.0 KiB
C++
/*
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* Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved.
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*
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* This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit).
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*
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* Use of this source code is governed by MIT-like license that can be found in the
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* LICENSE file in the root of the source tree. All contributing project authors
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* may be found in the AUTHORS file in the root of the source tree.
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*/
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#ifndef ZLMEDIAKIT_MP2VRTP_H
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#define ZLMEDIAKIT_MP2VRTP_H
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#include "MP2V.h"
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#include "Common/Stamp.h"
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#include "Rtsp/RtpCodec.h"
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namespace mediakit {
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// RFC 2250 MPEG Video-specific header (4 bytes)
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//
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// 0 1 2 3
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | MBZ |T| TR |N|S|B|E| P | | BFC | | FFC |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// AN FBV FFV
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static constexpr size_t kMP2VHeaderSize = 4;
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/**
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* MP2V (MPEG-2 Video) RTP 解码器
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* 将 MPEG-2 Video over RTP 解复用出 MP2V Frame
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* RFC 2250
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*/
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class MP2VRtpDecoder : public RtpCodec {
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public:
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using Ptr = std::shared_ptr<MP2VRtpDecoder>;
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MP2VRtpDecoder();
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/**
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* 输入 MPEG-2 Video RTP 包
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* @param rtp rtp包
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* @param key_pos 此参数忽略之
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*/
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bool inputRtp(const RtpPacket::Ptr &rtp, bool key_pos = true) override;
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private:
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bool decodeRtp(const RtpPacket::Ptr &rtp);
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void outputFrame(const RtpPacket::Ptr &rtp);
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void obtainFrame();
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private:
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bool _gop_dropped = true;
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bool _drop_flag = false;
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uint16_t _last_seq = 0;
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uint8_t _picture_type = 0;
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MP2VFrame::Ptr _frame;
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DtsGenerator _dts_generator;
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};
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/**
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* MP2V (MPEG-2 Video) RTP 编码器
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* 将 MPEG-2 Video 帧打包为 RTP
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* RFC 2250
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*/
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class MP2VRtpEncoder : public RtpCodec {
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public:
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using Ptr = std::shared_ptr<MP2VRtpEncoder>;
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/**
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* 输入 MPEG-2 Video 帧
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* @param frame 帧数据
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*/
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bool inputFrame(const Frame::Ptr &frame) override;
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private:
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/**
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* 构建 RFC 2250 MPEG Video-specific header
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* @param buf 输出缓冲区，至少4字节
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* @param data MPEG-2 ES 数据
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* @param size 数据大小
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* @param is_begin_of_slice 是否为 slice 起始
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* @param is_end_of_slice 是否为 slice 结束
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*/
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void buildMpvHeader(uint8_t *buf, const uint8_t *data, size_t size,
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bool is_begin_of_slice, bool is_end_of_slice);
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/**
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* 解析当前帧信息（picture type, temporal reference 等）
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*/
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void parsePictureInfo(const uint8_t *data, size_t size);
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/**
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* 查找 sequence header 是否存在
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*/
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bool hasSequenceHeader(const uint8_t *data, size_t size);
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private:
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uint16_t _temporal_ref = 0;
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uint8_t _picture_type = 0;
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uint8_t _fbv = 0;
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uint8_t _bfc = 0;
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uint8_t _ffv = 0;
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uint8_t _ffc = 0;
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bool _has_seq_header = false;
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};
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} // namespace mediakit
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#endif // ZLMEDIAKIT_MP2VRTP_H
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